Sample records for lead pipe scale

  1. Lead Pipe Scale Analysis Using Broad-Beam Argon Ion Milling to Elucidate Drinking Water Corrosion

    EPA Science Inventory

    Herein, we compared the characterization of lead pipe scale removed from a drinking water distribution system using two different cross section methods (conventional polishing and argon ion beam etching). The pipe scale solids were analyzed using scanning electron microscopy (SEM...

  2. Identification And Distribution Of Vanadinite (Pb5(V5+O4)3Cl) In Lead Pipe Corrosion By-Products

    EPA Science Inventory

    This study presents the first detailed look at vanadium (V) speciation in drinking water pipe corrosion scales. A pool of 34 scale layers from 15 lead or lead-lined pipes representing eight different municipal drinking water distribution systems in the Northeastern and Midwester...

  3. Importance of Pipe Deposits to Lead and Copper Rule Compliance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schock, Michael R.; Cantor, Abigail F.; Triantafyllidou, Simoni

    When Madison, Wis., exceeded the lead action level in 1992, residential and off-line tests suggested that lead release into the water was more complex than a lead solubility mechanism. Scale analyses (color and texture as well as mineralogical and elemental composition) of five excavated lead service lines (LSLs) revealed that accumulation of manganese (and iron) onto pipe walls had implications for lead corrosion by providing a high-capacity sink for lead. Manganese that accumulated from source well water onto pipe scales (up to 10% by weight of scale composition) served to capture and eventually transport lead to consumer taps. In addition,more » manganese sometimes obstructed the predominance of an insoluble (and thus potentially protective) plattnerite [Pb(IV) solid] scale layer. Full LSL replacement in Madison achieved Lead and Copper Rule compliance and a major reduction in lead contamination and exposure, supplemented by unidirectional flushing of water mains and manganese control in the source well water.« less

  4. Characteristics of lead corrosion scales formed during drinking water distribution and their potential influence on the release of lead and other contaminants.

    PubMed

    Kim, Eun Jung; Herrera, Jose E

    2010-08-15

    Destabilization of the corrosion scale present in lead pipes used in drinking water distribution systems is currently considered a major problem for municipalities serviced in part by lead pipes. Although several lead corrosion strategies have been deployed with success, a clear understanding of the chemistry of corrosion products present in the scale is needed for an effective lead control. This contribution focuses on a comprehensive characterization of the layers present in the corrosion scale formed on the inner surfaces of lead pipes used in the drinking water distribution system of the City on London, ON, Canada. Solid corrosion products were characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Toxic elements accumulated in the corrosion scale were also identified using inductively coupled plasma (ICP) spectrometry after acid digestion. Based on the XRD results, hydrocerussite was identified as the major lead crystalline corrosion phase in most of the pipes sampled, while cerussite was observed as the main crystalline component only in a few cases. Lead oxides including PbO(2) and Pb(3)O(4) were also observed in the inner layers of the corrosion scale. The presence of these highly oxidized lead species is rationalized in terms of the lead(II) carbonate phase transforming into lead(IV) oxide through an intermediate Pb(3)O(4) (2Pb(II)O x Pb(IV)O(2)) phase. In addition to lead corrosion products, an amorphous aluminosilicate phase was also identified in the corrosion scale. Its concentration is particularly high at the outer surface layers. Accumulation of toxic contaminants such as As, V, Sb, Cu, and Cr was observed in the corrosion scales, together with a strong correlation between arsenic accumulation and aluminum concentration.

  5. Heat pipes for wing leading edges of hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Boman, B. L.; Citrin, K. M.; Garner, E. C.; Stone, J. E.

    1990-01-01

    Wing leading edge heat pipes were conceptually designed for three types of vehicle: an entry research vehicle, aero-space plane, and advanced shuttle. A full scale, internally instrumented sodium/Hastelloy X heat pipe was successfully designed and fabricated for the advanced shuttle application. The 69.4 inch long heat pipe reduces peak leading edge temperatures from 3500 F to 1800 F. It is internally instrumented with thermocouples and pressure transducers to measure sodium vapor qualities. Large thermal gradients and consequently large thermal stresses, which have the potential of limiting heat pipe life, were predicted to occur during startup. A test stand and test plan were developed for subsequent testing of this heat pipe. Heat pipe manufacturing technology was advanced during this program, including the development of an innovative technique for wick installation.

  6. Mineralogy of Galvanic Corrosion By-products in Domestic Drinking Water Pipes

    EPA Science Inventory

    This study presents the results of a visual and mineralogical characterization of scales developed over long time periods at galvanically coupled lead-brass and lead-copper pipe joints from several different drinking water distribution systems. The long-term exposure aspect of t...

  7. Interrelationships between Blended Phosphate Treatment and Scale Formation for a Utility with Lead Pipes

    EPA Science Inventory

    Lead (Pb) in tap water (released from Pb-based plumbing materials) poses a serious public health concern. Water utilities experiencing Pb problems often use orthophosphate treatment, with the theory of forming insoluble Pb(II)-orthophosphate compounds on the pipe wall to inhibit ...

  8. Crystal and Morphological Phase Transformation of Pb(II) to Pb(IV) in Chlorinated Water

    EPA Science Inventory

    Herein, we show that an important transformation of Pb(II) to Pb(IV) under laboratory conditions which is intended to represent in real water flowing system in lead pipes. These results will give an insight in understanding the scale formation in lead pipes and dissolution of lea...

  9. Characteristics of iron corrosion scales and water quality variations in drinking water distribution systems of different pipe materials.

    PubMed

    Li, Manjie; Liu, Zhaowei; Chen, Yongcan; Hai, Yang

    2016-12-01

    Interaction between old, corroded iron pipe surfaces and bulk water is crucial to the water quality protection in drinking water distribution systems (WDS). Iron released from corrosion products will deteriorate water quality and lead to red water. This study attempted to understand the effects of pipe materials on corrosion scale characteristics and water quality variations in WDS. A more than 20-year-old hybrid pipe section assembled of unlined cast iron pipe (UCIP) and galvanized iron pipe (GIP) was selected to investigate physico-chemical characteristics of corrosion scales and their effects on water quality variations. Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Inductively Coupled Plasma (ICP) and X-ray Diffraction (XRD) were used to analyze micromorphology and chemical composition of corrosion scales. In bench testing, water quality parameters, such as pH, dissolved oxygen (DO), oxidation reduction potential (ORP), alkalinity, conductivity, turbidity, color, Fe 2+ , Fe 3+ and Zn 2+ , were determined. Scale analysis and bench-scale testing results demonstrated a significant effect of pipe materials on scale characteristics and thereby water quality variations in WDS. Characteristics of corrosion scales sampled from different pipe segments show obvious differences, both in physical and chemical aspects. Corrosion scales were found highly amorphous. Thanks to the protection of zinc coatings, GIP system was identified as the best water quality stability, in spite of high zinc release potential. It is deduced that the complicated composition of corrosion scales and structural break by the weld result in the diminished water quality stability in HP system. Measurement results showed that iron is released mainly in ferric particulate form. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Comparison of corrosion scales in full and partially replaced ...

    EPA Pesticide Factsheets

    Preliminary results from scales formed 38 weeks following the LSL replacement simulations revealed differences in scale formations amongst varying water qualities and pipe sequence. Rigs fed with dechlorinated tap water show distinct pH gradients between the galvanic and the background zones. Hydrocerussite and litharge are found both in field and pilot rigs. However, plumbonacrite, massicot, scrutinyite and plattnerite are only present in pipes harvested directly from the field. Laurionite, leadhillite, cerussite and calcite are found in rigs from the pilot. Cerussite is mostly present in the galvanic zones, close to the connection to the Cu pipe. Different types of scales are present in the rigs from the pilot and from the field, suggesting that differences in the formation in the scales and therefore differences in lead release from the pipes. The particulate Pb fraction in water samples is more important in samples from the pilot than from the field, median concentrations are 85X higher in partial LSL and 10X higher in full LSL in the pilot. Lead phosphates are present in the scales from the rigs treated with orthophosphate. Complete results will be obtained by the end of July 2016. The main objective is to compare scales from full and partial LSLs harvested from the field and from a pilot setup fed with water from the same distribution system and subjected to water quality changes.

  11. Comparison between Synthesized Lead Particles and Lead Solids Formed on Surfaces in Real Drinking Water Distribution Systems

    EPA Science Inventory

    The objective of this work is to compare the properties of lead solids formed during bench-scale precipitation experiments to solids found on lead pipe removed from real drinking water distribution systems and metal coupons used in pilot scale corrosion testing. Specifically, so...

  12. Role of iron and aluminum coagulant metal residuals and lead release from drinking water pipe materials.

    PubMed

    Knowles, Alisha D; Nguyen, Caroline K; Edwards, Marc A; Stoddart, Amina; McIlwain, Brad; Gagnon, Graham A

    2015-01-01

    Bench-scale experiments investigated the role of iron and aluminum residuals in lead release in a low alkalinity and high (> 0.5) chloride-to-sulfate mass ratio (CSMR) in water. Lead leaching was examined for two lead-bearing plumbing materials, including harvested lead pipe and new lead: tin solder, after exposure to water with simulated aluminum sulfate, polyaluminum chloride and ferric sulfate coagulation treatments with 1-25-μM levels of iron or aluminum residuals in the water. The release of lead from systems with harvested lead pipe was highly correlated with levels of residual aluminum or iron present in samples (R(2) = 0.66-0.88), consistent with sorption of lead onto the aluminum and iron hydroxides during stagnation. The results indicate that aluminum and iron coagulant residuals, at levels complying with recommended guidelines, can sometimes play a significant role in lead mobilization from premise plumbing.

  13. Long-Term Behavior of Simulated Partial Lead Service Line Replacements

    PubMed Central

    St. Clair, Justin; Cartier, Clement; Triantafyllidou, Simoni; Clark, Brandi; Edwards, Marc

    2016-01-01

    Abstract In this 48-month pilot study, long-term impacts of copper:lead galvanic connections on lead release to water were assessed without confounding differences in pipe exposure prehistory or disturbances arising from cutting lead pipe. Lead release was tracked from three lead service line configurations, including (1) 100% lead, (2) traditional partial replacement with 50% copper upstream of 50% lead, and (3) 50% lead upstream of 50% copper as a function of flow rate, connection types, and sampling methodologies. Elevated lead from galvanic corrosion worsened with time, with 140% more lead release from configurations representing traditional partial replacement configurations at 14 months compared to earlier data in the first 8 months. Even when sampled consistently at moderate flow rate (8 LPM) and collecting all water passing through service lines, conditions representing traditional partial service line configurations were significantly worse (≈40%) when compared to 100% lead pipe. If sampled at a high flow rate (32 LPM) and collecting 2 L samples from service lines, 100% of samples collected from traditional partial replacement configurations exceeded thresholds posing an acute health risk versus a 0% risk for samples from 100% lead pipe. Temporary removal of lead accumulations near Pb:Cu junctions and lead deposits from other downstream plastic pipes reduced risk of partial replacements relative to that observed for 100% lead. When typical brass compression couplings were used to connect prepassivated lead pipes, lead release spiked up to 10 times higher, confirming prior concerns raised at bench and field scale regarding adverse impacts of crevices and service line disturbances on lead release. To quantify semirandom particulate lead release from service lines in future research, whole-house filters have many advantages compared to other approaches. PMID:26989344

  14. A Tale of two Cities: Causes of Different Toxic Lead Releases From Lead and Brass Plumbing Components

    NASA Astrophysics Data System (ADS)

    Maynard, J. B.; Mast, D.; Hart, P.

    2006-05-01

    High lead (Pb) levels in drinking water have become a major health issue for many water distribution systems, especially Washington DC. This Pb comes from the dissolution of Pb minerals that coat lead service lines and Pb-containing brasses and solders. Using a variety of spectroscopic techniques (XRF, XRD, FTIR, laser micro-Raman), we studied pipe samples from Washington DC and from a similar utility system that has not had Pb releases. Both utilities use surface water and until recently both used chlorine as a disinfectant. DC switched to choramine disinfection, whereas the second utility did not. We found that both utilities have a similar array of Pb minerals present in their pipes, and that these minerals occur in distinct layers. From the pipe surface towards the water the sequence is litharge (PbO), cerussite (PbCO3), plattnerite (PbO2) and pyromorphite (Pb5[PO4]3F). We have also seen that the surface layer for DC is more discontinuous than in the pipes from utility 2 and the litharge from deeper layers is exposed. This mineral is especially soluble and may contribute to the extra Pb found in the DC water. We speculate that the switch to chloramine disinfection produced a lowering of the Eh at the scale surface with consequent dissolution of PbO2 followed by physical disruption of the pipe scales. Phosphate addition is now being practiced by both utilities for Pb control, and the PO4 content of the DC scales is increasing. XRD analysis shows a decrease in litharge and a corresponding increase in pyromorphite. For both utilities, we found that by far the most severe corrosion and scale buildup occurs at the junctions between brass and lead pipes. We attribute this to a galvanic corrosion of the brass by the adjacent lead sections. A consequence is that a portion of the Pb detected at customer's taps is coming not from the Pb service branches but from accelerated corrosion of Pb-containing brasses. Further reductions in Pb levels will require that releases from brass also be addressed. In addition to the Pb minerals found, which are all fairly well crystallized, there is in both utilities a surface layer of x-ray amorphous manganese oxide, which has a Raman spectrum similar to ramsdellite. For Utility 2, there is also an x-ray amorphous magnesium silicate. We speculate that this may be a form of sepiolite.

  15. Scale Formation under Blended Phosphate Treatment for a Utility with Lead Pipes

    EPA Science Inventory

    Conventional wisdom hypothesizes that the orthophosphate component of blended phosphate corrosion inhibitors causes the formation of low solubility lead-orthophosphate solids which inhibit lead release into drinking water. This study characterized the composition and morphology o...

  16. Importance of Pipe Deposits to Lead and Copper Rule Compliance

    EPA Science Inventory

    When Madison, WI exceeded the lead Action Level in 1992, residential and off-line tests suggested that lead release into the water was more complex than a simple lead solubility mechanism. In-depth scale analyses (color/texture, mineralogical and elemental composition) of 5 excav...

  17. CASE STUDIES IN THE INTEGRATED USE OF SCALE ANALYSES TO SOLVE LEAD PROBLEMS

    EPA Science Inventory

    All methods of controlling lead corrosion involve immobilizing lead into relatively insoluble compounds that deposit on the interior wall of water pipes. Many different solid phases can form under the disparate conditions that exist in distribution systems, which range in how the...

  18. Impact of treatment on scale formation and lead release from aged LSLs

    EPA Science Inventory

    Background Municipalities have been replacing the public part of lead service lines (LSLs) by copper piping, which often leaves a lead section on the private side, resulting in partial LSL replacements. Depending on water chemistry, such practices may result in galvanic and depo...

  19. Destabilization of Lead Pipe Scales in a Long-Term Vacant Home in Cincinnati

    EPA Science Inventory

    this presentation covers an ongoing study at a Cincinnati house, following the progression of lead release from a lead service line with different amounts of stagnation time and water use. This presentation is essentially the same as the talk cleared for AWWA ACE 2017, with some...

  20. Comparison of corrosion scales in full and partially replaced lead service lines after changes in water quality

    EPA Science Inventory

    Preliminary results from scales formed 38 weeks following the LSL replacement simulations revealed differences in scale formations amongst varying water qualities and pipe sequence. Rigs fed with dechlorinated tap water show distinct pH gradients between the galvanic and the back...

  1. THE USEFULNESS OF SCALE ANALYSIS: EXAMPLES FROM EASTERN MASSACHUSETTS

    EPA Science Inventory

    Many water system managers and operators are curious about the value of analyzing the scales of drinking water pipes. Approximately 20 sections of lead service lines were removed in 2002 from various locations throughout the greater Boston distribution system, and were sent to ...

  2. Surface analysis and depth profiling of corrosion products formed in lead pipes used to supply low alkalinity drinking water.

    PubMed

    Davidson, C M; Peters, N J; Britton, A; Brady, L; Gardiner, P H E; Lewis, B D

    2004-01-01

    Modern analytical techniques have been applied to investigate the nature of lead pipe corrosion products formed in pH adjusted, orthophosphate-treated, low alkalinity water, under supply conditions. Depth profiling and surface analysis have been carried out on pipe samples obtained from the water distribution system in Glasgow, Scotland, UK. X-ray diffraction spectrometry identified basic lead carbonate, lead oxide and lead phosphate as the principal components. Scanning electron microscopy/energy-dispersive x-ray spectrometry revealed the crystalline structure within the corrosion product and also showed spatial correlations existed between calcium, iron, lead, oxygen and phosphorus. Elemental profiling, conducted by means of secondary ion mass spectrometry (SIMS) and secondary neutrals mass spectrometry (SNMS) indicated that the corrosion product was not uniform with depth. However, no clear stratification was apparent. Indeed, counts obtained for carbonate, phosphate and oxide were well correlated within the depth range probed by SIMS. SNMS showed relationships existed between carbon, calcium, iron, and phosphorus within the bulk of the scale, as well as at the surface. SIMS imaging confirmed the relationship between calcium and lead and suggested there might also be an association between chloride and phosphorus.

  3. Practical Implications from Observed Lead Pipe Scale Mineralogy in a Blended Phosphate Treated System - slides

    EPA Science Inventory

    Many water utilities in the United States rely on the addition of phosphate-based corrosion inhibitors to optimize their corrosion control and comply with requirements of the Lead and Copper Rule. Orthophosphate is used on the theory of forming low solubility Pb(II)-orthophosphat...

  4. Factors influencing lead and iron release from some Egyptian drinking water pipes.

    PubMed

    Lasheen, M R; Sharaby, C M; El-Kholy, N G; Elsherif, I Y; El-Wakeel, S T

    2008-12-30

    The major objective of this study is to assess the effect of stagnation time, pipe age, pipes material and water quality parameters such as pH, alkalinity and chloride to sulfate mass ratio on lead and iron release from different types of water pipes used in Egypt namely polyvinyl chloride (PVC), polypropylene (PP) and galvanized iron (GI), by using fill and dump method. Low pH increased lead and iron release from pipes. Lead and iron release decreased as pH and alkalinity increased. Lead and iron release increased with increasing chloride to sulfate mass ratio in all pipes. EDTA was used as an example of natural organic matter which may be influence metals release. It is found that lead and iron release increased then this release decreased with time. In general, GI pipes showed to be the most effected by water quality parameters tested and the highest iron release. PVC pipes are the most lead releasing pipes while PP pipes are the least releasing.

  5. Heat-Pipe-Cooled Leading Edges for Hypersonic Vehicles

    NASA Technical Reports Server (NTRS)

    Glass, David E.

    2006-01-01

    Heat pipes can be used to effectively cool wing leading edges of hypersonic vehicles. . Heat-pipe leading edge development. Design validation heat pipe testing confirmed design. Three heat pipes embedded and tested in C/C. Single J-tube heat pipe fabricated and testing initiated. HPCLE work is currently underway at several locations.

  6. Structural impact and crashworthiness. Volume 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morton, J.

    1984-01-01

    These papers here were given at a conference on materials testing. The topics covered are mathematical modelling of materials, impact tests on pipes, and drop tests on scale models of lead shielded containers for radioactive materials.

  7. THE MINERALOGY OF PB SCALES IN DRINKING WATER DISTRIBUTION SYSTEMS AS REVEALED BY COMBINED XRD AND MICRO-RAMAN SPECTROSCOPY

    EPA Science Inventory

    Dissolving Pb from lead service lines and Pb-containing brasses and solders has become a major health issue for many water distribution systems. Knowledge of the mineralogy of scales in these pipes is key to modeling this dissolution. The traditional method of determining their ...

  8. Study on fluid-structure interaction in liquid oxygen feeding pipe systems using finite volume method

    NASA Astrophysics Data System (ADS)

    Wei, Xin; Sun, Bing

    2011-10-01

    The fluid-structure interaction may occur in space launch vehicles, which would lead to bad performance of vehicles, damage equipments on vehicles, or even affect astronauts' health. In this paper, analysis on dynamic behavior of liquid oxygen (LOX) feeding pipe system in a large scale launch vehicle is performed, with the effect of fluid-structure interaction (FSI) taken into consideration. The pipe system is simplified as a planar FSI model with Poisson coupling and junction coupling. Numerical tests on pipes between the tank and the pump are solved by the finite volume method. Results show that restrictions weaken the interaction between axial and lateral vibrations. The reasonable results regarding frequencies and modes indicate that the FSI affects substantially the dynamic analysis, and thus highlight the usefulness of the proposed model. This study would provide a reference to the pipe test, as well as facilitate further studies on oscillation suppression.

  9. Transient Simulation of Accumulating Particle Deposition in Pipe Flow

    NASA Astrophysics Data System (ADS)

    Hewett, James; Sellier, Mathieu

    2015-11-01

    Colloidal particles that deposit in pipe systems can lead to fouling which is an expensive problem in both the geothermal and oil & gas industries. We investigate the gradual accumulation of deposited colloids in pipe flow using numerical simulations. An Euler-Lagrangian approach is employed for modelling the fluid and particle phases. Particle transport to the pipe wall is modelled with Brownian motion and turbulent diffusion. A two-way coupling exists between the fouled material and the pipe flow; the local mass flux of depositing particles is affected by the surrounding fluid in the near-wall region. This coupling is modelled by changing the cells from fluid to solid as the deposited particles exceed each local cell volume. A similar method has been used to model fouling in engine exhaust systems (Paz et al., Heat Transfer Eng., 34(8-9):674-682, 2013). We compare our deposition velocities and deposition profiles with an experiment on silica scaling in turbulent pipe flow (Kokhanenko et al., 19th AFMC, 2014).

  10. Phase transition to turbulence in a pipe

    NASA Astrophysics Data System (ADS)

    Goldenfeld, Nigel

    Leo Kadanoff taught us much about phase transitions, turbulence and collective behavior. Here I explore the transition to turbulence in a pipe, showing how a collective mode determines the universality class. Near the transition, turbulent puffs decay either directly or through splitting, with characteristic time-scales that exhibit a super-exponential dependence on Reynolds number. Direct numerical simulations reveal that a collective mode, a so-called zonal flow emerges at large scales, activated by anisotropic turbulent fluctuations, as represented by Reynolds stress. This zonal flow imposes a shear on the turbulent fluctuations that tends to suppress their anisotropy, leading to a Landau theory of predator-prey type, in the directed percolation universality class. Stochastic simulations of this model reproduce the functional form and phenomenology of pipe flow experiments. Talk based on work performed with Hong-Yan Shih and Tsung-Lin Hsieh. This work was partially supported by the National Science Foundation through Grant NSF-DMR-1044901.

  11. Lead Water Pipes and Infant Mortality at the Turn of the Twentieth Century

    ERIC Educational Resources Information Center

    Troesken, Werner

    2008-01-01

    In 1897, about half of all American municipalities used lead pipes to distribute water. Employing data from Massachusetts, this paper compares infant death rates in cities that used lead water pipes to rates in cities that used nonlead pipes. In the average town in 1900, the use of lead pipes increased infant mortality by 25 to 50 percent.…

  12. 40. Photocopy of scale drawing (from Station 'L' office files, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. Photocopy of scale drawing (from Station 'L' office files, Portland, Oregon) Portland General Electric in house drawing, 12/6/1927 ELEVATION (TOP), SECTION (BOTTOM LEFT) AND PLAN (BOTTOM RIGHT) OF THE STEAM PIPING LEADING TO BOILER #13 BUILDING L4 - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  13. Asymptotic scalings of developing curved pipe flow

    NASA Astrophysics Data System (ADS)

    Ault, Jesse; Chen, Kevin; Stone, Howard

    2015-11-01

    Asymptotic velocity and pressure scalings are identified for the developing curved pipe flow problem in the limit of small pipe curvature and high Reynolds numbers. The continuity and Navier-Stokes equations in toroidal coordinates are linearized about Dean's analytical curved pipe flow solution (Dean 1927). Applying appropriate scaling arguments to the perturbation pressure and velocity components and taking the limits of small curvature and large Reynolds number yields a set of governing equations and boundary conditions for the perturbations, independent of any Reynolds number and pipe curvature dependence. Direct numerical simulations are used to confirm these scaling arguments. Fully developed straight pipe flow is simulated entering a curved pipe section for a range of Reynolds numbers and pipe-to-curvature radius ratios. The maximum values of the axial and secondary velocity perturbation components along with the maximum value of the pressure perturbation are plotted along the curved pipe section. The results collapse when the scaling arguments are applied. The numerically solved decay of the velocity perturbation is also used to determine the entrance/development lengths for the curved pipe flows, which are shown to scale linearly with the Reynolds number.

  14. Fabrication and Testing of a Leading-Edge-Shaped Heat Pipe

    NASA Technical Reports Server (NTRS)

    Glass, David E.; Merrigan, Michael A.; Sena, J. Tom; Reid, Robert S.

    1998-01-01

    The development of a refractory-composite/heat-pipe-cooled leading edge has evolved from the design stage to the fabrication and testing of a full size, leading-edge-shaped heat pipe. The heat pipe had a 'D-shaped' cross section and was fabricated from arc cast Mo-4lRe. An artery was included in the wick. Several issues were resolved with the fabrication of the sharp leading edge radius heat pipe. The heat pipe was tested in a vacuum chamber at Los Alamos National Laboratory using induction heating and was started up from the frozen state several times. However, design temperatures and heat fluxes were not obtained due to premature failure of the heat pipe resulting from electrical discharge between the induction heating apparatus and the heat pipe. Though a testing anomaly caused premature failure of the heat pipe, successful startup and operation of the heat pipe was demonstrated.

  15. Closed Form Equations for the Preliminary Design of a Heat-Pipe-Cooled Leading Edge

    NASA Technical Reports Server (NTRS)

    Glass, David E.

    1998-01-01

    A set of closed form equations for the preliminary evaluation and design of a heat-pipe-cooled leading edge is presented. The set of equations can provide a leading-edge designer with a quick evaluation of the feasibility of using heat-pipe cooling. The heat pipes can be embedded in a metallic or composite structure. The maximum heat flux, total integrated heat load, and thermal properties of the structure and heat-pipe container are required input. The heat-pipe operating temperature, maximum surface temperature, heat-pipe length, and heat pipe-spacing can be estimated. Results using the design equations compared well with those from a 3-D finite element analysis for both a large and small radius leading edge.

  16. Measuring the benefit of orthophosphate treatment on lead in drinking water.

    PubMed

    Cardew, P T

    2009-03-01

    Many water companies are adding low concentrations of orthophosphate to the water supply in order to reduce lead concentrations in drinking water produced from corrosion of lead service pipes. Despite the erratic nature of lead concentrations measured at customer properties it has been possible to quantify the impact of treatment on lead concentrations and thereby quantify the effectiveness of treatment at both a regional and zonal level. This showed that the treatment policy has delivered more than 90 per cent reduction in lead concentrations, and was largely in accordance with theory. Across the region, lead performance and the reduction in lead performance show significant variation. A large part of this variation can be accounted for by variations in the proportion of leaded properties supplied through lead service pipes. Analysis showed that the proportion of particulate lead has also reduced significantly over the last decade. This is attributed to improved mechanical robustness of the corrosion layer caused by changes in its physical structure. This appears to be a very slow process with a natural time-scale of years.

  17. Understanding the spatial formation and accumulation of fats, oils and grease deposits in the sewer collection system.

    PubMed

    Dominic, Christopher Cyril Sandeep; Szakasits, Megan; Dean, Lisa O; Ducoste, Joel J

    2013-01-01

    Sanitary sewer overflows are caused by the accumulation of insoluble calcium salts of fatty acids, which are formed by the reaction between fats, oils and grease (FOG) and calcium found in wastewaters. Different sewer structural configurations (i.e., manholes, pipes, wet wells), which vary spatially, along with other obstructions (roots intrusion) and pipe deformations (pipe sags), may influence the detrimental buildup of FOG deposits. The purpose of this study was to quantify the spatial variation in FOG deposit formation and accumulation in a pilot-scale sewer collection system. The pilot system contained straight pipes, manholes, roots intrusion, and a pipe sag. Calcium and oil were injected into the system and operated at alkaline (pH = 10) and neutral (pH = 7) pH conditions. Results showed that solid accumulations were slightly higher at neutral pH. Fourier transform infrared (FTIR) analysis on the solids samples confirmed that the solids were indeed calcium-based fatty acid salts. However, the fatty acid profiles of the solids deviated from the profile found from FOG deposits in sewer systems, which were primarily saturated fatty acids. These results confirm the work done previously by researchers and suggest an alternative fate of unsaturated fatty acids that does not lead to their incorporation in FOG deposits in full-scale sewer systems.

  18. THE CORROSION CONTROL-WATER QUALITY SPIDER WEB

    EPA Science Inventory

    This presentation provides an overview of new research results and emerging research needs with respect to both corrosion control issues, (lead, copper, iron) and to issues of inorganic contaminants that can form or accumulate in distribution system, water, pipe scales and distri...

  19. The lead industry and lead water pipes "A Modest Campaign".

    PubMed

    Rabin, Richard

    2008-09-01

    Lead pipes for carrying drinking water were well recognized as a cause of lead poisoning by the late 1800s in the United States. By the 1920s, many cities and towns were prohibiting or restricting their use. To combat this trend, the lead industry carried out a prolonged and effective campaign to promote the use of lead pipes. Led by the Lead Industries Association (LIA), representatives were sent to speak with plumbers' organizations, local water authorities, architects, and federal officials. The LIA also published numerous articles and books that extolled the advantages of lead over other materials and gave practical advice on the installation and repair of lead pipes. The LIA's activities over several decades therefore contributed to the present-day public health and economic cost of lead water pipes.

  20. Evolution of turbulence characteristics from straight to curved pipes

    NASA Astrophysics Data System (ADS)

    El Khoury, George K.; Noorani, Azad; Schlatter, Philipp; Fischer, Paul F.

    2012-11-01

    Large-scale direct numerical simulations are performed to study turbulent flow in straight and bent pipes at four different Reynolds numbers: Reb = 5300 , 11700 (bent and straight) and 19000 and 37700 (only straight). We consider a pipe of radius R and axial length 25 R with curvature parameter κ taken to be 0 , 0 . 01 and 0 . 1 for zero, mild and strong curvatures, respectively. The code used is Nek5000 based on the spectral element method. In the straight configuration, the obtained DNS data is carefully checked against other recent simulations, highlighting minute differences between the available data. Owing to a centrifugal instability mechanism, the flow in bent pipe (κ ≠ 0) develops counter-rotating vortices, so-called Dean vortices. The presence of the secondary motion thus induces substantial asymmetries both in the mean flow and turbulence characteristics for the bent pipe. These asymmetries tend to damp turbulence along the inner side and correspondingly enhance it along the upper side. The results are validated with recent experiments, and we could confirm the peculiar behaviour of the friction factor for specific curvatures and Re , leading to a lower friction in curved pipes than in straight pipes for the same mass flux.

  1. UNSOLVED PROBLEMS WITH CORROSION AND DISTRIBUTION SYSTEM INORGANICS

    EPA Science Inventory

    This presentation provides an overview of new research results and remaining research needs with respect to both corrosion control issues (lead, copper, iron) and to issues of inorganic contaminants that can form or accumulate in distribution system water, pipe scales and distrib...

  2. A catchment-scale groundwater model including sewer pipe leakage in an urban system

    NASA Astrophysics Data System (ADS)

    Peche, Aaron; Fuchs, Lothar; Spönemann, Peter; Graf, Thomas; Neuweiler, Insa

    2016-04-01

    Keywords: pipe leakage, urban hydrogeology, catchment scale, OpenGeoSys, HYSTEM-EXTRAN Wastewater leakage from subsurface sewer pipe defects leads to contamination of the surrounding soil and groundwater (Ellis, 2002; Wolf et al., 2004). Leakage rates at pipe defects have to be known in order to quantify contaminant input. Due to inaccessibility of subsurface pipe defects, direct (in-situ) measurements of leakage rates are tedious and associated with a high degree of uncertainty (Wolf, 2006). Proposed catchment-scale models simplify leakage rates by neglecting unsaturated zone flow or by reducing spatial dimensions (Karpf & Krebs, 2013, Boukhemacha et al., 2015). In the present study, we present a physically based 3-dimensional numerical model incorporating flow in the pipe network, in the saturated zone and in the unsaturated zone to quantify leakage rates on the catchment scale. The model consists of the pipe network flow model HYSTEM-EXTAN (itwh, 2002), which is coupled to the subsurface flow model OpenGeoSys (Kolditz et al., 2012). We also present the newly developed coupling scheme between the two flow models. Leakage functions specific to a pipe defect are derived from simulations of pipe leakage using spatially refined grids around pipe defects. In order to minimize computational effort, these leakage functions are built into the presented numerical model using unrefined grids around pipe defects. The resulting coupled model is capable of efficiently simulating spatially distributed pipe leakage coupled with subsurficial water flow in a 3-dimensional environment. References: Boukhemacha, M. A., Gogu, C. R., Serpescu, I., Gaitanaru, D., & Bica, I. (2015). A hydrogeological conceptual approach to study urban groundwater flow in Bucharest city, Romania. Hydrogeology Journal, 23(3), 437-450. doi:10.1007/s10040-014-1220-3. Ellis, J. B., & Revitt, D. M. (2002). Sewer losses and interactions with groundwater quality. Water Science and Technology, 45(3), 195-202. itwh (2002). Modellbeschreibung, Institut für technisch-wissenschaftliche Hydrologie GmbH, Hannover. Karpf, C. & Krebs, P. (2013). Modelling of groundwater infiltration into sewer systems. Urban Water Journal, 10:4, 221-229, DOI: 10.1080/1573062X.2012.724077. Kolditz, O., Bauer, S. et al. (2012). OpenGeoSys: an open source initiative for numerical simulation of thermo-hydro-mechanical/chemical (THM/C) processes in porous media. Env. Earth Sci. 67(2):589-599. Wolf, L., Held, I., Eiswirth, M., & Hötzl, H. (2004). Impact of leaky sewers on groundwater quality. Acta Hydrochimica et Hydrobiologica, 32(4-5), 361-373. doi:10.1002/aheh.200400538. Wolf, L. (2006). Influence of leaky sewer systems on groundwater resources beneath the city of Rastatt, Germany. Dissertation, University of Karlsruhe.

  3. Scalings at geothermal facilities exploring the Malm Aquifer (Bavarian Molasse Baisin)

    NASA Astrophysics Data System (ADS)

    Köhl, Bernhard; Herbrich, Moritz; Baumann, Thomas

    2016-04-01

    Scalings at geothermal facilities exploring the Malm Aquifer (Bavarian Molasse Basin) (Herbrich, M., Köhl, B., Baumann, T.) Scalings are a widespread problem among geothermal plants which exploit the Malm Aquifer in the Bavarian Molasse Zone. They effect the technical and economic efficiency of geothermal plants and cause costly revisions of the geothermal cycle. Scalings observed at geothermal facilities exploring the Malm Aquifer mainly consist of different CaCO3 polymorphs and are found at the motor, in the pumps and pipes and throughout the groundlevel facilities including the heat exchangers. There are two main processes leading to a disruption of the carbonate equilibrium and causing these CaCO3 scalings: local temperature peaks and degassing of less soluble gases due to local pressure drops. While the increase of the temperature leads to a local supersaturation at the hot surface of e.g. the motor, the formation of gas bubbles strips all soluble gases from the solution according to the Henry equilibrum constants, thus shifting the carbonate-equilibrium towards less soluble CaCO3. In order to prevent the formation of scalings, these processes have to be quantified. Therefore, we investigated the scalings in all sections of the geothermal cycle at geothermal plants in the Malm Aquifer. So far, we have sampled scalings from the pumps and the production pipes after three exchanges of the pump, scalings collected in the particle filters, scalings from the ground level geothermal facilities, and scalings from the injection pipes. The samples were characterized by REM-EDX, XRD, and image processing to assess the mineralogical features and the elemental composition. The porosity and bulk density were measured to assess the mass of the deposits and to calculate the kinetics of the formation. All together, this generated a unique quantitative dataset with a spatial resolution of 9 m along the production tubes. The thickness of the scalings first decreases from the outlet of the pump to about 600-400 m b.s.l. From here, the thickness of the scaling increases again towards the well head. While the scalings at the well head show a crystalline structure with little porosity, the scalings at the pump reveal a rather sponge-like structure. The thickness of the scalings above the pump shows a dependency on the pump type. The overall thickness correlated to the produced volume of thermal water is on the order of 500-1500 μm/10 ^ 6 m ^ 3. As the geothermal water is produced, the gas bubbles, which are formed at the pump, slowly dissolve under more steady flow conditions and less new scalings build, since the precipitation of some material reduced the saturation. Closer to the well head, scalings are formed as the pressure in the production pipe decreases. The processes leading to scalings are controlled by the hydrochemical conditions and the gas loading, both largely differing at the different exploration sites. Therefore, we will focus on the acquisition of additional data from other sites to quantify and predict the formation of the scalings and to develop countermeasures.

  4. The Lead Industry and Lead Water Pipes “A MODEST CAMPAIGN”

    PubMed Central

    Rabin, Richard

    2008-01-01

    Lead pipes for carrying drinking water were well recognized as a cause of lead poisoning by the late 1800s in the United States. By the 1920s, many cities and towns were prohibiting or restricting their use. To combat this trend, the lead industry carried out a prolonged and effective campaign to promote the use of lead pipes. Led by the Lead Industries Association (LIA), representatives were sent to speak with plumbers’ organizations, local water authorities, architects, and federal officials. The LIA also published numerous articles and books that extolled the advantages of lead over other materials and gave practical advice on the installation and repair of lead pipes. The LIA’s activities over several decades therefore contributed to the present-day public health and economic cost of lead water pipes. PMID:18633098

  5. Contaminant Accumulation in Many New England Lead Pipe Scales

    EPA Science Inventory

    Previous work has shown that contaminants such as Al, As and Ra can accumulate in drinking water distribution system solids. The release of accumulated contaminants back into the water supply could conceivably result in elevated levels at consumers' taps. The objective of this s...

  6. 40 CFR 141.43 - Prohibition on use of lead pipes, solder, and flux.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Prohibition on use of lead pipes..., Including Monitoring Regulations and Prohibition on Lead Use § 141.43 Prohibition on use of lead pipes... water system shall be lead free as defined by paragraph (d) of this section. This paragraph (a)(1) shall...

  7. 40 CFR 141.43 - Prohibition on use of lead pipes, solder, and flux.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Prohibition on use of lead pipes..., Including Monitoring Regulations and Prohibition on Lead Use § 141.43 Prohibition on use of lead pipes... water system shall be lead free as defined by paragraph (d) of this section. This paragraph (a)(1) shall...

  8. Leaching of lead from new unplasticized polyvinyl chloride (uPVC) pipes into drinking water.

    PubMed

    Zhang, Yuanyuan; Lin, Yi-Pin

    2015-06-01

    Unplasticized polyvinyl chloride (uPVC) pipes have been used in the premise plumbing system due to their high strength, long-term durability, and low cost. uPVC pipes, however, may contain lead due to the use of lead compounds as the stabilizer during the manufacturing process. The release of lead from three locally purchased uPVC pipes was investigated in this study. The effects of various water quality parameters including pH value, temperature, and type of disinfectant on the rate of lead release were examined. The elemental mapping obtained using scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) confirmed the presence of lead on the inner surfaces of the uPVC pipes and their surface lead weight percentages were determined. The leachable lead concentration for each pipe was determined using high strength acidic EDTA solutions (pH 4, EDTA = 100 mg/L). Lead leaching experiments using tap water and reconstituted tape water under static conditions showed that the rate of lead release increased with the decreasing pH value and increasing temperature. In the presence of monochloramine, lead release was faster than that in the presence of free chlorine.

  9. Mineralogical Evidence of Galvanic Corrosion in Domestic, Drinking Water Pipes

    EPA Science Inventory

    Drinking water distribution system (DWDS) piping contains numerous examples of galvanically-coupled metals (e.g., soldered copper pipe joints, copper-lead pipes joined during partial replacements of lead service lines). The possible role of galvanic corrosion in the release of l...

  10. High performance felt-metal-wick heat pipe for solar receivers

    NASA Astrophysics Data System (ADS)

    Andraka, Charles E.; Moss, Timothy A.; Baturkin, Volodymyr; Zaripov, Vladlen; Nishchyk, Oleksandr

    2016-05-01

    Sodium heat pipes have been identified as a potentially effective heat transport approach for CSP systems that require near-isothermal input to power cycles or storage, such as dish Stirling and highly recuperated reheat-cycle supercritical CO2 turbines. Heat pipes offer high heat flux capabilities, leading to small receivers, as well as low exergetic losses through isothermal coupling with the engine. Sandia developed a felt metal wick approach in the 1990's, and demonstrated very high performance1. However, multiple durability issues arose, primarily the structural collapse of the wick at temperature over short time periods. NTUU developed several methods of improving robustness of the wick2, but the resulting wick had limited performance capabilities. For application to CSP systems, the wick structures must retain high heat pipe performance with robustness for long term operation. In this paper we present our findings in developing an optimal balance between performance and ruggedness, including operation of a laboratory-scale heat pipe for over 5500 hours so far. Application of heat pipes to dish-Stirling systems has been shown to increase performance as much as 20%3, and application to supercritical CO2 systems has been proposed.

  11. Fabrication and Testing of Mo-Re Heat Pipes Embedded in Carbon/Carbon

    NASA Technical Reports Server (NTRS)

    Glass, David E.; Merrigan, Michael A.; Sena, J. Tom

    1998-01-01

    Refractory-composite/heat-pipe-cooled wing an tail leading edges are being considered for use on hypersonic vehicles to limit maximum temperatures to values below material reuse limits and to eliminate the need to actively cool the leading edges. The development of a refractory-composite/heat-pipe-cooled leading edge has evolved from the design stage to the fabrication and testing of heat pipes embedded in carbon/carbon (C/C). A three-foot-long, molybdenum-rhenium heat pipe with a lithium working fluid was fabricated and tested at an operating temperature of 2460 F to verify the individual heat-pipe design. Following the fabrication of this heat pipe, three additional heat pipes were fabricated and embedded in C/C. The C/C heat-pipe test article was successfully tested using quartz lamps in a vacuum chamber in both a horizontal and vertical orientation. Start up and steady state data are presented for the C/C heat-pipe test article. Radiography and eddy current evaluations were performed on the test article.

  12. Geotechnical Centrifuge Experiments to Evaluate Piping in Foundation Soils

    DTIC Science & Technology

    2014-05-01

    verifiable results. These tests were successful in design , construction, and execution of a realistic simulation of internal erosion leading to failure...possible “scale effects,” “modeling of models” testing protocol should be included in the test program. Also, the model design should minimize the scale...recommendations for improving the centrifuge tests include the following: • Design improved system for reservoir control to provide definitive and

  13. THE OCCURRENCE OF CONTAMINANT ACCUMULATION IN LEAD PIPE SCALES FROM DOMESTIC DRINKING WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    Previous work has shown that contaminants, such as Al, As and Ra, can accumulate in drinking water distribution system solids. The release of accumulated contaminants back into the water supply could result in elevated levels at consumers’ taps, and current monitoring practices d...

  14. The Occurrence of Contaminant Accumulation in Lead Pipe Scales from Domestic Drinking Water Distribution Systems-ABSTRACT

    EPA Science Inventory

    Previous work has shown that contaminants such as Al, As and Ra, can accumulate in drinking water distribution system solids. The release of accumulated contaminants back into the water supply could conceivably result in elevated levels at consumers’ taps. The current regulatory...

  15. Occurrence of contaminant accumulation in lead pipe scales from domestic drinking-water distribution systems.

    PubMed

    Schock, Michael R; Hyland, Robert N; Welch, Meghan M

    2008-06-15

    Previously, contaminants, such as AI, As, and Ra, have been shown to accumulate in drinking-water distribution system solids. Accumulated contaminants could be periodically released back into the water supply causing elevated levels at consumers taps, going undetected by most current regulatory monitoring practices and consequently constituting a hidden risk. The objective of this study was to determine the occurrence of over 40 major scale constituents, regulated metals, and other potential metallic inorganic contaminants in drinking-water distribution system Pb (lead) or Pb-lined service lines. The primary method of analysis was inductively coupled plasma-atomic emission spectroscopy, following complete decomposition of scale material. Contaminants and scale constituents were categorized by their average concentrations, and many metals of potential health concern were found to occur at levels sufficient to result in elevated levels at the consumer's taps if they were to be mobilized. The data indicate distinctly nonconservative behavior for many inorganic contaminants in drinking-water distribution systems. This finding suggests an imminent need for further research into the transport and fate of contaminants throughout drinking-water distribution system pipes, as well as a re-evaluation of monitoring protocols in order to more accurately determine the scope and levels of potential consumer exposure.

  16. Impact of treatment on Pb release from full and partially replaced harvested Lead Service Lines (LSLs).

    PubMed

    Cartier, Clément; Doré, Evelyne; Laroche, Laurent; Nour, Shokoufeh; Edwards, Marc; Prévost, Michèle

    2013-02-01

    Release of lead from 80% partially replaced service lines was compared to full lead service lines using harvested-stabilized lead pipes and field brass connectors. After more than a year of stabilization, lead release was consistent with field samples. Over the relatively short duration partial replacement of lead pipe by copper pipe (3 months), generated high lead release, attributed to galvanic corrosion, resulting in a final outcome for lead release that was even worse than for a full lead pipe. Increased lead release was especially evident at higher flow rates. Orthophosphate reduced lead release from full lead pipes by 64%. For partially replaced samples with copper, lead concentrations were unchanged by phosphate dosing at moderate flow (103 ± 265 vs 169 ± 349 μg/L) and were increased to very high levels when sampled at high flow rates (1001 ± 1808 vs 257 ± 224 μg/L). The increase lead release was in the form of particulate lead (>90%). In comparison to the condition without treatment, increased sulfate treatment had little impact on lead release from 100%-Pb rigs but reduced lead release from partially replaced lead pipes with copper. Our results also raise questions concerning protocols based on short 30 min stagnation (as those used in Canada) due to their incapacity to consider particulate lead release generated mostly after longer stagnation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Thermostructural applications of heat pipes for cooling leading edges of high-speed aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Camarda, Charles J.; Glass, David E.

    1992-01-01

    Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests, eight aerothermal tests, and twenty-seven supplemental radiant heating tests. Cold-wall heating rates ranged from 21 to 57 Btu/sq ft-s and maximum operating temperatures ranged from 1090 to 1520 F. Follow-on studies investigated the application of heat pipes to cool the stagnation regions of single-stage-to-orbit and advanced shuttle vehicles. Results of those studies indicate that a 'D-shaped' structural design can reduce the mass of the heat-pipe concept by over 44 percent compared to a circular heat-pipe geometry. Simple analytical models for heat-pipe startup from the frozen state (working fluid initially frozen) were adequate to approximate transient, startup, and steady-state heat-pipe performance. Improvement in analysis methods has resulted in the development of a finite-element analysis technique to predict heat-pipe startup from the frozen state. However, current requirements of light-weight design and reliability suggest that metallic heat pipes embedded in a refractory composite material should be used. This concept is the concept presently being evaluated for NASP. A refractory-composite/heat-pipe-cooled wing leading edge is currently being considered for the National Aero-Space Plane (NASP). This concept uses high-temperature refractory-metal/lithium heat pipes embedded within a refractory-composite structure and is significantly lighter than an actively cooled wing leading edge because it eliminates the need for active cooling during ascent and descent. Since the NASP vehicle uses cryogenic hydrogen to cool structural components and then burns this fuel in the combustor, hydrogen necessary for descent cooling only, when the vehicle is unpowered, is considered to be a weight penalty. Details of the design of the refractory-composite/heat-pipe-cooled wing leading edge are currently being investigated. Issues such as thermal contact resistance and thermal stress are also being investigated.

  18. Thermostructural applications of heat pipes for cooling leading edges of high-speed aerospace vehicles

    NASA Astrophysics Data System (ADS)

    Camarda, Charles J.; Glass, David E.

    1992-10-01

    Heat pipes have been considered for use on wing leading edge for over 20 years. Early concepts envisioned metal heat pipes cooling a metallic leading edge. Several superalloy/sodium heat pipes were fabricated and successfully tested for wing leading edge cooling. Results of radiant heat and aerothermal testing indicate the feasibility of using heat pipes to cool the stagnation region of shuttle-type space transportation systems. The test model withstood a total seven radiant heating tests, eight aerothermal tests, and twenty-seven supplemental radiant heating tests. Cold-wall heating rates ranged from 21 to 57 Btu/sq ft-s and maximum operating temperatures ranged from 1090 to 1520 F. Follow-on studies investigated the application of heat pipes to cool the stagnation regions of single-stage-to-orbit and advanced shuttle vehicles. Results of those studies indicate that a 'D-shaped' structural design can reduce the mass of the heat-pipe concept by over 44 percent compared to a circular heat-pipe geometry. Simple analytical models for heat-pipe startup from the frozen state (working fluid initially frozen) were adequate to approximate transient, startup, and steady-state heat-pipe performance. Improvement in analysis methods has resulted in the development of a finite-element analysis technique to predict heat-pipe startup from the frozen state. However, current requirements of light-weight design and reliability suggest that metallic heat pipes embedded in a refractory composite material should be used. This concept is the concept presently being evaluated for NASP. A refractory-composite/heat-pipe-cooled wing leading edge is currently being considered for the National Aero-Space Plane (NASP). This concept uses high-temperature refractory-metal/lithium heat pipes embedded within a refractory-composite structure and is significantly lighter than an actively cooled wing leading edge because it eliminates the need for active cooling during ascent and descent. Since the NASP vehicle uses cryogenic hydrogen to cool structural components and then burns this fuel in the combustor, hydrogen necessary for descent cooling only, when the vehicle is unpowered, is considered to be a weight penalty. Details of the design of the refractory-composite/heat-pipe-cooled wing leading edge are currently being investigated. Issues such as thermal contact resistance and thermal stress are also being investigated.

  19. Interactions of metallic substances and acidic ground water in the New Jersey Coastal Plan

    USGS Publications Warehouse

    Barringer, J.L.

    1994-01-01

    Four ancillary studies were undertaken in support of an investigation into the extent and distribution of corrosive ground water in the Kirkwood- Cohansey aquifer system of southern New Jersey.The ancillary studies were (1) analysis of tap-water samples for metals and the acquisition of metal data from a county study, (2) leaching experiments in which copper pipe with various types of solder were exposed to a variety of ground-water types, (3) analysis of pipe-scale deposits on plumbing from houses with wells that tap the Kirkwood-Cohansey aquifer system, and (4) measurement of corrosion rates for carbon steel and copper exposed to shallow ground water from the Kirkwood-Cohansey aquifer system. The results studies indicate that substantial concentrations of lead, copper, and zinc can leach from plumbing materials exposed to corrosive water from the Kirkwood-Cohansey aquifer system, and that leaching appears more pronounced during the summer than during the winter. The leaching experiments indicate that the corrosiveness of water, as estimated by the calculation of a corrosion index (the Aggressive Index), is related to the concentration of trace metals in the leachate.Further, although the leaching of lead-bearing solders produced lead concentrations in leachate above the Primary Drinking Water Criterion in effect at the time of the study (50 micrograms per liter), no potentially toxic levels of metals were leached from lead-free solders, although copper concentrations in some leachate samples were in excess of the Secondary Drinking Water Criterion of 1,000 micrograms per liter. Analyses of pipe-scale deposits indicate the formation of iron oxide coatings on some copper-pipe interiors exposed to untreated well water. Treated water from a public-supply system precipitated copper carbonate and copper chloride minerals. Corrosion rates measured for copper exposed to corrosive water from the Kirkwood-Cohansey aquifer system were slow (less than 0.0254 millimeters per year). Carbon-steel corrosion rates were faster; the fastest rate (0.229 millimeters per year) was measured in oxygen-saturated water.

  20. Fabrication of lithium/C-103 alloy heat pipes for sharp leading edge cooling

    NASA Astrophysics Data System (ADS)

    Ai, Bangcheng; Chen, Siyuan; Yu, Jijun; Lu, Qin; Han, Hantao; Hu, Longfei

    2018-05-01

    In this study, lithium/C-103 alloys heat pipes are proposed for sharp leading edge cooling. Three models of lithium/C-103 alloy heat pipes were fabricated. And their startup properties were tested by radiant heat tests and aerothermal tests. It is found that the startup temperature of lithium heat pipe was about 860 °C. At 1000 °C radiant heat tests, the operating temperature of lithium/C-103 alloy heat pipe is lower than 860 °C. Thus, startup failure occurs. At 1100 °C radiant heat tests and aerothermal tests, the operating temperature of lithium/C-103 alloy heat pipe is higher than 860 °C, and the heat pipe starts up successfully. The startup of lithium/C-103 alloy heat pipe decreases the leading edge temperature effectively, which endows itself good ablation resistance. After radiant heat tests and aerothermal tests, all the heat pipe models are severely oxidized because of the C-103 poor oxidation resistance. Therefore, protective coatings are required for further applications of lithium/C-103 alloy heat pipes.

  1. Heat pipe cooling for scramjet engines

    NASA Technical Reports Server (NTRS)

    Silverstein, Calvin C.

    1986-01-01

    Liquid metal heat pipe cooling systems have been investigated for the combustor liner and engine inlet leading edges of scramjet engines for a missile application. The combustor liner is cooled by a lithium-TZM molybdenum annular heat pipe, which incorporates a separate lithium reservoir. Heat is initially absorbed by the sensible thermal capacity of the heat pipe and liner, and subsequently by the vaporization and discharge of lithium to the atmosphere. The combustor liner temperature is maintained at 3400 F or less during steady-state cruise. The engine inlet leading edge is fabricated as a sodium-superalloy heat pipe. Cooling is accomplished by radiation of heat from the aft surface of the leading edge to the atmosphere. The leading edge temperature is limited to 1700 F or less. It is concluded that heat pipe cooling is a viable method for limiting scramjet combustor liner and engine inlet temperatures to levels at which structural integrity is greatly enhanced.

  2. Effect of PVC and iron materials on Mn(II) deposition in drinking water distribution systems.

    PubMed

    Cerrato, José M; Reyes, Lourdes P; Alvarado, Carmen N; Dietrich, Andrea M

    2006-08-01

    Polyvinyl chloride (PVC) and iron pipe materials differentially impacted manganese deposition within a drinking water distribution system that experiences black water problems because it receives soluble manganese from a surface water reservoir that undergoes biogeochemical cycling of manganese. The water quality study was conducted in a section of the distribution system of Tegucigalpa, Honduras and evaluated the influence of iron and PVC pipe materials on the concentrations of soluble and particulate iron and manganese, and determined the composition of scales formed on PVC and iron pipes. As expected, total Fe concentrations were highest in water from iron pipes. Water samples obtained from PVC pipes showed higher total Mn concentrations and more black color than that obtained from iron pipes. Scanning electron microscopy demonstrated that manganese was incorporated into the iron tubercles and thus not readily dislodged from the pipes by water flow. The PVC pipes contained a thin surface scale consisting of white and brown layers of different chemical composition; the brown layer was in contact with the water and contained 6% manganese by weight. Mn composed a greater percentage by weight of the PVC scale than the iron pipe scale; the PVC scale was easily dislodged by flowing water. This research demonstrates that interactions between water and the infrastructure used for its supply affect the quality of the final drinking water.

  3. Piping dynamics in mid-altitude mountains under a temperate climate: the Bieszczady Mts., the Eastern Carpathians

    NASA Astrophysics Data System (ADS)

    Bernatek-Jakiel, Anita; Jakiel, Michał; Krzemień, Kazimierz

    2017-04-01

    Soil erosion is caused not only by overland flow, but also by subsurface flow. Piping which is a process of mechanical removal of soil particles by concentrated subsurface flow is frequently being overlooked and not accounted for in soil erosion studies. However, it seems that it is far more widespread than it has often been supposed. Furthermore, our knowledge about piping dynamics and its quantification currently relies on a limited number of data available for mainly loess-mantled areas and marl badlands. Therefore, this research aims to recognize piping dynamics in mid-altitude mountains under a temperate climate, where piping occurs in Cambisols, not previously considered as piping-prone soils. The survey was carried out in the Bereźnica Wyżna catchment (305 ha), in the Bieszczady Mts. (the Eastern Carpathians, Poland), where 188 collapsed pipes were mapped. The research was based on the monitoring of selected piping systems located within grasslands (1971-1974, 2013-2016). The development of piping systems is mainly induced by the elongation of pipes and creation of new collapses (closed depressions and sinkholes), rather than by the enlargement of existing piping forms, or the deepening of pipes. It draws attention to the role of dense vegetation (grasslands) in the delay of pipe collapses and, also, to the boundary of pipe development (soil-bedrock interface). The obtained results reveal an episodic, and even stochastic nature of piping activity, expressed by varied one-year and short-term (3 years) erosion rates, and pipe elongation. Changes in soil loss vary significantly between different years (up to 27.36 t ha-1 y-1), reaching the rate of 1.34 t ha-1 y-1 for the 45-year study period. The elongation of pipes also differs, from no changes to 36 m during one year. The results indicate that soil loss due to piping can cause high soil loss even in highly vegetated lands (grasslands), which are generally considered as areas without a significant erosion problem. The scale of piping in the study area is at least by three orders of magnitude higher than surface erosion rates (i.e. sheet and rill erosion) under a similar land use (grasslands), and it is comparable to the scale of surface soil erosion on arable lands. It means that piping is an important sediment source for fluvial systems, and it leads to significant soil loss in mid-altitude mountains under a temperate climate. This study is supported by the National Science Centre of Poland, as a part of the first author's project - PRELUDIUM 3 (DEC-2012/05/N/ST10/03926). The first author was also granted the ETIUDA 3 doctoral scholarship (UMO-2015/16/T/ST10/00505) financed by the National Science Centre of Poland.

  4. Theoretical analysis for scaling law of thermal blooming based on optical phase deference

    NASA Astrophysics Data System (ADS)

    Sun, Yunqiang; Huang, Zhilong; Ren, Zebin; Chen, Zhiqiang; Guo, Longde; Xi, Fengjie

    2016-10-01

    In order to explore the laser propagation influence of thermal blooming effect of pipe flow and to analysis the influencing factors, scaling law theoretical analysis of the thermal blooming effects in pipe flow are carry out in detail based on the optical path difference caused by thermal blooming effects in pipe flow. Firstly, by solving the energy coupling equation of laser beam propagation, the temperature of the flow is obtained, and then the optical path difference caused by the thermal blooming is deduced. Through the analysis of the influence of pipe size, flow field and laser parameters on the optical path difference, energy scaling parameters Ne=nTαLPR2/(ρɛCpπR02) and geometric scaling parameters Nc=νR2/(ɛL) of thermal blooming for the pipe flow are derived. Secondly, for the direct solution method, the energy coupled equations have analytic solutions only for the straight tube with Gauss beam. Considering the limitation of directly solving the coupled equations, the dimensionless analysis method is adopted, the analysis is also based on the change of optical path difference, same scaling parameters for the pipe flow thermal blooming are derived, which makes energy scaling parameters Ne and geometric scaling parameters Nc have good universality. The research results indicate that when the laser power and the laser beam diameter are changed, thermal blooming effects of the pipeline axial flow caused by optical path difference will not change, as long as you keep energy scaling parameters constant. When diameter or length of the pipe changes, just keep the geometric scaling parameters constant, the pipeline axial flow gas thermal blooming effects caused by optical path difference distribution will not change. That is to say, when the pipe size and laser parameters change, if keeping two scaling parameters with constant, the pipeline axial flow thermal blooming effects caused by the optical path difference will not change. Therefore, the energy scaling parameters and the geometric scaling parameters can really describe the gas thermal blooming effect in the axial pipe flow. These conclusions can give a good reference for the construction of the thermal blooming test system of laser system. Contrasted with the thermal blooming scaling parameters of the Bradley-Hermann distortion number ND and Fresnel number NF, which were derived based on the change of far field beam intensity distortion, the scaling parameters of pipe flow thermal blooming deduced from the optical path deference variation are very suitable for the optical system with short laser propagation distance, large Fresnel number and obviously changed optical path deference.

  5. Modeling of transient heat pipe operation

    NASA Technical Reports Server (NTRS)

    Colwell, Gene T.

    1987-01-01

    The use of heat pipes is being considered as a means of reducing the peak temperature and large thermal gradients at the leading edges of reentry vehicles and hypersonic aircraft and in nuclear reactors. In the basic cooling concept, the heat pipe covers the leading edge, a portion of the lower wing surface, and a portion of the upper wing surface. Aerodynamic heat is mainly absorbed at the leading edge and transported through the heat pipe to the upper and lower wing surface, where it is rejected by thermal radiation and convection. Basic governing equations are written to determine the startup, transient, and steady state performance of a haet pipe which has initially frozen alkali-metal as the working fluid.

  6. Health and aesthetic impacts of copper corrosion on drinking water.

    PubMed

    Dietrich, A M; Glindemann, D; Pizarro, F; Gidi, V; Olivares, M; Araya, M; Camper, A; Duncan, S; Dwyer, S; Whelton, A J; Younos, T; Subramanian, S; Burlingame, G A; Khiari, D; Edwards, M

    2004-01-01

    Traditional research has focused on the visible effects of corrosion--failures, leaks, and financial debits--and often overlooked the more hidden health and aesthetic aspects. Clearly, corrosion of copper pipe can lead to levels of copper in the drinking water that exceed health guidelines and cause bitter or metallic tasting water. Because water will continue to be conveyed to consumers worldwide through metal pipes, the water industry has to consider both the effects of water quality on corrosion and the effects of corrosion on water quality. Integrating four key factors--chemical/biological causes, economics, health and aesthetics--is critical for managing the distribution system to produce safe water that consumers will use with confidence. As technological developments improve copper pipes to minimize scaling and corrosion, it is essential to consider the health and aesthetic effects on an equal plane with chemical/biological causes and economics to produce water that is acceptable for public consumption.

  7. Morphological and physicochemical characteristics of iron corrosion scales formed under different water source histories in a drinking water distribution system.

    PubMed

    Yang, Fan; Shi, Baoyou; Gu, Junnong; Wang, Dongsheng; Yang, Min

    2012-10-15

    The corrosion scales on iron pipes could have great impact on the water quality in drinking water distribution systems (DWDS). Unstable and less protective corrosion scale is one of the main factors causing "discolored water" issues when quality of water entering into distribution system changed significantly. The morphological and physicochemical characteristics of corrosion scales formed under different source water histories in duration of about two decades were systematically investigated in this work. Thick corrosion scales or densely distributed corrosion tubercles were mostly found in pipes transporting surface water, but thin corrosion scales and hollow tubercles were mostly discovered in pipes transporting groundwater. Magnetite and goethite were main constituents of iron corrosion products, but the mass ratio of magnetite/goethite (M/G) was significantly different depending on the corrosion scale structure and water source conditions. Thick corrosion scales and hard shell of tubercles had much higher M/G ratio (>1.0), while the thin corrosion scales had no magnetite detected or with much lower M/G ratio. The M/G ratio could be used to identify the characteristics and evaluate the performances of corrosion scales formed under different water conditions. Compared with the pipes transporting ground water, the pipes transporting surface water were more seriously corroded and could be in a relatively more active corrosion status all the time, which was implicated by relatively higher siderite, green rust and total iron contents in their corrosion scales. Higher content of unstable ferric components such as γ-FeOOH, β-FeOOH and amorphous iron oxide existed in corrosion scales of pipes receiving groundwater which was less corroded. Corrosion scales on groundwater pipes with low magnetite content had higher surface area and thus possibly higher sorption capacity. The primary trace inorganic elements in corrosion products were Br and heavy metals. Corrosion products obtained from pipes transporting groundwater had higher levels of Br, Ti, Ba, Cu, Sr, V, Cr, La, Pb and As. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Thermostructural applications of heat pipes

    NASA Technical Reports Server (NTRS)

    Peeples, M. E.; Reeder, J. C.; Sontag, K. E.

    1979-01-01

    The feasibility of integrating heat pipes in high temperature structure to reduce local hot spot temperature was evaluated for a variety of hypersonic aerospace vehicles. From an initial list of twenty-two potential applications, the single stage to orbit wing leading edge showed the greatest promise and was selected for preliminary design of an integrated heat pipe thermostructural system. The design consisted of a Hastelloy X assembly with sodium heat pipe passages aligned normal to the wing leading edge. A d-shaped heat pipe cross section was determined to be optimum from the standpoint of structural weight.

  9. Treatment Strategies for Lead in Drinking Water

    EPA Science Inventory

    Lead pipes are capable of lasting hundreds of years. Conservatively, there are over 12 million, still serving drinking water in the US. Probably, this is a substantial underestimate. Leaded solder joining copper pipe abounds. Leaded brasses have dominated the materials used for...

  10. A coupled approach for the three-dimensional simulation of pipe leakage in variably saturated soil

    NASA Astrophysics Data System (ADS)

    Peche, Aaron; Graf, Thomas; Fuchs, Lothar; Neuweiler, Insa

    2017-12-01

    In urban water pipe networks, pipe leakage may lead to subsurface contamination or to reduced waste water treatment efficiency. The quantification of pipe leakage is challenging due to inaccessibility and unknown hydraulic properties of the soil. A novel physically-based model for three-dimensional numerical simulation of pipe leakage in variably saturated soil is presented. We describe the newly implemented coupling between the pipe flow simulator HYSTEM-EXTRAN and the groundwater flow simulator OpenGeoSys and its validation. We further describe a novel upscaling of leakage using transfer functions derived from numerical simulations. This upscaling enables the simulation of numerous pipe defects with the benefit of reduced computation times. Finally, we investigate the response of leakage to different time-dependent pipe flow events and conclude that larger pipe flow volume and duration lead to larger leakage while the peak position in time has a small effect on leakage.

  11. Iron release from corroded iron pipes in drinking water distribution systems: effect of dissolved oxygen.

    PubMed

    Sarin, P; Snoeyink, V L; Bebee, J; Jim, K K; Beckett, M A; Kriven, W M; Clement, J A

    2004-03-01

    Iron release from corroded iron pipes is the principal cause of "colored water" problems in drinking water distribution systems. The corrosion scales present in corroded iron pipes restrict the flow of water, and can also deteriorate the water quality. This research was focused on understanding the effect of dissolved oxygen (DO), a key water quality parameter, on iron release from the old corroded iron pipes. Corrosion scales from 70-year-old galvanized iron pipe were characterized as porous deposits of Fe(III) phases (goethite (alpha-FeOOH), magnetite (Fe(3)O(4)), and maghemite (alpha-Fe(2)O(3))) with a shell-like, dense layer near the top of the scales. High concentrations of readily soluble Fe(II) content was present inside the scales. Iron release from these corroded pipes was investigated for both flow and stagnant water conditions. Our studies confirmed that iron was released to bulk water primarily in the ferrous form. When DO was present in water, higher amounts of iron release was observed during stagnation in comparison to flowing water conditions. Additionally, it was found that increasing the DO concentration in water during stagnation reduced the amount of iron release. Our studies substantiate that increasing the concentration of oxidants in water and maintaining flowing conditions can reduce the amount of iron release from corroded iron pipes. Based on our studies, it is proposed that iron is released from corroded iron pipes by dissolution of corrosion scales, and that the microstructure and composition of corrosion scales are important parameters that can influence the amount of iron released from such systems.

  12. Effect of sulfate on the transformation of corrosion scale composition and bacterial community in cast iron water distribution pipes.

    PubMed

    Yang, Fan; Shi, Baoyou; Bai, Yaohui; Sun, Huifang; Lytle, Darren A; Wang, Dongsheng

    2014-08-01

    The chemical stability of iron corrosion scales and the microbial community of biofilm in drinking water distribution system (DWDS) can have great impact on the iron corrosion and corrosion product release, which may result in "red water" issues, particularly under the situation of source water switch. In this work, experimental pipe loops were set up to investigate the effect of sulfate on the dynamical transformation characteristics of iron corrosion products and bacterial community in old cast iron distribution pipes. All the test pipes were excavated from existing DWDS with different source water supply histories, and the test water sulfate concentration was in the range of 50-350 mg/L. Pyrosequencing of 16S rRNA was used for bacterial community analysis. The results showed that iron release increased markedly and even "red water" occurred for pipes with groundwater supply history when feed water sulfate elevated abruptly. However, the iron release of pipes with only surface water supply history changed slightly without noticeable color even the feed water sulfate increased multiply. The thick-layered corrosion scales (or densely distributed tubercles) on pipes with surface water supply history possessed much higher stability due to the larger proportion of stable constituents (mainly Fe3O4) in their top shell layer; instead, the rather thin and uniform non-layered corrosion scales on pipes with groundwater supply history contained relatively higher proportion of less stable iron oxides (e.g. β-FeOOH, FeCO3 and green rust). The less stable corrosion scales tended to be more stable with sulfate increase, which was evidenced by the gradually decreased iron release and the increased stable iron oxides. Bacterial community analysis indicated that when switching to high sulfate water, iron reducing bacteria (IRB) maintained dominant for pipes with stable corrosion scales, while significant increase of sulfur oxidizing bacteria (SOB), sulfate reducing bacteria (SRB) and iron oxidizing bacteria (IOB) was observed for pipes with less stable corrosion scales. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Osborne Reynolds pipe flow: Direct simulation from laminar through gradual transition to fully developed turbulence.

    PubMed

    Wu, Xiaohua; Moin, Parviz; Adrian, Ronald J; Baltzer, Jon R

    2015-06-30

    The precise dynamics of breakdown in pipe transition is a century-old unresolved problem in fluid mechanics. We demonstrate that the abruptness and mysteriousness attributed to the Osborne Reynolds pipe transition can be partially resolved with a spatially developing direct simulation that carries weakly but finitely perturbed laminar inflow through gradual rather than abrupt transition arriving at the fully developed turbulent state. Our results with this approach show during transition the energy norms of such inlet perturbations grow exponentially rather than algebraically with axial distance. When inlet disturbance is located in the core region, helical vortex filaments evolve into large-scale reverse hairpin vortices. The interaction of these reverse hairpins among themselves or with the near-wall flow when they descend to the surface from the core produces small-scale hairpin packets, which leads to breakdown. When inlet disturbance is near the wall, certain quasi-spanwise structure is stretched into a Lambda vortex, and develops into a large-scale hairpin vortex. Small-scale hairpin packets emerge near the tip region of the large-scale hairpin vortex, and subsequently grow into a turbulent spot, which is itself a local concentration of small-scale hairpin vortices. This vortex dynamics is broadly analogous to that in the boundary layer bypass transition and in the secondary instability and breakdown stage of natural transition, suggesting the possibility of a partial unification. Under parabolic base flow the friction factor overshoots Moody's correlation. Plug base flow requires stronger inlet disturbance for transition. Accuracy of the results is demonstrated by comparing with analytical solutions before breakdown, and with fully developed turbulence measurements after the completion of transition.

  14. Osborne Reynolds pipe flow: Direct simulation from laminar through gradual transition to fully developed turbulence

    PubMed Central

    Wu, Xiaohua; Moin, Parviz; Adrian, Ronald J.; Baltzer, Jon R.

    2015-01-01

    The precise dynamics of breakdown in pipe transition is a century-old unresolved problem in fluid mechanics. We demonstrate that the abruptness and mysteriousness attributed to the Osborne Reynolds pipe transition can be partially resolved with a spatially developing direct simulation that carries weakly but finitely perturbed laminar inflow through gradual rather than abrupt transition arriving at the fully developed turbulent state. Our results with this approach show during transition the energy norms of such inlet perturbations grow exponentially rather than algebraically with axial distance. When inlet disturbance is located in the core region, helical vortex filaments evolve into large-scale reverse hairpin vortices. The interaction of these reverse hairpins among themselves or with the near-wall flow when they descend to the surface from the core produces small-scale hairpin packets, which leads to breakdown. When inlet disturbance is near the wall, certain quasi-spanwise structure is stretched into a Lambda vortex, and develops into a large-scale hairpin vortex. Small-scale hairpin packets emerge near the tip region of the large-scale hairpin vortex, and subsequently grow into a turbulent spot, which is itself a local concentration of small-scale hairpin vortices. This vortex dynamics is broadly analogous to that in the boundary layer bypass transition and in the secondary instability and breakdown stage of natural transition, suggesting the possibility of a partial unification. Under parabolic base flow the friction factor overshoots Moody’s correlation. Plug base flow requires stronger inlet disturbance for transition. Accuracy of the results is demonstrated by comparing with analytical solutions before breakdown, and with fully developed turbulence measurements after the completion of transition. PMID:26080447

  15. Osborne Reynolds pipe flow: Direct simulation from laminar through gradual transition to fully developed turbulence

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Xiaohua; Moin, Parviz; Adrian, Ronald J.

    We report that the precise dynamics of breakdown in pipe transition is a century-old unresolved problem in fluid mechanics. We demonstrate that the abruptness and mysteriousness attributed to the Osborne Reynolds pipe transition can be partially resolved with a spatially developing direct simulation that carries weakly but finitely perturbed laminar inflow through gradual rather than abrupt transition arriving at the fully developed turbulent state. Our results with this approach show during transition the energy norms of such inlet perturbations grow exponentially rather than algebraically with axial distance. When inlet disturbance is located in the core region, helical vortex filaments evolvemore » into large-scale reverse hairpin vortices. The interaction of these reverse hairpins among themselves or with the near-wall flow when they descend to the surface from the core produces small-scale hairpin packets, which leads to breakdown. When inlet disturbance is near the wall, certain quasi-spanwise structure is stretched into a Lambda vortex, and develops into a large-scale hairpin vortex. Small-scale hairpin packets emerge near the tip region of the large-scale hairpin vortex, and subsequently grow into a turbulent spot, which is itself a local concentration of small-scale hairpin vortices. This vortex dynamics is broadly analogous to that in the boundary layer bypass transition and in the secondary instability and breakdown stage of natural transition, suggesting the possibility of a partial unification. Under parabolic base flow the friction factor overshoots Moody’s correlation. Plug base flow requires stronger inlet disturbance for transition. Finally, accuracy of the results is demonstrated by comparing with analytical solutions before breakdown, and with fully developed turbulence measurements after the completion of transition.« less

  16. Osborne Reynolds pipe flow: Direct simulation from laminar through gradual transition to fully developed turbulence

    DOE PAGES

    Wu, Xiaohua; Moin, Parviz; Adrian, Ronald J.; ...

    2015-06-15

    We report that the precise dynamics of breakdown in pipe transition is a century-old unresolved problem in fluid mechanics. We demonstrate that the abruptness and mysteriousness attributed to the Osborne Reynolds pipe transition can be partially resolved with a spatially developing direct simulation that carries weakly but finitely perturbed laminar inflow through gradual rather than abrupt transition arriving at the fully developed turbulent state. Our results with this approach show during transition the energy norms of such inlet perturbations grow exponentially rather than algebraically with axial distance. When inlet disturbance is located in the core region, helical vortex filaments evolvemore » into large-scale reverse hairpin vortices. The interaction of these reverse hairpins among themselves or with the near-wall flow when they descend to the surface from the core produces small-scale hairpin packets, which leads to breakdown. When inlet disturbance is near the wall, certain quasi-spanwise structure is stretched into a Lambda vortex, and develops into a large-scale hairpin vortex. Small-scale hairpin packets emerge near the tip region of the large-scale hairpin vortex, and subsequently grow into a turbulent spot, which is itself a local concentration of small-scale hairpin vortices. This vortex dynamics is broadly analogous to that in the boundary layer bypass transition and in the secondary instability and breakdown stage of natural transition, suggesting the possibility of a partial unification. Under parabolic base flow the friction factor overshoots Moody’s correlation. Plug base flow requires stronger inlet disturbance for transition. Finally, accuracy of the results is demonstrated by comparing with analytical solutions before breakdown, and with fully developed turbulence measurements after the completion of transition.« less

  17. Effect of pipe corrosion scales on chlorine dioxide consumption in drinking water distribution systems.

    PubMed

    Zhang, Zhe; Stout, Janet E; Yu, Victor L; Vidic, Radisav

    2008-01-01

    Previous studies showed that temperature and total organic carbon in drinking water would cause chlorine dioxide (ClO(2)) loss in a water distribution system and affect the efficiency of ClO(2) for Legionella control. However, among the various causes of ClO(2) loss in a drinking water distribution system, the loss of disinfectant due to the reaction with corrosion scales has not been studied in detail. In this study, the corrosion scales from a galvanized iron pipe and a copper pipe that have been in service for more than 10 years were characterized by energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The impact of these corrosion scale materials on ClO(2) decay was investigated in de-ionized water at 25 and 45 degrees C in a batch reactor with floating glass cover. ClO(2) decay was also investigated in a specially designed reactor made from the iron and copper pipes to obtain more realistic reaction rate data. Goethite (alpha-FeOOH) and magnetite (Fe(3)O(4)) were identified as the main components of iron corrosion scale. Cuprite (Cu(2)O) was identified as the major component of copper corrosion scale. The reaction rate of ClO(2) with both iron and copper oxides followed a first-order kinetics. First-order decay rate constants for ClO(2) reactions with iron corrosion scales obtained from the used service pipe and in the iron pipe reactor itself ranged from 0.025 to 0.083 min(-1). The decay rate constant for ClO(2) with Cu(2)O powder and in the copper pipe reactor was much smaller and it ranged from 0.0052 to 0.0062 min(-1). Based on these results, it can be concluded that the corrosion scale will cause much more significant ClO(2) loss in corroded iron pipes of the distribution system than the total organic carbon that may be present in finished water.

  18. Guided wave attenuation in coated pipes buried in sand

    NASA Astrophysics Data System (ADS)

    Leinov, Eli; Cawley, Peter; Lowe, Michael J. S.

    2016-02-01

    Long-range guided wave testing (GWT) is routinely used for the monitoring and detection of corrosion defects in above ground pipelines in various industries. The GWT test range in buried, coated pipelines is greatly reduced compared to aboveground pipelines due to energy leakage into the embedding soil. In this study, we aim to increase test ranges for buried pipelines. The effect of pipe coatings on the T(0,1) and L(0,2) guided wave attenuation is investigated using a full-scale experimental apparatus and model predictions. Tests are performed on a fusion-bonded epoxy (FBE)-coated 8" pipe, buried in loose and compacted sand over a frequency range of 10-35 kHz. The application of a low impedance coating is shown to effectively decouple the influence of the sand on the ultrasound leakage from the buried pipe. We demonstrate ultrasonic isolation of a buried pipe by coating the pipe with a Polyethylene (PE)-foam layer that has a smaller impedance than both pipe and sand and the ability to withstand the overburden load from the sand. The measured attenuation in the buried PE-foam-FBE-coated pipe is substantially reduced, in the range of 0.3-1.2 dBm-1 for loose and compacted sand conditions, compared to buried FBE-coated pipe without the PE-foam, where the measured attenuation is in the range of 1.7-4.7 dBm-1. The acoustic properties of the PE-foam are measured independently using ultrasonic interferometry technique and used in model predictions of guided wave propagation in a buried coated pipe. Good agreement is found between the attenuation measurements and model predictions. The attenuation exhibits periodic peaks in the frequency domain corresponding to the through-thickness resonance frequencies of the coating layer. The large reduction in guided wave attenuation for PE-coated pipes would lead to greatly increased GWT test ranges, so such coatings would be attractive for new pipeline installations.

  19. A feasibility study of heat-pipe-cooled leading edges for hypersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Silverstein, C. C.

    1971-01-01

    A theoretical study of the use of heat pipe structures for cooling the leading edges of hypersonic cruise aircraft was carried out over a Mach number range of 6 to 12. Preliminary design studies showed that a heat pipe cooling structure with a 33-in. chordwise length could maintain the maximum temperature of a 65 deg sweepback wing with a 0.5-in. leading edge radius below 1600 F during cruise at Mach 8. A few relatively minor changes in the steady-state design of the structure were found necessary to insure satisfactory cooling during the climb to cruise speed and altitude. It was concluded that heat pipe cooling is an attractive, feasible technique for limiting leading edge temperatures of hypersonic cruise aircraft.

  20. Hypersonic aerospace vehicle leading edge cooling using heat pipe, transpiration and film cooling techniques

    NASA Astrophysics Data System (ADS)

    Modlin, James Michael

    An investigation was conducted to study the feasibility of cooling hypersonic vehicle leading edge structures exposed to severe aerodynamic surface heat fluxes using a combination of liquid metal heat pipes and surface mass transfer cooling techniques. A generalized, transient, finite difference based hypersonic leading edge cooling model was developed that incorporated these effects and was demonstrated on an assumed aerospace plane-type wing leading edge section and a SCRAMJET engine inlet leading edge section. The hypersonic leading edge cooling model was developed using an existing, experimentally verified heat pipe model. Two applications of the hypersonic leading edge cooling model were examined. An assumed aerospace plane-type wing leading edge section exposed to a severe laminar, hypersonic aerodynamic surface heat flux was studied. A second application of the hypersonic leading edge cooling model was conducted on an assumed one-quarter inch nose diameter SCRAMJET engine inlet leading edge section exposed to both a transient laminar, hypersonic aerodynamic surface heat flux and a type 4 shock interference surface heat flux. The investigation led to the conclusion that cooling leading edge structures exposed to severe hypersonic flight environments using a combination of liquid metal heat pipe, surface transpiration, and film cooling methods appeared feasible.

  1. 77 FR 41967 - Certain Circular Welded Carbon Steel Pipes and Tubes From India, Thailand, and Turkey; Certain...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-17

    ... Pipes and Tubes From India, Thailand, and Turkey; Certain Circular Welded Non-Alloy Steel Pipe From... on (1) certain circular welded carbon steel pipes and tubes from India, Thailand, and Turkey; (2... circular welded carbon steel pipes and tubes from Turkey would likely lead to continuation or recurrence of...

  2. Direct numerical simulation of turbulence in a bent pipe

    NASA Astrophysics Data System (ADS)

    Schlatter, Philipp; Noorani, Azad

    2013-11-01

    A series of direct numerical simulations of turbulent flow in a bent pipe is presented. The setup employs periodic (cyclic) boundary conditions in the axial direction, leading to a nominally infinitely long pipe. The discretisation is based on the high-order spectral element method, using the code Nek5000. Four different curvatures, defined as the ratio between pipe radius and coil radius, are considered: κ = 0 (straight), 0.01 (mild curvature), 0.1 and 0.3 (strong curvature), at bulk Reynolds numbers of up to 11700 (corresponding to Reτ = 360 in the straight pipe case). The result show the turbulence-reducing effect of the curvature (similar to rotation), leading close to relaminarisation in the inner side; the outer side, however, remains fully turbulent. Prpoer orthogonal decomposition (POD) is used to extract the dominant modes, in an effort to explain low-frequency switching of sides inside the pipe. A number of additional interesting features are explored, which include sub-straight and sub-laminar drag for specific choices of curvature and Reynolds number: In particular the case with sub-laminar drag is investigated further, and our analysis shows the existence of a spanwise wave in the bent pipe, which in fact leads to lower overall pressure drop.

  3. Reusable high-temperature heat pipes and heat pipe panels

    NASA Technical Reports Server (NTRS)

    Camarda, Charles J. (Inventor); Ransone, Philip O. (Inventor)

    1989-01-01

    A reusable, durable heat pipe which is capable of operating at temperatures up to about 3000 F in an oxidizing environment and at temperatures above 3000 F in an inert or vacuum environment is produced by embedding a refractory metal pipe within a carbon-carbon composite structure. A reusable, durable heat pipe panel is made from an array of refractory-metal pipes spaced from each other. The reusable, durable, heat-pipe is employed to fabricate a hypersonic vehicle leading edge and nose cap.

  4. 76 FR 9608 - Certain Welded Large Diameter Line Pipe From Mexico

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-18

    ... Large Diameter Line Pipe From Mexico AGENCY: United States International Trade Commission. ACTION... duty order on certain welded large diameter line pipe from Mexico. For further information concerning... welded large diameter line pipe from Mexico would not be likely to lead to continuation or recurrence of...

  5. Improvement of Liquefiable Foundation Conditions Beneath Existing Structures.

    DTIC Science & Technology

    1985-08-01

    filter zones, and drains. Drilling fluids can cause hydraulic fracturing . These hazards can lead to to piping and hvdraulic fracturing Compression . 7...with results of piping and hydraulic fracturing (Continued) * Site conditions have been classified into three cases; Case 1 is for beneath -d...which could lead to piping and hydraulic fracturing Soil Reinforcement 16. Vibro-replacement See methods 2 and 3 stone and sand columns applicable to

  6. 26. DETAIL OF CONCRETE PIPE SUPPORTS LEADING TO NEW LIQUID ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. DETAIL OF CONCRETE PIPE SUPPORTS LEADING TO NEW LIQUID HYDROGEN TANK FARM; VIEW TO WEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28402, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  7. 14. PIPE MACHINE, WORK BENCH, SCALE, RADIAL DRILL AND STOVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. PIPE MACHINE, WORK BENCH, SCALE, RADIAL DRILL AND STOVE (L TO R) LOOKING WEST. - W. A. Young & Sons Foundry & Machine Shop, On Water Street along Monongahela River, Rices Landing, Greene County, PA

  8. In-Situ Air Sparaing: Engineering and Design

    DTIC Science & Technology

    2008-01-31

    Construction Materials. Although PVC casing is commonly used, flexible or rigid polyethylene pipe may be more efficient for certain excavation methods, such as...depth, etc.) Piping insulation/ heat tape installed Piping flushed/cleaned/pressure tested Subsurface as-built equipment...4-4 Figure 4-2 Pilot-Scale Piping and Instrumentation Diagram

  9. Ultrasonic isolation of buried pipes

    NASA Astrophysics Data System (ADS)

    Leinov, Eli; Lowe, Michael J. S.; Cawley, Peter

    2016-02-01

    Long-range guided wave testing (GWT) is used routinely for the monitoring and detection of corrosion defects in above ground pipelines. The GWT test range in buried, coated pipelines is greatly reduced compared to above ground configurations due to energy leakage into the embedding soil. In this paper, the effect of pipe coatings on the guided wave attenuation is investigated with the aim of increasing test ranges for buried pipelines. The attenuation of the T(0,1) and L(0,2) guided wave modes is measured using a full-scale experimental apparatus in a fusion-bonded epoxy (FBE)-coated 8 in. pipe, buried in loose and compacted sand. Tests are performed over a frequency range typically used in GWT of 10-35 kHz and compared with model predictions. It is shown that the application of a low impedance coating between the FBE layer and the sand effectively decouples the influence of the sand on the ultrasound leakage from the buried pipe. Ultrasonic isolation of a buried pipe is demonstrated by coating the pipe with a Polyethylene (PE)-foam layer that has a smaller impedance than both the pipe and sand, and has the ability to withstand the overburden load from the sand. The measured attenuation in the buried PE-foam-FBE-coated pipe is found to be substantially reduced, in the range of 0.3-1.2 dB m-1 for loose and compacted sand conditions, compared to measured attenuation of 1.7-4.7 dB m-1 in the buried FBE-coated pipe without the PE-foam. The acoustic properties of the PE-foam are measured independently using ultrasonic interferometry and incorporated into model predictions of guided wave propagation in buried coated pipe. Good agreement is found between the experimental measurements and model predictions. The attenuation exhibits periodic peaks in the frequency domain corresponding to the through-thickness resonance frequencies of the coating layer. The large reduction in guided wave attenuation for PE-coated pipes would lead to greatly increased GWT test ranges; such coatings would be attractive for new pipeline installations.

  10. Microbial Community Profile of a Lead Service Line Removed from a Drinking Water Distribution System

    EPA Science Inventory

    A corroded lead water pipe was removed from a drinking water distribution system and the microbial community was profiled using 16S rDNA techniques. This is the first report of the characterization of biofilm on a surface of a corroded lead drinking water pipe. The majority of ...

  11. Characterization of corrosion scale formed on stainless steel delivery pipe for reclaimed water treatment.

    PubMed

    Cui, Yong; Liu, Shuming; Smith, Kate; Yu, Kanghua; Hu, Hongying; Jiang, Wei; Li, Yuhong

    2016-01-01

    To reveal corrosion behavior of stainless steel delivery pipe used in reclaimed water treatment, this research focused on the morphological, mineralogical and chemical characteristics of stainless steel corrosion scale and corroded passive film. Corrosion scale and coupon samples were taken from a type 304 pipe delivering reclaimed water to a clear well in service for more than 12 years. Stainless steel corrosion scales and four representative pipe coupons were investigated using mineralogy and material science research methods. The results showed corrosion scale was predominantly composed of goethite, lepidocrocite, hematite, magnetite, ferrous oxide, siderite, chrome green and chromite, the same as that of corroded pipe coupons. Hence, corrosion scale can be identified as podiform chromite deposit. The loss of chromium in passive film is a critical phenomenon when stainless steel passive film is damaged by localized corrosion. This may provide key insights toward improving a better comprehension of the formation of stainless steel corrosion scale and the process of localized corrosion. The localized corrosion behavior of stainless steel is directly connected with reclaimed water quality parameters such as residual chlorine, DO, Cl(-) and SO4(2-). In particular, when a certain amount of residual chlorine in reclaimed water is present as an oxidant, ferric iron is the main chemical state of iron minerals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. 24 CFR 3280.605 - Joints and connections.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... assembled for tightness. Pipe threads shall be fully engaged with the threads of the fitting. Plastic pipe... standard. Pipe ends shall be reamed out to size of bore. All burrs, chips, cutting oil and foreign matter..., made with solder having not more than 0.2 percent lead. (4) Plastic pipe, fittings and joints. Plastic...

  13. 78 FR 60897 - Certain Welded Large Diameter Line Pipe From Japan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-02

    ... Diameter Line Pipe From Japan Determination On the basis of the record \\1\\ developed in the subject five... order on certain welded large diameter line pipe from Japan would likely to lead to continuation or... Line Pipe from Japan: Investigation No. 731-TA-919 (Second Review). By order of the Commission. Issued...

  14. 76 FR 76437 - Certain Welded Stainless Steel Pipe From Korea and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-07

    ... Welded Stainless Steel Pipe From Korea and Taiwan Determination On the basis of the record \\1\\ developed... antidumping duty orders on certain welded stainless steel pipe from Korea and Taiwan would be likely to lead... 2011), entitled Certain Welded Stainless Steel Pipe from Korea and Taiwan, Investigation Nos. 731-TA...

  15. Physical Model Study of Flowerpot Discharge Outlet, Western Closure Complex, New Orleans, Louisiana

    DTIC Science & Technology

    2013-05-01

    FPDO ........................................................................................ 12  3  Flowerpot Model with Straight Pipe Immediately...used at downstream end of 90-degree elbow. .................... 23  Figure 18. 1:20.377-scale preliminary FPDO model showing 7-ft-long PVC pipe ...27  Figure 23. 1:20.377-scale preliminary model with 1.3 in. lip. The black material at base of pipe was a sealant used to

  16. Clastic Pipes: Proxies of High Water Tables and Strong Ground Motion, Jurassic Carmel Formation, Southern Utah

    NASA Astrophysics Data System (ADS)

    Wheatley, David; Chan, Marjorie

    2015-04-01

    Multiple soft sediment deformation features from bed-scale to basin-scale are well preserved within the Jurassic Carmel Formation of Southern Utah. Field mapping reveals thousands of small-scale clastic injectite pipes (10 cm to 10 m diameter, up to 20 m tall) in extremely high densities (up to 500+ pipes per 0.075 square kilometers). The pipes weather out in positive relief from the surrounding host strata of massive sandstone (sabkha) and crossbedded sands with minor conglomerate and shale (fluvial) deposits. The host rock shows both brittle and ductile deformation. Reverse, normal, and antithetical faulting is common with increased frequency, including ring faults, surrounding the pipes. The pipes formed from liquefaction and subsequent fluidization induced by strong ground motion. Down-dropped, graben blocks and ring faults surrounding pipes indicate initial sediment volume increase during pipe emplacement followed by sediment volume decrease during dewatering. Complex crosscutting relationships indicate several injection events where some pipe events reached the surface as sand blows. Multiple ash layers provide excellent stratigraphic and temporal constraints for the pipe system with the host strata deposited between 166 and 164 Ma. Common volcanic fragments and rounded volcanic cobbles occur within sandstone and conglomerate beds, and pipes. Isolated volcanic clasts in massive sandstone indicate explosive volcanic events that could have been the exogenic trigger for earthquakes. The distribution of pipes are roughly parallel to the Middle Jurassic paleoshoreline located in marginal environments between the shallow epicontinental Sundance Sea and continental dryland. At the vertical stratigraphic facies change from dominantly fluvial sediments to dominantly massive sabkha sediments, there is a 1-2 m-thick floodplain mudstone that was a likely seal for underlying, overpressurized sediments. The combination of loose porous sediment at a critical depth of water saturation made the system extremely susceptible to liquefaction. Fluid inclusions of carbonate nodules present on the pipe margins indicate salinity, temperature, and character of possible early diagenetic fluids before significant burial. These inclusions can reveal information about brines from point sources or fed via groundwater. Overall, the combination of clastic pipes and their related soft deformation structures in the host rock provide proxies for the existence of high water table conditions within arid climate regimes and transitional paleoenvironments previously assumed to be devoid of significant amounts of water. The pipe distribution and evidence of multiple injectite events paralleling an ancient paleoshoreline provides basin-scale insights on repeated paleoseismicity and volcanism along the convergent boundary of the Cordilleran.

  17. 50. PIPING FOR SUBMARINE SECTION, Y&D No. 107728 Scale 3/8' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. PIPING FOR SUBMARINE SECTION, Y&D No. 107728 Scale 3/8' = 1'; August 26, 1929 - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  18. 76 FR 60083 - Carbon and Alloy Seamless Standard, Line, and Pressure Pipe From Japan and Romania

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-28

    ... Alloy Seamless Standard, Line, and Pressure Pipe From Japan and Romania Determinations On the basis of... pressure pipe from Japan and Romania would be likely to lead to continuation or recurrence of material... Seamless Standard, Line, and Pressure Pipe from Japan and Romania: Investigation Nos. 731-TA-847 and 849...

  19. Pore geometry effects on intrapore viscous to inertial flows and on effective hydraulic parameters

    NASA Astrophysics Data System (ADS)

    Chaudhary, Kuldeep; Cardenas, M. Bayani; Deng, Wen; Bennett, Philip C.

    2013-02-01

    In this article, the effects of different diverging-converging pore geometries were investigated, and the microscale fluid flow and effective hydraulic properties from these pores were compared with that of a pipe from viscous to inertial laminar flow regimes. The flow fields are obtained using computational fluid dynamics, and the comparative analysis is based on a new dimensionless hydraulic shape factor β, which is the "specific surface" scaled by the length of pores. Results from all diverging-converging pores show an inverse pattern in velocity and vorticity distributions relative to the pipe flow. The hydraulic conductivity K of all pores is dependent on and can be predicted from β with a power function with an exponent of 3/2. The differences in K are due to the differences in distribution of local friction drag on the pore walls. At Reynolds number (Re) ˜ 0 flows, viscous eddies are found to exist almost in all pores in different sizes, but not in the pipe. Eddies grow when Re → 1 and leads to the failure of Darcy's law. During non-Darcy or Forchheimer flows, the apparent hydraulic conductivity Ka decreases due to the growth of eddies, which constricts the bulk flow region. At Re > 1, the rate of decrease in Ka increases, and at Re >> 1, it decreases to where the change in Ka ≈ 0, and flows once again exhibits a Darcy-type relationship. The degree of nonlinearity during non-Darcy flow decreases for pores with increasing β. The nonlinear flow behavior becomes weaker as β increases to its maximum value in the pipe, which shows no nonlinearity in the flow; in essence, Darcy's law stays valid in the pipe at all laminar flow conditions. The diverging-converging geometry in pores plays a critical role in modifying the intrapore fluid flow, implying that this property should be incorporated in effective larger-scale models, e.g., pore-network models.

  20. Drinking water quality and formation of biofilms in an office building during its first year of operation, a full scale study.

    PubMed

    Inkinen, Jenni; Kaunisto, Tuija; Pursiainen, Anna; Miettinen, Ilkka T; Kusnetsov, Jaana; Riihinen, Kalle; Keinänen-Toivola, Minna M

    2014-02-01

    Complex interactions existing between water distribution systems' materials and water can cause a reduction in water quality and unwanted changes in materials, aging or corrosion of materials and formation of biofilms on surfaces. Substances leaching from pipe materials and water fittings, as well as the microbiological quality of water and formation of biofilms were evaluated by applying a Living Lab theme i.e. a research in a real life setting using a full scale system during its first year of operation. The study site was a real office building with one part of the building lined with copper pipes, the other with cross-linked polyethylene (PEX) pipes thus enabling material comparison; also differences within the cold and hot water systems were analysed. It was found that operational conditions, such as flow conditions and temperature affected the amounts of metals leaching from the pipe network. In particular, brass components were considered to be a source of leaching; e. g. the lead concentration was highest during the first few weeks after the commissioning of the pipe network when the water was allowed to stagnate. Assimilable organic carbon (AOC) and microbially available phosphorus (MAP) were found to leach from PEX pipelines with minor effects on biomass of the biofilm. Cultivable and viable biomass (heterotrophic plate count (HPC), and adenosine triphosphate (ATP)) levels in biofilms were higher in the cold than in the hot water system whereas total microbial biomass (total cell count (DAPI)) was similar with both systems. The type of pipeline material was not found to greatly affect the microbial biomass or Alpha-, Beta- and Gammaproteobacteria profiles (16s rRNA gene copies) after the first one year of operation. Also microbiological quality of water was found to deteriorate due to stagnation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Pipes, Petrol, Paint and Pewter: The Rise and Fall of Lead

    ERIC Educational Resources Information Center

    Peacock, Alan

    2010-01-01

    Lead is a good example of a metal that was used for many things over centuries--in water pipes, paints, on roofs, and in leaded petrol, for example--but was superseded as scientists discovered "new" metals, and because its toxicity became a problem. It was originally an important element in pewter utensils, alloyed with tin; it made the…

  2. Estimating dynamic permeability in fractal pore network saturated by Maxwellian fluid

    NASA Astrophysics Data System (ADS)

    Sun, W.

    2017-12-01

    The frequency dependent flow of fluid in porous media is an important issue in geophysical prospecting. Oscillating flow in pipe leads to frequency dependent dynamic permeability and has been studied in pore network containing Newtonian fluid. But there is little work on oscillating complex fluid in pipe network, especially in irregular network. Here we formulated frequency dependent permeability for Maxwellian fluid and estimated the permeability in three-dimensional fractal network model. We consider an infinitely long cylindrical pipe with rigid solid wall. The pipe is filled with Maxwellian fluids. Based on the mass conservation equation, the equilibrium equation of force and Maxwell constitutive relationship, we formulated the flux by integration of axial velocity component over the pipe's cross section. Then we extend single pipe formulation to a 3D irregular network. Flux balance condition yields a set of linear equations whose unknowns are the fluid pressure at each node. By evaluating the total flow flux through the network, the dynamic permeability can be calculated.We investigated the dynamic permeability of brine and CPyCl/NaSal in a 3D porous sample with a cubic side length 1 cm. The pore network is created by a Voronoi cell filling method. The porosity, i.e., volume ratio between pore/pipe network and the overall cubic, is set as 0.1. The irregular pore network has a fractal structure. The dimension d of the pore network is defined by the relation between node number M within a sphere and the radius r of the sphere,M=rd.The results show that both brine and Maxwellian fluid's permeability maintain a stable value at low frequency, then decreases with fluctuating peaks. The dynamic permeability in pore networks saturated by Maxwellian fluid (CPyCl/NaSal (60 mM)) show larger peaks during the decline process at high frequency, which represents the typical resonance behavior. Dynamic permeability shows clear dependence on the dimension of the fractal network. Small-scale network has higher dimension than large-scale networks. The reason is that in larger networks pore and inter-pore connections are so dense that the probability P(r) to have a neighboring pore at distance r decays faster. The proposed model may be used to explain velocity dispersion in unconventional reservoir rocks observed in laboratory.

  3. CHLORINE DECAY AND BIOFILM STUDIES IN A PILOT SCALE DRINKING WATER DISTRIBUTION DEAD END PIPE SYSTEM

    EPA Science Inventory

    Chlorine decay experiments using a pilot-scale water distribution dead end pipe system were conducted to define relationships between chlorine decay and environmental factors. These included flow rate, biomass concentration and biofilm density, and initial chlorine concentrations...

  4. Composite drill pipe

    DOEpatents

    Leslie, James C [Fountain Valley, CA; Leslie, II, James C.; Heard, James [Huntington Beach, CA; Truong, Liem , Josephson; Marvin, Neubert [Huntington Beach, CA; Hans, [Anaheim, CA

    2008-12-02

    A composite pipe segment is formed to include tapered in wall thickness ends that are each defined by opposed frustoconical surfaces conformed for self centering receipt and intimate bonding contact within an annular space between corresponding surfaces of a coaxially nested set of metal end pieces. The distal peripheries of the nested end pieces are then welded to each other and the sandwiched and bonded portions are radially pinned. The composite segment may include imbedded conductive leads and the axial end portions of the end pieces are shaped to form a threaded joint with the next pipe assembly that includes a contact ring in one pipe assembly pierced by a pointed contact in the other to connect the corresponding leads across the joint.

  5. On the formation, growth, and shapes of solution pipes - insights from numerical modeling

    NASA Astrophysics Data System (ADS)

    Szymczak, Piotr; Tredak, Hanna; Upadhyay, Virat; Kondratiuk, Paweł; Ladd, Anthony J. C.

    2015-04-01

    Cylindrical, vertical structures called solution pipes are a characteristic feature of epikarst, encountered in different parts of the world, both in relatively cold areas such as England and Poland (where their formation is linked to glacial processes) [1] and in coastal areas in tropical or subtropical climate (Bermuda, Australia, South Africa, Caribbean, Mediterranean) [2,3]. They are invariably associated with weakly cemented, porous limestones and relatively high groundwater fluxes. Many of them develop under the colluvial sandy cover and contain the fill of clayey silt. Although it is widely accepted that they are solutional in origin, the exact mechanism by which the flow becomes focused is still under debate. The hypotheses include the concentration of acidified water around stems and roots of plants, or the presence of pre-existing fractures or steeply dipping bedding planes, which would determine the points of entry for the focused groundwater flows. However, there are field sites where neither of this mechanisms was apparently at play and yet the pipes are formed in large quantities [1]. In this communication we show that the systems of solution pipes can develop spontaneously in nearly uniform matrix due to the reactive-infiltration instability: a homogeneous porous matrix is unstable with respect to small variations in local permeability; regions of high permeability dissolve faster because of enhanced transport of reactants, which leads to increased rippling of the front. This leads to the formation of a system of solution pipes which then advance into the matrix. We study this process numerically, by a combination of 2d- and 3d-simulations, solving the coupled flow and transport equations at the Darcy scale. The relative simplicity of this system (pipes developing in a uniform porous matrix, without any pre-existing structure) makes it very attractive from the modeling standpoint. We quantify the factors which control the pipe diameters and the distances between the pipes as well as their growth rates. The most interesting result is the existence of two different regimes of the piped growth, depending on the flow rate. At high flow rates, well-separated, cyllindrical shafts are formed, of a nearly uniform diameter all along their lengths. They advance quickly into the matrix, with velocities several times larger than that of a unperturbed, planar dissolution front. Conversely, for small flow rates, the pipes are funnel-shaped with parabolic tips and their advancement velocity is of the same order as that of a planar front. The transition between the two forms is abrupt, with no intermediate forms observed. The simulation results are compared with field evidence from limestone quarries in Smerdyna, Poland, where several hundred of solution pipes have been exposed. Interestingly, both forms (shaft-like and tunnel-like) are found in the field, sometimes in close proximity to each other. [1] P. Walsh and I. Morawiecka-Zacharz, A dissolution pipe palaeokarst of mid-Pleistocene age preserved in Miocene limestones near Staszow, Poland, Palaeogeogr. Palaeoclimatol. Palaeoecol., 174 (2001), pp. 327-350. [2] K. G. Grimes, Solution pipes and pinnacles in syngenetic karst. In: Gines A., Knez M., Slabe T., Dreybrodt W. (Eds.), Karst Rock Features: Karren Sculpturing. Ljubljana, ZRC Publishing, (2009), pp. 513-523. [3] J. De Waele, S. E. Lauritzen and M. Parise On the formation of dissolution pipes in Quaternary coastal calcareous arenites in Mediterranean settings. Earth. Surf. Proc. Land" 36, (2011), pp. 143-157.

  6. Evidence of arsenic release promoted by disinfection by-products within drinking-water distribution systems.

    PubMed

    Andra, Syam S; Makris, Konstantinos C; Botsaris, George; Charisiadis, Pantelis; Kalyvas, Harris; Costa, Costas N

    2014-02-15

    Changes in disinfectant type could trigger a cascade of reactions releasing pipe-anchored metals/metalloids into finished water. However, the effect of pre-formed disinfection by-products on the release of sorbed contaminants (arsenic-As in particular) from drinking water distribution system pipe scales remains unexplored. A bench-scale study using a factorial experimental design was performed to evaluate the independent and interaction effects of trihalomethanes (TTHM) and haloacetic acids (HAA) on arsenic (As) release from either scales-only or scale-biofilm conglomerates (SBC) both anchored on asbestos/cement pipe coupons. A model biofilm (Pseudomonas aeruginosa) was allowed to grow on select pipe coupons prior experimentation. Either TTHM or HAA individual dosing did not promote As release from either scales only or SBC, detecting <6 μg AsL(-1) in finished water. In the case of scales-only coupons, the combination of the highest spike level of TTHM and HAA significantly (p<0.001) increased dissolved and total As concentrations to levels up to 16 and 95 μg L(-1), respectively. Similar treatments in the presence of biofilm (SBC) resulted in significant (p<0.001) increase in dissolved and total recoverable As up to 20 and 47 μg L(-1), respectively, exceeding the regulatory As limit. Whether or not, our laboratory-based results truly represent mechanisms operating in disinfected finished water in pipe networks remains to be investigated in the field. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Impact of the lithographic discontinuities on the karst conduit development - insights from modelling

    NASA Astrophysics Data System (ADS)

    Petrus, Karine; Szymczak, Piotr

    2016-04-01

    Karst formation is controlled by the processes of the fluid flow and reactant transport coupled to the chemical erosion of the limestone rock [1]. The coupling between these processes can lead to a number of different instabilities, resulting in the formation of dissolutional voids, caverns and conduits. Arguably the simplest systems of this kind are solution pipes, in which gravitationally driven water movement carves vertical conduits in limestone rocks. In the homogeneous rocks these conduits are often cylindrical, with almost a constant diameter along their length. However, in a stratified medium, the morphology of the pipes changes. For example, if a number of less porous layers is introduced in an otherwise homogeneous medium, then the pipes are observed to narrow as they cross the layers and then widen up to form bulbous caverns as they emerge from the layer [1]. In this communication, we investigate these effects more closely, considering different kind of lithographic discontinuities to be present in the system: the layers of increased/decreased porosity and/or permeability as well as the solubility which is different from the rest of the system. Using a Darcy-scale numerical model we analyze the effects these layers have on the shape and growth of solution pipes and compare the results on the piping morphologies observed in nature. Finally we comment on the possible relevance of these results to the cave-formation phenomena and the inception horizon concept [3]. References: 1.Howard A. D., The development of karst features, Bull. Natl. Spel. Soc. 25, 45-65 (1963) 2. Petrus, K. and Szymczak, P., Influence of layering on the formation and growth of solution pipes. Frontiers in Physics (submitted) 3.Filipponi , M., Jeannin, P. and Tacher, L., Evidence of inception horizons in karst conduit networks, Geomorphology, 106, 86-99 (2009)

  8. CaSO4 Scale Formation on Vibrated Piping System in the Presence Citric Acid

    NASA Astrophysics Data System (ADS)

    Mangestiyono, W.; Jamari, J.; Muryanto, S.; Bayuseno, A. P.

    2018-02-01

    Vibration in many industries commonly generated by the operation mechanical equipment such as extruder, mixer, blower, compressor, turbine, generator etc. Vibration propagates into the floor and attacks the pipe around those mechanical equipment. In this paper, the influence of vibration in a pipe on the CaSO4 scale formation was investigated to understand the effect of vibration on the kinetics, mass of scale, crystal phases and crystal polymorph. To generate vibration force, mechanical equipment was prepared consisted of electrical motor, crankshaft, connecting rod and a vibration table at where test pipe section mounted. Deposition rate increased significantly when the vibration affected to the system i.e. 0.5997 and 1.6705 gr/hr for vibration frequency 4.00 and 8.00 Hz. The addition 10.00 ppm of citric acid declined the deposition rate of 8 Hz experiment from 3.4599 gr/hr to 2.2865 gr/hr.

  9. Flint Water Crisis Caused By Interrupted Corrosion Control: Investigating "Ground Zero" Home.

    PubMed

    Pieper, Kelsey J; Tang, Min; Edwards, Marc A

    2017-02-21

    Flint, Michigan switched to the Flint River as a temporary drinking water source without implementing corrosion control in April 2014. Ten months later, water samples collected from a Flint residence revealed progressively rising water lead levels (104, 397, and 707 μg/L) coinciding with increasing water discoloration. An intensive follow-up monitoring event at this home investigated patterns of lead release by flow rate-all water samples contained lead above 15 μg/L and several exceeded hazardous waste levels (>5000 μg/L). Forensic evaluation of exhumed service line pipes compared to water contamination "fingerprint" analysis of trace elements, revealed that the immediate cause of the high water lead levels was the destabilization of lead-bearing corrosion rust layers that accumulated over decades on a galvanized iron pipe downstream of a lead pipe. After analysis of blood lead data revealed spiking lead in blood of Flint children in September 2015, a state of emergency was declared and public health interventions (distribution of filters and bottled water) likely averted an even worse exposure event due to rising water lead levels.

  10. Effects of sulfate on heavy metal release from iron corrosion scales in drinking water distribution system.

    PubMed

    Sun, Huifang; Shi, Baoyou; Yang, Fan; Wang, Dongsheng

    2017-05-01

    Trace heavy metals accumulated in iron corrosion scales within a drinking water distribution system (DWDS) could potentially be released to bulk water and consequently deteriorate the tap water quality. The objective of this study was to identify and evaluate the release of trace heavy metals in DWDS under changing source water conditions. Experimental pipe loops with different iron corrosion scales were set up to simulate the actual DWDS. The effects of sulfate levels on heavy metal release were systemically investigated. Heavy metal releases of Mn, Ni, Cu, Pb, Cr and As could be rapidly triggered by sulfate addition but the releases slowly decreased over time. Heavy metal release was more severe in pipes transporting groundwater (GW) than in pipes transporting surface water (SW). There were strong positive correlations (R 2  > 0.8) between the releases of Fe and Mn, Fe and Ni, Fe and Cu, and Fe and Pb. When switching to higher sulfate water, iron corrosion scales in all pipe loops tended to be more stable (especially in pipes transporting GW), with a larger proportion of stable constituents (mainly Fe 3 O 4 ) and fewer unstable compounds (β-FeOOH, γ-FeOOH, FeCO 3 and amorphous iron oxides). The main functional iron reducing bacteria (IRB) communities were favorable for the formation of Fe 3 O 4 . The transformation of corrosion scales and the growth of sulfate reducing bacteria (SRB) accounted for the gradually reduced heavy metal release with time. The higher metal release in pipes transporting GW could be due to increased Fe 6 (OH) 12 CO 3 content under higher sulfate concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Experimental simulation of latent heat thermal energy storage and heat pipe thermal transport for dish concentrator solar receiver

    NASA Technical Reports Server (NTRS)

    Narayanan, R.; Zimmerman, W. F.; Poon, P. T. Y.

    1981-01-01

    Test results on a modular simulation of the thermal transport and heat storage characteristics of a heat pipe solar receiver (HPSR) with thermal energy storage (TES) are presented. The HPSR features a 15-25 kWe Stirling engine power conversion system at the focal point of a parabolic dish concentrator operating at 827 C. The system collects and retrieves solar heat with sodium pipes and stores the heat in NaF-MgF2 latent heat storage material. The trials were run with a single full scale heat pipe, three full scale TES containers, and an air-cooled heat extraction coil to replace the Stirling engine heat exchanger. Charging and discharging, constant temperature operation, mixed mode operation, thermal inertial, etc. were studied. The heat pipe performance was verified, as were the thermal energy storage and discharge rates and isothermal discharges.

  12. OTEC Cold Water Pipe-Platform Subsystem Dynamic Interaction Validation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Varley, Robert; Halkyard, John; Johnson, Peter

    A commercial floating 100-megawatt (MW) ocean thermal energy conversion (OTEC) power plant will require a cold water pipe (CWP) with a diameter of 10-meter (m) and length of up to 1,000 m. The mass of the cold water pipe, including entrained water, can exceed the mass of the platform supporting it. The offshore industry uses software-modeling tools to develop platform and riser (pipe) designs to survive the offshore environment. These tools are typically validated by scale model tests in facilities able to replicate real at-sea meteorological and ocean (metocean) conditions to provide the understanding and confidence to proceed to finalmore » design and full-scale fabrication. However, today’s offshore platforms (similar to and usually larger than those needed for OTEC applications) incorporate risers (or pipes) with diameters well under one meter. Secondly, the preferred construction method for large diameter OTEC CWPs is the use of composite materials, primarily a form of fiber-reinforced plastic (FRP). The use of these material results in relatively low pipe stiffness and large strains compared to steel construction. These factors suggest the need for further validation of offshore industry software tools. The purpose of this project was to validate the ability to model numerically the dynamic interaction between a large cold water-filled fiberglass pipe and a floating OTEC platform excited by metocean weather conditions using measurements from a scale model tested in an ocean basin test facility.« less

  13. Elimination of Acid Cleaning of High Temperature Salt Water Heat Exchangers: Redesigned Pre-Production Full-Scale Heat Pipe Bleed Air Cooler for Shipboard Evaluation

    DTIC Science & Technology

    2011-11-01

    Cleaning of High Temperature Salt Water Heat Exchangers ESTCP WP-200302 Subtitle: Redesigned Pre-production Full-Scale Heat Pipe Bleed Air Cooler For...FINAL 3. DATES COVERED (From - To) 1-Jan-2003 – 1-Oct-2009 4. TITLE AND SUBTITLE Elimination of Acid Cleaning of High Temperature Salt Water Heat...6-5 Figure 6- 6 HP-BAC Tube Sheet Being Immersed in Ultrasonic Cleaning Tank ..................................... 6-6 Figure 6- 7 Heat Pipe

  14. Experimental study of Siphon breaker about size effect in real scale reactor design

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kang, S. H.; Ahn, H. S.; Kim, J. M.

    2012-07-01

    Rupture accident within the pipe of a nuclear reactor is one of the main causes of a loss of coolant accident (LOCA). Siphon-breaking is a passive method that can prevent a LOCA. In this study, either a line or a hole is used as a siphon-breaker, and the effect of various parameters, such as the siphon-breaker size, pipe rupture point, pipe rupture size, and the presence of an orifice, are investigated using an experimental facility similar in size to a full-scale reactor. (authors)

  15. Multiphase numerical analysis of heat pipe with different working fluids for solar applications

    NASA Astrophysics Data System (ADS)

    Aswath, S.; Netaji Naidu, V. H.; Padmanathan, P.; Raja Sekhar, Y.

    2017-11-01

    Energy crisis is a prognosis predicted in many cases with the indiscriminate encroachment of conventional energy sources for applications on a massive scale. This prediction, further emboldened by the marked surge in global average temperatures, attributed to climate change and global warming, the necessity to conserve the environment and explore alternate sources of energy is at an all-time high. Despite being among the lead candidates for such sources, solar energy is utilized far from its vast potential possibilities due to predominant economic constraints. Even while there is a growing need for solar panels at more affordable rates, the other options to harness better out of sun’s energy is to optimize and improvise existing technology. One such technology is the heat pipe used in Evacuated Tube Collectors (ETC). The applications of heat pipe have been gaining momentum in various fields since its inception and substantial volumes of research have explored optimizing and improving the technology which is proving effective in heat recovery and heat transfer better than conventional systems. This paper carries out a computational analysis on a comparative simulation between two working fluids within heat pipe of same geometry. It further endeavors to study the multiphase transitions within the heat pipe. The work is carried out using ANSYS Fluent with inputs taken from solar data for the location of Vellore, Tamil Nadu. A wickless, gravity-assisted heat pipe (GAHP) is taken for the simulation. Water and ammonia are used as the working fluids for comparative multiphase analysis to arrive at the difference in heat transfer at the condenser section. It is demonstrated that a heat pipe ETC with ammonia as working fluid showed higher heat exchange (temperature difference) as against that of water as working fluid. The multiphase model taken aided in study of phase transitions within both cases and supported the result of ammonia as fluid being a better candidate.

  16. PROCESS WATER BUILDING, TRA605. AERIAL TAKEN WHILE SEVERAL PIPE TRENCHES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PROCESS WATER BUILDING, TRA-605. AERIAL TAKEN WHILE SEVERAL PIPE TRENCHES REMAINED OPEN. CAMERA FACES EASTERLY. NOTE DUAL PIPES BETWEEN REACTOR BUILDING AND NORTH SIDE OF PROCESS WATER BUILDING. PIPING NEAR WORKING RESERVOIR HEADS FOR RETENTION RESERVOIR. PIPE FROM DEMINERALIZER ENTERS MTR FROM NORTH. SEE ALSO TRENCH FOR COOLANT AIR DUCT AT SOUTH SIDE OF MTR AND LEADING TO FAN HOUSE AND STACK. INL NEGATIVE NO. 2966-A. Unknown Photographer, 7/31/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  17. 76 FR 19788 - Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-08

    ...)] Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand Determinations On... fittings from Brazil, China, Japan, Taiwan, and Thailand would be likely to lead to continuation or... Pipe Fittings from Brazil, China, Japan, Taiwan, and Thailand: Investigation Nos. 731-TA-308-310 and...

  18. Internal erosion during soil pipe flow: Role in gully erosion and hillslope instability

    USDA-ARS?s Scientific Manuscript database

    Many field observations have lead to speculation on the role of piping in embankment failures, landslides, and gully erosion. However, there has not been a consensus on the subsurface flow and erosion processes involved and inconsistent use of terms have exasperated the problem. One such piping proc...

  19. 24 CFR 3280.605 - Joints and connections.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of the fitting. Plastic pipe and copper tubing shall be inserted to the full depth of the solder cup..., cutting oil and foreign matter shall be removed. Pipe joint cement or thread lubricant shall be of... connected to a public water system, made with solder having not more than 0.2 percent lead. (4) Plastic pipe...

  20. 24 CFR 3280.605 - Joints and connections.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of the fitting. Plastic pipe and copper tubing shall be inserted to the full depth of the solder cup..., cutting oil and foreign matter shall be removed. Pipe joint cement or thread lubricant shall be of... connected to a public water system, made with solder having not more than 0.2 percent lead. (4) Plastic pipe...

  1. 75 FR 76025 - Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... INTERNATIONAL TRADE COMMISSION [Investigation Nos. 731-TA-376 and 563-564 (Third Review)] Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan AGENCY: United States International... steel butt-weld pipe fittings from Japan, Korea, and Taiwan would be likely to lead to continuation or...

  2. 24 CFR 3280.605 - Joints and connections.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of the fitting. Plastic pipe and copper tubing shall be inserted to the full depth of the solder cup... connected to a public water system, made with solder having not more than 0.2 percent lead. (4) Plastic pipe, fittings and joints. Plastic pipe and fittings shall be joined by installation methods recommended by the...

  3. 46 CFR 92.20-50 - Heating and cooling.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) under normal operating conditions without curtailing ventilation. (c) Radiators and other heating... the occupants. Pipes leading to radiators or heating apparatus must be insulated where those pipes...

  4. Passive advection-dispersion in networks of pipes: Effect of connectivity and relationship to permeability

    NASA Astrophysics Data System (ADS)

    Bernabé, Y.; Wang, Y.; Qi, T.; Li, M.

    2016-02-01

    The main purpose of this work is to investigate the relationship between passive advection-dispersion and permeability in porous materials presumed to be statistically homogeneous at scales larger than the pore scale but smaller than the reservoir scale. We simulated fluid flow through pipe network realizations with different pipe radius distributions and different levels of connectivity. The flow simulations used periodic boundary conditions, allowing monitoring of the advective motion of solute particles in a large periodic array of identical network realizations. In order to simulate dispersion, we assumed that the solute particles obeyed Taylor dispersion in individual pipes. When a particle entered a pipe, a residence time consistent with local Taylor dispersion was randomly assigned to it. When exiting the pipe, the particle randomly proceeded into one of the pipes connected to the original one according to probabilities proportional to the outgoing volumetric flow in each pipe. For each simulation we tracked the motion of at least 6000 solute particles. The mean fluid velocity was 10-3 ms-1, and the distance traveled was on the order of 10 m. Macroscopic dispersion was quantified using the method of moments. Despite differences arising from using different types of lattices (simple cubic, body-centered cubic, and face-centered cubic), a number of general observations were made. Longitudinal dispersion was at least 1 order of magnitude greater than transverse dispersion, and both strongly increased with decreasing pore connectivity and/or pore size variability. In conditions of variable hydraulic radius and fixed pore connectivity and pore size variability, the simulated dispersivities increased as power laws of the hydraulic radius and, consequently, of permeability, in agreement with previously published experimental results. Based on these observations, we were able to resolve some of the complexity of the relationship between dispersivity and permeability.

  5. Boomwhackers and End-Pipe Corrections

    NASA Astrophysics Data System (ADS)

    Ruiz, Michael J.

    2014-02-01

    End-pipe corrections seldom come to mind as a suitable topic for an introductory physics lab. Yet, the end-pipe correction formula can be verified in an engaging and inexpensive lab that requires only two supplies: plastic-tube toys called boomwhackers and a meterstick. This article describes a lab activity in which students model data from plastic tubes to arrive at the end-correction formula for an open pipe. Students also learn the basic mathematics behind the musical scale, and come to appreciate the importance of end-pipe physics in the engineering design of toy musical tubes.

  6. Guided wave technique for non-destructive testing of StifPipe

    NASA Astrophysics Data System (ADS)

    Amjad, Umar; Yadav, Susheel K.; Nguyen, Chi H.; Ehsani, Mohammad; Kundu, Tribikram

    2015-03-01

    The newly-developed StifPipe® is an effective technology for repair and strengthening of existing pipes and culverts. The wall of this pipe consists of a lightweight honeycomb core with carbon or glass fiber reinforced polymer (FRP) applied to the skin. The presence of the hollow honeycomb introduces challenges in the nondestructive testing (NDT) of this pipe. In this study, it is investigated if guided waves, excited by PZT (Lead ZirconateTitanate) transducer can detect damages in the honeycomb layer of the StifPipe®. Multiple signal processing techniques are used for in-depth study and understanding of the recorded signals. The experimental technique for damage detection in StifPipe® material is described and the obtained results are presented in this paper.

  7. (Congressional Add) Partnership in Innovative Preparation for Educators and Students (PIPES)

    DTIC Science & Technology

    2011-12-30

    researchers collected and analyzed both qualitative and quantitative data from students, teachers, and parents related to PIPES program effectiveness...years. PIPES researchers collected and analyzed both qualitative and quantitative data from students, teachers, and parents related to PIPES program...reported an internal reliability of .93 at pretest and .95 at posttest and follow-up. We used a six point scale "not at all true" to "definitely

  8. Building a Copper Pipe "Xylophone."

    ERIC Educational Resources Information Center

    Lapp, David R.

    2003-01-01

    Explains how to use the equation for frequency of vibration of a transversely oscillating bar or pipe with both ends free to vibrate to build a simple and inexpensive xylophone from a 3-meter section of copper pipe. The instrument produces a full major scale and can be used to investigate various musical intervals. (Author/NB)

  9. Mathematical model of polyethylene pipe bending stress state

    NASA Astrophysics Data System (ADS)

    Serebrennikov, Anatoly; Serebrennikov, Daniil

    2018-03-01

    Introduction of new machines and new technologies of polyethylene pipeline installation is usually based on the polyethylene pipe flexibility. It is necessary that existing bending stresses do not lead to an irreversible polyethylene pipe deformation and to violation of its strength characteristics. Derivation of the mathematical model which allows calculating analytically the bending stress level of polyethylene pipes with consideration of nonlinear characteristics is presented below. All analytical calculations made with the mathematical model are experimentally proved and confirmed.

  10. Numerical investigation of the influence of electromagnetic treatment on calcium carbonate scaling rate in non-isothermal pipe flow

    NASA Astrophysics Data System (ADS)

    Kireev, Victor; Kovaleva, Liana; Isakov, Andrey; Alimbekova, Sofya

    2017-11-01

    In the present paper, an attempt to explain the mechanisms of the electromagnetic field influence on the process of formation and deposition of calcium carbonate from supersaturated brine solution has been made using numerical modeling. The one-dimensional mathematical model of the brine laminar flow through a cylindrical tube with non-uniform temperature field is written in the form of the system of transient convection-diffusion-reaction partial differential equations describing temperature field and chemical components concentrations (Ca2+, HCO3-, CaCO3). The influence of the temperature on the kinetics of formation of calcium carbonate is taken into account and it is described in accordance with the Arrhenius equation. The kinetics of the calcium carbonate precipitation on the wall of the pipe is given on the basis of the Henry isotherm. It has been established that the electromagnetic treatment of brine solution leads to a decrease of the adsorption rate constant and Henry's constant but it does not significantly influence on the chemical reaction rate of calcium carbonate formation. It also has been shown that treatment with electromagnetic field significantly reduces the amount of calcium carbonate deposits on the wall of the pipe.

  11. 46 CFR 32.40-50 - Heating and cooling-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) under normal operating conditions without curtailing ventilation. (c) Radiators and other heating... the occupants. Pipes leading to radiators or heating apparatus must be insulated where those pipes...

  12. 78 FR 42546 - Light-Walled Rectangular Pipe and Tube From China, Korea, Mexico, and Turkey: Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-16

    ...-Walled Rectangular Pipe and Tube From China, Korea, Mexico, and Turkey: Notice of Commission... light-walled rectangular pipe and tube from China, Korea, Mexico, and Turkey would be likely to lead to... institution from the Government of Turkey, the Commission found that the respondent interested party group...

  13. Research on the ITOC based scheduling system for ship piping production

    NASA Astrophysics Data System (ADS)

    Li, Rui; Liu, Yu-Jun; Hamada, Kunihiro

    2010-12-01

    Manufacturing of ship piping systems is one of the major production activities in shipbuilding. The schedule of pipe production has an important impact on the master schedule of shipbuilding. In this research, the ITOC concept was introduced to solve the scheduling problems of a piping factory, and an intelligent scheduling system was developed. The system, in which a product model, an operation model, a factory model, and a knowledge database of piping production were integrated, automated the planning process and production scheduling. Details of the above points were discussed. Moreover, an application of the system in a piping factory, which achieved a higher level of performance as measured by tardiness, lead time, and inventory, was demonstrated.

  14. Flowpath evaluation and reconnaissance by remote field Eddy current testing (FERRET)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smoak, A.E.; Zollinger, W.T.

    1993-12-31

    This document describes the design and development of FERRET (Flowpath Evaluation and Reconnaisance by Remote-field Eddy current Testing). FERRET is a system for inspecting the steel pipes which carry cooling water to underground nuclear waste storage tanks. The FERRET system has been tested in a small scale cooling pipe mock-up, an improved full scale mock-up, and in flaw detection experiments. Early prototype designs of FERRET and the FERRET launcher (a device which inserts, moves, and retrieves probes from a piping system) as well as the field-ready design are discussed.

  15. The cleaning method selected for new PEX pipe installation can affect short-term drinking water quality.

    PubMed

    Kelley, Keven M; Stenson, Alexandra C; Cooley, Racheal; Dey, Rajarashi; Whelton, Andrew J

    2015-12-01

    The influence of four different cleaning methods used for newly installed polyethylene (PEX) pipes on chemical and odor quality was determined. Bench-scale testing of two PEX (type b) pipe brands showed that the California Plumbing Code PEX installation method does not maximize total organic carbon (TOC) removal. TOC concentration and threshold odor number values significantly varied between two pipe brands. Different cleaning methods impacted carbon release, odor, as well the level of drinking water odorant ethyl tert-butyl ether. Both pipes caused odor values up to eight times greater than the US federal drinking water odor limit. Unique to this project was that organic chemicals released by PEX pipe were affected by pipe brand, fill/empty cycle frequency, and the pipe cleaning method selected by the installer.

  16. Modeling of transient heat pipe operation

    NASA Technical Reports Server (NTRS)

    Colwell, Gene T.

    1989-01-01

    Mathematical models and an associated computer program for heat pipe startup from the frozen state have been developed. Finite element formulations of the governing equations are written for each heat pipe region for each operating condition during startup from the frozen state. The various models were checked against analytical and experimental data available in the literature for three specific types of operation. Computations using the methods developed were made for a space shuttle reentry mission where a heat pipe cooled leading edge was used on the wing.

  17. Flow and evaporation in single micrometer and nanometer scale pipes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Velasco, A. E.; Yang, C.; Siwy, Z. S.

    2014-07-21

    We report measurements of pressure driven flow of fluids entering vacuum through a single pipe of micrometer or nanometer scale diameter. Nanopores were fabricated by etching a single ion track in polymer or mica foils. A calibrated mass spectrometer was used to measure the flow rates of nitrogen and helium through pipes with diameter ranging from 10 μm to 31 nm. The flow of gaseous and liquid nitrogen was studied near 77 K, while the flow of helium was studied from the lambda point (2.18 K) to above the critical point (5.2 K). Flow rates were controlled by changing the pressure drop across the pipemore » in the range 0–31 atm. When the pressure in the pipe reached the saturated vapor pressure, an abrupt flow transition was observed. A simple viscous flow model is used to determine the position of the liquid/vapor interface in the pipe. The observed mass flow rates are consistent with no slip boundary conditions.« less

  18. Measurements of the wall-normal velocity component in very high Reynolds number pipe flow

    NASA Astrophysics Data System (ADS)

    Vallikivi, Margit; Hultmark, Marcus; Smits, Alexander J.

    2012-11-01

    Nano-Scale Thermal Anemometry Probes (NSTAPs) have recently been developed and used to study the scaling of the streamwise component of turbulence in pipe flow over a very large range of Reynolds numbers. This probe has an order of magnitude higher spatial and temporal resolution than regular hot wires, allowing it to resolve small scale motions at very high Reynolds numbers. Here use a single inclined NSTAP probe to study the scaling of the wall normal component of velocity fluctuations in the same flow. These new probes are calibrated using a method that is based on the use of the linear stress region of a fully developed pipe flow. Results on the behavior of the wall-normal component of velocity for Reynolds numbers up to 2 million are reported. Supported under NR Grant N00014-09-1-0263 (program manager Ron Joslin) and NSF Grant CBET-1064257 (program manager Henning Winter).

  19. Water-quality data collected to determine the presence, source, and concentration of lead in the drinking water supply at Pipe Spring National Monument, northern Arizona

    USGS Publications Warehouse

    Macy, Jamie P.; Sharrow, David; Unema, Joel

    2013-01-01

    Pipe Spring National Monument in northern Arizona contains historically significant springs. The groundwater source of these springs is the same aquifer that presently is an important source of drinking water for the Pipe Spring National Monument facilities, the Kaibab Paiute Tribe, and the community of Moccasin. The Kaibab Paiute Tribe monitored lead concentrations from 2004 to 2009; some of the analytical results exceeded the U.S. Environmental Protection Agency action level for treatment technique for lead of 15 parts per billion. The National Park Service and the Kaibab Paiute Tribe were concerned that the local groundwater system that provides the domestic water supply might be contaminated with lead. Lead concentrations in water samples collected by the U.S. Geological Survey from three springs, five wells, two water storage tanks, and one faucet were less than the U.S. Environmental Protection Agency action level for treatment technique. Lead concentrations of rock samples representative of the rock units in which the local groundwater resides were less than 22 parts per million.

  20. Combining geomorphological mapping and near surface geophysics (GPR and ERT) to study piping systems

    NASA Astrophysics Data System (ADS)

    Bernatek-Jakiel, Anita; Kondracka, Marta

    2016-12-01

    This paper aims to provide a more comprehensive characterization of piping systems in mountainous areas under a temperate climate using geomorphological mapping and geophysical methods (electrical resistivity tomography - ERT and ground penetrating radar - GPR). The significance of piping in gully formation and hillslope hydrology has been discussed for many years, and most of the studies are based on surface investigations. However, it seems that most surface investigations underestimate this subsurface process. Therefore, our purpose was to estimate the scale of piping activity based on both surface and subsurface investigations. We used geophysical methods to detect the boundary of lateral water movement fostering pipe development and recognize the internal structure of the underlying materials. The survey was carried out in the Bereźnica Wyżna catchment, in the Bieszczady Mountains. (Eastern Carpathians, Poland), where pipes develop in Cambisols at a mean depth of about 0.7-0.8 m. The geophysical techniques that were used are shown to be successful in identifying pipes. GPR data suggest that the density of piping systems is much larger than that detectible from surface observations alone. Pipe length can be > 6.5-9.2% (maximum = 49%) higher than what surface mapping suggests. Thus, the significance of piping in hillslope hydrology and gully formation can be greater than previously assumed. These results also draw attention to the scale of piping activity in the Carpathians, where this process has been neglected for many years. The ERT profiles reveal areas affected by piping as places of higher resistivity values, which are an effect of a higher content of air-filled pores (due to higher soil porosity, intense biological activity, and well-developed soil structure). In addition, the ERT profiles show that the pipes in the study area develop at the soil-bedrock interface, probably above the layers of shales or mudstones which create a water restrictive layer. Our results illustrate the suitability and limitations of GPR and ERT to study soil piping. In general, geophysical surveying is useful for gathering more information on pipe density, potential pipe detection, and recognition of the internal structure of materials underlying the pipes. However, the interpretation of radargrams and ERT profiles should be always accompanied by detailed terrain mapping due to potential disturbances affecting geophysical profiles.

  1. Turbulence scalings in pipe flows exhibiting polymer-induced drag reduction

    NASA Astrophysics Data System (ADS)

    Zadrazil, Ivan; Markides, Christos

    2014-11-01

    Non-intrusive laser based diagnostics technique, namely Particle Image Velocimetry, was used to in detail characterise polymer induced drag reduction in a turbulent pipe flow. The effect of polymer additives was investigated in a pneumatically-driven flow facility featuring a horizontal pipe test section of inner diameter 25.3 mm and length 8 m. Three high molecular weight polymers (2, 4 and 8 MDa) at concentrations of 5 - 250 wppm were used at Reynolds numbers from 35000 to 210000. The PIV derived results show that the level of drag reduction scales with different normalised turbulence parameters, e.g. streamwise and spanwise velocity fluctuations, vorticity or Reynolds stresses. These scalings are dependent of the distance from the wall, however, are independent of the Reynolds numbers range investigated.

  2. Pipe connector

    DOEpatents

    Sullivan, Thomas E.; Pardini, John A.

    1978-01-01

    A safety test facility for testing sodium-cooled nuclear reactor components includes a reactor vessel and a heat exchanger submerged in sodium in the tank. The reactor vessel and heat exchanger are connected by an expansion/deflection pipe coupling comprising a pair of coaxially and slidably engaged tubular elements having radially enlarged opposed end portions of which at least a part is of spherical contour adapted to engage conical sockets in the ends of pipes leading out of the reactor vessel and in to the heat exchanger. A spring surrounding the pipe coupling urges the end portions apart and into engagement with the spherical sockets. Since the pipe coupling is submerged in liquid a limited amount of leakage of sodium from the pipe can be tolerated.

  3. Scaling of an Optically Pumped Mid-Infrared Rubidium Laser

    DTIC Science & Technology

    2015-03-26

    v AFIT-ENP-MS-15-M-104 Abstract An optically pumped mid-infrared rubidium (Rb) pulsed laser has been demonstrated in a heat pipe ... Heat Pipe Assembly ........................................................................................12 Figure 3.3. Rb Number Density vs. Heat ...the first experiments that used a heat pipe as the gain cell. This experiment would influence the work of Sharma (Sharma, 1981:210). 9 Krupke

  4. Improvement of the thermal and mechanical flow characteristics in the exhaust system of piston engine through the use of ejection effect

    NASA Astrophysics Data System (ADS)

    Plotnikov, L. V.; Zhilkin, B. P.; Brodov, Yu M.

    2017-11-01

    The results of experimental research of gas dynamics and heat transfer in the exhaust process in piston internal combustion engines are presented. Studies were conducted on full-scale models of piston engine in the conditions of unsteady gas-dynamic (pulsating flows). Dependences of the instantaneous flow speed and the local heat transfer coefficient from the crankshaft rotation angle in the exhaust pipe are presented in the article. Also, the flow characteristics of the exhaust gases through the exhaust systems of various configurations are analyzed. It is shown that installation of the ejector in the exhaust system lead to a stabilization of the flow and allows to improve cleaning of the cylinder from exhaust gases and to optimize the thermal state of the exhaust pipes. Experimental studies were complemented by numerical simulation of the working process of the DM-21 diesel engine (production of “Ural diesel-motor plant”). The object of modeling was the eight-cylinder diesel with turbocharger. The simulation was performed taking into account the processes nonstationarity in the intake and exhaust pipes for the various configurations of exhaust systems (with and without ejector). Numerical simulation of the working process of diesel was performed in ACTUS software (ABB Turbo Systems). The simulation results confirmed the stabilization of the flow due to the use of the ejection effect in the exhaust system of a diesel engine. The use of ejection in the exhaust system of the DM-21 diesel leads to improvement of cleaning cylinders up to 10 %, reduces the specific fuel consumption on average by 1 %.

  5. Study of Strain-Stress Behavior of Non-Pressure Reinforced Concrete Pipes Used in Road Building

    NASA Astrophysics Data System (ADS)

    Rakitin, B. A.; Pogorelov, S. N.; Kolmogorova, A. O.

    2017-11-01

    The article contains the results of the full-scale tests performed for special road products - large-diameter non-pressure concrete pipes reinforced with a single space cylindrical frame manufactured with the technology of high-frequency vertical vibration molding with an immediate demolding. The authors studied the change in the strain-stress behavior of reinforced concrete pipes for underground pipeline laying depending on their laying depth in the trench and the transport load considering the properties of the surrounding ground mass. The strain-stress behavior of the reinforced concrete pipes was evaluated using the strain-gauge method based on the application of active resistance strain gauges. Based on the completed research, the authors made a conclusion on the applicability of a single space frame for reinforcement of large-diameter non-pressure concrete pipes instead of a double frame which allows one to significantly reduce the metal consumption for the production of one item. As a result of the full-scale tests of reinforced concrete pipes manufactured by vertical vibration molding, the authors obtained new data on the deformation of a pipeline cross-section depending on the placement of the transport load with regard to the axis.

  6. Triaxial Permeability Device

    DTIC Science & Technology

    1988-01-01

    potential for particle migration which can lead to piping, clogging, or hydraulic fracturing . Since the chemical conductivity under the high gradient...U~ .. .. - > 63 consolidation or expansion, it may be concluded that this gradient did not cause piping, clogging, or hydraulic fracturing for

  7. Spacecraft Crew Cabin Condensation Control

    NASA Technical Reports Server (NTRS)

    Carrillo, Laurie Y.; Rickman, Steven L.; Ungar, Eugene K.

    2013-01-01

    A report discusses a new technique to prevent condensation on the cabin walls of manned spacecraft exposed to the cold environment of space, as such condensation could lead to free water in the cabin. This could facilitate the growth of mold and bacteria, and could lead to oxidation and weakening of the cabin wall. This condensation control technique employs a passive method that uses spacecraft waste heat as the primary wallheating mechanism. A network of heat pipes is bonded to the crew cabin pressure vessel, as well as the pipes to each other, in order to provide for efficient heat transfer to the cabin walls and from one heat pipe to another. When properly sized, the heat-pipe network can maintain the crew cabin walls at a nearly uniform temperature. It can also accept and distribute spacecraft waste heat to maintain the pressure vessel above dew point.

  8. Effects of Urban Stormwater Infrastructure and Spatial Scale on Nutrient Export and Runoff from Semi-Arid Urban Catchments

    NASA Astrophysics Data System (ADS)

    Hale, R. L.; Turnbull, L.; Earl, S.; Grimm, N. B.

    2011-12-01

    There has been an abundance of literature on the effects of urbanization on downstream ecosystems, particularly due to changes in nutrient inputs as well as hydrology. Less is known, however, about nutrient transport processes and processing in urban watersheds. Engineered drainage systems are likely to play a significant role in controlling the transport of water and nutrients downstream, and variability in these systems within and between cities may lead to differences in the effects of urbanization on downstream ecosystems over time and space. We established a nested stormwater sampling network with 12 watersheds ranging in scale from 5 to 17000 ha in the Indian Bend Wash watershed in Scottsdale, AZ. Small (<200ha) watersheds had uniform land cover (medium density residential), but were drained by a variety of stormwater infrastructure including surface runoff, pipes, natural or modified washes, and retention basins. At the outlet of each of these catchments we monitored rainfall and discharge, and sampled stormwater throughout runoff events for dissolved nitrogen (N), phosphorus (P), and organic carbon (oC). Urban stormwater infrastructure is characterized by a range of hydrologic connectivity. Piped watersheds are highly connected and runoff responds linearly to rainfall events, in contrast to watersheds drained with retention basins and washes, where runoff exhibits a nonlinear threshold response to rainfall events. Nutrient loads from piped watersheds scale linearly with total storm rainfall. Because of frequent flushing, nutrient concentrations from these sites are lower than from wash and retention basin drained sites and total nutrient loads exhibit supply limitation, e.g., nutrient loads are poorly predicted by storm rainfall and are strongly controlled by factors that determine the amount of nutrients stored within the watershed, such as antecedent dry days. In contrast, wash and retention basin-drained watersheds exhibit transport limitation. These watersheds flow less frequently than pipe-drained sites and therefore stormwater has higher concentrations of nutrients, although total loads are significantly lower. Nonlinearities in cross-storm rainfall-nutrient loading relationships for the wash and retention basin watersheds suggest that these systems may become supply limited during large rain events. Results show that characteristics of the hydrologic network such as hydrologic connectivity mediate terrestrial-aquatic linkages. Specifically, we see that increased hydrologic connectivity, as in the piped watershed, actually decreases the predictive power of storm size with regard to nutrient export, whereas nutrient loads from poorly connected watersheds are strongly predicted by storm size.

  9. Venus: No Breaks from an Extended Childhood

    NASA Astrophysics Data System (ADS)

    Moore, W. B.; Kankanamge, D. G. J.

    2017-05-01

    High surface temperatures lead to lower heat flow and lower stress as planets transition out of the heat-pipe mode into subsolidus convection. This causes Venus to miss the window for plate tectonics due to an extended heat-pipe childhood.

  10. Numerical studies of temperature effect on the extrusion fracture and swell of plastic micro-pipe

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Huang, Xingyuan; Xiong, Zhihua

    2018-03-01

    Temperature is a key factor that impacts extrusion forming quality of plastic micro-pipe. In this study, the effect of temperature on extrusion fracture and swell of plastic micro-pipe was investigated by numerical method. Under a certain of the melt’s flow volume, the extrusion pattern, extrusion swelling ratio of melt are obtained under different temperatures. Results show that the extrusion swelling ratio of plastic micro-pipe decreases with increasing of temperature. In order to study the reason of temperature effect, the physical distributions of plastic micro-pipe are gotten. Numerical results show that the viscosity, pressure, stress value of melt are all decreased with the increasing of temperature, which leads to decrease the extrusion swell and fracture phenomenon for the plastic micro-pipe.

  11. Developing a Systematic Corrosion Control Evaluation Approach in Flint

    EPA Science Inventory

    Presentation covers what the projects were that were recommended by the Flint Safe Drinking Water Task Force for corrosion control assessment for Flint, focusing on the sequential sampling project, the pipe rigs, and pipe scale analyses.

  12. Finite volume method and multigrid acceleration in modelling of rapid crack propagation in full-scale pipe test

    NASA Astrophysics Data System (ADS)

    Ivankovic, A.; Muzaferija, S.; Demirdzic, I.

    1997-07-01

    Rapid Crack Propagation (RCP) along pressurised plastic pipes is by far the most dangerous pipe failure mode. Despite the economic benefits offered by increasing pipe size and operating pressure, both strategies increase the risk and the potential consequences of RCP. It is therefore extremely important to account for RCP in establishing the safe operational conditions. Combined experimental-numerical study is the only reliable approach of addressing the problem, and extensive research is undertaken by various fracture groups (e.g. Southwest Research Institute - USA, Imperial College - UK). This paper presents numerical results from finite volume modelling of full-scale test on medium density polyethylene gas pressurised pipes. The crack speed and pressure profile are prescribed in the analysis. Both steady-state and transient RCPs are considered, and the comparison between the two shown. The steady-state results are efficiently achieved employing a full multigrid acceleration technique, where sets of progressively finer grids are used in V-cycles. Also, the effect of inelastic behaviour of polyethylene on RCP results is demonstrated.

  13. The development of a practical pipe auto-routing system in a shipbuilding CAD environment using network optimization

    NASA Astrophysics Data System (ADS)

    Kim, Shin-Hyung; Ruy, Won-Sun; Jang, Beom Seon

    2013-09-01

    An automatic pipe routing system is proposed and implemented. Generally, the pipe routing design as a part of the shipbuilding process requires a considerable number of man hours due to the complexity which comes from physical and operational constraints and the crucial influence on outfitting construction productivity. Therefore, the automation of pipe routing design operations and processes has always been one of the most important goals for improvements in shipbuilding design. The proposed system is applied to a pipe routing design in the engine room space of a commercial ship. The effectiveness of this system is verified as a reasonable form of support for pipe routing design jobs. The automatic routing result of this system can serve as a good basis model in the initial stages of pipe routing design, allowing the designer to reduce their design lead time significantly. As a result, the design productivity overall can be improved with this automatic pipe routing system

  14. Evidence of sublaminar drag naturally occurring in a curved pipe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Noorani, A.; Schlatter, P., E-mail: pschlatt@mech.kth.se

    Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Re{sub b} ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also inmore » agreement with Fukagata et al. [“On the lower bound of net driving power in controlled duct flows,” Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.« less

  15. Evidence of sublaminar drag naturally occurring in a curved pipe

    NASA Astrophysics Data System (ADS)

    Noorani, A.; Schlatter, P.

    2015-03-01

    Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Reb ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also in agreement with Fukagata et al. ["On the lower bound of net driving power in controlled duct flows," Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.

  16. Impacts of water quality on the corrosion of cast iron pipes for water distribution and proposed source water switch strategy.

    PubMed

    Hu, Jun; Dong, Huiyu; Xu, Qiang; Ling, Wencui; Qu, Jiuhui; Qiang, Zhimin

    2018-02-01

    Switch of source water may induce "red water" episodes. This study investigated the impacts of water quality on iron release, dissolved oxygen consumption (ΔDO), corrosion scale evolution and bacterial community succession in cast iron pipes used for drinking water distribution at pilot scale, and proposed a source water switch strategy accordingly. Three sets of old cast iron pipe section (named BP, SP and GP) were excavated on site and assembled in a test base, which had historically transported blended water, surface water and groundwater, respectively. Results indicate that an increasing Cl - or SO 4 2- concentration accelerated iron release, but alkalinity and calcium hardness exhibited an opposite tendency. Disinfectant shift from free chlorine to monochloramine slightly inhibited iron release, while the impact of peroxymonosulfate depended on the source water historically transported in the test pipes. The ΔDO was highly consistent with iron release in all three pipe systems. The mass ratio of magnetite to goethite in the corrosion scales of SP was higher than those of BP and GP and kept almost unchanged over the whole operation period. Siderite and calcite formation confirmed that an increasing alkalinity and hardness inhibited iron release. Iron-reducing bacteria decreased in the BP but increased in the SP and GP; meanwhile, sulfur-oxidizing, sulfate-reducing and iron oxidizing bacteria increased in all three pipe systems. To avoid the occurrence of "red water", a source water switch strategy was proposed based on the difference between local and foreign water qualities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Northwest view of steel plate "cans" in bay 7 of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Northwest view of steel plate "cans" in bay 7 of the main pipe mill building. Historian for scale. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  18. Computational domain length and Reynolds number effects on large-scale coherent motions in turbulent pipe flow

    NASA Astrophysics Data System (ADS)

    Feldmann, Daniel; Bauer, Christian; Wagner, Claus

    2018-03-01

    We present results from direct numerical simulations (DNS) of turbulent pipe flow at shear Reynolds numbers up to Reτ = 1500 using different computational domains with lengths up to ?. The objectives are to analyse the effect of the finite size of the periodic pipe domain on large flow structures in dependency of Reτ and to assess a minimum ? required for relevant turbulent scales to be captured and a minimum Reτ for very large-scale motions (VLSM) to be analysed. Analysing one-point statistics revealed that the mean velocity profile is invariant for ?. The wall-normal location at which deviations occur in shorter domains changes strongly with increasing Reτ from the near-wall region to the outer layer, where VLSM are believed to live. The root mean square velocity profiles exhibit domain length dependencies for pipes shorter than 14R and 7R depending on Reτ. For all Reτ, the higher-order statistical moments show only weak dependencies and only for the shortest domain considered here. However, the analysis of one- and two-dimensional pre-multiplied energy spectra revealed that even for larger ?, not all physically relevant scales are fully captured, even though the aforementioned statistics are in good agreement with the literature. We found ? to be sufficiently large to capture VLSM-relevant turbulent scales in the considered range of Reτ based on our definition of an integral energy threshold of 10%. The requirement to capture at least 1/10 of the global maximum energy level is justified by a 14% increase of the streamwise turbulence intensity in the outer region between Reτ = 720 and 1500, which can be related to VLSM-relevant length scales. Based on this scaling anomaly, we found Reτ⪆1500 to be a necessary minimum requirement to investigate VLSM-related effects in pipe flow, even though the streamwise energy spectra does not yet indicate sufficient scale separation between the most energetic and the very long motions.

  19. The change of the inlet geometry of a centrifugal compressor stage and its influence on the compressor performance

    NASA Astrophysics Data System (ADS)

    Wang, Leilei; Yang, Ce; Zhao, Ben; Lao, Dazhong; Ma, Chaochen; Li, Du

    2013-06-01

    The impact on the compressor performance is important for designing the inlet pipe of the centrifugal compressor of a vehicle turbocharger with different inlet pipes. First, an experiment was performed to determine the compressor performance from three cases: a straight inlet pipe, a long bent inlet pipe and a short bent inlet pipe. Next, dynamic sensors were installed in key positions to collect the sign of the unsteady pressure of the centrifugal compressor. Combined with the results of numerical simulations, the total pressure distortion in the pipes, the pressure distributions on the blades and the pressure variability in the diffuser are studied in detail. The results can be summarized as follows: a bent pipe results in an inlet distortion to the compressor, which leads to performance degradation, and the effect is more apparent as the mass flow rate increases. The distortion induced by the bent inlet is not only influenced by the distance between the outlet of the bent section and the leading edge of the impeller but also by the impeller rotation. The flow fields in the centrifugal impeller and the diffuser are influenced by a coupling effect produced by the upstream inlet distortion and the downstream blocking effect from the volute tongue. If the inlet geometry is changed, the distributions and the fluctuation intensities of the static pressure on the main blade surface of the centrifugal impeller and in the diffuser are changed accordingly.

  20. Recent reflux receiver developments under the US DOE program

    NASA Astrophysics Data System (ADS)

    Andraka, C. E.; Diver, R. B.; Moreno, J. B.; Moss, T. A.; Adkins, D. R.

    The United States Department of Energy (DOE) Solar Thermal Program, through Sandia National Laboratories (SNL), is cooperating with industry to commercialize dish-Stirling technology. Sandia and the DOE have actively encouraged the use of liquid metal reflux receivers in these systems to improve efficiency and lower the levelized cost of electricity. The reflux receiver uses two-phase heat transfer as a 'thermal transformer' to transfer heat from a parabolic tracking-concentrator to the heater heads of the Stirling engine. The two-phase system leads to a higher available input temperature, lower thermal stresses, longer life, and independent design of the absorber and engine sections. Two embodiments of reflux receivers have been investigated: Pool boilers and heat pipes. Several pool-boiler reflux receivers have been successfully demonstrated on sun at up to 64 kWt throughput at SNL. In addition, a bench-scale device was operated for 7500 hours to investigate materials compatibility and boiling stability. Significant progress has also been made on heat pipe receiver technology. Sintered metal wick heat pipes have been investigated extensively for application to 7.5 kWe and 25 kWe systems. One test article has amassed over 1800 hours of on-sun operation. Another was limit tested at Sandia to 65 kWt throughput. These devices incorporate a nickel-powder thick wick structure with condensate return directly to the wick surface. Circumferential tubular arteries are optionally employed to improve the operating margin. In addition, DOE has begun a development program for advanced wick structures capable of supporting the Utility Scale Joint Venture Program, requiring up to 100 kWt throughput. Promising technologies include a brazed stainless steel powdered metal wick and a stainless steel metal felt wick. Bench-scale testing has been encouraging, and on-sun testing is expected this fall. Prototype gas-fired hybrid solar receivers have also been demonstrated.

  1. Recent reflux receiver developments under the US DOE program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Andraka, C.E.; Diver, R.B.; Moreno, J.B.

    1994-10-01

    The United States Department of Energy (DOE) Solar Thermal Program, through Sandia National Laboratories (SNL), is cooperating with industry to commercialize dish-Stirling technology. Sandia and the DOE have actively encouraged the use of liquid metal reflux receivers in these systems to improve efficiency and lower the levelized cost of electricity. The reflux receiver uses two-phase heat transfer as a {open_quotes}thermal transformer{close_quotes} to transfer heat from a parabolic tracking-concentrator to the heater heads of the Stirling engine. The two-phase system leads to a higher available input temperature, lower thermal stresses, longer life, and independent design of the absorber and engine sections.more » Two embodiments of reflux receivers have been investigated: Pool boilers and heat pipes. Several pool-boiler reflux receivers have been successfully demonstrated on sun at up to 64 kWt throughput at SNL. In addition, a bench-scale device was operated for 7500 hours to investigate materials compatibility and boiling stability. Significant progress has also been made on heat pipe receiver technology. Sintered metal wick heat pipes have been investigated extensively for application to 7.5 kWe and 25 kWe systems. One test article has a massed over 1800 hours of on-sun operation. Another was limit tested at Sandia to 65 kWt throughput. These devices incorporate a nickel-powder thick wick structure with condensate return directly to the wick surface. Circumferential tubular arteries are optionally employed to improve the operating margin. In addition, DOE has begun a development program for advanced wick structures capable of supporting the Utility Scale Joint Venture Program, requiring up to 100 kWt throughput. Promising technologies include a brazed stainless steel powdered metal wick and a stainless steel metal felt wick. Bench-scale testing has been encouraging, and on-sun testing is expected this fall. Prototype gas-fired hybrid solar receivers have also been.« less

  2. Internal Corrosion Direct Assessment Detection of Water (WP #205)

    DOT National Transportation Integrated Search

    2010-12-12

    Internal corrosion of natural gas pipelines is the result of interaction between the inside pipe wall and impurities in the product being transported. Such interactions can lead to an overall loss of material thereby thinning the pipe wall and thus r...

  3. ARE WE MONITORING IN THE RIGHT PLACES FOR METALS AND RADIONUCLIDES

    EPA Science Inventory

    Recent studies of pipe deposits from metal, cement and plastic pipes have found that many regulated drinking water constituents are not conservative in the distribution system. Examples are arsenic, aluminum, radium, lead, tin, radon, copper, and manganese. Distribution system ...

  4. 53. EQUIPMENT HOUSE AND PIPING, PLANS AND ELEVATION, Y&D No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    53. EQUIPMENT HOUSE AND PIPING, PLANS AND ELEVATION, Y&D No. 107731 Scale 1/2' = 1', July 2, 1929 - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  5. Benzene, benzo(a)pyrene, and lead in smoke from tobacco products other than cigarettes.

    PubMed Central

    Appel, B R; Guirguis, G; Kim, I S; Garbin, O; Fracchia, M; Flessel, C P; Kizer, K W; Book, S A; Warriner, T E

    1990-01-01

    Benzene, benzo(a)pyrene (BaP), and lead in mainstream smoke from cigars, roll-your-own (RYO) cigarette and pipe tobaccos were sampled to evaluate their potential health significance. Results with reference cigarettes were consistent with published values, providing support for the methodology employed. The emissions of benzene and BaP, expressed as mass emitted per gram of tobacco consumed, were similar for all products evaluated; for benzene, the mean values for cigars, RYO cigarette and pipe tobaccos were 156 +/- 52, 68 +/- 11, and 242 +/- 126 micrograms/g, respectively. Mean values for BaP were 42 +/- 7 and 48 +/- 4 ng/g for cigars and RYO cigarette tobacco, respectively. Lead values were below the limit of reliable quantitation in all cases. The mean benzene concentrations in a puff ranged from 1 to 2 x 10(5) micrograms/m3 for cigars, RYO cigarette and pipe tobaccos. For BaP, the puff concentration averaged about 60 micrograms/m3 for cigars and RYO cigarette tobacco. The results suggest that smoking cigars, pipes or RYO cigarettes leads to potential exposures which exceed the No Significant Risk levels of benzene and BaP set pursuant to California's Proposition 65. These tobacco products are now required to bear a health hazard warning when sold in California. We recommend that this be adopted as national policy. PMID:2327532

  6. Drag reduction of turbulent pipe flows by circular-wall oscillation

    NASA Astrophysics Data System (ADS)

    Choi, Kwing-So; Graham, Mark

    1998-01-01

    An experimental study on turbulent pipe flows was conducted with a view to reduce their friction drag by oscillating a section of the pipe in a circumferential direction. The results indicated that the friction factor of the pipe is reduced by as much as 25% as a result of active manipulation of near-wall turbulence structure by circular-wall oscillation. An increase in the bulk velocity was clearly shown when the pipe was oscillated at a constant head, supporting the measured drag reduction in the present experiment. The percentage reduction in pipe friction was found to be better scaled with the nondimensional velocity of the oscillating wall than with its nondimensional period, confirming a suggestion that the drag reduction seem to be resulted from the realignment of longitudinal vortices into a circumferential direction by the wall oscillation.

  7. The use of MCNP and gamma spectrometry in supporting the evaluation of NORM in Libyan oil pipeline scale

    NASA Astrophysics Data System (ADS)

    Habib, Ahmed S.; Bradley, D. A.; Regan, P. H.; Shutt, A. L.

    2010-07-01

    The accumulation of scales in production pipes is a common problem in the oil industry, reducing fluid flow and also leading to costly remedies and disposal issues. Typical materials found in such scale are sulphates and carbonates of calcium and barium, or iron sulphide. Radium arising from the uranium/thorium present in oil-bearing rock formations may replace the barium or calcium in these salts to form radium salts. This creates what is known as technologically enhanced naturally occurring radioactive material (TENORM or simply NORM). NORM is a serious environmental and health and safety issue arising from commercial oil and gas extraction operations. Whilst a good deal has been published on the characterisation and measurement of radioactive scales from offshore oil production, little information has been published regarding NORM associated with land-based facilities such as that of the Libyan oil industry. The ongoing investigation described in this paper concerns an assessment of NORM from a number of land based Libyan oil fields. A total of 27 pipe scale samples were collected from eight oil fields, from different locations in Libya. The dose rates, measured using a handheld survey meter positioned on sample surfaces, ranged from 0.1-27.3 μSv h -1. In the initial evaluations of the sample activity, use is being made of a portable HPGe based spectrometry system. To comply with the prevailing safety regulations of the University of Surrey, the samples are being counted in their original form, creating a need for correction of non-homogeneous sample geometries. To derive a detection efficiency based on the actual sample geometries, a technique has been developed using a Monte Carlo particle transport code (MCNPX). A preliminary activity determination has been performed using an HPGe portable detector system.

  8. Geothermal mineralized scales in the pipe system of the geothermal Piancastagnaio power plant (Mt. Amiata geothermal area): a key to understand the stibnite, cinnabarite and gold mineralization of Tuscany (central Italy)

    NASA Astrophysics Data System (ADS)

    Morteani, Giulio; Ruggieri, Giovanni; Möller, Peter; Preinfalk, Christine

    2011-02-01

    The CO2-rich geothermal fluids produced in the Piancastagnaio geothermal field (Mt. Amiata geothermal area, Southern Tuscany, Italy) show temperatures up to 360°C and pressures of about 200 bar at depths of around 3,500 m (Giolito, Ph.D. thesis, Università degli Studi di Firenze, Italy, pp 1-147, 2005). CaCO3- and/or SiO2-dominated scales are deposited in the pipes leading to the pressure and atmospheric separators of the geothermal wells. High content of metastibnite and/or stibnite in both calcite and silica scales and Sb contents of up to 50 mg/L in the fluids indicate their mineralising potential. The red or black colours of the scales depend on the predominance of red metastibnite or black stibnite, respectively. In our condensation experiments, as well as during deposition of the scales, metastibnite is the first Sb2S3 mineral to form. In a second stage, metastibnite is transformed to stibnite. During depressurization the Hg content of geothermal fluids partitions preferentially into the gas phase, whereas Sb and As remain in the liquid phase. This separation explains the often observed areal separation of Hg and Sb mineralization. The multistage deposition of Sb in the mining district of Tuscany is due to a periodic restoration of the permeability of the ore-bearing faults by microseismic events and subsequent host rock brecciation. The still ongoing microseismic events are induced by the accumulation of high-pressure CO2-rich fluids along faults followed by mechanical failure of the faults.

  9. Characterisation of the physical composition and microbial community structure of biofilms within a model full-scale drinking water distribution system.

    PubMed

    Fish, Katherine E; Collins, Richard; Green, Nicola H; Sharpe, Rebecca L; Douterelo, Isabel; Osborn, A Mark; Boxall, Joby B

    2015-01-01

    Within drinking water distribution systems (DWDS), microorganisms form multi-species biofilms on internal pipe surfaces. A matrix of extracellular polymeric substances (EPS) is produced by the attached community and provides structure and stability for the biofilm. If the EPS adhesive strength deteriorates or is overcome by external shear forces, biofilm is mobilised into the water potentially leading to degradation of water quality. However, little is known about the EPS within DWDS biofilms or how this is influenced by community composition or environmental parameters, because of the complications in obtaining biofilm samples and the difficulties in analysing EPS. Additionally, although biofilms may contain various microbial groups, research commonly focuses solely upon bacteria. This research applies an EPS analysis method based upon fluorescent confocal laser scanning microscopy (CLSM) in combination with digital image analysis (DIA), to concurrently characterize cells and EPS (carbohydrates and proteins) within drinking water biofilms from a full-scale DWDS experimental pipe loop facility with representative hydraulic conditions. Application of the EPS analysis method, alongside DNA fingerprinting of bacterial, archaeal and fungal communities, was demonstrated for biofilms sampled from different positions around the pipeline, after 28 days growth within the DWDS experimental facility. The volume of EPS was 4.9 times greater than that of the cells within biofilms, with carbohydrates present as the dominant component. Additionally, the greatest proportion of EPS was located above that of the cells. Fungi and archaea were established as important components of the biofilm community, although bacteria were more diverse. Moreover, biofilms from different positions were similar with respect to community structure and the quantity, composition and three-dimensional distribution of cells and EPS, indicating that active colonisation of the pipe wall is an important driver in material accumulation within the DWDS.

  10. Characterisation of the Physical Composition and Microbial Community Structure of Biofilms within a Model Full-Scale Drinking Water Distribution System

    PubMed Central

    Fish, Katherine E.; Collins, Richard; Green, Nicola H.; Sharpe, Rebecca L.; Douterelo, Isabel; Osborn, A. Mark; Boxall, Joby B.

    2015-01-01

    Within drinking water distribution systems (DWDS), microorganisms form multi-species biofilms on internal pipe surfaces. A matrix of extracellular polymeric substances (EPS) is produced by the attached community and provides structure and stability for the biofilm. If the EPS adhesive strength deteriorates or is overcome by external shear forces, biofilm is mobilised into the water potentially leading to degradation of water quality. However, little is known about the EPS within DWDS biofilms or how this is influenced by community composition or environmental parameters, because of the complications in obtaining biofilm samples and the difficulties in analysing EPS. Additionally, although biofilms may contain various microbial groups, research commonly focuses solely upon bacteria. This research applies an EPS analysis method based upon fluorescent confocal laser scanning microscopy (CLSM) in combination with digital image analysis (DIA), to concurrently characterize cells and EPS (carbohydrates and proteins) within drinking water biofilms from a full-scale DWDS experimental pipe loop facility with representative hydraulic conditions. Application of the EPS analysis method, alongside DNA fingerprinting of bacterial, archaeal and fungal communities, was demonstrated for biofilms sampled from different positions around the pipeline, after 28 days growth within the DWDS experimental facility. The volume of EPS was 4.9 times greater than that of the cells within biofilms, with carbohydrates present as the dominant component. Additionally, the greatest proportion of EPS was located above that of the cells. Fungi and archaea were established as important components of the biofilm community, although bacteria were more diverse. Moreover, biofilms from different positions were similar with respect to community structure and the quantity, composition and three-dimensional distribution of cells and EPS, indicating that active colonisation of the pipe wall is an important driver in material accumulation within the DWDS. PMID:25706303

  11. KENTUCKY STRAIGHT PIPES REPORT, DECEMBER 2002

    EPA Science Inventory

    The poor sanitary conditions and water pollution problems EPA observed in the Kentucky counties of Harlan, Martin, Bath, and Montgomery were of the highest concern. The widespread scale of both the straight pipe issues as well as package plant wastewater problems present an envir...

  12. The flows structure in unsteady gas flow in pipes with different cross-sections

    NASA Astrophysics Data System (ADS)

    Plotnikov, Leonid; Nevolin, Alexandr; Nikolaev, Dmitrij

    2017-10-01

    The results of numerical simulation and experimental study of the structure of unsteady flows in pipes with different cross sections are presented in the article. It is shown that the unsteady gas flow in a circular pipe is axisymmetric without secondary currents. Steady vortex structures (secondary flows) are observed in pipes with cross sections in the form of a square and an equilateral triangle. It was found that these secondary flows have a significant impact on gas flows in pipes of complex configuration. On the basis of experimental researches it is established that the strong oscillatory phenomena exist in the inlet pipe of the piston engine arising after the closing of the intake valve. The placement of the profiled plots (with a cross section of a square or an equilateral triangle) in the intake pipe leads to the damping of the oscillatory phenomena and a more rapid stabilization of pulsating flow. This is due to the stabilizing effect of the vortex structures formed in the corners of this configuration.

  13. Characterization and release profile of (Mn, Al)-bearing deposits in drinking water distribution systems.

    PubMed

    Li, Guiwei; Ding, Yuanxun; Xu, Hongfu; Jin, Junwei; Shi, Baoyou

    2018-04-01

    Inorganic contaminants accumulation in drinking water distribution systems (DWDS) is a great threat to water quality and safety. This work assessed the main risk factors for different water pipes and discovered the release profile of accumulated materials in a full scale distribution system frequently suffered from water discoloration problem. Physicochemical characterization of pipe deposits were performed using X-ray fluorescence, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The metal release profile was obtained through continuous monitoring of a full-scale DWDS area. The results showed that aluminum and manganese were the main metals of deposits in nonmetallic pipes, while iron was dominant in iron-based pipe corrosion scales. Manganese primarily existed as MnO 2 without well crystalline form. The relative abundance of Mn and Fe in deposits changed with their distance from the water treatment plant. Compared with iron in corrosion scales, Mn and Al were more labile to be released back into bulk water during unidirectional flushing process. A main finding of this work is the co-release behavior of Mn and Al in particulate form and significant correlation exists between these two metals. Dual control of manganese and aluminum in treated water is proposed to be essential to cope with discoloration and trace metal contamination in DWDS. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. A thin gold coated hydrogen heat pipe-cryogenic target for external experiments at COSY

    NASA Astrophysics Data System (ADS)

    Abdel-Bary, M.; Abdel-Samad, S.; Elawadi, G. A.; Kilian, K.; Ritman, J.

    2009-05-01

    A gravity assisted Gold coated heat pipe (GCHP) with 5-mm diameter has been developed and tested to cool a liquid hydrogen target for external beam experiments at COSY. The need for a narrow target diameter leads us to study the effect of reducing the heat pipe diameter to 5 mm instead of 7 mm, to study the effect of coating the external surface of the heat pipe by a shiny gold layer (to decrease the radiation heat load), and to study the effect of using the heat pipe without using 20 layers of' super-insulation around it (aluminized Mylar foil) to keep the target diameter as small as possible. The developed gold coated heat pipe was tested with 20 layers of super-insulation (WI) and without super-insulation (WOI). The operating characteristics for both conditions were compared to show the advantages and disadvantages.

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Y.J.; Sohn, G.H.; Kim, Y.J.

    Typical LBB (Leak-Before-Break) analysis is performed for the highest stress location for each different type of material in the high energy pipe line. In most cases, the highest stress occurs at the nozzle and pipe interface location at the terminal end. The standard finite element analysis approach to calculate J-Integral values at the crack tip utilizes symmetry conditions when modeling near the nozzle as well as away from the nozzle region to minimize the model size and simplify the calculation of J-integral values at the crack tip. A factor of two is typically applied to the J-integral value to accountmore » for symmetric conditions. This simplified analysis can lead to conservative results especially for small diameter pipes where the asymmetry of the nozzle-pipe interface is ignored. The stiffness of the residual piping system and non-symmetries of geometry along with different material for the nozzle, safe end and pipe are usually omitted in current LBB methodology. In this paper, the effects of non-symmetries due to geometry and material at the pipe-nozzle interface are presented. Various LBB analyses are performed for a small diameter piping system to evaluate the effect a nozzle has on the J-integral calculation, crack opening area and crack stability. In addition, material differences between the nozzle and pipe are evaluated. Comparison is made between a pipe model and a nozzle-pipe interface model, and a LBB PED (Piping Evaluation Diagram) curve is developed to summarize the results for use by piping designers.« less

  16. An asymptotic analysis of the laminar-turbulent transition of yield stress fluids in pipes

    NASA Astrophysics Data System (ADS)

    Myers, Tim G.; Mitchell, Sarah L.; Slatter, Paul

    2017-02-01

    The work in this paper concerns the axisymmetric pipe flow of a Herschel-Bulkley fluid, with the aim of determining a relation between the critical velocity (defining the transition between laminar and turbulent flow) and the pipe diameter in terms of the Reynolds number Re 3. The asymptotic behaviour for large and small pipes is examined and simple expressions for the leading order terms are presented. Results are then compared with experimental data. A nonlinear regression analysis shows that for the tested fluids the transition occurs at similar values to the Newtonian case, namely in the range 2100 < Re 3 < 2500.

  17. Lead as a legendary pollutant with emerging concern: Survey of lead in tap water in an old campus building using four sampling methods.

    PubMed

    Ng, Ding-Quan; Liu, Shu-Wei; Lin, Yi-Pin

    2018-09-15

    In this study, a sampling campaign with a total of nine sampling events investigating lead in drinking water was conducted at 7 sampling locations in an old building with lead pipes in service in part of the building on the National Taiwan University campus. This study aims to assess the effectiveness of four different sampling methods, namely first draw sampling, sequential sampling, random daytime sampling and flush sampling, in lead contamination detection. In 3 out of the 7 sampling locations without lead pipe, lead could not be detected (<1.1 μg/L) in most samples regardless of the sampling methods. On the other hand, in the 4 sampling locations where lead pipes still existed, total lead concentrations >10 μg/L were consistently observed in 3 locations using any of the four sampling methods while the remaining location was identified to be contaminated using sequential sampling. High lead levels were consistently measured by the four sampling methods in the 3 locations in which particulate lead was either predominant or comparable to soluble lead. Compared to first draw and random daytime samplings, although flush sampling had a high tendency to reduce total lead in samples in lead-contaminated sites, the extent of lead reduction was location-dependent and not dependent on flush durations between 5 and 10 min. Overall, first draw sampling and random daytime sampling were reliable and effective in determining lead contamination in this study. Flush sampling could reveal the contamination if the extent is severe but tends to underestimate lead exposure risk. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Experimental Investigation of Concrete Runway Snow Melting Utilizing Heat Pipe Technology

    PubMed Central

    Su, Xin; Ye, Qing; Fu, Jianfeng

    2018-01-01

    A full scale snow melting system with heat pipe technology is built in this work, which avoids the negative effects on concrete structure and environment caused by traditional deicing chemicals. The snow melting, ice-freezing performance and temperature distribution characteristics of heat pipe concrete runway were discussed by the outdoor experiments. The results show that the temperature of the concrete pavement is greatly improved with the heat pipe system. The environment temperature and embedded depth of heat pipe play a dominant role among the decision variables of the snow melting system. Heat pipe snow melting pavement melts the snow completely and avoids freezing at any time when the environment temperature is below freezing point, which is secure enough for planes take-off and landing. Besides, the exportation and recovery of geothermal energy indicate that this system can run for a long time. This paper will be useful for the design and application of the heat pipe used in the runway snow melting. PMID:29551957

  19. Experimental Investigation of Concrete Runway Snow Melting Utilizing Heat Pipe Technology.

    PubMed

    Chen, Fengchen; Su, Xin; Ye, Qing; Fu, Jianfeng

    2018-01-01

    A full scale snow melting system with heat pipe technology is built in this work, which avoids the negative effects on concrete structure and environment caused by traditional deicing chemicals. The snow melting, ice-freezing performance and temperature distribution characteristics of heat pipe concrete runway were discussed by the outdoor experiments. The results show that the temperature of the concrete pavement is greatly improved with the heat pipe system. The environment temperature and embedded depth of heat pipe play a dominant role among the decision variables of the snow melting system. Heat pipe snow melting pavement melts the snow completely and avoids freezing at any time when the environment temperature is below freezing point, which is secure enough for planes take-off and landing. Besides, the exportation and recovery of geothermal energy indicate that this system can run for a long time. This paper will be useful for the design and application of the heat pipe used in the runway snow melting.

  20. Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces

    NASA Technical Reports Server (NTRS)

    Dussinger, Peter M.; Lindemuth, James E.

    1997-01-01

    The principal objective of this Phase 2 SBIR program was to develop and demonstrate a practically insoluble coating for nickel-based superalloys for Stirling engine heat pipe applications. Specific technical objectives of the program were: (1) Determine the solubility corrosion rates for Nickel 200, Inconel 718, and Udimet 72OLI in a simulated Stirling engine heat pipe environment, (2) Develop coating processes and techniques for capillary groove and screen wick structures, (3) Evaluate the durability and solubility corrosion rates for capillary groove and screen wick structures coated with an insoluble coating in cylindrical heat pipes operating under Stirling engine conditions, and (4) Design and fabricate a coated full-scale, partial segment of the current Stirling engine heat pipe for the Stirling Space Power Convertor program. The work effort successfully demonstrated a two-step nickel aluminide coating process for groove wick structures and interior wall surfaces in contact with liquid metals; demonstrated a one-step nickel aluminide coating process for nickel screen wick structures; and developed and demonstrated a two-step aluminum-to-nickel aluminide coating process for nickel screen wick structures. In addition, the full-scale, partial segment was fabricated and the interior surfaces and wick structures were coated. The heat pipe was charged with sodium, processed, and scheduled to be life tested for up to ten years as a Phase 3 effort.

  1. Seismic texture and amplitude analysis of large scale fluid escape pipes using time lapses seismic surveys: examples from the Loyal Field (Scotland, UK)

    NASA Astrophysics Data System (ADS)

    Maestrelli, Daniele; Jihad, Ali; Iacopini, David; Bond, Clare

    2016-04-01

    Fluid escape pipes are key features of primary interest for the analysis of vertical fluid flow and secondary hydrocarbon migration in sedimentary basin. Identified worldwide (Løset et al., 2009), they acquired more and more importance as they represent critical pathways for supply of methane and potential structure for leakage into the storage reservoir (Cartwright & Santamarina, 2015). Therefore, understanding their genesis, internal characteristics and seismic expression, is of great significance for the exploration industry. Here we propose a detailed characterization of the internal seismic texture of some seal bypass system (e.g fluid escape pipes) from a 4D seismic survey (released by the BP) recently acquired in the Loyal Field. The seal by pass structure are characterized by big-scale fluid escape pipes affecting the Upper Paleogene/Neogene stratigraphic succession in the Loyal Field, Scotland (UK). The Loyal field, is located on the edge of the Faroe-Shetland Channel slope, about 130 km west of Shetland (Quadrants 204/205 of the UKCS) and has been recently re-appraised and re developed by a consortium led by BP. The 3D detailed mapping analysis of the full and partial stack survey (processed using amplitude preservation workflows) shows a complex system of fluid pipe structure rooted in the pre Lista formation and developed across the paleogene and Neogene Units. Geometrical analysis show that pipes got diameter varying between 100-300 m and a length of 500 m to 2 km. Most pipes seem to terminate abruptly at discrete subsurface horizons or in diffuse termination suggesting multiple overpressured events and lateral fluid migration (through Darcy flows) across the overburden units. The internal texture analysis of the large pipes, (across both the root and main conduit zones), using near, medium and far offset stack dataset (processed through an amplitude preserved PSTM workflow) shows a tendency of up-bending of reflection (rather than pulls up artefacts) affected by large scale fracture (semblance image) and seem consistent with a suspended mud/sand mixture non-fluidized fluid flow. Near-Middle-Far offsets amplitude analysis confirms that most of the amplitude anomalies within the pipes conduit and terminus are only partly related to gas. An interpretation of the possible texture observed is proposed with a discussion of the noise and artefact induced by resolution and migration problems. Possible hypothetical formation mechanisms for those Pipes are discussed.

  2. Composite drill pipe and method for forming same

    DOEpatents

    Leslie, James C; Leslie, II, James C; Heard, James; Truong, Liem V; Josephson, Marvin

    2012-10-16

    A lightweight and durable drill pipe string capable of short radius drilling formed using a composite pipe segment formed to include tapered wall thickness ends that are each defined by opposed frustoconical surfaces conformed for self-aligning receipt and intimate bonding contact within an annular space between corresponding surfaces of a coaxially nested set of metal end pieces and a set of nonconductive sleeves. The distal peripheries of the nested end pieces and sleeves are then welded to each other and the sandwiched and bonded portions are radially pinned. The composite segment may include imbedded conductive leads and the axial end portions of the end pieces are shaped to form a threaded joint with the next pipe assembly that includes contact rings in the opposed surfaces of the pipe joint for contact together.

  3. Microbiology, chemistry and biofilm development in a pilot drinking water distribution system with copper and plastic pipes.

    PubMed

    Lehtola, Markku J; Miettinen, Ilkka T; Keinänen, Minna M; Kekki, Tomi K; Laine, Olli; Hirvonen, Arja; Vartiainen, Terttu; Martikainen, Pertti J

    2004-10-01

    We studied the changes in water quality and formation of biofilms occurring in a pilot-scale water distribution system with two generally used pipe materials: copper and plastic (polyethylene, PE). The formation of biofilms with time was analysed as the number of total bacteria, heterotrophic plate counts and the concentration of ATP in biofilms. At the end of the experiment (after 308 days), microbial community structure, viable biomass and gram-negative bacterial biomass were analysed via lipid biomarkers (phospholipid fatty acids and lipopolysaccharide 3-hydroxy fatty acids), and the numbers of virus-like particles and total bacteria were enumerated by SYBR Green I staining. The formation of biofilm was slower in copper pipes than in the PE pipes, but after 200 days there was no difference in microbial numbers between the pipe materials. Copper ion led to lower microbial numbers in water during the first 200 days, but thereafter there were no differences between the two pipe materials. The number of virus-like particles was lower in biofilms and in outlet water from the copper pipes than PE pipes. Pipe material influenced also the microbial and gram-negative bacterial community structure in biofilms and water.

  4. The Influence of Various Vibration Frequency on Barium Sulfate Scale Formation Of Vibrated Piping System In The Presence Citric Acid

    NASA Astrophysics Data System (ADS)

    Karaman, N.; Mangestiyono, W.; Muryanto, S.; Jamari, J.; Bayuseno, A. P.

    2018-01-01

    In this paper, the influence of vibrated piping system for BaSO4 scale formation was investigated. The vibration frequency and presence of citric acid were independent variables determining the kinetics, mass deposit and polymorph of the crystals. Correspondingly, induction time and mass of scale were obtained during the experiments. The crystalline scale was observed by scanning electron microscopy (SEM) and X-Ray Diffraction (XRD) to investigate the morphology and the phase mineral deposits, respectively. This effect indicated that the increase in vibration frequency promoted the increased deposition rate, while the pure barite with a plate-like morphology was produced in the experiments.

  5. 77 FR 3497 - Light-Walled Rectangular Pipe and Tube From Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-24

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-410 (Third Review)] Light-Walled... order on light-walled rectangular pipe and tube from Taiwan would be likely to lead to continuation or... views of the Commission are contained in USITC Publication 4301 (January 2012), Light-Walled Rectangular...

  6. A COMPARISON OF RESIDENTIAL COPPER PIPES CARRYING HOT AND COLD WATER

    EPA Science Inventory

    Each year, the U.S. EPA examines numerous lead, iron, and copper pipes pulled from active use in homes and drinking water distribution systems throughout the United States. The intent of the work is to better understand factors that influence the release of metals into drinking ...

  7. Canonical Nonlinear Viscous Core Solution in pipe and elliptical geometry

    NASA Astrophysics Data System (ADS)

    Ozcakir, Ozge

    2016-11-01

    In an earlier paper (Ozcakir et al. (2016)), two new nonlinear traveling wave solutions were found with collapsing structure towards the center of the pipe as Reynolds number R -> ∞ , which were called Nonlinear Viscous Core (NVC) states. Asymptotic scaling arguments suggested that the NVC state collapse rate scales as R - 1 / 4 where axial, radial and azimuthal velocity perturbations from Hagen-Poiseuille flow scale as R - 1 / 2, R - 3 / 4 and R - 3 / 4 respectively, while (1 - c) = O (R - 1 / 2) where c is the traveling wave speed. The theoretical scaling results were roughly consistent with full Navier-Stokes numerical computations in the range 105 < R <106 . In the present paper, through numerical solutions, we show that the scaled parameter free canonical differential equations derived in Ozcakir et al. (2016) indeed has solution that satisfies requisite far-field conditions. We also show that these are in good agreement with full Navier-Stokes calculations in a larger R range than previously calculated (R upto 106). Further, we extend our study to NVC states for pipes with elliptical cross-section and identify similar canonical structure in these cases. National Science Foundation NSF-DMS-1515755, EPSRC Grant EP/1037948/1.

  8. Manufacture of mold of polymeric composite water pipe reinforced charcoal

    NASA Astrophysics Data System (ADS)

    Zulfikar; Misdawati; Idris, M.; Nasution, F. K.; Harahap, U. N.; Simanjuntak, R. K.; Jufrizal; Pranoto, S.

    2018-03-01

    In general, household wastewater pipelines currently use thermoplastic pipes of Polyvinyl Chloride (PVC). This material is known to be not high heat resistant, contains hazardous chemicals (toxins), relatively inhospitable, and relatively more expensive. Therefore, researchers make innovations utilizing natural materials in the form of wood charcoal as the basic material of making the water pipe. Making this pipe requires a simple mold design that can be worked in the scale of household and intermediate industries. This research aims to produce water pipe mold with simple design, easy to do, and making time relatively short. Some considerations for molding materials are weight of mold, ease of raw material, strong, sturdy, and able to cast. Pipe molds are grouped into 4 (four) main parts, including: outer diameter pipe molding, pipe inside diameter, pipe holder, and pipe alignment control. Some materials have been tested as raw materials for outer diameter of pipes, such as wood, iron / steel, cement, and thermoset. The best results are obtained on thermoset material, where the process of disassembling is easier and the resulting mold weight is relatively lighter. For the inside diameter of the pipe is used stainless steel, because in addition to be resistant to chemical processes that occur, in this part of the mold must hold the press load due to shrinkage of raw materials of the pipe during the process of hardening (polymerization). Therefore, it needs high pressure resistant material and does not blend with the raw material of the pipe. The base of the mold is made of stainless steel material because it must be resistant to corrosion due to chemical processes. As for the adjustment of the pipe is made of ST 37 carbon steel, because its function is only as a regulator of the alignment of the pipe structure.

  9. Lead in ancient Rome's city waters.

    PubMed

    Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

    2014-05-06

    It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system.

  10. Association of dental caries with socioeconomic status in relation to different water fluoridation levels.

    PubMed

    Cho, Hyun-Jae; Lee, Heung-Soo; Paik, Dai-Il; Bae, Kwang-Hak

    2014-12-01

    The aim of this study was to assess the prevalence of dental caries in 11-year-old children, related to water fluoridation and family affluence scale (FAS), as an indicator of socioeconomic status (SES) in Korea. A total of eight areas were selected for study: four areas with fluoridated piped water (WF areas) and four areas with nonfluoridated piped water (non-WF areas). Non-WF areas had a similar economic level and population size compared with the WF areas. A total of 1446 elementary school students, 11 years of age, were included. They were examined, and questionnaires completed by their parents were analyzed. In the questionnaire, information about gender, FAS as an indicator of SES, occasions of daily cariogenic snack intake, occasions of daily cariogenic beverage intake, drinking of piped water, cooking with piped water, and usage of oral hygiene supplemental measures were surveyed. The bivariate association between the characteristics of the subjects and the number of decayed, filled, and missing permanent teeth (DMFT score) was analyzed through an independent samples t-test. The difference in the mean DMFT score between different FAS groups was analyzed by DMFT ratio, after adjusting for gender, oral health behaviors, and usage of piped water variables. The DMFT ratio was calculated from a Poisson regression model, because the DMFT score was not normally distributed. There was no significant association between FAS and the mean DMFT score in both areas, by bivariate analysis. After adjusting for each group of confounders, a significant association (95% CI: 1.032-1.513) was found between the FAS and mean DMFT scores in non-WF areas; however, no significant difference was observed in the WF areas (95% CI: 0.766-1.382). This study supported that water fluoridation could not only lead to a lower prevalence of dental caries, but also help to reduce the effect of SES inequalities on oral health. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Impact of RO-desalted water on distribution water qualities.

    PubMed

    Taylor, J; Dietz, J; Randall, A; Hong, S

    2005-01-01

    A large-scale pilot distribution study was conducted to investigate the impacts of blending different source waters on distribution water qualities, with an emphasis on metal release (i.e. corrosion). The principal source waters investigated were conventionally treated ground water (G1), surface water processed by enhanced treatment (S1), and desalted seawater by reverse osmosis membranes (RO). Due to the nature of raw water quality and associated treatment processes, G1 water had high alkalinity, while S1 and RO sources were characterized as high sulfate and high chloride waters, respectively. The blending ratio of different treated waters determined the quality of finished waters. Iron release from aged cast iron pipes increased significantly when exposed to RO and S1 waters: that is, the greater iron release was experienced with alkalinity reduced below the background of G1 water. Copper release to drinking water, however, increased with increasing alkalinity and decreasing pH. Lead release, on the other hand, increased with increasing chloride and decreasing sulfate. The effect of pH and alkalinity on lead release was not clearly observed from pilot blending study. The flat and compact corrosion scales observed for lead surface exposed to S1 water may be attributable to lead concentration less than that of RO water blends.

  12. Real-time contaminant detection and classification in a drinking water pipe using conventional water quality sensors: techniques and experimental results.

    PubMed

    Jeffrey Yang, Y; Haught, Roy C; Goodrich, James A

    2009-06-01

    Accurate detection and identification of natural or intentional contamination events in a drinking water pipe is critical to drinking water supply security and health risk management. To use conventional water quality sensors for the purpose, we have explored a real-time event adaptive detection, identification and warning (READiw) methodology and examined it using pilot-scale pipe flow experiments of 11 chemical and biological contaminants each at three concentration levels. The tested contaminants include pesticide and herbicides (aldicarb, glyphosate and dicamba), alkaloids (nicotine and colchicine), E. coli in terrific broth, biological growth media (nutrient broth, terrific broth, tryptic soy broth), and inorganic chemical compounds (mercuric chloride and potassium ferricyanide). First, through adaptive transformation of the sensor outputs, contaminant signals were enhanced and background noise was reduced in time-series plots leading to detection and identification of all simulated contamination events. The improved sensor detection threshold was 0.1% of the background for pH and oxidation-reduction potential (ORP), 0.9% for free chlorine, 1.6% for total chlorine, and 0.9% for chloride. Second, the relative changes calculated from adaptively transformed residual chlorine measurements were quantitatively related to contaminant-chlorine reactivity in drinking water. We have shown that based on these kinetic and chemical differences, the tested contaminants were distinguishable in forensic discrimination diagrams made of adaptively transformed sensor measurements.

  13. KNOWING CHEMISTRY CAN HELP GET THE LEAD OUT

    EPA Science Inventory

    Lead in tap water comes from the materials used in plumbing such as from leaded solder, lead pipe, and lead-containing brass found in fittings and faucets. Fortunately, the surface of brass eventually becomes passivated when in contact with most waters. Oxidants in water (usually...

  14. Second-Order Chlorine Decay and Trihalomethanes Formation in a Pilot-Scale Water Distribution Systems

    EPA Science Inventory

    It is well known that model-building of chlorine decay in real water distribution systems is difficult because chlorine decay is influenced by many factors (e.g., bulk water demand, pipe-wall demand, piping material, flow velocity, and residence time). In this paper, experiments ...

  15. 40 CFR 141.86 - Monitoring requirements for lead and copper in tap water.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... procedures specified in this paragraph. To avoid problems of residents handling nitric acid, acidification of... no plastic pipes which contain lead plasticizers, or plastic service lines which contain lead...

  16. 40 CFR 141.86 - Monitoring requirements for lead and copper in tap water.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... procedures specified in this paragraph. To avoid problems of residents handling nitric acid, acidification of... no plastic pipes which contain lead plasticizers, or plastic service lines which contain lead...

  17. Recent evaluations of crack-opening-area in circumferentially cracked pipes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rahman, S.; Brust, F.; Ghadiali, N.

    1997-04-01

    Leak-before-break (LBB) analyses for circumferentially cracked pipes are currently being conducted in the nuclear industry to justify elimination of pipe whip restraints and jet shields which are present because of the expected dynamic effects from pipe rupture. The application of the LBB methodology frequently requires calculation of leak rates. The leak rates depend on the crack-opening area of the through-wall crack in the pipe. In addition to LBB analyses which assume a hypothetical flaw size, there is also interest in the integrity of actual leaking cracks corresponding to current leakage detection requirements in NRC Regulatory Guide 1.45, or for assessingmore » temporary repair of Class 2 and 3 pipes that have leaks as are being evaluated in ASME Section XI. The objectives of this study were to review, evaluate, and refine current predictive models for performing crack-opening-area analyses of circumferentially cracked pipes. The results from twenty-five full-scale pipe fracture experiments, conducted in the Degraded Piping Program, the International Piping Integrity Research Group Program, and the Short Cracks in Piping and Piping Welds Program, were used to verify the analytical models. Standard statistical analyses were performed to assess used to verify the analytical models. Standard statistical analyses were performed to assess quantitatively the accuracy of the predictive models. The evaluation also involved finite element analyses for determining the crack-opening profile often needed to perform leak-rate calculations.« less

  18. Degradation of homogeneous polymer solutions in high shear turbulent pipe flow

    NASA Astrophysics Data System (ADS)

    Elbing, B. R.; Winkel, E. S.; Solomon, M. J.; Ceccio, S. L.

    2009-12-01

    This study quantifies degradation of polyethylene oxide (PEO) and polyacrylamide (PAM) polymer solutions in large diameter (2.72 cm) turbulent pipe flow at Reynolds numbers to 3 × 105 and shear rates greater than 105 1/s. The present results support a universal scaling law for polymer chain scission reported by Vanapalli et al. (2006) that predicts the maximum chain drag force to be proportional to Re 3/2, validating this scaling law at higher Reynolds numbers than prior studies. Use of this scaling gives estimated backbone bond strengths from PEO and PAM of 3.2 and 3.8 nN, respectively. Additionally, with the use of synthetic seawater as a solvent the onset of drag reduction occurred at higher shear rates relative to the pure water solvent solutions, but had little influence on the extent of degradation at higher shear rates. These results are significant for large diameter pipe flow applications that use polymers to reduce drag.

  19. Time Reversal Method for Pipe Inspection with Guided Wave

    NASA Astrophysics Data System (ADS)

    Deng, Fei; He, Cunfu; Wu, Bin

    2008-02-01

    The temporal-spatial focusing effect of the time reversal method on the guided wave inspection in pipes is investigated. A steel pipe model with outer diameter of 70 mm and wall thickness of 3.5 mm is numerically built to analyse the reflection coefficient of L(0,2) mode when the time reversal method is applied in the model. According to the calculated results, it is shown that a synthetic time reversal array method is effective to improve the signal-to-noise ratio of a guided wave inspection system. As an intercepting window is widened, more energy can be included in a re-emitted signal, which leads to a large reflection coefficient of L(0,2) mode. It is also shown that when a time reversed signal is reapplied in the pipe model, by analysing the motion of the time reversed wave propagating along the pipe model, a defect can be identified. Therefore, it is demonstrated that the time reversal method can be used to locate the circumferential position of a defect in a pipe. Finally, through an experiment corresponding with the pipe model, the experimental result shows that the above-mentioned method can be valid in the inspection of a pipe.

  20. 76 FR 5205 - Carbon Steel Butt-Weld Pipe Fittings from Brazil, China, Japan, Taiwan, and Thailand

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-28

    ...)] Carbon Steel Butt-Weld Pipe Fittings from Brazil, China, Japan, Taiwan, and Thailand AGENCY: United... Thailand. SUMMARY: The Commission hereby gives notice of the scheduling of expedited reviews pursuant to..., Taiwan, and Thailand would be likely to lead to continuation or recurrence of material injury within a...

  1. Internal erosion during soil pipeflow: state of science for experimental and numerical analysis

    USDA-ARS?s Scientific Manuscript database

    Many field observations have lead to speculation on the role of piping in embankment failures, landslides, and gully erosion. However, there has not been a consensus on the subsurface flow and erosion processes involved and inconsistent use of terms have exasperated the problem. One such piping proc...

  2. THE EFFECT OF PHOSPHATE ON THE MORPHOLOGICAL AND SPECTROSCOPIC PROPERTIES OF COPPER DRINKING WATER PIPES EXPERIENCING LOCALIZED CORROSION

    EPA Science Inventory

    Extensive localized or pitting corrosion of copper pipes used in household drinking-water plumbing can eventually lead to pinhole water leaks that may result in water damage, mold growth, and costly repairs. A large water system in Florida has been addressing a widespread pinhole...

  3. The Effect of Phosphate on the Morphological and Spectroscopic Properties of Copper Pipes Experiencing Localized Corrosion

    EPA Science Inventory

    Extensive localized or pitting corrosion of copper pipes used in household drinking-water plumbing can eventually lead to pinhole water leaks that may result in water damage, mold growth, and costly repairs. A growing number of problems have been associated with high pH and low ...

  4. 78 FR 64477 - Welded Large Diameter Line Pipe From Japan: Continuation of Antidumping Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ... Pipe From Japan: Continuation of Antidumping Duty Order AGENCY: Enforcement and Compliance, Formerly...) from Japan would likely lead to continuation or recurrence of dumping and material injury to an... Department published the antidumping duty order on LDLP from Japan.\\1\\ On October 1, 2012, the Department...

  5. Co-occurrence profiles of trace elements in potable water systems: a case study.

    PubMed

    Andra, Syam S; Makris, Konstantinos C; Charisiadis, Pantelis; Costa, Costas N

    2014-11-01

    Potable water samples (N = 74) from 19 zip code locations in a region of Greece were profiled for 13 trace elements composition using inductively coupled plasma mass spectrometry. The primary objective was to monitor the drinking water quality, while the primary focus was to find novel associations in trace elements occurrence that may further shed light on common links in their occurrence and fate in the pipe scales and corrosion products observed in urban drinking water distribution systems. Except for arsenic at two locations and in six samples, rest of the analyzed elements was below maximum contaminant levels, for which regulatory values are available. Further, we attempted to hierarchically cluster trace elements based on their covariances resulting in two groups; one with arsenic, antimony, zinc, cadmium, and copper and the second with the rest of the elements. The grouping trends were partially explained by elements' similar chemical activities in water, underscoring their potential for co-accumulation and co-mobilization phenomena from pipe scales into finished water. Profiling patterns of trace elements in finished water could be indicative of their load on pipe scales and corrosion products, with a corresponding risk of episodic contaminant release. Speculation was made on the role of disinfectants and disinfection byproducts in mobilizing chemically similar trace elements of human health interest from pipe scales to tap water. It is warranted that further studies may eventually prove useful to water regulators from incorporating the acquired knowledge in the drinking water safety plans.

  6. Corrosive microenvironments at lead solder surfaces arising from galvanic corrosion with copper pipe.

    PubMed

    Nguyen, Caroline K; Stone, Kendall R; Dudi, Abhijeet; Edwards, Marc A

    2010-09-15

    As stagnant water contacts copper pipe and lead solder (simulated soldered joints), a corrosion cell is formed between the metals in solder (Pb, Sn) and the copper. If the resulting galvanic current exceeds about 2 μA/cm(2), a highly corrosive microenvironment can form at the solder surface, with pH < 2.5 and chloride concentrations at least 11 times higher than bulk water levels. Waters with relatively high chloride tend to sustain high galvanic currents, preventing passivation of the solder surface, and contributing to lead contamination of potable water supplies. The total mass of lead corroded was consistent with predictions based on the galvanic current, and lead leaching to water was correlated with galvanic current. If the concentration of sulfate in the water increased relative to chloride, galvanic currents and associated lead contamination could be greatly reduced, and solder surfaces were readily passivated.

  7. Lead in ancient Rome’s city waters

    PubMed Central

    Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

    2014-01-01

    It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system. PMID:24753588

  8. Sills, aureoles and pipes in the Karoo Basin, South Africa, as triggers for Early Jurassic environmental changes

    NASA Astrophysics Data System (ADS)

    Svensen, Henrik H.; Planke, Sverre; Silkoset, Petter; Hammer, Øyvind; Iyer, Karthik; Schmid, Dani W.; Chevallier, Luc

    2017-04-01

    Most of the Large Igneous Provinces (LIPs) formed during the last 260 million years are associated with climatic change, oceanic anoxia, or extinctions in marine and terrestrial environments. Current hypotheses involve A) degassing of carbon either from oceans or shallow sea-bed reservoirs, B) carbon and sulfur degassing from flood basalts, C) degassing from sedimentary basins heavily intruded by LIPs. Here we present new data on gas generation and degassing from the Karoo LIP, based on fieldwork, borehole studies (geochemistry, petrography), and thermal modeling. Our data expand and corroborate earlier work on the sub-volcanic processes in the Karoo Basin. We show that 1) hundreds of breccia pipes are rooted in Early Jurassic sill complexes and contact aureoles within the organic-rich Ecca Group, 2) statistical analyses reveal a fractal distribution of pipes and that they are overdispersed at small scales (<50 m), but clustered at larger scales (>800 m), 3) contact aureoles show a reduction in organic matter content towards the sill contacts, reduced to zero in the nearest zones, producing more carbon gas compared to thermal model calculations, 4) we find up to 3 permil reduction in the d13C of the organic matter remaining in the aureoles, and finally 5) some pipes contain recent oil seeps. We conclude that the sill-pipe system released thermogenic gases to the Early Jurassic atmosphere and that the pipes may have acted as permanent fluid flow pathways.

  9. Transition to Turbulence in curved pipe

    NASA Astrophysics Data System (ADS)

    Hashemi, Amirreza; Loth, Francis

    2014-11-01

    Studies have shown that transitional turbulence in a curved pipe is delayed significantly compared with straight pipes. These analytical, numerical and experimental studies employed a helical geometry that is infinitely long such that the effect of the inlet and outlet can be neglected. The present study examined transition to turbulence in a finite curved pipe with a straight inlet/outlet and a 180 degrees curved pipe with a constant radius of curvature and diameter (D). We have employed the large scale direct numerical simulation (DNS) by using the spectral element method, nek5000, to simulate the flow field within curved pipe geometry with different curvature radii and Reynolds numbers to determine the point of the transition to turbulence. Long extensions for the inlet (5D) and outlet (20D) were used to diminish the effect of the boundary conditions. Our numerical results for radius of curvatures of 1.5D and 5D show transition turbulence is near Re = 3000. This is delayed compared with a straight pipe (Re = 2200) but still less that observed for helical geometries (Reynolds number less than 5000). Our research aims to describe the critical Reynolds number for transition to turbulence for a finite curved pipe at various curvature radii.

  10. Effect of sulfate on the transformation of corrosion scale composition and bacterial community in cast iron water distribution pipes

    EPA Science Inventory

    The stability of iron corrosion products and the bacterial composition of biofilm in drinking water distribution systems (DWDS) could have great impact on the water safety at the consumer ends. In this work, pipe loops were setup to investigate the transformation characteristics ...

  11. Release of accumulated arsenic from distribution pipes into tap water after arsenic treatment of source water- presentation

    EPA Science Inventory

    Toxic arsenic (As) is known to incorporate from source well water onto the scales of distribution system pipes such as iron, copper, galvanized steel and even plastic containing internal buildup of iron coatings (Lytle et al., 2010, 2004; Schock, 2015; Reiber and Dostal, 2000). W...

  12. [Effect of the change in sulphate and dissolved oxygen mass concentration on metal release in old cast iron distribution pipes].

    PubMed

    Wu, Yong-li; Shi, Bao-you; Sun, Hui-fang; Zhang, Zhi-huan; Gu, Jun-nong; Wang, Dong-sheng

    2013-09-01

    To understand the processes of corrosion by-product release and the consequent "red water" problems caused by the variation of water chemical composition in drinking water distribution system, the effect of sulphate and dissolved oxygen (DO) concentration on total iron release in corroded old iron pipe sections historically transporting groundwater was investigated in laboratory using small-scale pipe section reactors. The release behaviors of some low-level metals, such as Mn, As, Cr, Cu, Zn and Ni, in the process of iron release were also monitored. The results showed that the total iron and Mn release increased significantly with the increase of sulphate concentration, and apparent red water occurred when sulphate concentration was above 400 mg x L(-1). With the increase of sulfate concentration, the effluent concentrations of As, Cr, Cu, Zn and Ni also increased obviously, however, the effluent concentrations of these metals were lower than the influent concentrations under most circumstances, which indicated that adsorption of these metals by pipe corrosion scales occurred. Increasing DO within a certain range could significantly inhibit the iron release.

  13. Study and Control of Scour below Pipelines under unidirectional flow

    NASA Astrophysics Data System (ADS)

    Kabiri, Shima; Hoseinzadeh Dalir, Ali

    2016-04-01

    Water and other fluids pipelines laid on sandy rivers and sea bed change flow pattern around pipelines. These changes increase the bed shear stress and the degree of confusion around the pipes and cause to create scour hole below the pipes. In this situation, the occurrence of scour below the pipelines may lead to instability, fracture and bending and even breakage where cause very severe economic and environmental harms eventually. In this research as well as studying of scour under the pipelines, the bed sill had been used as a new mechanism in order to reduce and control of scour. For this purpose, 3 pipes (smooth) with different diameters (D) were modelled in flow condition of PIC U/Uc=0.8-0.9 in the channel with 11m length, 25cm width and depth of 50 cm. Experiment has been performed in below 2 modes: 1) Scour below a smooth pipe without bed sill 2) Scour below a smooth pipe with bed sill. In the 2nd modes bed sill was located at 4 different distances (L=0,D/4,D/2,D) of downstream Of the pipe central axis. In the experiments bed sill was a barrier for spreading wake vortices and it controlled erosions of downstream. Results of this research indicated that whatever the distance of bed sill from central axis of pipe is less, there is the most influence in reducing the scour depth below pipe. In the case that bed sill had been located exactly under central axis of pipe, scour depth under pipe decreased about 100% Also in this situation with passing a long time from the beginning of examination, the pipe self-burial process occurred due to vortex creation in pipe downstream and relocation of particles toward pipe.

  14. Stirling engine external heat system design with heat pipe heater

    NASA Technical Reports Server (NTRS)

    Godett, Ted M.; Ziph, Benjamin

    1986-01-01

    This final report presents the conceptual design of a liquid fueled external heating system (EHS) and the preliminary design of a heat pipe heater for the STM-4120 Stirling cycle engine, to meet the Air Force mobile electric power (MEP) requirement for units in the range of 20 to 60 kW. The EHS design had the following constraints: (1) Packaging requirements limited the overall system dimensions to about 330 mm x 250 mm x 100 mm; (2) Heat flux to the sodium heat pipe evaporator was limited to an average of 100 kW/m and a maximum of 550 kW/m based on previous experience; and (3) The heat pipe operating temperature was specified to be 800 C based on heat input requirements of the STM4-120. An analysis code was developed to optimize the EHS performance parameters and an analytical development of the sodium heat pipe heater was performed; both are presented and discussed. In addition, construction techniques were evaluated and scale model heat pipe testing performed.

  15. Reynolds-Stress and Triple-Product Models Applied to a Flow with Rotation and Curvature

    NASA Technical Reports Server (NTRS)

    Olsen, Michael E.

    2016-01-01

    Turbulence models, with increasing complexity, up to triple product terms, are applied to the flow in a rotating pipe. The rotating pipe is a challenging case for turbulence models as it contains significant rotational and curvature effects. The flow field starts with the classic fully developed pipe flow, with a stationary pipe wall. This well defined condition is then subjected to a section of pipe with a rotating wall. The rotating wall introduces a second velocity scale, and creates Reynolds shear stresses in the radial-circumferential and circumferential-axial planes. Furthermore, the wall rotation introduces a flow stabilization, and actually reduces the turbulent kinetic energy as the flow moves along the rotating wall section. It is shown in the present work that the Reynolds stress models are capable of predicting significant reduction in the turbulent kinetic energy, but triple product improves the predictions of the centerline turbulent kinetic energy, which is governed by convection, dissipation and transport terms, as the production terms vanish on the pipe axis.

  16. Failure Behavior of Elbows with Local Wall Thinning

    NASA Astrophysics Data System (ADS)

    Lee, Sung-Ho; Lee, Jeong-Keun; Park, Jai-Hak

    Wall thinning defect due to corrosion is one of major aging phenomena in carbon steel pipes in most plant industries, and it results in reducing load carrying capacity of the piping components. A failure test system was set up for real scale elbows containing various simulated wall thinning defects, and monotonic in-plane bending tests were performed under internal pressure to find out the failure behavior of them. The failure behavior of wall-thinned elbows was characterized by the circumferential angle of thinned region and the loading conditions to the piping system.

  17. 78 FR 72863 - Circular Welded Carbon Quality Steel Pipe From the People's Republic of China: Continuation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-04

    ... Quality Steel Pipe From the People's Republic of China: Continuation of Countervailing Duty Order AGENCY...) from the People's Republic of China (PRC) would likely lead to continuation or recurrence of net... reasonably foreseeable time.\\3\\ \\1\\ See Initiation of Five-Year (``Sunset'') Review, 78 FR 33063 (June 3...

  18. High Energy Vibration for Gas Piping

    NASA Astrophysics Data System (ADS)

    Lee, Gary Y. H.; Chan, K. B.; Lee, Aylwin Y. S.; Jia, ShengXiang

    2017-07-01

    In September 2016, a gas compressor in offshore Sarawak has its rotor changed out. Prior to this change-out, pipe vibration study was carried-out by the project team to evaluate any potential high energy pipe vibration problems at the compressor’s existing relief valve downstream pipes due to process condition changes after rotor change out. This paper covers high frequency acoustic excitation (HFAE) vibration also known as acoustic induced vibration (AIV) study and discusses detailed methodologies as a companion to the Energy Institute Guidelines for the avoidance of vibration induced fatigue failure, which is a common industry practice to assess and mitigate for AIV induced fatigue failure. Such detailed theoretical studies can help to minimize or totally avoid physical pipe modification, leading to reduce offshore plant shutdown days to plant shutdowns only being required to accommodate gas compressor upgrades, reducing cost without compromising process safety.

  19. Performance of a low-pressure-ratio centrifugal compressor with four diffuser designs

    NASA Technical Reports Server (NTRS)

    Klassen, H. A.

    1973-01-01

    A low-pressure-ratio centrifugal compressor was tested with four different diffuser configurations. One diffuser had airfoil vanes. Two were pipe diffusers. One pipe diffuser had 7.5 deg cone diffusing passages. The other had trumpet-shaped passages designed for linear static-pressure rise from throat to exit. The fourth configuration had flat vanes with elliptical leading edges similar to those of pipe diffusers. The side walls were contoured to produce a linear pressure rise. Peak compressor efficiencies were 0.82 with the airfoil vane and conical pipe diffusers, 0.80 with the trumpet, and 0.74 with the flat-vane design. Surge margin and useful range were greater for the airfoil-vane diffuser than for the other three.

  20. Importance of Fe and Mn Pipe Deposits to Lead and Copper Rule Compliance - abstract

    EPA Science Inventory

    When Madison, WI exceeded the lead Action Level in 1992, residential and off-line tests suggested that lead release into the water was more complex than a lead solubility mechanism. The water utility chose to address the Lead and Copper Rule (LCR) exceedance by implementing full ...

  1. Chlorine Decay and DBP formation under Different Flow Regions in PVC and Ductile Iron Pipes: Preliminary Results on the Role of flow Velocity and Radial Mass Transfer - Paper

    EPA Science Inventory

    A systematic experimental study was conducted using a pilot-scale drinking water distribution system simulator to quantify the effect of hydrodynamics, total organic carbon (TOC), initial disinfectant levels, and pipe materials on chlorine decay and disinfection by-product (DBP) ...

  2. Chlorine decay and DBP formation under different flow regions in PVC and ductile iron pipes: Preliminary results on the role of flow velocity and radial mass transfer

    EPA Science Inventory

    A systematic experimental study was conducted using a pilot-scale drinking water distribution system simulator to quantify the effect of hydrodynamics, total organic carbon (TOC), initial disinfectant levels, and pipe materials on chlorine decay and disinfection by-product (DBP) ...

  3. PECASE - Multi-Scale Experiments and Modeling in Wall Turbulence

    DTIC Science & Technology

    2014-12-23

    transition to turbulence in pipe flow have been characterized by the creation of puffs and slugs [Wygnanski and Champagne , 1973]. Puffs have been identified...Fluid Mech., 568:55–76, 2006. I. J. Wygnanski and F. H. Champagne . On transition in a pipe. Part 1: The origin of puffs and slugs and the flow in a

  4. The Scale Formation of Barite (BaSO4) from Laminar Flowing Water in The Presence of Tartaric Acid and Ba2+ Concentration Variation of Solution

    NASA Astrophysics Data System (ADS)

    Fatra, F.; Ivanto, G.; Dera, N. S.; Muryanto, S.; Bayuseno, A. P.

    2017-05-01

    The barite (BaSO4) scale is a mineral deposit that can be precipitated during the process of drilling oil and gas in the offshore. Deposite scale in pipes can cause a narrowing of the diameter of pipes, and can reduce water flowing in the pipe. The aim of this study is to investigation the effect of the tartaric acid additive and Ba2+ concentration on the growth o the scale formation of barite in the laminar flow of the piping system. Solution forming barite crystal was prepared by mixing equimolar solutions of barium chloride (BaCl2) and sodium sulfate (Na2SO4) with concentration variations of Ba2+ of 3000, 3500, 4000, 4500, and 5000 ppm. The flow rate of solution is 40 ml/min at temperature of 50 °C. Various concentrations of tartaric acid (C4H6O6) of 0 ppm, 5 ppm and 10 ppm were added to the solutions. The formation of barite from the solution was observed by ion conductivity measurement. The obtained barite crystals before and after adding tartaric acid were dried and characterized by using SEM/EDX for morphology and elemental analysis, and XRD for phase identification. The SEM results show that the morphology of the crystals are star-like particles, while XRD analysis confirmed that the barite crystals were produced during the experiments are high purity. Moreover, the tartaric acid can inhibit the crystal growth of barite.

  5. Dynamic model including piping acoustics of a centrifugal compression system

    NASA Astrophysics Data System (ADS)

    van Helvoirt, Jan; de Jager, Bram

    2007-04-01

    This paper deals with low-frequency pulsation phenomena in full-scale centrifugal compression systems associated with compressor surge. The Greitzer lumped parameter model is applied to describe the dynamic behavior of an industrial compressor test rig and experimental evidence is provided for the presence of acoustic pulsations in the compression system under study. It is argued that these acoustic phenomena are common for full-scale compression systems where pipe system dynamics have a significant influence on the overall system behavior. The main objective of this paper is to extend the basic compressor model in order to include the relevant pipe system dynamics. For this purpose a pipeline model is proposed, based on previous developments for fluid transmission lines. The connection of this model to the lumped parameter model is accomplished via the selection of appropriate boundary conditions. Validation results will be presented, showing a good agreement between simulation and measurement data. The results indicate that the damping of piping transients depends on the nominal, time-varying pressure and flow velocity. Therefore, model parameters are made dependent on the momentary pressure and a switching nonlinearity is introduced into the model to vary the acoustic damping as a function of flow velocity. These modifications have limited success and the results indicate that a more sophisticated model is required to fully describe all (nonlinear) acoustic effects. However, the very good qualitative results show that the model adequately combines compressor and pipe system dynamics. Therefore, the proposed model forms a step forward in the analysis and modeling of surge in full-scale centrifugal compression systems and opens the path for further developments in this field.

  6. Overdamped large-eddy simulations of turbulent pipe flow up to Reτ = 1500

    NASA Astrophysics Data System (ADS)

    Feldmann, Daniel; Avila, Marc

    2018-04-01

    We present results from large-eddy simulations (LES) of turbulent pipe flow in a computational domain of 42 radii in length. Wide ranges of shear the Reynolds number and Smagorinsky model parameter are covered, 180 ≤ Reτ ≤ 1500 and 0.05 ≤ Cs ≤ 1.2, respectively. The aim is to asses the effect of Cs on the resolved flow field and turbulence statistics as well as to test whether very large scale motions (VLSM) in pipe flow can be isolated from the near-wall cycle by enhancing the dissipative character of the static Smagorinsky model with elevated Cs values. We found that the optimal Cs to achieve best agreement with reference data varies with Reτ and further depends on the wall normal location and the quantity of interest. Furthermore, for increasing Reτ , the optimal Cs for pipe flow LES seems to approach the theoretically optimal value for LES of isotropic turbulence. In agreement with previous studies, we found that for increasing Cs small-scale streaks in simple flow field visualisations are gradually quenched and replaced by much larger smooth streaks. Our analysis of low-order turbulence statistics suggests, that these structures originate from an effective reduction of the Reynolds number and thus represent modified low-Reynolds number near-wall streaks rather than VLSM. We argue that overdamped LES with the static Smagorinsky model cannot be used to unambiguously determine the origin and the dynamics of VLSM in pipe flow. The approach might be salvaged by e.g. using more sophisticated LES models accounting for energy flux towards large scales or explicit anisotropic filter kernels.

  7. Oscillating-Coolant Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Scotti, Stephen J.; Blosser, Max L.; Camarda, Charles J.

    1992-01-01

    Devices useful in situations in which heat pipes inadequate. Conceptual oscillating-coolant heat exchanger (OCHEX) transports heat from its hotter portions to cooler portions. Heat transported by oscillation of single-phase fluid, called primary coolant, in coolant passages. No time-averaged flow in tubes, so either heat removed from end reservoirs on every cycle or heat removed indirectly by cooling sides of channels with another coolant. Devices include leading-edge cooling devices in hypersonic aircraft and "frost-free" heat exchangers. Also used in any situation in which heat pipe used and in other situations in which heat pipes not usable.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kornfeldt, H.; Bjoerk, K.O.; Ekstroem, P.

    The protection against dynamic effects in connection with potential pipe breaks has been implemented in different ways in the development of BWR reactor designs. First-generation plant designs reflect code requirements in effect at that time which means that no piping restraint systems were designed and built into those plants. Modern designs have, in contrast, implemented full protection against damage in connection with postulated pipe breaks, as required in current codes and regulations. Moderns standards and current regulatory demands can be met for the older plants by backfitting pipe whip restraint hardware. This could lead to several practical difficulties as thesemore » installations were not anticipated in the original plant design and layout. Meeting the new demands by analysis would in this situation have great advantages. Application of leak-before-break criteria gives an alternative opportunity of meeting modem standards in reactor safety design. Analysis takes into account data specific to BWR primary system operation, actual pipe material properties, piping loads and leak detection capability. Special attention must be given to ensure that the data used reflects actual plant conditions.« less

  9. The effects of acid precipitation runoff episodes on reservoir and tapwater quality in an Appalachian Mountain water supply.

    PubMed Central

    Sharpe, W E; DeWalle, D R

    1990-01-01

    The aluminum concentration and Ryznar Index increased and the pH decreased in a small Appalachian water supply reservoir following acid precipitation runoff episodes. Concomitant increases in tapwater aluminum and decreases in tapwater pH were also observed at two homes in the water distribution system. Lead concentrations in the tapwater of one home frequently exceeded recommended levels, although spatial and temporal variation in tapwater copper and lead concentrations was considerable. Since source water and reservoir water copper and lead concentrations were much lower, the increased copper and lead concentrations in tapwater were attributed to corrosion of household plumbing. Tapwater copper concentration correlated well with tapwater pH and tapwater temperature. Asbestos fibers were not detected in tapwater. The asbestos-cement pipe in the water distribution system was protected by a spontaneous metallic coating that inhibited fiber release from the pipe. Several simultaneous reactions were hypothesized to be taking place in the distribution system that involved corrosion of metallic components and coating of asbestos-cement pipe components in part with corrosion products and in part by cations of watershed origin. Greater water quality changes might be expected in areas of higher atmospheric deposition. Images FIGURE 5. FIGURE 6. PMID:2088742

  10. Bacterial community radial-spatial distribution in biofilms along pipe wall in chlorinated drinking water distribution system of East China.

    PubMed

    Liu, Jingqing; Ren, Hongxing; Ye, Xianbei; Wang, Wei; Liu, Yan; Lou, Liping; Cheng, Dongqing; He, Xiaofang; Zhou, Xiaoyan; Qiu, Shangde; Fu, Liusong; Hu, Baolan

    2017-01-01

    Biofilms in the pipe wall may lead to water quality deterioration and biological instability in drinking water distribution systems (DWDSs). In this study, bacterial community radial-spatial distribution in biofilms along the pipe wall in a chlorinated DWDS of East China was investigated. Three pipes of large diameter (300, 600, and 600 mm) were sampled in this DWDS, including a ductile cast iron pipe (DCIP) with pipe age of 11 years and two gray cast iron pipes (GCIP) with pipe ages of 17 and 19 years, and biofilms in the upper, middle, and lower parts of each pipe wall were collected. Real-time quantitative polymerase chain reaction (qPCR) and culture-based method were used to quantify bacteria. 454 pyrosequencing was used for bacterial community analysis. The results showed that the biofilm density and total solid (TS) and volatile solid (VS) contents increased gradually from the top to the bottom along the pipe wall. Microorganisms were concentrated in the upper and lower parts of the pipe wall, together accounting for more than 80 % of the total biomass in the biofilms. The bacterial communities in biofilms were significantly different in different areas of the pipe wall and had no strong interaction. Compared with the upper and lower parts of the pipe wall, the bacterial community in the middle of the pipe wall was distributed evenly and had the highest diversity. The 16S rRNA genes of various possible pathogens, including Escherichia coli, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Salmonella enterica, were detected in the biofilms, and the abundances of these possible pathogens were highest in the middle of the pipe wall among three areas. The detachment of the biofilms is the main reason for the deterioration of the water quality in DWDSs. The results of this study suggest that the biofilms in the middle of the pipe wall have highly potential risk for drinking water safety, which provides new ideas for the study of the microbial ecology in DWDS.

  11. Public Meeting Federal Register Notices and Presentations about Prohibitions on use of Lead Pipes, Solder and Flux

    EPA Pesticide Factsheets

    This page contains federal register notices, a presentation, and a summary of the webinar. The presentation provides a consumer perspective on the lead free requirements, including challenges faced by consumers in identifying lead free products.

  12. Altitude Performance Characteristics of Tail-pipe Burner with Variable-area Exhaust Nozzle

    NASA Technical Reports Server (NTRS)

    Jansen, Emmert T; Thorman, H Carl

    1950-01-01

    An investigation was conducted in the NACA Lewis altitude wind tunnel to determine effect of altitude and flight Mach number on performance of tail-pipe burner equipped with variable-area exhaust nozzle and installed on full-scale turbojet engine. At a given flight Mach number, with constant exhaust-gas and turbine-outlet temperatures, increasing altitude lowered the tail-pipe combustion efficiency and raised the specific fuel consumption while the augmented thrust ratio remained approximately constant. At a given altitude, increasing flight Mach number raised the combustion efficiency and augmented thrust ratio and lowered the specific fuel consumption.

  13. Experimental study of geysers through a vent pipe connected to flowing sewers.

    PubMed

    Huang, Biao; Wu, Shiqiang; Zhu, David Z; Schulz, Harry E

    2017-04-01

    Geysers of air-water mixtures in urban drainage systems is receiving considerable attention due to public safety concerns. However, the geyser formation process and its relation with air release from pressurized pipes are still relatively little known. A large-scale physical model, that consisted of a main tunnel with a diameter of 270 mm and a length of 25 m connecting two reservoirs and a vertical vent pipe, was established to investigate geyser evolution and pressure transients. Experimental results including dynamic pressure data and high speed videos were analysed in order to characterize geysering flow through the vent pipe. Pressure transients were observed during geysering events. Their amplitudes were found to be about three times the driving pressure head and their periods were close to the classic surge tank predictions. The influence of flow rate and vent pipe size were examined: geyser heights and pressure peaks decreased for small flow rate and large diameter vent pipe. It is suggested that geyser heights are related with the pressure head and the density of the air-water mixture.

  14. Liquid metal micro heat pipes for space radiator applications

    NASA Technical Reports Server (NTRS)

    Gerner, F. M.; Henderson, H. T.

    1995-01-01

    Micromachining is a chemical means of etching three-dimensional structures, typically in single-crystalline silicon. These techniques are leading toward what is coming to be referred to as MEMS (micro electro mechanical systems), where in addition to the ordinary two dimensional (planar) microelectronics, it is possible to build three-dimensional micromotors, electrically-actuated microvalves, hydraulic systems, and much more on the same microchip. These techniques become possible because of differential etching rates of various crystallographic planes and materials used for semiconductor microfabrication. The University of Cincinnati group in collaboration with NASA Lewis formed micro heat pipes in silicon by the above techniques. Work is ongoing at a modest level, but several essential bonding and packaging techniques have been recently developed. Currently, we have constructed and filled water/silicon micro heat pipes. Preliminary thermal tests of arrays of 125 micro heat pipes etched in a 1 inch x 1 inch x 250 micron silicon wafer have been completed. These pipes are instrumented with extremely small P-N junctions to measure their effective conductivity and their maximum operating power. A relatively simple one-dimensional model has been developed in order to predict micro heat pipes' operating characteristics. This information can be used to optimize micro heat pipe design with respect to length, hydraulic diameter, and number of pipes. Work is progressing on the fabrication of liquid-metal micro heat pipes. In order to be compatible with liquid metal (sodium or potassium), the inside of the micro heat pipes will be coated with a refractory metal (such as tungsten, molybdenum, or titanium).

  15. Scale inhibition in geothermal operations: experiments with Dequest 2060 phosphonate in Republic's East Mesa Field

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vetter, O.J.; Campbell, D.A.

    Two calcium carbonate (CaCO/sub 3/) scale inhibition tests have been performed at East Mesa wells number 16-29 and number 56-30. The first test at well number 16-29 could not be finished due to downhole pump problems. However, two inhibitor concentration runs were completed and a third run started before the pump failed. A follow-up test at well number 56-30 was completed according to the original plan. Typical power plant conditions (i.e., pressure and temperature drops, flow conditions) were simulated by using test loops (pipe diameters of eight inches at well number 16-29 and twelve inches at well number 56-30) andmore » field separators. Untreated East Mesa brine exhibits a calcium carbonate scale tendency as soon as the pressure is dropped below 75 psig. The uninhibited brine from well number 16-29 formed a maximum scale thickness of 0.5 inch in an eight inch ID pipe after a 92.75 hour test run at an average production rate of 375,000 lb/hr. The brine from well number 56-30 formed a maximum scale thickness of 1.25 inches in a twelve inch ID pipe after a 104 hour test run at an average production rate of 722,000 lb/hr. The principal conclusions of this test work are listed.« less

  16. CHALLENGES IN MAINTAINING DRINKING WATER QUALITY AT THE TAP: CONTAMINATION WITH TOXIC LEAD

    EPA Science Inventory

    Aging drinking water infrastructure in the US was given a grade of D (poor) by the American Society of Civil Engineers, and was voted as the most urgent of all societal infrastructure challenges. Legacy lead pipe, leaded solder and/or leaded brass are a particularly notorious old...

  17. NRL Review 1989-1990

    DTIC Science & Technology

    1990-06-01

    NancY L. Garland, James W. Fleming, and Herbert H. N¢’so, Epoxy Coatings for Shipboard Copper-Nickel Piping 113 Robert F. Brady, Jr. ELECTROMAGNETIC...carrier collection-holding-transfer Positioning System. Today, NRL is the Navy’s discharge piping systems. Laboratory researchers lead laboratory in space...several confinement fusion target heating at short years, congressionally approved military wavelengths. A new 3-MJ, 10-MA pulsed- construction

  18. The Effect of Flow Swirling on the Safety and Reliability of Nuclear Power Installations of New Generation

    NASA Astrophysics Data System (ADS)

    Mitrofanova, O. V.; Ivlev, O. A.; Urtenov, D. S.

    2018-03-01

    Hydrodynamics and heat exchange in the elements of thermal hydraulic tracts of ship nuclear reactors of the new generation were numerically simulated in this work. Parts of the coolant circuit in the collector and piping systems with geometries that may lead to generation of stable large-scale vortexes, causing a wide range of acoustic oscillations of the coolant, were selected as modeling objects. The purpose of the research is to develop principles of physical and mathematical modeling for scientific substantiation of optimal layout solutions that ensure enhanced operational life of icebreaker’s nuclear power installations of new generation with reactors of integral type.

  19. A Study of Applying Pulsed Remote Field Eddy Current in Ferromagnetic Pipes Testing

    PubMed Central

    Luo, Qingwang; Shi, Yibing; Wang, Zhigang; Zhang, Wei; Li, Yanjun

    2017-01-01

    Pulsed Remote Field Eddy Current Testing (PRFECT) attracts the attention in the testing of ferromagnetic pipes because of its continuous spectrum. This paper simulated the practical PRFECT of pipes by using ANSYS software and employed Least Squares Support Vector Regression (LSSVR) to extract the zero-crossing time to analyze the pipe thickness. As a result, a secondary peak is found in zero-crossing time when transmitter passed by a defect. The secondary peak will lead to wrong quantification and the localization of defects, especially when defects are found only at the transmitter location. Aiming to eliminate the secondary peaks, double sensing coils are set in the transition zone and Wiener deconvolution filter is applied. In the proposed method, position dependent response of the differential signals from the double sensing coils is calibrated by employing zero-mean normalization. The methods proposed in this paper are validated by analyzing the simulation signals and can improve the practicality of PRFECT of ferromagnetic pipes. PMID:28475141

  20. A Study of Applying Pulsed Remote Field Eddy Current in Ferromagnetic Pipes Testing.

    PubMed

    Luo, Qingwang; Shi, Yibing; Wang, Zhigang; Zhang, Wei; Li, Yanjun

    2017-05-05

    Pulsed Remote Field Eddy Current Testing (PRFECT) attracts the attention in the testing of ferromagnetic pipes because of its continuous spectrum. This paper simulated the practical PRFECT of pipes by using ANSYS software and employed Least Squares Support Vector Regression (LSSVR) to extract the zero-crossing time to analyze the pipe thickness. As a result, a secondary peak is found in zero-crossing time when transmitter passed by a defect. The secondary peak will lead to wrong quantification and the localization of defects, especially when defects are found only at the transmitter location. Aiming to eliminate the secondary peaks, double sensing coils are set in the transition zone and Wiener deconvolution filter is applied. In the proposed method, position dependent response of the differential signals from the double sensing coils is calibrated by employing zero-mean normalization. The methods proposed in this paper are validated by analyzing the simulation signals and can improve the practicality of PRFECT of ferromagnetic pipes.

  1. The plumbing of the global biological pump: Efficiency control through leaks, pathways, and time scales

    NASA Astrophysics Data System (ADS)

    Pasquier, Benoît; Holzer, Mark

    2016-08-01

    We systematically quantify the pathways and time scales that set the efficiency, Ebio, of the global biological pump by applying Green-function-based diagnostics to a data-assimilated phosphorus cycle embedded in a jointly assimilated ocean circulation. We consider "bio pipes" that consist of phosphorus paths that connect specified regions of last biological utilization with regions where regenerated phosphate first reemerges into the euphotic zone. The bio pipes that contribute most to Ebio connect the Eastern Equatorial Pacific (EEqP) and Equatorial Atlantic to the Southern Ocean ((21 ± 3)% of Ebio), as well as the Southern Ocean to itself ((15 ± 3)% of Ebio). The bio pipes with the largest phosphorus flow rates connect the EEqP to itself and the subantarctic Southern Ocean to itself. The global mean sequestration time of the biological pump is 130 ± 70 years, while the sequestration time of the bio pipe from anywhere to the Antarctic region of the Southern Ocean is 430 ± 30 years. The distribution of phosphorus flowing within a given bio pipe is quantified by its transit-time partitioned path density. For the largest bio pipes, ˜1/7 of their phosphorus is carried by thermocline paths with transit times less than ˜300-400 years, while ˜4/7 of their phosphorus is carried by abyssal paths with transit times exceeding ˜700 years. The path density reveals that Antarctic Intermediate Water carries about a third of the regenerated phosphate last utilized in the EEqP that is destined for the Southern Ocean euphotic zone. The Southern Ocean is where (62 ± 2)% of the regenerated inventory and (69 ± 1)% of the preformed inventory first reemerge into the euphotic zone.

  2. The cost of simplifying air travel when modeling disease spread.

    PubMed

    Lessler, Justin; Kaufman, James H; Ford, Daniel A; Douglas, Judith V

    2009-01-01

    Air travel plays a key role in the spread of many pathogens. Modeling the long distance spread of infectious disease in these cases requires an air travel model. Highly detailed air transportation models can be over determined and computationally problematic. We compared the predictions of a simplified air transport model with those of a model of all routes and assessed the impact of differences on models of infectious disease. Using U.S. ticket data from 2007, we compared a simplified "pipe" model, in which individuals flow in and out of the air transport system based on the number of arrivals and departures from a given airport, to a fully saturated model where all routes are modeled individually. We also compared the pipe model to a "gravity" model where the probability of travel is scaled by physical distance; the gravity model did not differ significantly from the pipe model. The pipe model roughly approximated actual air travel, but tended to overestimate the number of trips between small airports and underestimate travel between major east and west coast airports. For most routes, the maximum number of false (or missed) introductions of disease is small (<1 per day) but for a few routes this rate is greatly underestimated by the pipe model. If our interest is in large scale regional and national effects of disease, the simplified pipe model may be adequate. If we are interested in specific effects of interventions on particular air routes or the time for the disease to reach a particular location, a more complex point-to-point model will be more accurate. For many problems a hybrid model that independently models some frequently traveled routes may be the best choice. Regardless of the model used, the effect of simplifications and sensitivity to errors in parameter estimation should be analyzed.

  3. MTR WING, TRA604, INTERIOR. BASEMENT. INTERIOR VIEW FROM SAME LOCATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR WING, TRA-604, INTERIOR. BASEMENT. INTERIOR VIEW FROM SAME LOCATION IN WEST CORRIDOR AS PHOTO ID-33-G-42 BUT CAMERA FACES SOUTH. SIGN ON DOOR FOR "PIPE TUNNEL" WARNS OF RADIOLOGICAL AND ASBESTOS HAZARDS. DOOR HAS METAL HASPS. SIGN ON OVERHEAD WASTE HEAT RECOVERY PIPES SAYS THEY CONTAIN "ASBESTOS FREE INSULATION." FIRE DOOR AT LEFT LEADS TO STAIRWAY TO FIRST FLOOR. DOOR AT RIGHT LEADS TO ROOM WHICH ONCE CONTAINED MTR LIBRARY. INL NEGATIVE NO. HD46-13-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  4. Guidance and control of MIR TDL radiation via flexible hollow metallic rectangular pipes and fibers for possible LHS and other optical system compaction and integration

    NASA Technical Reports Server (NTRS)

    Yu, C.

    1983-01-01

    Flexible hollow metallic rectangular pipes and infrared fibers are proposed as alternate media for collection, guidance and manipulation of mid-infrared tunable diode laser (TDL) radiation. Certain features of such media are found to be useful for control of TDL far field patterns, polarization and possibly intensity fluctuations. Such improvement in dimension compatibility may eventually lead to laser heterodyne spectroscopy (LHS) and optical communication system compaction and integration. Infrared optical fiber and the compound parabolic coupling of light into a hollow pipe waveguide are discussed as well as the design of the waveguide.

  5. Correlation Between Surface Area and Dissolving Properties of Lead - A Step in the Investigation of Higher than Standard Lead Concentration in Drinking Water in Washington, D.C.

    NASA Astrophysics Data System (ADS)

    Hua, M.; Garduno, L.; Mondragon, J. D.; Cuff, K. E.

    2004-12-01

    Several recently published articles by the Washington Post exposing the alarming concentration of lead in drinking water from schools and homes in the Washington D.C. area sparked our interest in the correlation between lead-containing materials used in plumbing and rate of lead solubility. Elementary children who attend schools in various regions of the District were contacted by San Francisco Bay Area- based high school students who are participants in the NSF-sponsored Environmental Science Information Technology Activities (ESITA) project. After receiving a thorough explanation of required sampling procedures, the elementary school children sent 500 ml water samples from their homes and schools to Berkeley along with information on the locations from which the water samples were collected. These water samples were analyzed for lead content at the Environmental Science Research Program laboratory at Lawrence Hall of Science. The majority of the samples contained more than 15 ppb of lead, which is the EPA action level. We hypothesize that there are three possible sources of lead in the drinking water: 1) lead pipes in the water main; 2) lead pipes in the service main; and 3) lead soldering that was often previously used to connect piping. We chose to investigate the effect of lead-based solder on the overall lead concentration in water. Using a soldering iron, we melted lead solder to create discs ranging from one to five centimeter diameter and one to thirty-six grams of mass. These discs were then placed into a beaker with 500 ml of 7.1pH distilled water and allowed to stand for 48 hours. At the end of 48 hours, the water samples were prepared for analysis using the EPA approved lead-dithizone procedure. Results showed an exponential relationship between disc surface area and the concentration of dissolved lead measured in the sample. Therefore, lead-based solder can represent a possible major source of lead contamination.

  6. 5. INDUSTRIAL PIPING SYSTEM FOR 500 H.P. LLEWELLYN BOILER, ADDITION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. INDUSTRIAL PIPING SYSTEM FOR 500 H.P. LLEWELLYN BOILER, ADDITION TO POWER HOUSE. United Engineering Company Ltd., Alameda Shipyard. John Hudspeth, architect, foot of Main Street, Alameda, California. Sheet M1. Plan no. 10,551. Scale 1/4 inch to the foot. June 1, 1945. pencil on vellum - United Engineering Company Shipyard, Boiler House, 2900 Main Street, Alameda, Alameda County, CA

  7. OCCURRENCE AND SIGNIFICANCE OF TETRAVALENT LEAD IN NEW ENGLAND

    EPA Science Inventory

    USEPA analyses of lead service line specimens throughout the United States have found evidence of substantial tetravalent lead (Pb+4 in the form of PbO2 solids) in one or more samples from over 25% of systems who have submitted pipe samples. The most “newsworthy” instance of the ...

  8. Thermal Transients in District Heating Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chertkov, Michael; Novitsky, Nikolai N.

    Heat fluxes in a district heating pipeline systems need to be controlled on the scale from minutes to an hour to adjust to evolving demand. There are two principal ways to control the heat flux - keep temperature fixed but adjust velocity of the carrier (typically water) or keep the velocity flow steady but then adjust temperature at the heat producing source (heat plant). Here, we study the latter scenario, commonly used for operations in Russia and Nordic countries, and analyze dynamics of the heat front as it propagates through the system. Steady velocity flows in the district heating pipelinesmore » are typically turbulent and incompressible. Changes in the heat, on either consumption or production sides, lead to slow transients which last from tens of minutes to hours. We classify relevant physical phenomena in a single pipe, e.g. turbulent spread of the turbulent front. We then explain how to describe dynamics of temperature and heat flux evolution over a network efficiently and illustrate the network solution on a simple example involving one producer and one consumer of heat connected by “hot” and “cold” pipes. We conclude the manuscript motivating future research directions.« less

  9. Thermal Transients in District Heating Systems

    DOE PAGES

    Chertkov, Michael; Novitsky, Nikolai N.

    2018-01-18

    Heat fluxes in a district heating pipeline systems need to be controlled on the scale from minutes to an hour to adjust to evolving demand. There are two principal ways to control the heat flux - keep temperature fixed but adjust velocity of the carrier (typically water) or keep the velocity flow steady but then adjust temperature at the heat producing source (heat plant). Here, we study the latter scenario, commonly used for operations in Russia and Nordic countries, and analyze dynamics of the heat front as it propagates through the system. Steady velocity flows in the district heating pipelinesmore » are typically turbulent and incompressible. Changes in the heat, on either consumption or production sides, lead to slow transients which last from tens of minutes to hours. We classify relevant physical phenomena in a single pipe, e.g. turbulent spread of the turbulent front. We then explain how to describe dynamics of temperature and heat flux evolution over a network efficiently and illustrate the network solution on a simple example involving one producer and one consumer of heat connected by “hot” and “cold” pipes. We conclude the manuscript motivating future research directions.« less

  10. Peak Lead Levels and Diagnostics in Lead Service Lines Dominated by PbO2 - abstract

    EPA Science Inventory

    Multiple studies have presented “profiles” of water lead levels from tap to main through lead service lines (LSLs), in systems where the LSLs were coated with common Pb(II) corrosion solids. These Pb(II) solids were either actual Pb(II) minerals or Pb(II) sorbed onto other pipe ...

  11. Mineralogical and Molecular Microbial Characterization of a Lead Pipe Removed from a Drinking Water Distribution System

    EPA Science Inventory

    The U.S. Environmental Protection Agency's (US EPA) Lead and Copper Rule established an action level for lead of 0.0 15 mg/L in a 1 liter first draw sample at the consumer's tap. Lead corrosion and solubility in drinking water distribution systems are largely controlled by the fo...

  12. Reynolds-number dependence of the longitudinal dispersion in turbulent pipe flow.

    PubMed

    Hawkins, Christopher; Angheluta, Luiza; Krotkiewski, Marcin; Jamtveit, Bjørn

    2016-04-01

    In Taylor's theory, the longitudinal dispersion in turbulent pipe flows approaches, on long time scales, a diffusive behavior with a constant diffusivity K_{L}, which depends empirically on the Reynolds number Re. We show that the dependence on Re can be determined from the turbulent energy spectrum. By using the intimate connection between the friction factor and the longitudinal dispersion in wall-bounded turbulence, we predict different asymptotic scaling laws of K_{L}(Re) depending on the different turbulent cascades in two-dimensional turbulence. We also explore numerically the K_{L}(Re) dependence in turbulent channel flows with smooth and rough walls using a lattice Boltzmann method.

  13. Experience with flexible pipe in sour service environment: A case study (the Arabian Gulf)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Maslamani, M.J.

    The suitability of a flexible pipe was evaluated on a trial basis for a lift gas line in a sour oil field in the State of Qatar, in the Arabian Gulf. Flexible pipes have been successfully used in the oil and gas industries for transportation of methanol, benzene and gas condensates in wet sweet environment at temperatures of up to 80 C. However, there is little or no information available as to its corrosion resistance in sour service wells containing 6% CO{sub 2} with 3% mole H{sub 2}S and at moderate temperatures. The present experience with a flexible pipe inmore » the gas field of Qatar has shown that under sour service conditions, the layered, composite material can suffer severe degradation leading to failure. A detailed inspection and failure analysis of the flexible pipe forms the basis of this paper. The failure demonstrates the significant effects of stress level, environmental aggressiveness, and localized hard zones in promoting Sulfide Stress Cracking (SSC). Permeability of this sour gas through the composite layer of the flexible pipe resulted in varying degree of sulfide attack and hydrogen embrittlement depending on the susceptibility of the multi layered material.« less

  14. Statespace geometry of puff formation in pipe flow

    NASA Astrophysics Data System (ADS)

    Budanur, Nazmi Burak; Hof, Bjoern

    2017-11-01

    Localized patches of chaotically moving fluid known as puffs play a central role in the transition to turbulence in pipe flow. Puffs coexist with the laminar flow and their large-scale dynamics sets the critical Reynolds number: When the rate of puff splitting exceeds that of decaying, turbulence in a long pipe becomes sustained in a statistical sense. Since puffs appear despite the linear stability of the Hagen-Poiseuille flow, one expects them to emerge from the bifurcations of finite-amplitude solutions of Navier-Stokes equations. In numerical simulations of pipe flow, Avila et al., discovered a pair of streamwise localized relative periodic orbits, which are time-periodic solutions with spatial drifts. We combine symmetry reduction and Poincaré section methods to compute the unstable manifolds of these orbits, revealing statespace structures associated with different stages of puff formation.

  15. Main Design Principles of the Cold Beam Pipe in the FastRamped Superconducting Accelerator Magnets for Heavy Ion Synchrotron SIS100

    NASA Astrophysics Data System (ADS)

    Mierau, A.; Schnizer, P.; Fischer, E.; Macavei, J.; Wilfert, S.; Koch, S.; Weiland, T.; Kurnishov, R.; Shcherbakov, P.

    SIS100, the world second large scale heavy ion synchrotron using fast ramped superconducting magnets, is to be built at FAIR. Its high current operation of intermediate charge state ions requires stable vacuum pressures < 10-12 mbar under dynamic machine conditions which are only achievable when the whole beam pipe is used as an huge cryopump. In order to find technological feasible design solutions, three opposite requirements have to be met: minimum magnetic field distortion caused by AC losses, mechanical stability and low and stable wall temperatures of the beam pipe. We present the possible design versions of the beam pipe for the high current curved dipole. The pros and cons of these proposed designs were studied using simplified analytical models, FEM calculations and tests on models.

  16. Estimating the leakage contribution of phosphate dosed drinking water to environmental phosphorus pollution at the national-scale.

    PubMed

    Ascott, M J; Gooddy, D C; Lapworth, D J; Stuart, M E

    2016-12-01

    Understanding sources of phosphorus (P) to the environment is critical for the management of freshwater and marine ecosystems. Phosphate is added at water treatment works for a variety of reasons: to reduce pipe corrosion, to lower dissolved lead and copper concentrations at customer's taps and to reduce the formation of iron and manganese precipitates which can lead to deterioration in the aesthetic quality of water. However, the spatial distribution of leakage into the environment of phosphate added to mains water for plumbosolvency control has not been quantified to date. Using water company leakage rates, leak susceptibility and road network mapping, we quantify the total flux of P from leaking water mains in England and Wales at a 1km grid scale. This is validated against reported leaks for the UKs largest water utility. For 2014, we estimate the total flux of P from leaking mains to the environment to be c. 1.2ktP/year. Spatially, P flux is concentrated in urban areas where pipe density is highest, with major cities acting as a significant source of P (e.g. London into the Thames, with potentially 30% of total flux). The model suggests the majority (69%) of the P flux is likely to be to surface water. This is due to leakage susceptibility being a function of soil corrosivity and shrink-swell behaviour which are both controlled by presence of low-permeability clays. The location of major cities such as London close to the coast results in a potentially significant flux of P from mains leakage to estuarine environments. The contribution of leakage of phosphate dosed mains water should be considered in future source apportionment and ecosystem management. The methodology presented is generic and can be applied in other countries where phosphate dosing is undertaken or used prior to dosing during investment planning. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kot, C.A.; Srinivasan, M.G.; Hsieh, B.J.

    As part of the Phase II testing at the HDR Test Facility in Kahl/Main, FRG, two series of high-level seismic/vibrational experiments were performed. In the first of these (SHAG) a coast-down shaker, mounted on the reactor operating floor and capable of generating 1000 tonnes of force, was used to investigate full-scale structural response, soil-structure interaction (SSI), and piping/equipment response at load levels equivalent to those of a design basis earthquake. The HDR soil/structure system was tested to incipient failure exhibiting highly nonlinear response. In the load transmission from structure to piping/equipment significant response amplifications and shifts to higher frequencies occurred.more » The performance of various pipe support configurations was evaluated. This latter effort was continued in the second series of tests (SHAM), in which an in-plant piping system was investigated at simulated seismic loads (generated by two servo-hydraulic actuators each capable of generating 40 tonnes of force), that exceeded design levels manifold and resulted in considerable pipe plastification and failure of some supports (snubbers). The evaluation of six different support configurations demonstrated that proper system design (for a given spectrum) rather than number of supports or system stiffness is essential to limiting pipe stresses. Pipe strains at loads exceeding the design level eightfold were still tolerable, indicating that pipe failure even under extreme seismic loads is unlikely inspite of multiple support failures. Conservatively, an excess capacity (margin) of at least four was estimated for the piping system, and the pipe damping was found to be 4%. Comparisons of linear and nonlinear computational results with measurements showed that analytical predictions have wide scatter and do not necessarily yield conservative responses, underpredicting, in particular, peak support forces.« less

  18. Impact of the scale-up of piped water on urogenital schistosomiasis infection in rural South Africa

    PubMed Central

    Azongo, Daniel K; Vandormael, Alain; Bärnighausen, Till; Appleton, Christopher

    2018-01-01

    Recent work has estimated that sub-Saharan Africa could lose US$3.5 billion of economic productivity every year as a result of schistosomiasis and soil-transmitted helminthiasis. One of the main interventions to control schistosomiasis is the provision of safe water to limit the contact with infected water bodies and break the cycle of transmission. To date, a rigorous quantification of the impact of safe water supplies on schistosomiasis is lacking. Using data from one of Africa’s largest population-based cohorts, we establish the impact of the scale-up of piped water in a typical rural South African population over a seven-year time horizon. High coverage of piped water in the community decreased a child’s risk of urogenital schistosomiasis infection eight-fold (adjusted odds ratio = 0.12, 95% CI 0.06–0.26, p<0.001). The provision of safe water could drive levels of urogenital schistosomiasis infection to low levels of endemicity in rural African settings. PMID:29460779

  19. Impact of Casing Expansion on the Mechanical and Petro-Physical Properties of Wellbore Cements

    NASA Astrophysics Data System (ADS)

    Oyibo, A. E.

    2014-12-01

    The main objective of this research is to investigate the applicability of expandable casing technology as a remediation technique for leaky wells resulting in gas migration problems. Micro annulus is usually created at the cement-formation/cement-casing interface or within the cement matrix either due to poor primary cementing or as a result of activities such as temperature and pressure variation or fracturing operations. Recent reports on gas migration in hydraulically fractured wellbores, has raised concerns on the contamination of fresh water aquifers resulting from fluid migration though this flow path. A unique bench-scale physical model which utilizes expandable tubulars in the remediation of micro annular gas flow has been used to simulate expansion of a previously-cemented casing under field-like conditions. Three different designs of cement slurry: regular 16.4 lb. /gal, 16.4 lb. /gal base slurry foamed to 13 lb. /gal and 16.4 lb. /gal cement slurry with 10% salt concentration. Gas flow path (microannulus) was artificially created at the pipe-cement interface by rotating the inner pipe in a pipe inside pipe assembly with cement in the annulus within the first few hours of hydration to create debonding at the cement-casing interface. Nitrogen gas flow-through experiments were performed before and after the expansion to confirm the sealing of the microannulus. The results obtained confirmed the effectiveness of this technique in the complete closure of gas leakage path, providing seal-tight cement-formation interface free of microannulus. The manipulation of the cement sheath during the casing expansion resulted in improved porosity, permeability and the strength of the cement sheath. SEM micrographs revealed decrease in pore size and fracturing of unhydrated cement grains within the cement matrix. This technology has great potential to become one of the leading cement remediation techniques for leaks behind the casing if implemented. Keywords: Wellbore Integrity, Casing Expansion, Well Gas Leaks, CSH, Pore Collapse, Cement Pore Water.

  20. The structural significance of HAZ sigma phase formation in welded 25%Cr super duplex pipework

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wiesner, C.S.; Garwood, S.J.; Bowden, P.L.

    1993-12-31

    The welding of 25%Cr duplex stainless steel can lead to the formation of sigma phase in both weld metal and heat affected zone (HAZ) regions. It has generally been accepted that this can be avoided by the adoption of appropriate welding procedure controls, generally aimed at reducing heat input and promoting rapid cooling rates. However, experience during pipe spool fabrication for the Marathon East Brae Project has shown that it is extremely difficult to satisfy a welding specification requiring sigma free HAZs. This has proved a particular problem with thin wall pipe welds made in the 2G/5G or 6G fixedmore » positions, where the joint geometry reduces heat flow away from the weld and welding conditions tend to result in the use of higher heat inputs. This paper examines the effect of sigma phase on the fracture toughness of 25%Cr super duplex steel (UNS S32760). It is shown that the CTOD toughness at {minus}20 C decreases as soon as any sigma phase is present and continues to decrease with increasing sigma levels. The toughness of the sigmatized specimens produced by heat treatment was shown to be conservative compared to the toughness measured in the HAZ of 14.2mm and 7.1mm thick pipe weldments, made with welding parameters chosen to enhance HAZ sigma phase formation. Based on the CTOD versus percent sigma level relationship derived from the laboratory specimens, fracture assessment calculations of tolerable flaw sizes were performed. These demonstrated that under the severest design conditions, assuming the maximum flaw sizes which could remain undetected in the pipework, sigma levels up to 2.5% can be tolerated safely. The conservatism of the fracture assessments for predicting the performance of weldments was demonstrated by full scale tensile testing of 2 inch nominal bore x 2.77 mm wall thickness pipe butt welds containing through-thickness circumferential fatigue cracks located in the sigmatized HAZ.« less

  1. The "Long Pipe" in CICLoPE: A Design for Detailed Turbulence Measurements

    NASA Astrophysics Data System (ADS)

    Talamelli, A.; Bellani, G.; Rossetti, A.

    A new facility to study high Reynolds number wall bounded turbulent flow has been designed. It will be installed in the laboratory of Center for International Collaboration on Long Pipe Experiments "CICLoPE" in Predappio (Italy). The facility consists of a large pipe, allowing to reach high Reynolds numbers, where all turbulent scales can be resolved with standard measurement techniques. The pipe operates with air at ambient conditions with a maximum speed of 60 m/s in order to avoid any compressibility effect. In order to maintain stable conditions over long period of time the pipe is part of a close loop circuit. The pipe will be located in a tunnel 60 m underground, thus ensuring very low level of external perturbations. The layout resembles an ordinary wind tunnel where the main difference is the long test section, which produces most of the friction losses. This requires the use of a multiple stage axial fan driven by two independent motors. Even though many of the various aerodynamic components are similar to those ordinary used in wind tunnel (corners, diffusers, turbulence manipulators, contraction, etc.) they have been designed aiming at obtaining a very good quality of the flow and minimizing the overall pressure losses.

  2. Effect of flow rate and lead/copper pipe sequence on lead release from service lines.

    PubMed

    Cartier, Clément; Arnold, Roger B; Triantafyllidou, Simoni; Prévost, Michèle; Edwards, Marc

    2012-09-01

    A pilot experiment examined lead leaching from four representative configurations of service lines including: (1) 100% lead (Pb), (2) 100% copper (Cu), (3) 50% Pb upstream of 50% Cu, and (4) 50% Pb-downstream of 50% Cu using a range of flow rates. The cumulative mass of lead release indicated that a typical partial replacement configuration (50% lead downstream of copper) did not provide a net reduction in lead when compared to 100% lead pipe (85 mg for 50% Pb-downstream versus 83 mg for 100%-Pb) due to galvanic and deposition corrosion. The partially replaced service line configuration also had a much greater likelihood of producing water with "spikes" of lead particulates at higher flow rates, while tending to produce lower levels of lead at very low flow rates. After the first 214 days the galvanic current between copper and lead was only reduced by 34%, proving that galvanic impacts can be highly persistent even in water with optimized corrosion control by dosing of zinc orthophosphate. Finally, this experiment raises concern about the low flow rates used during some prior home sampling events, which may underestimate exposure to lead during normal water use, especially when galvanic Pb:Cu connections are present. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Mineral resource of the month: lead

    USGS Publications Warehouse

    Guberman, David E.

    2010-01-01

    The article discusses the properties and uses lead as a mineral resource. According to the author, lead is a corrosion-resistant, dense, ductile, and malleable blue-gray metal that has been used by humans for 5,000 years. Lead was first used in decorative, fixtures, roofs, pipes, and windows. The author says that lead is the fifth-most consumed metal based on tonnage after iron, aluminum, copper and zinc.

  4. Turbulent pipe flows subjected to temporal decelerations

    NASA Astrophysics Data System (ADS)

    Jeong, Wongwan; Lee, Jae Hwa

    2016-11-01

    Direct numerical simulations of temporally decelerating turbulent pipe flows were performed to examine effects of temporal decelerations on turbulence. The simulations were started with a fully developed turbulent pipe flow at a Reynolds number, ReD =24380, based on the pipe radius (R) and the laminar centerline velocity (Uc 0). Three different temporal decelerations were imposed to the initial flow with f= | d Ub / dt | =0.00127, 0.00625 and 0.025, where Ub is the bulk mean velocity. Comparison of Reynolds stresses and turbulent production terms with those for steady flow at a similar Reynolds number showed that turbulence is highly intensified with increasing f due to delay effects. Furthermore, inspection of the Reynolds shear stress profiles showed that strong second- and fourth-quadrant Reynolds shear stresses are greatly increased, while first- and third-quadrant components are also increased. Decomposition of streamwise Reynolds normal stress with streamwise cutoff wavelength (λx) 1 R revealed that the turbulence delay is dominantly originated from delay of strong large-scale turbulent structures in the outer layer, although small-scale motions throughout the wall layer adjusted more rapidly to the temporal decelerations. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2014R1A1A2057031).

  5. Laser propagation through full-scale, high-gain MagLIF gas pipes using the NIF

    NASA Astrophysics Data System (ADS)

    Pollock, Bradley; Sefkow, Adam; Goyon, Clement; Strozzi, David; Khan, Shahab; Rosen, Mordy; Campbell, Mike; Logan, Grant; Peterson, Kyle; Moody, John

    2016-10-01

    The first relevant measurements of laser propagation through surrogate high-gain MagLIF gas pipe targets at full scale have been performed at the NIF, using 30 kJ of laser drive from one quad in a 10 ns pulse at an intensity of 2e14 W/cm2. The unmagnetized pipe is filled with 1 atm of 99%/1% neopentane/Ar, and uses an entrance window of 0.75 um polyimide and an exit window of 0.3 um of Ta backed with 5 um of polyimide. Side-on x-ray emission from the plasma is imaged through the 100 um-thick epoxy wall onto a framing camera at four times during the drive, and is in excellent agreement with pre-shot HYDRA radiation-hydrodynamics modeling. X-ray emission from the Ta exit plane is imaged onto a streak camera to determine the timing and intensity of the laser burning through the pipe, and the Ar emission from the center of the pipe is spectrally- and temporally-resolved to determine the plasma electron temperature. Backscatter is measured throughout the laser drive, and is found to be of significance only when the laser reaches the Ta exit plane and produces SBS. These first results in unmagnetized surrogate gas fills are encouraging since they demonstrate sufficient laser energy absorption and low LPI losses within high-density long-scale-length plasmas for proposed high-gain MagLIF target designs. We will discuss plans to magnetize targets filled with high-density DT gas in future experiments. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.

  6. EFFECT OF BACTERIAL SULFATE REDUCTION ON IRON-CORROSION SCALES

    EPA Science Inventory

    Iron-sulfur geochemistry is important in many natural and engineered environments including drinking water systems. In the anaerobic environment beneath scales of corroding iron drinking water distribution system pipes, sulfate reducing bacteria (SRB) produce sulfide from natura...

  7. THE SIGNIFICANCE OF "STAGNATION CURVES" FOR LEAD AND COPPER, AND WATER QUALITY FACTORS AFFECTING THEM

    EPA Science Inventory

    "Stagnation curves" are the response of metal levels, particularly lead and copper, to time under conditions of no water flow. Research on lead pipe in the early 1980's in the United States, Germany, and in the United Kingdom suggested that they were characterized by rapid incre...

  8. Nuclear reactor heat transport system component low friction support system

    DOEpatents

    Wade, Elman E.

    1980-01-01

    A support column for a heavy component of a liquid metal fast breeder reactor heat transport system which will deflect when the pipes leading coolant to and from the heavy component expand or contract due to temperature changes includes a vertically disposed pipe, the pipe being connected to the heavy component by two longitudinally spaced cycloidal dovetail joints wherein the distal end of each of the dovetails constitutes a part of the surface of a large diameter cylinder and the centerlines of these large diameter cylinders intersect at right angles and the pipe being supported through two longitudinally spaced cycloidal dovetail joints wherein the distal end of each of the dovetails constitutes a part of the surface of a large diameter cylinder and the centerlines of these large diameter cylinders intersect at right angles, each of the cylindrical surfaces bearing on a flat and horizontal surface.

  9. An experimental study of geyser-like flows induced by a pressurized air pocket

    NASA Astrophysics Data System (ADS)

    Elayeb, I. S.; Leon, A.; Choi, Y.; Alnahit, A. O.

    2015-12-01

    Previous studies argues that the entrapment of pressurized air pockets within combined sewer systems can produce geyser flows, which is an oscillating jetting of a mixture of gas-liquid flows. To verify that pressurized air pockets can effectively produce geysers, laboratory experiments were conducted. However, past experiments were conducted in relatively small-scale apparatus (i.e. maximum φ2" vertical shaft). This study conducted a set of experiments in a larger apparatus. The experimental setup consists of an upstream head tank, a downstream head tank, a horizontal pipe (46.5ft long, φ6") and a vertical pipe (10ft long, φ6"). The initial condition for the experiments is constant flow discharge through the horizontal pipe. The experiments are initiated by injecting an air pocket with pre-determined volume and pressure at the upstream end of the horizontal pipe. The air pocket propagates through the horizontal pipe until it arrives to the vertical shaft, where it is released producing a geyser-like flow. Three flow rates in the horizontal pipe and three injected air pressures were tested. The variables measured were pressure at two locations in the horizontal pipe and two locations in the vertical pipe. High resolution videos at two regions in the vertical shaft were also recorded. To gain further insights in the physics of air-water interaction, the laboratory experiments were complemented with numerical simulations conducted using a commercial 3D CFD model, previously validated with experiments.

  10. Reynolds stress scaling in pipe flow turbulence—first results from CICLoPE

    PubMed Central

    Fiorini, T.; Bellani, G.; Talamelli, A.

    2017-01-01

    This paper reports the first turbulence measurements performed in the Long Pipe Facility at the Center for International Cooperation in Long Pipe Experiments (CICLoPE). In particular, the Reynolds stress components obtained from a number of straight and boundary-layer-type single-wire and X-wire probes up to a friction Reynolds number of 3.8×104 are reported. In agreement with turbulent boundary-layer experiments as well as with results from the Superpipe, the present measurements show a clear logarithmic region in the streamwise variance profile, with a Townsend–Perry constant of A2≈1.26. The wall-normal variance profile exhibits a Reynolds-number-independent plateau, while the spanwise component was found to obey a logarithmic scaling over a much wider wall-normal distance than the other two components, with a slope that is nearly half of that of the Townsend–Perry constant, i.e. A2,w≈A2/2. The present results therefore provide strong support for the scaling of the Reynolds stress tensor based on the attached-eddy hypothesis. Intriguingly, the wall-normal and spanwise components exhibit higher amplitudes than in previous studies, and therefore call for follow-up studies in CICLoPE, as well as other large-scale facilities. This article is part of the themed issue ‘Toward the development of high-fidelity models of wall turbulence at large Reynolds number’. PMID:28167586

  11. Submarine pipeline on-bottom stability. Volume 2: Software and manuals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1998-12-01

    The state-of-the-art in pipeline stability design has been changing very rapidly recent. The physics governing on-bottom stability are much better understood now than they were eight years. This is due largely because of research and large scale model tests sponsored by PRCI. Analysis tools utilizing this new knowledge have been developed. These tools provide the design engineer with a rational approach have been developed. These tools provide the design engineer with a rational approach for weight coating design, which he can use with confidence because the tools have been developed based on full scale and near full scale model tests.more » These tools represent the state-of-the-art in stability design and model the complex behavior of pipes subjected to both wave and current loads. These include: hydrodynamic forces which account for the effect of the wake (generated by flow over the pipe) washing back and forth over the pipe in oscillatory flow; and the embedment (digging) which occurs as a pipe resting on the seabed is exposed to oscillatory loadings and small oscillatory deflections. This report has been developed as a reference handbook for use in on-bottom pipeline stability analysis It consists of two volumes. Volume one is devoted descriptions of the various aspects of the problem: the pipeline design process; ocean physics, wave mechanics, hydrodynamic forces, and meteorological data determination; geotechnical data collection and soil mechanics; and stability design procedures. Volume two describes, lists, and illustrates the analysis software. Diskettes containing the software and examples of the software are also included in Volume two.« less

  12. [Research on controlling iron release of desalted water transmitted in existing water distribution system].

    PubMed

    Tian, Yi-Mei; Liu, Yang; Zhao, Peng; Shan, Jin-Lin; Yang, Suo-Yin; Liu, Wei

    2012-04-01

    Desalted water, with strong corrosion characteristics, would possibly lead to serious "red water" when transmitted and distributed in existing municipal water distribution network. The main reason for red water phenomenon is iron release in water pipes. In order to study the methods of controlling iron release in existing drinking water distribution pipe, tubercle analysis of steel pipe and cast iron pipe, which have served the distribution system for 30-40 years, was carried out, the main construction materials were Fe3O4 and FeOOH; and immersion experiments were carried in more corrosive pipes. Through changing mixing volume of tap water and desalted water, pH, alkalinity, chloride and sulfate, the influence of different water quality indexes on iron release were mainly analyzed. Meanwhile, based on controlling iron content, water quality conditions were established to meet with the safety distribution of desalted water: volume ratio of potable water and desalted water should be higher than or equal to 2, pH was higher than 7.6, alkalinity was higher than 200 mg x L(-1).

  13. Intermittent gravity-driven flow of grains through narrow pipes

    NASA Astrophysics Data System (ADS)

    Alvarez, Carlos A.; de Moraes Franklin, Erick

    2017-01-01

    Grain flows through pipes are frequently found in various settings, such as in pharmaceutical, chemical, petroleum, mining and food industries. In the case of size-constrained gravitational flows, density waves consisting of alternating high- and low-compactness regions may appear. This study investigates experimentally the dynamics of density waves that appear in gravitational flows of fine grains through vertical and slightly inclined pipes. The experimental device consisted of a transparent glass pipe through which different populations of glass spheres flowed driven by gravity. Our experiments were performed under controlled ambient temperature and relative humidity, and the granular flow was filmed with a high-speed camera. Experimental results concerning the length scales and celerities of density waves are presented, together with a one-dimensional model and a linear stability analysis. The analysis exhibits the presence of a long-wavelength instability, with the most unstable mode and a cut-off wavenumber whose values are in agreement with the experimental results.

  14. Feasibility study of a passive aeration reactor equipped with vertical pipes for compost stabilization of cow manure.

    PubMed

    Sylla, Youssouf Boundou; Kuroda, Masao; Yamada, Masayuki; Matsumoto, Naoko

    2006-10-01

    Pilot-scale composting was carried out with cow manure to evaluate the performances of two passive aeration systems: a conventional passive aeration system equipped with horizontal pipes and an unusual passive aeration method based on air delivery by means of vertical pipes. The effects of both types of passive aeration apparatus were investigated in order to determine the degree of composting rate by continuously monitoring temperature, moisture content, organic matter, electrical conductivity, pH and C/N ratio in the piles. Temperatures in the range of thermophily (55-65 degrees C) were reached in all runs within 1-2 days then lasting for about 1 week, a span long enough for pathogen abatement. Results suggest that passive aeration carried out by vertical pipes is more effective for air delivery into compost piles than conventional passive aeration of air adduction with horizontal pipes. The variation in the number of vertical pipes was revealed to be an important parameter for the control of composting rate and temperature. Composting rates estimated from the heat balance equation were substantially in agreement with those computed through the conversion ratio of total organic matter decrement. The conversion ratios and composting rates obtained in this study using passive aeration with vertical pipes were well aligned with those found using forced air delivery systems.

  15. Protection of Buried Pipe under Repeated Loading by Geocell Reinforcement

    NASA Astrophysics Data System (ADS)

    Khalaj, Omid; Joz Darabi, N.; Moghaddas Tafreshi, S. N.; Mašek, Bohuslav

    2017-12-01

    With increase in cities’ population and development of urbane life, passing buried pipelines near ground’s surface is inevitable in urban areas, roads, subways and highways. This paper presents the results of three-dimensional full scale model tests on high-density polyethylene (HDPE) pipe with diameter of 250 mm in geocell reinforced soil, subjected to repeated loading to simulate the vehicle loads. The effect of geocell’s pocket size (55*55 mm and 110*110 mm) and embedment depth of buried pipe (1.5 and 2 times pipe diameter) in improving the behaviour of buried pipes was investigated. The geocell’s height of 100 mm was used in all tests. The repeated load of 800 kPa was applied on circular loading plate with diameter of 250 mm. The results show that the pipe displacement, soil surface settlement and transferred pressure on the pipe’s crown has been influenced significantly upon the use of geocells. For example, the vertical diametric strain (VDS) and soil surface settlement (SSS), in a way that using a geocell with pocket size of 110*110 mm reduces by 27% and 43%, respectively, compared with the unreinforced one. Meanwhile, by increasing buried depth of pipe from 1.5D to 2D, the use of geocell of 110*110 mm delivers about 50% reduction in SSS and VDS, compared with the unreinforced soil.

  16. Features of the gas dynamics and local heat transfer in intake system of piston engine with supercharging

    NASA Astrophysics Data System (ADS)

    Plotnikov, L. V.

    2017-09-01

    Comparison of experimental research results of gas dynamics and instantaneous local heat transfer in the intake pipes for piston internal combustion engines (ICE) without and with supercharging are presented in the article. Studies were conducted on full-scale experimental setups in terms of gas dynamic nonstationarity, which is characteristic of piston engines. It has been established that the turbocharger installation in a gas-air system of piston internal combustion engine leads to significant differences in the patterns of change in gas-dynamic and heat transfer characteristics of flows. These data can be used in a modernization of piston engines due to installation of a turbocharger or in a development of gas-air systems for piston ICE with supercharging.

  17. In-pipe aerodynamic characteristics of a projectile in comparison with free flight for transonic Mach numbers

    NASA Astrophysics Data System (ADS)

    Hruschka, R.; Klatt, D.

    2018-03-01

    The transient shock dynamics and drag characteristics of a projectile flying through a pipe 3.55 times larger than its diameter at transonic speed are analyzed by means of time-of-flight and pipe wall pressure measurements as well as computational fluid dynamics (CFD). In addition, free-flight drag of the 4.5-mm-pellet-type projectile was also measured in a Mach number range between 0.5 and 1.5, providing a means for comparison against in-pipe data and CFD. The flow is categorized into five typical regimes the in-pipe projectile experiences. When projectile speed and hence compressibility effects are low, the presence of the pipe has little influence on the drag. Between Mach 0.5 and 0.8, there is a strong drag increase due to the presence of the pipe, however, up to a value of about two times the free-flight drag. This is exactly where the nose-to-base pressure ratio of the projectile becomes critical for locally sonic speed, allowing the drag to be estimated by equations describing choked flow through a converging-diverging nozzle. For even higher projectile Mach numbers, the drag coefficient decreases again, to a value slightly below the free-flight drag at Mach 1.5. This behavior is explained by a velocity-independent base pressure coefficient in the pipe, as opposed to base pressure decreasing with velocity in free flight. The drag calculated by CFD simulations agreed largely with the measurements within their experimental uncertainty, with some discrepancies remaining for free-flying projectiles at supersonic speed. Wall pressure measurements as well as measured speeds of both leading and trailing shocks caused by the projectile in the pipe also agreed well with CFD.

  18. Effectiveness of distributed temperature measurements for early detection of piping in river embankments

    NASA Astrophysics Data System (ADS)

    Bersan, Silvia; Koelewijn, André R.; Simonini, Paolo

    2018-02-01

    Internal erosion is the cause of a significant percentage of failure and incidents involving both dams and river embankments in many countries. In the past 20 years the use of fibre-optic Distributed Temperature Sensing (DTS) in dams has proved to be an effective tool for the detection of leakages and internal erosion. This work investigates the effectiveness of DTS for dike monitoring, focusing on the early detection of backward erosion piping, a mechanism that affects the foundation layer of structures resting on permeable, sandy soils. The paper presents data from a piping test performed on a large-scale experimental dike equipped with a DTS system together with a large number of accompanying sensors. The effect of seepage and piping on the temperature field is analysed, eventually identifying the processes that cause the onset of thermal anomalies around piping channels and thus enable their early detection. Making use of dimensional analysis, the factors that influence this thermal response of a dike foundation are identified. Finally some tools are provided that can be helpful for the design of monitoring systems and for the interpretation of temperature data.

  19. Design trade-offs among shunt current, pumping loss and compactness in the piping system of a multi-stack vanadium flow battery

    NASA Astrophysics Data System (ADS)

    Ye, Qiang; Hu, Jing; Cheng, Ping; Ma, Zhiqi

    2015-11-01

    Trade-off between shunt current loss and pumping loss is a major challenge in the design of the electrolyte piping network in a flow battery system. It is generally recognized that longer and thinner ducts are beneficial to reduce shunt current but detrimental to minimize pumping power. Base on the developed analog circuit model and the flow network model, we make case studies of multi-stack vanadium flow battery piping systems and demonstrate that both shunt current and electrolyte flow resistance can be simultaneously minimized by using longer and thicker ducts in the piping network. However, extremely long and/or thick ducts lead to a bulky system and may be prohibited by the stack structure. Accordingly, the intrinsic design trade-off is between system efficiency and compactness. Since multi-stack configurations bring both flexibility and complexity to the design process, we perform systematic comparisons among representative piping system designs to illustrate the complicated trade-offs among numerous parameters including stack number, intra-stack channel resistance and inter-stack pipe resistance. As the final design depends on various technical and economical requirements, this paper aims to provide guidelines rather than solutions for designers to locate the optimal trade-off points according to their specific cases.

  20. Smart Pipes—Instrumented Water Pipes, Can This Be Made a Reality?

    PubMed Central

    Metje, Nicole; Chapman, David N.; Cheneler, David; Ward, Michael; Thomas, Andrew M.

    2011-01-01

    Several millions of kilometres of pipes and cables are buried beneath our streets in the UK. As they are not visible and easily accessible, the monitoring of their integrity as well as the quality of their contents is a challenge. Any information of these properties aids the utility owners in their planning and management of their maintenance regime. Traditionally, expensive and very localised sensors are used to provide irregular measurements of these properties. In order to have a complete picture of the utility network, cheaper sensors need to be investigated which would allow large numbers of small sensors to be incorporated into (or near to) the pipe leading to so-called smart pipes. This paper focuses on a novel trial where a short section of a prototype smart pipe was buried using mainly off-the-shelf sensors and communication elements. The challenges of such a burial are presented together with the limitations of the sensor system. Results from the sensors were obtained during and after burial indicating that off-the-shelf sensors can be used in a smart pipes system although further refinements are necessary in order to miniaturise these sensors. The key challenges identified were the powering of these sensors and the communication of the data to the operator using a range of different methods. PMID:22164027

  1. IN-HOUSE COPPER AND LEAD SOLUBILITY/CORROSION STUDIES

    EPA Science Inventory

    Understanding and predicting metal release from pipes of all sizes and types from the treatment plant to the consumer’s tap is critical, specifically for regulatory compliance with the Lead and Copper Rule, as well as the performance, corrosion morphology, and longevity of infras...

  2. Numerical Analysis on Effect of Areal Gas Distribution Pipe on Characteristics Inside COREX Shaft Furnace

    NASA Astrophysics Data System (ADS)

    Wu, Shengli; Du, Kaiping; Xu, Jian; Shen, Wei; Kou, Mingyin; Zhang, Zhekai

    2014-07-01

    In recent years, two parallel pipes of areal gas distribution (AGD) were installed into the COREX shaft furnace to improve the furnace efficiency. A three-dimensional mathematical model at steady state, which takes a modified three-interface unreacted core model into consideration, is developed in the current work to describe the effect of the AGD pipe on the inner characteristics of shaft furnace. The accuracy of the model is evaluated using the plant operational data. The AGD pipe effectively improves the uniformity of reducing gas distribution, which leads to an increase in gas temperature and concentration of CO or H2 around the AGD pipe, and hence it further contributes to the iron oxide reduction. As a result, the top gas utilization rate and the solid metallization rate (MR) at the bottom outlet are increased by 0.015 and 0.11, respectively. In addition, the optimizations of the flow volume ratio (FVR) of the reducing gas fed through the AGD inlet and the AGD pipe arrangement are further discussed based on the gas flow distribution and the solid MR. Despite the relative suitability of the current FVR (60%), it is still meaningful to enable a manual adjustment of FVR, instead of having it driven by pressure difference, to solve certain production problems. On the other hand, considering the flatter distribution of gas flow, the higher solid MR, and easy installation and replacement, the cross distribution arrangement of AGD pipe with a length of 3 m is recommended to replace the current AGD pipe arrangement.

  3. Computational analysis of fluid dynamics in pharmaceutical freeze-drying.

    PubMed

    Alexeenko, Alina A; Ganguly, Arnab; Nail, Steven L

    2009-09-01

    Analysis of water vapor flows encountered in pharmaceutical freeze-drying systems, laboratory-scale and industrial, is presented based on the computational fluid dynamics (CFD) techniques. The flows under continuum gas conditions are analyzed using the solution of the Navier-Stokes equations whereas the rarefied flow solutions are obtained by the direct simulation Monte Carlo (DSMC) method for the Boltzmann equation. Examples of application of CFD techniques to laboratory-scale and industrial scale freeze-drying processes are discussed with an emphasis on the utility of CFD for improvement of design and experimental characterization of pharmaceutical freeze-drying hardware and processes. The current article presents a two-dimensional simulation of a laboratory scale dryer with an emphasis on the importance of drying conditions and hardware design on process control and a three-dimensional simulation of an industrial dryer containing a comparison of the obtained results with analytical viscous flow solutions. It was found that the presence of clean in place (CIP)/sterilize in place (SIP) piping in the duct lead to significant changes in the flow field characteristics. The simulation results for vapor flow rates in an industrial freeze-dryer have been compared to tunable diode laser absorption spectroscopy (TDLAS) and gravimetric measurements.

  4. PBF Cooling Tower. View from highbay roof of Reactor Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PBF Cooling Tower. View from high-bay roof of Reactor Building (PER-620). Camera faces northwest. East louvered face has been installed. Inlet pipes protrude from fan deck. Two redwood vents under construction at top. Note piping, control, and power lines at sub-grade level in trench leading to Reactor Building. Photographer: Kirsh. Date: June 6, 1969. INEEL negative no. 69-3466 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

  5. A loose bolt delays loading of Endeavour's external tank

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This view shows the pipe (center top) leading toward Endeavour from the side of the White Room at Launch Pad 39B. A loose bracket observed hanging down from the pipe delayed loading of Endeavour's external tank by several hours to allow technicians to remove it. A 'U' bolt connects the bracket to a fire suppression water line attached to the exterior of the White Room. The loose bolt could have possibly created a debris hazard.

  6. GEOCHEMISTRY OF SULFUR IN IRON CORROSION SCALES FOUND IN DRINKING WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    Iron-sulfur geochemistry is important in many natural and engineered environments, including drinking water systems. In the anaerobic environment beneath scales of corroding iron drinking water distribution system pipes, sulfate reducing bacteria (SRB) produce sulfide from natu...

  7. Modeling MIC copper release from drinking water pipes.

    PubMed

    Pizarro, Gonzalo E; Vargas, Ignacio T; Pastén, Pablo A; Calle, Gustavo R

    2014-06-01

    Copper is used for household drinking water distribution systems given its physical and chemical properties that make it resistant to corrosion. However, there is evidence that, under certain conditions, it can corrode and release unsafe concentrations of copper to the water. Research on drinking water copper pipes has developed conceptual models that include several physical-chemical mechanisms. Nevertheless, there is still a necessity for the development of mathematical models of this phenomenon, which consider the interaction among physical-chemical processes at different spatial scales. We developed a conceptual and a mathematical model that reproduces the main processes in copper release from copper pipes subject to stagnation and flow cycles, and corrosion is associated with biofilm growth on the surface of the pipes. We discuss the influence of the reactive surface and the copper release curves observed. The modeling and experimental observations indicated that after 10h stagnation, the main concentration of copper is located close to the surface of the pipe. This copper is associated with the reactive surface, which acts as a reservoir of labile copper. Thus, for pipes with the presence of biofilm the complexation of copper with the biomass and the hydrodynamics are the main mechanisms for copper release. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Sensory aspects of drinking water in contact with epoxy lined copper pipe.

    PubMed

    Heim, T H; Dietrich, A M

    2007-01-01

    Pipe relining via in situ epoxy lining is used to remediate corroded plumbing or distribution systems. This investigation examined the effects on odour, TOC, THM formation and disinfectant demand in water exposed to epoxy-lined copper pipes used for home plumbing. The study was conducted in accordance with the Utility Quick Test, a migration/leaching method for utilities to conduct sensory analysis of materials in contact with drinking water. The test was performed using water with no disinfectant and levels of chlorine and monochloramines representative of those found in the distribution system. Panelists repeatedly and consistently described a "plastic/adhesive/putty" odour in the water from the pipes. The odour intensity remained relatively constant for each of two subsequent flushes. Water samples stored in the epoxy-lined pipes showed a significant increase in the leaching of organic compounds (as TOC), and this TOC was demonstrated to react with free chlorine to form trichloromethane. Water stored in the pipes also showed a marked increase in disinfectant demand relative to the water stored in glass control flasks. A study conducted at a full scale installation at an apartment demonstrated that after installation and regular use, the epoxy lining did not yield detectable differences in water quality.

  9. Comparison of three corrosion inhibitors in simulated partial lead service line replacements.

    PubMed

    Kogo, Aki; Payne, Sarah Jane; Andrews, Robert C

    2017-05-05

    Partial lead service line replacements (PLSLR) were simulated using five recirculating pipe loops treated with either zinc orthophosphate (1mg/L as P), orthophosphate (1mg/L as P) or sodium silicate (10mg/L). Two pipe loops served as ⿿inhibitor-free⿿ (Pb-Cu) and ⿿galvanic free⿿ (Pb-PVC) controls. Changes in water quality (CSMR [0.2 or 1], conductivity [⿿330mS/cm or ⿿560mS/cm], chlorine [1.4mg/L]) were not observed to provide a significant impact on lead or copper release, although galvanic corrosion was shown to be a driving factor. Generally, both orthophosphate and zinc orthophosphate provided better corrosion control for both total and dissolved lead (30min, 6h, 65h) and copper (30min, 6h), when compared to either the inhibitor-free control or the sodium silicate treated system. This work highlights the importance of understanding the complex interplay of corrosion inhibitors on particulate and dissolved species when considering both lead and copper. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Application of CdZnTe Gamma-Ray Detector for Imaging Corrosion under Insulation

    NASA Astrophysics Data System (ADS)

    Abdullah, J.; Yahya, R.

    2007-05-01

    Corrosion under insulation (CUI) on the external wall of steel pipes is a common problem in many types of industrial plants. This is mainly due to the presence of moisture or water in the insulation materials. This type of corrosion can cause failures in areas that are not normally of a primary concern to an inspection program. The failures are often the result of localised corrosion and not general wasting over a large area. These failures can tee catastrophic in nature or at least have an adverse economic effect in terms of downtime and repairs. There are a number of techniques used today for CUI investigations. The main ones are profile radiography, pulse eddy current, ultrasonic spot readings and insulation removal. A new system now available is portable Pipe-CUI-Profiler. The nucleonic system is based on dual-beam gamma-ray absorption technique using Cadmium Zinc Telluride (CdZnTe) semiconductor detectors. The Pipe-CUI-Profiler is designed to inspect pipes of internal diameter 50, 65, 80, 90, 100, 125 and 150 mm. Pipeline of these sizes with aluminium or thin steel sheathing, containing fibreglass or calcium silicate insulation to thickness of 25, 40 and 50 mm can be inspected. The system has proven to be a safe, fast and effective method of inspecting pipe in industrial plant operations. This paper describes the application of gamma-ray techniques and CdZnTe semiconductor detectors in the development of Pipe-CUI-Profiler for non-destructive imaging of corrosion under insulation of steel pipes. Some results of actual pipe testing in large-scale industrial plant will be presented.

  11. Bacterial community changes in copper and PEX drinking water pipeline biofilms under extra disinfection and magnetic water treatment.

    PubMed

    Inkinen, J; Jayaprakash, B; Ahonen, M; Pitkänen, T; Mäkinen, R; Pursiainen, A; Santo Domingo, J W; Salonen, H; Elk, M; Keinänen-Toivola, M M

    2018-02-01

    To study the stability of biofilms and water quality in pilot scale drinking water copper and PEX pipes in changing conditions (extra disinfection, magnetic water treatment, MWT). Next-generation sequencing (NGS) of 16S ribosomal RNA genes (rDNA) to describe total bacterial community and ribosomal RNA (rRNA) to describe active bacterial members in addition to traditional microbiological methods were applied. Biofilms from control copper and PEX pipes shared same most abundant bacteria (Methylobacterium spp., Sphingomonas spp., Zymomonas spp.) and average species diversities (Shannon 3·8-4·2) in rDNA and rRNA libraries, whereas few of the taxa differed by their abundance such as lower total Mycobacterium spp. occurrence in copper (<0·02%) to PEX (<0·2%) pipes. Extra disinfection (total chlorine increase from c. 0·5 to 1 mg l -1 ) affected total and active population in biofilms seen as decrease in many bacterial species and diversity (Shannon 2·7, P < 0·01, rRNA) and increase in Sphingomonas spp. as compared to control samples. Furthermore, extra-disinfected copper and PEX samples formed separate clusters in unweighted non-metric multidimensional scaling plot (rRNA) similarly to MWT-treated biofilms of copper (but not PEX) pipes that instead showed higher species diversity (Shannon 4·8, P < 0·05 interaction). Minor chlorine dose addition increased selection pressure and many species were sensitive to chlorination. Pipe material seemed to affect mycobacteria occurrence, and bacterial communities with MWT in copper but not in PEX pipes. This study using rRNA showed that chlorination affects especially active fraction of bacterial communities. Copper and PEX differed by the occurrence of some bacterial members despite similar community profiles. © 2017 The Society for Applied Microbiology.

  12. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

    PubMed

    Ji, Pan; Parks, Jeffrey; Edwards, Marc A; Pruden, Amy

    2015-01-01

    A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  13. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome

    PubMed Central

    Ji, Pan; Parks, Jeffrey; Edwards, Marc A.; Pruden, Amy

    2015-01-01

    A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO4 2- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9–10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome. PMID:26495985

  14. Ball feeder for replenishing evaporator feed

    DOEpatents

    Felde, David K.; McKoon, Robert H.

    1993-01-01

    Vapor source material such as uranium, which is to be dropped into a melt in an evaporator, is made into many balls of identical diameters and placed inside a container. An elongated sloping pipe is connected to the container and leads to the evaporator such that these balls can travel sequentially therealong by gravity. A metering valve in this pipe for passing these balls one at a time is opened in response to a signal when it is ascertained by a detector that there is a ball ready to be passed. A gate in the pipe near the evaporator momentarily stops the motion of the traveling ball and is then opened to allow the ball drop into the melt at a reduced speed.

  15. Ball feeder for replenishing evaporator feed

    DOEpatents

    Felde, D.K.; McKoon, R.H.

    1993-03-23

    Vapor source material such as uranium, which is to be dropped into a melt in an evaporator, is made into many balls of identical diameters and placed inside a container. An elongated sloping pipe is connected to the container and leads to the evaporator such that these balls can travel sequentially therealong by gravity. A metering valve in this pipe for passing these balls one at a time is opened in response to a signal when it is ascertained by a detector that there is a ball ready to be passed. A gate in the pipe near the evaporator momentarily stops the motion of the traveling ball and is then opened to allow the ball drop into the melt at a reduced speed.

  16. High Content of Lead Is Associated with the Softness of Drinking Water and Raised Cardiovascular Morbidity: A Review.

    PubMed

    Bjørklund, Geir; Dadar, Maryam; Chirumbolo, Salvatore; Aaseth, Jan

    2018-04-14

    Daily ingestion of lead (Pb), even through piped drinking water, has long time been an important issue of concern, attracting for decades research in environmental science and toxicology, and again comes to prominence because of recent high-profile cases of exposure of populations in several countries to Pb-contaminated water. Numerous studies have reported an association between Pb in water and the risk of cardiovascular pathologies. Low levels of magnesium and calcium, i.e., low degree of hardness of the drinking water, may accentuate Pb leaching from water pipes and furthermore increase Pb absorption. This review evaluates the evidence for an association between Pb exposure from drinking water and cardiovascular end points in human populations.

  17. COPPER PITTING CORROSION AND PINHOLE LEAKS: A CASE STUDY

    EPA Science Inventory

    Localized corrosion, or "pitting", of copper drinking water pipe continues is a problem for many water utilities and their customers. Extreme attack leads to pinhole leaks that can potentially lead to water damage, mold growth, and costly repairs for the homeowners, as well as th...

  18. Struvite scale formation and control.

    PubMed

    Parsons, S A; Doyle, J D

    2004-01-01

    Struvite scale formation is a major operational issue at both conventional and biological nutrient removal wastewater treatment plants. Factors affecting the formation of struvite scales were investigated including supersaturation, pH and pipe material and roughness. A range of control methods have been investigated including low fouling materials, pH control, inhibitor and chemical dosing. Control methods exist to reduce scale formation although each has its advantages and disadvantages.

  19. Investigation of scaling characteristics for defining design environments due to transient ground winds and near-field, nonlinear acoustic fields

    NASA Technical Reports Server (NTRS)

    Shih, C. C.

    1973-01-01

    In order to establish a foundation of scaling laws for the highly nonlinear waves associated with the launch vehicle, the basic knowledge of the relationships among the paramaters pertinent to the energy dissipation process associated with the propagation of nonlinear pressure waves in thermoviscous media is required. The problem of interest is to experimentally investigate the temporal and spacial velocity profiles of fluid flow in a 3-inch open-end pipe of various lengths, produced by the propagation of nonlinear pressure waves for various diaphragm burst pressures of a pressure wave generator. As a result, temporal and spacial characteristics of wave propagation for a parametric set of nonlinear pressure waves in the pipe containing air under atmospheric conditions were determined. Velocity measurements at five sections along the pipes of up to 210 ft. in length were made with hot-film anemometers for five pressure waves produced by a piston. The piston was derived with diaphragm burst pressures at 20, 40, 60, 80 and 100 psi in the driver chamber of the pressure wave generator.

  20. Reynolds stress scaling in pipe flow turbulence-first results from CICLoPE.

    PubMed

    Örlü, R; Fiorini, T; Segalini, A; Bellani, G; Talamelli, A; Alfredsson, P H

    2017-03-13

    This paper reports the first turbulence measurements performed in the Long Pipe Facility at the Center for International Cooperation in Long Pipe Experiments (CICLoPE). In particular, the Reynolds stress components obtained from a number of straight and boundary-layer-type single-wire and X-wire probes up to a friction Reynolds number of 3.8×10 4 are reported. In agreement with turbulent boundary-layer experiments as well as with results from the Superpipe, the present measurements show a clear logarithmic region in the streamwise variance profile, with a Townsend-Perry constant of A 2 ≈1.26. The wall-normal variance profile exhibits a Reynolds-number-independent plateau, while the spanwise component was found to obey a logarithmic scaling over a much wider wall-normal distance than the other two components, with a slope that is nearly half of that of the Townsend-Perry constant, i.e. A 2,w ≈A 2 /2. The present results therefore provide strong support for the scaling of the Reynolds stress tensor based on the attached-eddy hypothesis. Intriguingly, the wall-normal and spanwise components exhibit higher amplitudes than in previous studies, and therefore call for follow-up studies in CICLoPE, as well as other large-scale facilities.This article is part of the themed issue 'Toward the development of high-fidelity models of wall turbulence at large Reynolds number'. © 2017 The Author(s).

  1. Failure analysis of a Stirling engine heat pipe

    NASA Technical Reports Server (NTRS)

    Moore, Thomas J.; Cairelli, James E.; Khalili, Kaveh

    1989-01-01

    Failure analysis was conducted on a heat pipe from a Stirling Engine test rig which was designed to operate at 1073 K. Premature failure had occurred due to localized overheating at the leading edge of the evaporator fin. It was found that a crack had allowed air to enter the fin and react with the sodium coolant. The origin of the crack was found to be located at the inner surface of the Inconel 600 fin where severe intergranular corrosion had taken place.

  2. Monitoring Conditions Leading to SCC/Corrosion of Carbon Steel in Fuel Grade Ethanol

    DOT National Transportation Integrated Search

    2011-02-11

    This is the draft final report of the project on field monitoring of conditions that lead to SCC in ethanol tanks and piping. The other two aspects of the consolidated program, ethanol batching and blending effects (WP#325) and source effects (WP#323...

  3. Analysis of BF Hearth Reasonable Cooling System Based on the Water Dynamic Characteristics

    NASA Astrophysics Data System (ADS)

    Zuo, Haibin; Jiao, Kexin; Zhang, Jianliang; Li, Qian; Wang, Cui

    A rational cooling water system is the assurance for long campaign life of blast furnace. In the paper, the heat transfer of different furnace period and different furnace condition based on the water quality characteristics were analysed, and the reason of the heat flux over the normal from the hydrodynamics was analysed. The results showed that, the vapour-film and scale existence significantly influenced the hearth heat transfer, which accelerated the brick lining erosion. The water dynamic characteristics of the parallel inner pipe or among the pipes were the main reason for the abnormal heat flux and film boiling. As to the reasonable cooling water flow, the gas film and the scale should be controlled and the energy saving should be considered.

  4. Thermographic identification of wetted insulation on pipelines in the arctic oilfields

    NASA Astrophysics Data System (ADS)

    Miles, Jonathan J.; Dahlquist, A. L.; Dash, L. C.

    2006-04-01

    Steel pipes used at Alaskan oil-producing facilities to transport production crude, gas, and injection water between well house and drill site manifold building, and along cross-country lines to and from central processing facilities, must be insulated in order to protect against the severely cold temperatures that are common during the arctic winter. A problem inherent with this system is that the sealed joints between adjacent layers of the outer wrap will over time degrade and can allow water to breach the system and migrate into and through the insulation. The moisture can ultimately interact with the steel pipe and trigger external corrosion which, if left unchecked, can lead to pipe failure and spillage. A New Technology Evaluation Guideline prepared for ConocoPhillips Alaska, Inc. in 2001 is intended to guide the consideration of new technologies for pipeline inspection in a manner that is safer, faster, and more cost-effective than existing techniques. Infrared thermography (IRT) was identified as promising for identification of wetted insulation regions given that it offers the means to scan a large area quickly from a safe distance, and measure the temperature field associated with that area. However, it was also recognized that there are limiting factors associated with an IRT-based approach including instrument sensitivity, cost, portability, functionality in hostile (arctic) environments, and training required for proper interpretation of data. A methodology was developed and tested in the field that provides a technique to conduct large-scale screening for wetted regions along insulated pipelines. The results of predictive modeling analysis and testing demonstrate the feasibility under certain condition of identifying wetted insulation areas. The results of the study and recommendations for implementation are described.

  5. Baseline experimental investigation of an electrohydrodynamically assisted heat pipe

    NASA Technical Reports Server (NTRS)

    Duncan, A. B.

    1995-01-01

    The increases in power demand and associated thermal management requirements of future space programs such as potential Lunar/Mars missions will require enhancing the operating efficiencies of thermal management devices. Currently, the use of electrohydrodynamically (EHD) assisted thermal control devices is under consideration as a potential method of increasing thermal management system capacity. The objectives of the currently described investigation included completing build-up of the EHD-Assisted Heat Pipe Test bed, developing test procedures for an experimental evaluation of the unassisted heat pipe, developing an analytical model capable of predicting the performance limits of the unassisted heat pipe, and obtaining experimental data which would define the performance characteristics of the unassisted heat pipe. The information obtained in the currently proposed study will be used in order to provide extensive comparisons with the EHD-assisted performance observations to be obtained during the continuing investigation of EHD-Assisted heat transfer devices. Through comparisons of the baseline test bed data and the EHD assisted test bed data, accurate insight into the performance enhancing characteristics of EHD augmentation may be obtained. This may lead to optimization, development, and implementation of EHD technology for future space programs.

  6. Hydrothermal alteration of kimberlite by convective flows of external water.

    PubMed

    Afanasyev, A A; Melnik, O; Porritt, L; Schumacher, J C; Sparks, R S J

    Kimberlite volcanism involves the emplacement of olivine-rich volcaniclastic deposits into volcanic vents or pipes. Kimberlite deposits are typically pervasively serpentinised as a result of the reaction of olivine and water within a temperature range of 130-400 °C or less. We present a model for the influx of ground water into hot kimberlite deposits coupled with progressive cooling and serpentisation. Large-pressure gradients cause influx and heating of water within the pipe with horizontal convergent flow in the host rock and along pipe margins, and upward flow within the pipe centre. Complete serpentisation is predicted for wide ranges of permeability of the host rocks and kimberlite deposits. For typical pipe dimensions, cooling times are centuries to a few millennia. Excess volume of serpentine results in filling of pore spaces, eventually inhibiting fluid flow. Fresh olivine is preserved in lithofacies with initial low porosity, and at the base of the pipe where deeper-level host rocks have low permeability, and the pipe is narrower leading to faster cooling. These predictions are consistent with fresh olivine and serpentine distribution in the Diavik A418 kimberlite pipe, (NWT, Canada) and with features of kimberlites of the Yakutian province in Russia affected by influx of ground water brines. Fast reactions and increases in the volume of solid products compared to the reactants result in self-sealing and low water-rock ratios (estimated at <0.2). Such low water-rock ratios result in only small changes in stable isotope compositions; for example, δO 18 is predicted only to change slightly from mantle values. The model supports alteration of kimberlites predominantly by interactions with external non-magmatic fluids.

  7. Anti-air pollution & energy conservation system for automobiles using leaded or unleaded gasoline, diesel or alternate fuel

    DOEpatents

    Bose, Ranendra K.

    2002-06-04

    Exhaust gases from an internal combustion engine operating with leaded or unleaded gasoline or diesel or natural gas, are used for energizing a high-speed gas turbine. The convoluting gas discharge causes a first separation stage by stratifying of heavier and lighter exhaust gas components that exit from the turbine in opposite directions, the heavier components having a second stratifying separation in a vortex tube to separate combustible pollutants from non-combustible components. The non-combustible components exit a vortex tube open end to atmosphere. The lighter combustible, pollutants effected in the first separation are bubbled through a sodium hydroxide solution for dissolving the nitric oxide, formaldehyde impurities in this gas stream before being piped to the engine air intake for re-combustion, thereby reducing the engine's exhaust pollution and improving its fuel economy. The combustible, heavier pollutants from the second separation stage are piped to air filter assemblies. This gas stream convoluting at a high-speed through the top stator-vanes of the air filters, centrifugally separates the coalescent water, aldehydes, nitrogen dioxides, sulfates, sulfur, lead particles which collect at the bottom of the bowl, wherein it is periodically released to the roadway. Whereas, the heavier hydrocarbon, carbon particles are piped through the air filter's porous element to the engine air intake for re-combustion, further reducing the engine's exhaust pollution and improving its fuel economy.

  8. Influence of biofilm formation on corrosion and scaling in geothermal plants

    NASA Astrophysics Data System (ADS)

    Kleyböcker, Anne; Lerm, Stephanie; Monika, Kasina; Tobias, Lienen; Florian, Eichinger; Andrea, Seibt; Markus, Wolfgramm; Hilke, Würdemann

    2017-04-01

    Process failures may occur due to corrosion and scaling processes in open loop geothermal systems. Especially after heat extraction, sulfate reducing bacteria (SRB) contribute to corrosion processes due to a more favorable temperature for their growth. In biofilms containing FeS scales, corrosion processes are enhanced. Furthermore, scales can lead to reduced pipe profiles, to a diminished heat transfer and a decrease in the wellbore injectivity. Inhibitors are frequently applied to minimize scaling in technical systems. A prerequisite for the application of inhibitors in geothermal plants located in the Molasse basin is their degradability under reservoir conditions, e. g. in a reduced environment. In order to determine the effects of scale-inhibitors on the subsurface and microbial processes, laboratory experiments were performed focusing on the microbial inhibitor degradation. First results indicate that the inhibitor degradation under anaerobic conditions is possible. Besides the inhibitor application also other techniques are investigated to economically reduce corrosion and scaling in geothermal plants. In a mobile bypass system, the influence of biofilm formation on corrosion and scaling was investigated. The bypass system was tested at a geothermal heat store in the North German Basin. The plant is operated with highly saline fluid (salinity 130 g/L) and known to be affected by SRB. The SRB contributed to corrosion damages especially at the pump in the well on the cold side. Heat shocks were successfully used in the bypass system to reduce biofilm formation as well as corrosion and scaling processes.

  9. A regression model for the temporal development of soil pipes and associated gullies in the alluvial-fill valley of the Rio Puerco, central New Mexico

    NASA Technical Reports Server (NTRS)

    Condit, C. D.; Elston, W. E.

    1984-01-01

    On Mars, the association of gullied escarpments and chaotic terrain is evidence for failure and scarp retreat of poorly consolidated materials. Some martian gullies have no surface outlets and may have drained through subterranean channels. Similar features, though on a much smaller scale, can be seen in alluvium along terrestrial river banks in semiarid regions, such as the Rio Puerco Valley of central New Mexico. Many of the escarpments along the Rio Puerco are developing through formation of collapse gullies, which drain through soil pipes. Gully development can be monitored on aerial photographs taken in 1935, 1962, and 1980. A regression model was developed to quantify gully evolution over a known time span. Soil pipes and their associated collapse gullies make recognizable signatures on the air photos. The areal extent of this signature can be normalized to the scarp length of each pipe-gully system, which makes comparisons between systems possible.

  10. Economic optimization of the energy transport component of a large distributed solar power plant

    NASA Technical Reports Server (NTRS)

    Turner, R. H.

    1976-01-01

    A solar thermal power plant with a field of collectors, each locally heating some transport fluid, requires a pipe network system for eventual delivery of energy power generation equipment. For a given collector distribution and pipe network geometry, a technique is herein developed which manipulates basic cost information and physical data in order to design an energy transport system consistent with minimized cost constrained by a calculated technical performance. For a given transport fluid and collector conditions, the method determines the network pipe diameter and pipe thickness distribution and also insulation thickness distribution associated with minimum system cost; these relative distributions are unique. Transport losses, including pump work and heat leak, are calculated operating expenses and impact the total system cost. The minimum cost system is readily selected. The technique is demonstrated on six candidate transport fluids to emphasize which parameters dominate the system cost and to provide basic decision data. Three different power plant output sizes are evaluated in each case to determine severity of diseconomy of scale.

  11. Procedure improves line pipe Charpy test interpretation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rosenfeld, M.J.

    1997-04-14

    The Charpy V-notch (CVN) impact test is a method of characterizing a line-pipe material`s notch toughness and resistance to fracture growth. Although CVN testing of line pipe material is routine, test results are sometimes misinterpreted because of specimen size and load rate on actual toughness transition behavior. These effects are readily accounted for by a simple mathematical procedure, offered here, which enables extrapolation of the full-scale transition curve from as little as a single subsize specimen test. This procedure is useful when the toughness transition curve is incomplete or nonexistent. Toughness data may be incomplete because the API 5L toughnessmore » test establishes minimum performance at a single temperature, which does not reveal the full transition curve. Toughness data may be nonexistent because the first requirements for toughness testing of line pipe appeared in the 16th Edition of API 5LX in 1969, and those requirements remain at the option of the purchaser today.« less

  12. High Temperature Properties Test and Research of 9Cr1Mo (P9) Seamless Pipe Used in Petrochemical Industry

    NASA Astrophysics Data System (ADS)

    Wang, Qijiang; Zhou, Yedong; Zhang, Qinglian

    Production technical process of BaoSteel-produced 9Cr1Mo (P9) seamless pipe is presented, and creep property of isothermal annealed state of that steel is studied under the temperatures of 550 °C, 600 °C, 650 °C, 700 °C. Also, isothermal extrapolation method and Larson-Miller method are employed to extrapolate creep rupture strength of the steel at the creep time of 20000h, 40000h, 60000h and 100000h. The results show that high temperature properties of BaoSteel-produced 9Cr1Mo (P9) seamless pipe meets the API 530 standard of USA and the SH/T3037 standard of China's petrochemical industry, and the steel can be used in large scale petroleum cracking equipment. Meantime, the comparison of creep properties at 650 °C and transient elevated temperature properties at different temperatures between isothermal annealed state and normalized + tempered state of 9Cr1Mo (P9) seamless pipe as well as the microstructure analysis show that the normalized + tempered 9Cr1Mo (P9) seamless pipe presents better high temperature properties.

  13. Design of megawatt power level heat pipe reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mcclure, Patrick Ray; Poston, David Irvin; Dasari, Venkateswara Rao

    An important niche for nuclear energy is the need for power at remote locations removed from a reliable electrical grid. Nuclear energy has potential applications at strategic defense locations, theaters of battle, remote communities, and emergency locations. With proper safeguards, a 1 to 10-MWe (megawatt electric) mobile reactor system could provide robust, self-contained, and long-term power in any environment. Heat pipe-cooled fast-spectrum nuclear reactors have been identified as a candidate for these applications. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than “traditional” reactors.more » The goal of this project was to develop a scalable conceptual design for a compact reactor and to identify scaling issues for compact heat pipe cooled reactors in general. Toward this goal two detailed concepts were developed, the first concept with more conventional materials and a power of about 2 MWe and a the second concept with less conventional materials and a power level of about 5 MWe. A series of more qualitative advanced designs were developed (with less detail) that show power levels can be pushed to approximately 30 MWe.« less

  14. Visualization of Flow in Pressurizer Spray Line Piping and Estimation of Thermal Stress Fluctuation Caused by Swaying of Water Surface

    NASA Astrophysics Data System (ADS)

    Oumaya, Toru; Nakamura, Akira; Onojima, Daisuke; Takenaka, Nobuyuki

    The pressurizer spray line of PWR plants cools reactor coolant by injecting water into pressurizer. Since the continuous spray flow rate during commercial operation of the plant is considered insufficient to fill the pipe completely, there is a concern that a water surface exists in the pipe and may periodically sway. In order to identify the flow regimes in spray line piping and assess their impact on pipe structure, a flow visualization experiment was conducted. In the experiment, air was used substituted for steam to simulate the gas phase of the pressurizer, and the flow instability causing swaying without condensation was investigated. With a full-scale mock-up made of acrylic, flow under room temperature and atmospheric pressure conditions was visualized, and possible flow regimes were identified based on the results of the experiment. Three representative patterns of swaying of water surface were assumed, and the range of thermal stress fluctuation, when the surface swayed instantaneously, was calculated. With the three patterns of swaying assumed based on the visualization experiment, it was confirmed that the thermal stress amplitude would not exceed the fatigue endurance limit prescribed in the Japanese Design and Construction Code.

  15. Effects of Sulfate, Chloride, and Bicarbonate on Iron Stability in a PVC-U Drinking Pipe

    PubMed Central

    Wang, Jiaying; Tao, Tao; Yan, Hexiang

    2017-01-01

    In order to describe iron stability in plastic pipes and to ensure the drinking water security, the influence factors and rules for iron adsorption and release were studied, dependent on the Unplasticized poly (vinyl chloride) (PVC-U) drinking pipes employed in this research. In this paper, sulfate, chloride, and bicarbonate, as well as synthesized models, were chosen to investigate the iron stability on the inner wall of PVC-U drinking pipes. The existence of the three kinds of anions could significantly affect the process of iron adsorption, and a positive association was found between the level of anion concentration and the adsorption rate. However, the scaling formed on the inner surface of the pipes would be released into the water under certain conditions. The Larson Index (LI), used for a synthetic consideration of anion effects on iron stability, was selected to investigate the iron release under multi-factor conditions. Moreover, a well fitted linear model was established to gain a better understanding of iron release under multi-factor conditions. The simulation results demonstrated that the linear model was better fitted than the LI model for the prediction of iron release. PMID:28629192

  16. Granular Materials and the Risks They Pose for Success on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Wilkinson, R. Allen; Behringer, Robert P.; Jenkins, James T.; Louge, Michel Y.

    2004-01-01

    Working with soil, sand, powders, ores, cement and sintered bricks, excavating, grading construction sites, driving off-road, transporting granules in chutes and pipes, sifting gravel, separating solids from gases, and using hoppers are so routine that it seems straightforward to do it on the Moon and Mars as we do it on Earth. This paper brings to the fore how little these processes are understood and the millennia-long trial-and-error practices that lead to today's massive over-design, high failure rate, and extensive incremental scaling up of industrial processes because of the inadequate predictive tools for design. We present a number of pragmatic scenarios where granular materials play a role, the risks involved, and what understanding is needed to greatly reduce the risks.

  17. Granular Materials and the Risks They Pose for Success on the Moon and Mars

    NASA Astrophysics Data System (ADS)

    Wilkinson, R. Allen; Behringer, Robert P.; Jenkins, James T.; Louge, Michel Y.

    2005-02-01

    Working with soil, sand, powders, ores, cement and sintered bricks, excavating, grading construction sites, driving off-road, transporting granules in chutes and pipes, sifting gravel, separating solids from gases, and using hoppers are so routine that it seems straightforward to do it on the Moon and Mars as we do it on Earth. This paper brings to the fore how little these processes are understood and the millennia-long trial-and-error practices that lead to today's massive over-design, high failure rate, and extensive incremental scaling up of industrial processes because of the inadequate predictive tools for design. We present a number of pragmatic scenarios where granular materials play a role, the risks involved, and what understanding is needed to greatly reduce the risks.

  18. Method for Determination of Less Than 5 ppm Oxygen in Sodium Samples

    NASA Technical Reports Server (NTRS)

    Reid, R. S.; Martin, J. J.; Schmidt, G. L.

    2005-01-01

    Alkali metals used in pumped loops or heat pipes must be sufficiently free of nonmetallic impurities to ensure long heat rejection system life. Life issues are well established for alkali metal systems. Impurities can form ternary compounds between the container and working fluid, leading to corrosion. This Technical Memorandum discusses the consequences of impurities and candidate measurement techniques to determine whether impurities have been reduced to suf.ciently low levels within a single-phase liquid metal loop or a closed two-phase heat transfer system, such as a heat pipe. These techniques include the vanadium wire equilibration, neutron activation analysis, plug traps, distillation, and chemical analysis. Conceptual procedures for performing vanadium wire equilibration purity measurements on sodium contained in a heat pipe are discussed in detail.

  19. Assessment of domestic water quality: case study, Beirut, Lebanon.

    PubMed

    Korfali, Samira Ibrahim; Jurdi, Mey

    2007-12-01

    In urban cities, the environmental services are the responsibility of the public sector, where piped water supply is the norm for urban household. Likewise, in Beirut City (capital of Lebanon) official water authorities are the main supplier of domestic water through a network of piping system that leaks in many areas. Beirut City and its suburbs are overpopulated since it is the residence of 1/3 of the Lebanese citizens. Thus, Beirut suffers deficiency in meeting its water demand. Water rationing, as a remedial action, is firmly established since four decades by the Lebanese Water Authorities. Consumers resorted then to private wells to supplement their domestic water needs. Consequently, household water quality is influenced by external factors relating to well water characteristics and internal factors depending on the types of the pipes of the distribution network and cross connections to sewer pipes. These factors could result in chemical and microbial contamination of drinking water. The objective of this study is to investigate domestic water quality variation in Beirut City emerging form the aforementioned factors. The presented work encircles a typical case study of Beirut City (Ras Beirut). Results showed deterioration pattern in domestic water quality. The predicted metal species and scales within the water pipes of distribution network depended on water pH, hardness, sulfate, chloride, and iron. The corrosion of iron pipes mainly depended on Mg hardness.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Swamy, S.A.; Mandava, P.R.; Bhowmick, D.C.

    The leak-before-break (LBB) methodology is accepted as a technically justifiable approach for eliminating postulation of Double-Ended Guillotine Breaks (DEGB) in high energy piping systems. This is the result of extensive research, development, and rigorous evaluations by the NRC and the commercial nuclear power industry since the early 1970s. The DEGB postulation is responsible for the many hundreds of pipe whip restraints and jet shields found in commercial nuclear plants. These restraints and jet shields not only cost many millions of dollars, but also cause plant congestion leading to reduced reliability in inservice inspection and increased man-rem exposure. While use ofmore » leak-before-break technology saved hundreds of millions of dollars in backfit costs to many operating Westinghouse plants, value-impacts resulting from the application of this technology for future plants are greater on a per plant basis. These benefits will be highlighted in this paper. The LBB technology has been applied extensively to high energy piping systems in operating plants. However, there are differences between the application of LBB technology to an operating plant and to a new plant design. In this paper an approach is proposed which is suitable for application of LBB to a new plant design such as the Westinghouse AP600. The approach is based on generating Bounding Analyses Curves (BAC) for the candidate piping systems. The general methodology and criteria used for developing the BACs are based on modified GDC-4 and Standard Review Plan (SRP) 3.6.3. The BAC allows advance evaluation of the piping system from the LBB standpoint thereby assuring LBB conformance for the piping system. The piping designer can use the results of the BACs to determine acceptability of design loads and make modifications (in terms of piping layout and support configurations) as necessary at the design stage to assure LBB for the, piping systems under consideration.« less

  1. Experimental testing and modeling analysis of solute mixing at water distribution pipe junctions.

    PubMed

    Shao, Yu; Jeffrey Yang, Y; Jiang, Lijie; Yu, Tingchao; Shen, Cheng

    2014-06-01

    Flow dynamics at a pipe junction controls particle trajectories, solute mixing and concentrations in downstream pipes. The effect can lead to different outcomes of water quality modeling and, hence, drinking water management in a distribution network. Here we have investigated solute mixing behavior in pipe junctions of five hydraulic types, for which flow distribution factors and analytical equations for network modeling are proposed. First, based on experiments, the degree of mixing at a cross is found to be a function of flow momentum ratio that defines a junction flow distribution pattern and the degree of departure from complete mixing. Corresponding analytical solutions are also validated using computational-fluid-dynamics (CFD) simulations. Second, the analytical mixing model is further extended to double-Tee junctions. Correspondingly the flow distribution factor is modified to account for hydraulic departure from a cross configuration. For a double-Tee(A) junction, CFD simulations show that the solute mixing depends on flow momentum ratio and connection pipe length, whereas the mixing at double-Tee(B) is well represented by two independent single-Tee junctions with a potential water stagnation zone in between. Notably, double-Tee junctions differ significantly from a cross in solute mixing and transport. However, it is noted that these pipe connections are widely, but incorrectly, simplified as cross junctions of assumed complete solute mixing in network skeletonization and water quality modeling. For the studied pipe junction types, analytical solutions are proposed to characterize the incomplete mixing and hence may allow better water quality simulation in a distribution network. Published by Elsevier Ltd.

  2. 30 CFR 18.38 - Leads through common walls.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design... from one explosion-proof enclosure to another through conduit, tubing, piping, or other solid-wall...

  3. 30 CFR 18.38 - Leads through common walls.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design... from one explosion-proof enclosure to another through conduit, tubing, piping, or other solid-wall...

  4. 30 CFR 18.38 - Leads through common walls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design... from one explosion-proof enclosure to another through conduit, tubing, piping, or other solid-wall...

  5. 30 CFR 18.38 - Leads through common walls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design... from one explosion-proof enclosure to another through conduit, tubing, piping, or other solid-wall...

  6. A new mechanism for periodic bursting of the recirculation region in the flow through a sudden expansion in a circular pipe

    NASA Astrophysics Data System (ADS)

    Lebon, Benoit; Nguyen, Minh Quan; Peixinho, Jorge; Shadloo, Mostafa Safdari; Hadjadj, Abdellah

    2018-03-01

    We report the results of a combined experimental and numerical study of specific finite-amplitude disturbances for transition to turbulence in the flow through a circular pipe with a sudden expansion. The critical amplitude thresholds for localized turbulent patch downstream of the expansion scale with the Reynolds number with a power law exponent of -2.3 for experiments and -2.8 for simulations. A new mechanism for the periodic bursting of the recirculation region is uncovered where the asymmetric recirculation flow develops a periodic dynamics: a secondary recirculation breaks the symmetry along the pipe wall and bursts into localized turbulence, which travels downstream and relaminarises. Flow visualizations show a simple flow pattern of three waves forming, growing, and bursting.

  7. On the nonlinear stability of the unsteady, viscous flow of an incompressible fluid in a curved pipe

    NASA Technical Reports Server (NTRS)

    Shortis, Trudi A.; Hall, Philip

    1995-01-01

    The stability of the flow of an incompressible, viscous fluid through a pipe of circular cross-section curved about a central axis is investigated in a weakly nonlinear regime. A sinusoidal pressure gradient with zero mean is imposed, acting along the pipe. A WKBJ perturbation solution is constructed, taking into account the need for an inner solution in the vicinity of the outer bend, which is obtained by identifying the saddle point of the Taylor number in the complex plane of the cross-sectional angle co-ordinate. The equation governing the nonlinear evolution of the leading order vortex amplitude is thus determined. The stability analysis of this flow to periodic disturbances leads to a partial differential system dependent on three variables, and since the differential operators in this system are periodic in time, Floquet theory may be applied to reduce this system to a coupled infinite system of ordinary differential equations, together with homogeneous uncoupled boundary conditions. The eigenvalues of this system are calculated numerically to predict a critical Taylor number consistent with the analysis of Papageorgiou. A discussion of how nonlinear effects alter the linear stability analysis is also given, and the nature of the instability determined.

  8. Foraging ecology of least terns and piping plovers nesting on Central Platte River sandpits and sandbars

    USGS Publications Warehouse

    Sherfy, Mark H.; Anteau, Michael J.; Shaffer, Terry L.; Sovada, Marsha A.; Stucker, Jennifer H.

    2012-01-01

    Federally listed least terns (Sternula antillarum) and piping plovers (Charadrius melodus) nest on riverine sandbars on many major midcontinent river systems. On the Central Platte River, availability of sandbar habitat is limited, and both species nest on excavated sandpits in the river's floodplain. However, the extent to which sandpit-nesting birds use riverine habitats for foraging is unknown. We evaluated use of foraging habitats by least terns and piping plovers by collecting data on movements, behavior, foraging habitat, and productivity. We radiomarked 16 piping plovers and 23 least terns in 2009-2010 and monitored their movements using a network of fixed telemetry dataloggers. Piping plovers were detected primarily by the datalogger located in their nesting sandpit, whereas least terns were more frequently detected on dataloggers outside of the nesting sandpit. Telemetry data and behavioral observations showed that least terns tended to concentrate at the Kearney Canal Diversion Gates, where forage fish were apparently readily available. Fish sampling data suggested that forage fish were more abundant in riverine than in sandpit habitats, and behavioral observations showed that least terns foraged more frequently in riverine than in sandpit habitats. Piping plovers tended to forage in wet substrates along sandpit shorelines, but also used dry substrates and sandpit interior habitats. The greater mobility of least terns makes a wider range of potential foraging habitats available during brood rearing, making them able to exploit concentrations of fish outside the nesting colony. Thus, our data suggest that different spatial scales should be considered in managing nesting and foraging habitat complexes for piping plovers and least terns.

  9. Investigation of guided waves propagation in pipe buried in sand

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leinov, Eli; Cawley, Peter; Lowe, Michael J.S.

    The inspection of pipelines by guided wave testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the waves caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the propagation and attenuation characteristics of guided waves in pipes buried in fine sand usingmore » a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided waves are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of wave behavior in the buried pipe. We present the methodology and the systematic measurements of the guided waves under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided waves in buried pipes with a high level of confidence.« less

  10. methylPipe and compEpiTools: a suite of R packages for the integrative analysis of epigenomics data.

    PubMed

    Kishore, Kamal; de Pretis, Stefano; Lister, Ryan; Morelli, Marco J; Bianchi, Valerio; Amati, Bruno; Ecker, Joseph R; Pelizzola, Mattia

    2015-09-29

    Numerous methods are available to profile several epigenetic marks, providing data with different genome coverage and resolution. Large epigenomic datasets are then generated, and often combined with other high-throughput data, including RNA-seq, ChIP-seq for transcription factors (TFs) binding and DNase-seq experiments. Despite the numerous computational tools covering specific steps in the analysis of large-scale epigenomics data, comprehensive software solutions for their integrative analysis are still missing. Multiple tools must be identified and combined to jointly analyze histone marks, TFs binding and other -omics data together with DNA methylation data, complicating the analysis of these data and their integration with publicly available datasets. To overcome the burden of integrating various data types with multiple tools, we developed two companion R/Bioconductor packages. The former, methylPipe, is tailored to the analysis of high- or low-resolution DNA methylomes in several species, accommodating (hydroxy-)methyl-cytosines in both CpG and non-CpG sequence context. The analysis of multiple whole-genome bisulfite sequencing experiments is supported, while maintaining the ability of integrating targeted genomic data. The latter, compEpiTools, seamlessly incorporates the results obtained with methylPipe and supports their integration with other epigenomics data. It provides a number of methods to score these data in regions of interest, leading to the identification of enhancers, lncRNAs, and RNAPII stalling/elongation dynamics. Moreover, it allows a fast and comprehensive annotation of the resulting genomic regions, and the association of the corresponding genes with non-redundant GeneOntology terms. Finally, the package includes a flexible method based on heatmaps for the integration of various data types, combining annotation tracks with continuous or categorical data tracks. methylPipe and compEpiTools provide a comprehensive Bioconductor-compliant solution for the integrative analysis of heterogeneous epigenomics data. These packages are instrumental in providing biologists with minimal R skills a complete toolkit facilitating the analysis of their own data, or in accelerating the analyses performed by more experienced bioinformaticians.

  11. Experimental investigation of the flow dynamics and rheology of complex fluids in pipe flow by hybrid multi-scale velocimetry

    NASA Astrophysics Data System (ADS)

    Haavisto, Sanna; Cardona, Maria J.; Salmela, Juha; Powell, Robert L.; McCarthy, Michael J.; Kataja, Markku; Koponen, Antti I.

    2017-11-01

    A hybrid multi-scale velocimetry method utilizing Doppler optical coherence tomography in combination with either magnetic resonance imaging or ultrasound velocity profiling is used to investigate pipe flow of four rheologically different working fluids under varying flow regimes. These fluids include water, an aqueous xanthan gum solution, a softwood fiber suspension, and a microfibrillated cellulose suspension. The measurement setup enables not only the analysis of the rheological (bulk) behavior of a studied fluid but gives simultaneously information on their wall layer dynamics, both of which are needed for analyzing and solving practical fluid flow-related problems. Preliminary novel results on rheological and boundary layer flow properties of the working fluids are reported and the potential of the hybrid measurement setup is demonstrated.

  12. Ulcerative Colitis: Are We Neglecting Its Progressive Character.

    PubMed

    Massinha, Paulo; Portela, Francisco; Campos, Sara; Duque, Gabriela; Ferreira, Manuela; Mendes, Sofia; Ferreira, Ana Margarida; Sofia, Carlos; Tomé, Luís

    2018-03-01

    Ulcerative colitis (UC) is a chronic disease but its progressive character, with structural damage, is insufficiently studied. To analyze a group of patients without referral bias, regarding its clinical course, the morphological damage, and functional status. We evaluated UC patients diagnosed between January 1, 2000 and December 31, 2004, living in the direct referral area of the hospital and determined the medication use, colectomy rate, structural damage ("lead pipe," stenosis, pseudopolyps, fibrous bridges), and anorectal function (prospective evaluation with the Cleveland Clinic Incontinence Score [CCIS] and the Fecal Incontinence Quality of Life Scale). We identified 104 patients, 47% female, with a mean age at diagnosis of 38 ± 17 years, 24% with proctitis, 57% with left colitis, and 19% with pancolitis. In 3 patients, it was not possible to obtain follow-up data. Of the studied patients, 56% needed corticosteroid therapy, 38% immunosuppressants, and 16% anti-tumor necrosis factors (anti-TNFs). After a mean follow-up of 13 ± 2 years, we found structural damage in 25 patients (24%): 5% with proctocolectomy, 15% with "lead pipe," 16% with pseudopolyps, and 3% with stenosis and fibrous bridges. Reference to functional anorectal disorders was identified in 49%, mostly previous and self-limited episodes of incontinence, but including persistent incontinence in 10% (CCIS 8 ± 4.8). There was an increased incidence of structural damage and anorectal dysfunction in patients who needed corticosteroid therapy ( p = 0.001), immunosuppressants ( p < 0.001), and anti-TNFs ( p = 0.002) and an association of structural damage with anorectal dysfunction ( p < 0.001). There was no association between age and anorectal dysfunction, including incontinence episodes. UC is a disease with structural and functional consequences in a significant subset of patients. This should be incorporated when defining the therapeutic strategy.

  13. Ulcerative Colitis: Are We Neglecting Its Progressive Character

    PubMed Central

    Massinha, Paulo; Portela, Francisco; Campos, Sara; Duque, Gabriela; Ferreira, Manuela; Mendes, Sofia; Ferreira, Ana Margarida; Sofia, Carlos; Tomé, Luís

    2018-01-01

    Introduction Ulcerative colitis (UC) is a chronic disease but its progressive character, with structural damage, is insufficiently studied. Objectives To analyze a group of patients without referral bias, regarding its clinical course, the morphological damage, and functional status. Methods We evaluated UC patients diagnosed between January 1, 2000 and December 31, 2004, living in the direct referral area of the hospital and determined the medication use, colectomy rate, structural damage (“lead pipe,” stenosis, pseudopolyps, fibrous bridges), and anorectal function (prospective evaluation with the Cleveland Clinic Incontinence Score [CCIS] and the Fecal Incontinence Quality of Life Scale). Results We identified 104 patients, 47% female, with a mean age at diagnosis of 38 ± 17 years, 24% with proctitis, 57% with left colitis, and 19% with pancolitis. In 3 patients, it was not possible to obtain follow-up data. Of the studied patients, 56% needed corticosteroid therapy, 38% immunosuppressants, and 16% anti-tumor necrosis factors (anti-TNFs). After a mean follow-up of 13 ± 2 years, we found structural damage in 25 patients (24%): 5% with proctocolectomy, 15% with “lead pipe,” 16% with pseudopolyps, and 3% with stenosis and fibrous bridges. Reference to functional anorectal disorders was identified in 49%, mostly previous and self-limited episodes of incontinence, but including persistent incontinence in 10% (CCIS 8 ± 4.8). There was an increased incidence of structural damage and anorectal dysfunction in patients who needed corticosteroid therapy (p = 0.001), immunosuppressants (p < 0.001), and anti-TNFs (p = 0.002) and an association of structural damage with anorectal dysfunction (p < 0.001). There was no association between age and anorectal dysfunction, including incontinence episodes. Conclusions UC is a disease with structural and functional consequences in a significant subset of patients. This should be incorporated when defining the therapeutic strategy. PMID:29662931

  14. Stormwater infiltration and the 'urban karst' - A review

    NASA Astrophysics Data System (ADS)

    Bonneau, Jeremie; Fletcher, Tim D.; Costelloe, Justin F.; Burns, Matthew J.

    2017-09-01

    The covering of native soils with impervious surfaces (e.g. roofs, roads, and pavement) prevents infiltration of rainfall into the ground, resulting in increased surface runoff and decreased groundwater recharge. When this excess water is managed using stormwater drainage systems, flow and water quality regimes of urban streams are severely altered, leading to the degradation of their ecosystems. Urban streams restoration requires alternative approaches towards stormwater management, which aim to restore the flow regime towards pre-development conditions. The practice of stormwater infiltration-achieved using a range of stormwater source-control measures (SCMs)-is central to restoring baseflow. Despite this, little is known about what happens to the infiltrated water. Current knowledge about the impact of stormwater infiltration on flow regimes was reviewed. Infiltration systems were found to be efficient at attenuating high-flow hydrology (reducing peak magnitudes and frequencies) at a range of scales (parcel, streetscape, catchment). Several modelling studies predict a positive impact of stormwater infiltration on baseflow, and empirical evidence is emerging, but the fate of infiltrated stormwater remains unclear. It is not known how infiltrated water travels along the subsurface pathways that characterise the urban environment, in particular the 'urban karst', which results from networks of human-made subsurface pathways, e.g. stormwater and sanitary sewer pipes and associated high permeability trenches. Seepage of groundwater into and around such pipes is possible, meaning some infiltrated stormwater could travel along artificial pathways. The catchment-scale ability of infiltration systems to restore groundwater recharge and baseflow is thus ambiguous. Further understanding of the fate of infiltrated stormwater is required to ensure infiltration systems deliver optimal outcomes for waterway flow regimes.

  15. Characterization of a carbon fiber reinforced polymer repair system for structurally deficient steel piping

    NASA Astrophysics Data System (ADS)

    Wilson, Jeffrey M.

    This Dissertation investigates a carbon fiber reinforced polymer repair system for structurally deficient steel piping. Numerous techniques exist for the repair of high-pressure steel piping. One repair technology that is widely gaining acceptance is composite over-wraps. Thermal analytical evaluations of the epoxy matrix material produced glass transition temperature results, a cure kinetic model, and a workability chart. These results indicate a maximum glass transition temperature of 80°C (176°F) when cured in ambient conditions. Post-curing the epoxy, however, resulted in higher glass-transition temperatures. The accuracy of cure kinetic model presented is temperature dependent; its accuracy improves with increased cure temperatures. Cathodic disbondment evaluations of the composite over-wrap show the epoxy does not breakdown when subjected to a constant voltage of -1.5V and the epoxy does not allow corrosion to form under the wrap from permeation. Combustion analysis of the composite over-wrap system revealed the epoxy is flammable when in direct contact with fire. To prevent combustion, an intumescent coating was developed to be applied on the composite over-wrap. Results indicate that damaged pipes repaired with the carbon fiber composite over-wrap withstand substantially higher static pressures and exhibit better fatigue characteristics than pipes lacking repair. For loss up to 80 percent of the original pipe wall thickness, the composite over-wrap achieved failure pressures above the pipe's specified minimum yield stress during monotonic evaluations and reached the pipe's practical fatigue limit during cyclical pressure testing. Numerous repairs were made to circular, thru-wall defects and monotonic pressure tests revealed containment up to the pipe's specified minimum yield strength for small diameter defects. The energy release rate of the composite over-wrap/steel interface was obtained from these full-scale, leaking pipe evaluations and results indicate a large amount of scatter is associated with this test method. Due to the large amount of scatter present in the leaking pipe evaluations (energy release rate tests), a new laboratory specimen was created to evaluate mixed mode debonding of composite over-wrapped piping. The laboratory specimen results are much more conservative than the leaking pipe evaluations. The laboratory specimen results, however, agree quite favorably to a closed form solution developed in this Dissertation, as well as to energy release rate calculations performed by two different finite element analysis methods, the Modified Crack Closure Integral and the change in compliance method.

  16. 46. Photocopy of scale drawing (from Station 'L' office files, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. Photocopy of scale drawing (from Station 'L' office files, Portland, Oregon) Portland General Electric in house drawing, 1937 PIPING ARRANGEMENT OF BOILER #16 BUILDING LB SHOWN IN ELEVATION (LEFT), PLAN (TOP RIGHT) AND ELEVATION (BOTTOM RIGHT) - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  17. 41. Photocopy of scale drawing (from Station 'L' office files, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. Photocopy of scale drawing (from Station 'L' office files, Portland, Oregon) Portland General Electric in house drawing, 6/28/1928 PLAN (TOP) AND ELEVATION (BOTTOM) OF BOILER #13 BUILDING L4, GENERAL LAYOUT OF THE STEAM PIPING SYSTEM - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  18. Turbulence as a Problem in Non-equilibrium Statistical Mechanics

    NASA Astrophysics Data System (ADS)

    Goldenfeld, Nigel; Shih, Hong-Yan

    2017-05-01

    The transitional and well-developed regimes of turbulent shear flows exhibit a variety of remarkable scaling laws that are only now beginning to be systematically studied and understood. In the first part of this article, we summarize recent progress in understanding the friction factor of turbulent flows in rough pipes and quasi-two-dimensional soap films, showing how the data obey a two-parameter scaling law known as roughness-induced criticality, and exhibit power-law scaling of friction factor with Reynolds number that depends on the precise form of the nature of the turbulent cascade. These results hint at a non-equilibrium fluctuation-dissipation relation that applies to turbulent flows. The second part of this article concerns the lifetime statistics in smooth pipes around the transition, showing how the remarkable super-exponential scaling with Reynolds number reflects deep connections between large deviation theory, extreme value statistics, directed percolation and the onset of coexistence in predator-prey ecosystems. Both these phenomena reflect the way in which turbulence can be fruitfully approached as a problem in non-equilibrium statistical mechanics.

  19. 46 CFR 72.20-50 - Heating and cooling.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... operating conditions without curtailing ventilation. (c) Radiators and other heating apparatus must be so... leading to radiators or heating apparatus must be insulated where those pipes create a hazard to persons...

  20. Guided wave propagation in single and double layer hollow cylinders embedded in infinite media.

    PubMed

    Jia, Hua; Jing, Mu; Joseph, L Rose

    2011-02-01

    Millions of miles of pipes are being used for the transportation, distribution, and local use of petroleum products, gas, water, and chemicals. Most of the pipes are buried in soil, leading to the significance of the study on the subject of guided wave propagation in pipes with soil influence. Previous investigations of ultrasonic guided wave propagation in an elastic hollow cylinder and in an elastic hollow cylinder coated with a viscoelastic material have led to the development of inspection techniques for bare and coated pipes. However, the lack of investigation on guided wave propagation in hollow cylinders embedded in infinite media like soil has hindered the development of pipe inspection methods. Therefore the influence of infinite media on wave propagation is explored in this paper. Dispersion curves and wave structures of both axisymmetric and nonaxisymmetric wave modes are developed. Due to the importance of the convergence of numerical calculations, the requirements of thickness and element number of the finite soil layer between hollow cylinder and infinite element layer are discussed, and an optimal combination is obtained in this paper. Wave structures are used for the mode identification in the non-monotonic region caused by the viscoelastic properties of coating and infinite media.

  1. Monitoring underground water leakage pattern by ground penetrating radar (GPR) using 800 MHz antenna frequency

    NASA Astrophysics Data System (ADS)

    Amran, T. S. T.; Ismail, M. P.; Ahmad, M. R.; Amin, M. S. M.; Ismail, M. A.; Sani, S.; Masenwat, N. A.; Basri, N. S. M.

    2018-01-01

    Water is the most treasure natural resources, however, a huge amount of water are lost during its distribution that leads to water leakage problem. The leaks meant the waste of money and created more economic loss to treat and fix the damaged pipe. Researchers and engineers have put tremendous attempts and effort, to solve the water leakage problem especially in water leakage of buried pipeline. An advanced technology of ground penetrating radar (GPR) has been established as one of the non-destructive testing (NDT) method to detect the underground water pipe leaking. This paper focuses on the ability of GPR in water utility field especially on detection of water leaks in the underground pipeline distribution. A series of laboratory experiments were carried out using 800-MHz antenna, where the performance of GPR on detecting underground pipeline and locating water leakage was investigated and validated. A prototype to recreate water-leaking system was constructed using a 4-inch PVC pipe. Different diameter of holes, i.e. ¼ inch, ½ inch, and ¾ inch, were drilled into the pipe to simulate the water leaking. The PVC pipe was buried at the depth of 60 cm into the test bed that was filled with dry sand. 15 litres of water was injected into the PVC pipe. The water leakage patterns in term of radargram data were gathered. The effectiveness of the GPR in locating the underground water leakage was ascertained, after the results were collected and verified.

  2. Sustainable urban water systems in rich and poor cities--steps towards a new approach.

    PubMed

    Newman, P

    2001-01-01

    The 'big pipes in, big pipes out' approach to urban water management was developed in the 19th century for a particular linear urban form. Large, sprawling car-dependent cities are pushing this approach to new limits in rich cities and it has never worked in poor cities. An alternative which uses new small-scale technology and is more community-based, is suggested for both rich and poor countries. The Sydney Olympics and a demonstration project in Java show that the approach can work.

  3. Computation of turbulent pipe and duct flow using third order upwind scheme

    NASA Technical Reports Server (NTRS)

    Kawamura, T.

    1986-01-01

    The fully developed turbulence in a circular pipe and in a square duct is simulated directly without using turbulence models in the Navier-Stokes equations. The utilized method employs a third-order upwind scheme for the approximation to the nonlinear term and the second-order Adams-Bashforth method for the time derivative in the Navier-Stokes equation. The computational results appear to capture the large-scale turbulent structures at least qualitatively. The significance of the artificial viscosity inherent in the present scheme is discussed.

  4. Drinking Water Contamination Due To Lead-based Solder

    NASA Astrophysics Data System (ADS)

    Garcia, N.; Bartelt, E.; Cuff, K. E.

    2004-12-01

    The presence of lead in drinking water creates many health hazards. Exposure to lead-contaminated water can affect the brain, the central nervous system, blood cells, and kidneys, causing such problems as mental retardation, kidney disease, heart disease, stroke, and death. One way in which lead can contaminate our water supply is through the use of lead solder to join pipes. Lead solder was widely used in the past because of its ease of application as well as its low cost. Lead contamination in residential areas has previously been found to be a particularly serious problem in first-draw samples, of water that has sat stagnant in pipes overnight. To investigate the time-dependence of drinking water lead contamination, we analyzed samples taken hourly of water exposed to lead solder. While our preliminary data was insufficient to show more than a rough correlation between time of exposure and lead concentration over short periods (1-3 hours), we were able to confirm that overnight exposure of water to lead-based solder results in the presence high levels of lead. We also investigated other, external factors that previous research has indicated contribute to increased concentrations of lead. Our analysis of samples of lead-exposed water at various pH and temperatures suggests that these factors can be equally significant in terms of their contribution to elevated lead concentration levels. In particular, water that is slightly corrosive appears to severely impact the solubility of lead. As this type of water is common in much of the Northeast United States, the presence of lead-based solder in residential areas there is especially problematic. Although lead-based solder has been banned since the 1980s, it remains a serious concern, and a practical solution still requires further research.

  5. CaSO4 Scale Inhibition by a Trace Amount of Zinc Ion in Piping System

    NASA Astrophysics Data System (ADS)

    Mangestiyono, W.; Sutrisno

    2017-05-01

    Usually, a small steam generator is not complemented by equipment such as demineralization and chlorination process apparatus since the economic aspect was a precedence. Such phenomenon was uncovered in a case study of green tea industrial process in which the boiler capacity was not more than 1 ton/hour. The operation of the small boiler affected the scaling process in its piping system. In a year operation, there was already a large scale of calcium attached to the inner surface of the pipe. Such large scale formed a layer and decreased the overall heat transfer coefficient, prolonged the process time and decreased the production. The aim of the current research was to solve the problem through a laboratory research to inhibit the CaSO4 scale formation by the addition of trace amounts of zinc ion. This research was conducted through a built in-house experimental rig which consisted of a dosing pump for controlling the flow rate and a thermocouple to control the temperature. Synthesis solution was prepared with 3,500 ppm concentration of CaCl2 and Na2SO4. The concentration of zinc was set at 0.00; 5.00 and 10.00 ppm. The data found were characterized by scanning electron microscopy (SEM) to analyze crystal polymorph as the influence of zinc ion addition. The induction time was also investigated to analyze the nucleation time, and it was found on the 9th, 13th, and 19th minute of the zinc ion addition of 0.00, 5.00 and 10.00 ppm. After running for a four-hour duration, the scale grow-rate was found to be 5.799; 5.501 and 4.950 × 10-3 gr/min for 0.00; 5.00 and 10.00 ppm of zinc addition at 50 °C.

  6. Trials of flexible pipe in sour service reveal degradation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Maslamani, M.J.

    Field trials on flexible pipe offshore Qatar have shown that, under sour conditions, the layered, composite material can suffer severe degradation leading to failure. The failure demonstrates the significant effects of stress level, environmental aggressiveness, and localized hard zones in promoting sulfide stress cracking. Permeability of the sour gas through the composite layer of the flexible pipe resulted in varying degrees of sulfide attack and hydrogen embrittlement, depending on the susceptibility of the multilayered material. In the trials, the material was used as a gas-lift line in a sour-oil field in the Arabian Gulf. Flexible pipes have been used successfullymore » for transporting methanol, benzene, and gas condensates in wet sweet environments at temperatures of up to 80 C. Little or no information, however, has been available as to its corrosion resistance in sour-service wells containing 6% CO{sub 2} with 3% H{sub 2}S partial pressures and at moderate temperatures. The paper discusses an underwater survey to evaluate the damage, visual inspection, mechanical tests, metallographic exam, and trial results.« less

  7. Numerical Investigation of Temperature Distribution in an Eroded Bend Pipe and Prediction of Erosion Reduced Thickness

    PubMed Central

    Zhu, Hongjun; Feng, Guang; Wang, Qijun

    2014-01-01

    Accurate prediction of erosion thickness is essential for pipe engineering. The objective of the present paper is to study the temperature distribution in an eroded bend pipe and find a new method to predict the erosion reduced thickness. Computational fluid dynamic (CFD) simulations with FLUENT software are carried out to investigate the temperature field. And effects of oil inlet rate, oil inlet temperature, and erosion reduced thickness are examined. The presence of erosion pit brings about the obvious fluctuation of temperature drop along the extrados of bend. And the minimum temperature drop presents at the most severe erosion point. Small inlet temperature or large inlet velocity can lead to small temperature drop, while shallow erosion pit causes great temperature drop. The dimensionless minimum temperature drop is analyzed and the fitting formula is obtained. Using the formula we can calculate the erosion reduced thickness, which is only needed to monitor the outer surface temperature of bend pipe. This new method can provide useful guidance for pipeline monitoring and replacement. PMID:24719576

  8. 46 CFR 190.20-50 - Heating and cooling.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the space. (b) Radiators and other heating apparatus must be so placed and shielded, where necessary, to avoid risk of fire, danger or discomfort to the occupants. Pipes leading to radiators or heating...

  9. 76 FR 39104 - Science Advisory Board Staff Office; Notification of a Public Teleconference of the Chartered...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    ... concerning the EPA Science Advisory Board can be found on the EPA Web site at http://www.epa.gov/sab... SAB Staff Office procedural policies. Background: Exposure to lead through drinking water results primarily from the corrosion of lead pipes and plumbing materials. EPA's Office of Water (OW) promulgated...

  10. Formation of Si-Al-Mg-Ca-rich zoned magnetite in an end-Permian phreatomagmatic pipe in the Tunguska Basin, East Siberia

    NASA Astrophysics Data System (ADS)

    Neumann, Else-Ragnhild; Svensen, Henrik H.; Polozov, Alexander G.; Hammer, Øyvind

    2017-12-01

    Magma-sediment interactions in the evaporite-rich Tunguska Basin resulted in the formation of numerous phreatomagmatic pipes during emplacement of the Siberian Traps. The pipes contain magnetite-apatite deposits with copper and celestine mineralization. We have performed a detailed petrographic and geochemical study of magnetite from long cores drilled through three pipe breccia structures near Bratsk, East Siberia. The magnetite samples are zoned and rich in Si (≤5.3 wt% SiO2), Ca, Al, and Mg. They exhibit four textural types: (1) massive ore in veins, (2) coating on breccia clasts, (3) replacement ore, and (4) reworked ore at the crater base. The textural types have different chemical characteristics. "Breccia coating" magnetite has relatively low Mg content relative to Si, as compared to the other groups, and appears to have formed at lower oxygen fugacity. Time series analyses of MgO variations in microprobe transects across Si-bearing magnetite in massive ore indicate that oscillatory zoning in the massive ore was controlled by an internal self-organized process. We suggest that hydrothermal Fe-rich brines were supplied from basalt-sediment interaction zones in the evaporite-rich sedimentary basin, leading to magnetite ore deposition in the pipes. Hydrothermal fluid composition appears to be controlled by proximity to dolerite fragments, temperature, and oxygen fugacity. Magnetite from the pipes has attributes of iron oxide-apatite deposits (e.g., textures, oscillatory zoning, association with apatite, and high Si content) but has higher Mg and Ca content and different mineral assemblages. These features are similar to magnetite found in skarn deposits. We conclude that the Siberian Traps-related pipe magnetite deposit gives insight into the metamorphic and hydrothermal effects following magma emplacement in a sedimentary basin.

  11. Geology and geochemistry of the Mammoth breccia pipe, Copper Creek mining district, southeastern Arizona: Evidence for a magmatic-hydrothermal origin

    USGS Publications Warehouse

    Anderson, E.D.; Atkinson, William W.; Marsh, T.; Iriondo, A.

    2009-01-01

    The Copper Creek mining district, southeastern Arizona, contains more than 500 mineralized breccia pipes, buried porphyry-style, copper-bearing stockworks, and distal lead-silver veins. The breccia pipes are hosted by the Copper Creek Granodiorite and the Glory Hole volcanic rocks. The unexposed Mammoth breccia pipe, solely recognized by drilling, has a vertical extent of 800 m and a maximum width of 180 m. The pipe consists of angular clasts of granodiorite cemented by quartz, chalcopyrite, bornite, anhydrite, and calcite. Biotite 40Ar/ 39Ar dates suggest a minimum age of 61.5??0.7 Ma for the host Copper Creek Granodiorite and 40Ar/39Ar dates on hydrothermal sericite indicate an age of 61.0??0.5 Ma for copper mineralization. Fluid inclusion studies suggest that a supercritical fluid with a salinity of approximately 10 wt.% NaCl equiv. condensed to a dilute aqueous vapor (1-2.8 wt.% NaCl equiv.) and a hypersaline brine (33.4-35.1 wt.% NaCl equiv.). Minimum trapping temperatures are 375??C and trapping depths are estimated at 2 km. Sulfur isotope fractionation of cogenetic anhydrite and chalcopyrite yields a temperature of mineralization of 469??25??C. Calculated oxygen and hydrogen isotope values for fluids in equilibrium with quartz and sericite range from 10.2??? to 13.4??? and -60??? to -39???, respectively, suggesting that the mineralizing fluid was dominantly magmatic. Evidence from the stable isotope and fluid inclusion analyses suggests that the fluids responsible for Cu mineralization within the Mammoth breccia pipe exsolved from a gray porphyry phase found at the base of the breccia pipe. ?? Springer-Verlag 2008.

  12. Infrasound-array-element frequency response: in-situ measurement and modeling

    NASA Astrophysics Data System (ADS)

    Gabrielson, T.

    2011-12-01

    Most array elements at the infrasound stations of the International Monitoring System use some variant of a multiple-inlet pipe system for wind-noise suppression. These pipe systems have a significant impact on the overall frequency response of the element. The spatial distribution of acoustic inlets introduces a response dependence that is a function of frequency and of vertical and horizontal arrival angle; the system of inlets, pipes, and summing junctions further shapes that response as the signal is ducted to the transducer. In-situ measurements, using a co-located reference microphone, can determine the overall frequency response and diagnose problems with the system. As of July 2011, the in-situ frequency responses for 25 individual elements at 6 operational stations (I10, I53, I55, I56, I57, and I99) have been measured. In support of these measurements, a fully thermo-viscous model for the acoustics of these multiple-inlet pipe systems has been developed. In addition to measurements at operational stations, comparative analyses have been done on experimental systems: a multiple-inlet radial-pipe system with varying inlet hole size; a one-quarter scale model of a 70-meter rosette system; and vertical directionality of a small rosette system using aircraft flyovers. [Funded by the US Army Space and Missile Defense Command

  13. On the universality of inertial energy in the log layer of turbulent boundary layer and pipe flows

    NASA Astrophysics Data System (ADS)

    Chung, D.; Marusic, I.; Monty, J. P.; Vallikivi, M.; Smits, A. J.

    2015-07-01

    Recent experiments in high Reynolds number pipe flow have shown the apparent obfuscation of the behaviour in spectra of streamwise velocity fluctuations (Rosenberg et al. in J Fluid Mech 731:46-63, 2013). These data are further analysed here from the perspective of the behaviour in second-order structure functions, which have been suggested as a more robust diagnostic to assess scaling behaviour. A detailed comparison between pipe flows and boundary layers at friction Reynolds numbers of 5000-20,000 reveals subtle differences. In particular, the slope of the pipe flow structure function decreases with increasing wall distance, departing from the expected slope in a manner that is different to boundary layers. Here, , the slope of the log law in the streamwise turbulence intensity profile at high Reynolds numbers. Nevertheless, the structure functions for both flows recover the slope in the log layer sufficiently close to the wall, provided the Reynolds number is also high enough to remain in the log layer. This universality is further confirmed in very high Reynolds number data from measurements in the neutrally stratified atmospheric surface layer. A simple model that accounts for the `crowding' effect near the pipe axis is proposed in order to interpret the aforementioned differences.

  14. Numerical analysis of flow resistance and heat transfer in the transitional regime of pipe flow with twisted-tape turbulators

    NASA Astrophysics Data System (ADS)

    Rossi, R.; Cattani, L.; Mocerino, A.; Bozzoli, F.; Rainieri, S.; Caminati, R.; Pagliarini, G.

    2017-11-01

    In this paper, we present the numerical analysis of the fully developed ow and heat transfer in pipes equipped with twisted-tape inserts in the laminar to transitional flow regime. The flow Reynolds number ranges from 210 to 3100 based on the pipe diameter, whereas the Prandtl number of the working fluid, a 40% mixture of water and ethylene glycol, is about 45 at the average film temperature. The numerical study is carried out via Scale Adaptive Simulations (SAS) where the k-ω SST model is employed for turbulence modeling. Using SAS and low-dissipation discretization schemes, the present study shows that it is possible to capture the transition from the laminar regime to the pulsating or pseudo-laminar flow regime induced by the twisted-tape at low Reynolds numbers, as well as the transition to moderate turbulent regime at the higher, yet non-turbulent for smooth pipes, range of Reynolds numbers. Numerical results, validated against experiments performed in a dedicated test rig, show very good agreement with measured data and an increase of the friction factor and Nusselt number in the range of 4 to 7 times and 6 to 15 times, respectively, of the values for an empty pipe.

  15. Presidential Green Chemistry Challenge: 2012 Greener Reaction Conditions Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 2012 award winner, Cytec Industries, developed the MAX HT sodalite scale inhibitor for heat exchangers and pipes in the Bayer process, which converts bauxite into alumina.

  16. Large Eddy Simulation of Turbulent Flow in a Ribbed Pipe

    NASA Astrophysics Data System (ADS)

    Kang, Changwoo; Yang, Kyung-Soo

    2011-11-01

    Turbulent flow in a pipe with periodically wall-mounted ribs has been investigated by large eddy simulation with a dynamic subgrid-scale model. The value of Re considered is 98,000, based on hydraulic diameter and mean bulk velocity. An immersed boundary method was employed to implement the ribs in the computational domain. The spacing of the ribs is the key parameter to produce the d-type, intermediate and k-type roughness flows. The mean velocity profiles and turbulent intensities obtained from the present LES are in good agreement with the experimental measurements currently available. Turbulence statistics, including budgets of the Reynolds stresses, were computed, and analyzed to elucidate turbulence structures, especially around the ribs. In particular, effects of the ribs are identified by comparing the turbulence structures with those of smooth pipe flow. The present investigation is relevant to the erosion/corrosion that often occurs around a protruding roughness in a pipe system. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0008457).

  17. FBG-based sensorized light pipe for robotic intraocular illumination facilitates bimanual retinal microsurgery.

    PubMed

    Horise, Yuki; He, Xingchi; Gehlbach, Peter; Taylor, Russell; Iordachita, Iulian

    2015-01-01

    In retinal surgery, microsurgical instruments such as micro forceps, scissors and picks are inserted through the eye wall via sclerotomies. A handheld intraocular light source is typically used to visualize the tools during the procedure. Retinal surgery requires precise and stable tool maneuvers as the surgical targets are micro scale, fragile and critical to function. Retinal surgeons typically control an active surgical tool with one hand and an illumination source with the other. In this paper, we present a "smart" light pipe that enables true bimanual surgery via utilization of an active, robot-assisted source of targeted illumination. The novel sensorized smart light pipe measures the contact force between the sclerotomy and its own shaft, thereby accommodating the motion of the patient's eye. Forces at the point of contact with the sclera are detected by fiber Bragg grating (FBG) sensors on the light pipe. Our calibration and validation results demonstrate reliable measurement of the contact force as well as location of the sclerotomy. Preliminary experiments have been conducted to functionally evaluate robotic intraocular illumination.

  18. BARNARD 59: NO EVIDENCE FOR FURTHER FRAGMENTATION

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roman-Zuniga, C. G.; Frau, P.; Girart, J. M.

    2012-03-10

    The dense molecular clump at the center of the Barnard 59 (B59) complex is the only region in the Pipe Nebula that has formed a small, stellar cluster. The previous analysis of a high-resolution near-IR dust extinction map revealed that the nuclear region in B59 is a massive, mostly quiescent clump of 18.9 M{sub Sun }. The clump shows a monolithic profile, possibly indicating that the clump is on the way to collapse, with no evident fragmentation that could lead to another group of star systems. In this paper, we present new analysis that compares the dust extinction map withmore » a new dust emission radio-continuum map of higher spatial resolution. We confirm that the clump does not show any significant evidence for prestellar fragmentation at scales smaller than those probed previously.« less

  19. Spiral blood flows in an idealized 180-degree curved artery model

    NASA Astrophysics Data System (ADS)

    Bulusu, Kartik V.; Kulkarni, Varun; Plesniak, Michael W.

    2017-11-01

    Understanding of cardiovascular flows has been greatly advanced by the Magnetic Resonance Velocimetry (MRV) technique and its potential for three-dimensional velocity encoding in regions of anatomic interest. The MRV experiments were performed on a 180-degree curved artery model using a Newtonian blood analog fluid at the Richard M. Lucas Center at Stanford University employing a 3 Tesla General Electric (Discovery 750 MRI system) whole body scanner with an eight-channel cardiac coil. Analysis in two regions of the model-artery was performed for flow with Womersley number=4.2. In the entrance region (or straight-inlet pipe) the unsteady pressure drop per unit length, in-plane vorticity and wall shear stress for the pulsatile, carotid artery-based flow rate waveform were calculated. Along the 180-degree curved pipe (curvature ratio =1/7) the near-wall vorticity and the stretching of the particle paths in the vorticity field are visualized. The resultant flow behavior in the idealized curved artery model is associated with parameters such as Dean number and Womersley number. Additionally, using length scales corresponding to the axial and secondary flow we attempt to understand the mechanisms leading to the formation of various structures observed during the pulsatile flow cycle. Supported by GW Center for Biomimetics and Bioinspired Engineering (COBRE), MRV measurements in collaboration with Prof. John K. Eaton and, Dr. Chris Elkins at Stanford University.

  20. Identification and characterization of steady and occluded water in drinking water distribution systems.

    PubMed

    Tong, Huiyan; Zhao, Peng; Zhang, Hongwei; Tian, Yimei; Chen, Xi; Zhao, Weigao; Li, Mei

    2015-01-01

    Deterioration and leakage of drinking water in distribution systems have been a major issue in the water industry for years, which are associated with corrosion. This paper discovers that occluded water in the scales of the pipes has an acidic environment and high concentration of iron, manganese, chloride, sulfate and nitrate, which aggravates many pipeline leakage accidents. Six types of water samples have been analyzed under the flowing and stagnant periods. Both the water in the exterior of the tubercles and stagnant water carry suspended iron particles, which explains the occurrence of "red water" when the system hydraulic conditions change. Nitrate is more concentrated in occluded water under flowing condition in comparison with that in flowing water. However, the concentration of nitrate in occluded water under stagnant condition is found to be less than that in stagnant water. A high concentration of manganese is found to exist in steady water, occluded water and stagnant water. These findings impact secondary pollution and the corrosion of pipes and containers used in drinking water distribution systems. The unique method that taking occluded water from tiny holes which were drilled from the pipes' exteriors carefully according to the positions of corrosion scales has an important contribution to research on corrosion in distribution systems. And this paper furthers our understanding and contributes to the growing body of knowledge regarding occluded environments in corrosion scales. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. 58. ROASTER ADDITION INTERIOR FROM EAST, VIEW OF DISCHARGE CREW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    58. ROASTER ADDITION INTERIOR FROM EAST, VIEW OF DISCHARGE CREW DRIVE WITH GAS PIPING FOR HEARTH FIRING. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  2. Development of a Remote External Repair Tool for Damaged or Defective Polyethylene Pipe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kenneth H. Green; Willie E. Rochefort; Nick Wannenmacher

    2006-06-30

    Current procedures for repairing polyethylene (PE) gas pipe require excavation, isolation, and removal of the damaged section of pipe followed by fusing a new section of pipe into place. These techniques are costly and very disruptive. An alternative repair method was developed at Timberline Tool with support from Oregon State University (OSU) and funding by the U. S. Department of Energy National Energy Technology Laboratory (DOE/NETL). This project was undertaken to design, develop and test a tool and method for repairing damaged PE pipe remotely and externally in situ without squeezing off the flow of gas, eliminating the need formore » large-scale excavations. Through an iterative design and development approach, a final engineered prototype was developed that utilizes a unique thermo-chemical and mechanical process to apply a permanent external patch to repair small nicks, gouges and punctures under line pressure. The project identified several technical challenges during the design and development process. The repair tool must be capable of being installed under live conditions and operate in an 18-inch keyhole. This would eliminate the need for extensive excavations thus reducing the cost of the repair. Initially, the tool must be able to control the leak by encapsulating the pipe and apply slight pressure at the site of damage. Finally, the repair method must be permanent at typical operating pressures. The overall results of the project have established a permanent external repair method for use on damaged PE gas pipe in a safe and cost-effective manner. The engineered prototype was subjected to comprehensive testing and evaluation to validate the performance. Using the new repair tool, samples of 4-inch PE pipe with simulated damage were successfully repaired under line pressure to the satisfaction of DOE/NETL and the following natural gas companies: Northwest Natural; Sempra Energy, Southwest Gas Corporation, Questar, and Nicor. However, initial results of accelerated age testing on repaired pipe samples showed that the high density polyethylene (HDPE) pipe patch material developed a small crack at the high stress areas surrounding the patched hole within the first 48 hours of hot water testing, indicating that the patch material has a 25-year lifespan. Based on these results, further research is continuing to develop a stronger repair patch for a satisfactory 50-year patch system. Additional tests were also conducted to evaluate whether any of the critical performance properties of the PE pipe were reduced or compromised by the repair technique. This testing validated a satisfactory 50-year patch system for the pipe.« less

  3. Role of large-scale motions to turbulent inertia in turbulent pipe and channel flows

    NASA Astrophysics Data System (ADS)

    Hwang, Jinyul; Lee, Jin; Sung, Hyung Jin

    2015-11-01

    The role of large-scale motions (LSMs) to the turbulent inertia (TI) term (the wall-normal gradient of the Reynolds shear stress) is examined in turbulent pipe and channel flows at Reτ ~ 930 . The TI term in the mean momentum equation represents the net force of inertia exerted by the Reynolds shear stress. Although the turbulence statistics characterizing the internal turbulent flows are similar close to the wall, the TI term differs in the logarithmic region due to the different characteristics of LSMs (λx > 3 δ) . The contribution of the LSMs to the TI term and the Reynolds shear stress in the channel flow is larger than that in the pipe flow. The LSMs in the logarithmic region act like a mean momentum source (where TI >0) even the TI profile is negative above the peak of the Reynolds shear stress. The momentum sources carried by the LSMs are related to the low-speed regions elongated in the downstream, revealing that momentum source-like motions occur in the upstream position of the low-speed structure. The streamwise extent of this structure is relatively long in the channel flow, whereas the high-speed regions on the both sides of the low-speed region in the channel flow are shorter and weaker than those in the pipe flow. This work was supported by the Creative Research Initiatives (No. 2015-001828) program of the National Research Foundation of Korea (MSIP) and partially supported by KISTI under the Strategic Supercomputing Support Program.

  4. Construction and 1st Experiment of the 500-meter and 1000-meter DC Superconducting Power Cable in Ishikari

    NASA Astrophysics Data System (ADS)

    Yamaguchi, S.; Ivanov, Y.; Watanabe, H.; Chikumoto, N.; Koshiduka, H.; Hayashi, K.; Sawamura, T.

    Ishikari project constructs two lines. The length of the Line 1 is 500 m, and connects the photovoltaic cell to the internet-data center. The other line is 1 km length, and it is a test facility and called Line 2. The structures of the cable systems are not same to test their performance. The construction was started from 2014 in the field, the Line 1 was completed in May 2015, and it was cooled down and do the current experiment, and warmed up. The Line 2 is almost complete in October 2015. It will be tested in November and December, 2015. In order to reduce the stress of the cable induced by the thermal expansion and contraction, we adopted the way of the helical deformation of the cable. The force of the cable is reduced to 1/3 of an usual cable test. Because the cryogenic pipes are welded in the field and we cannot use the baking of the vacuum chamber of the cryogenic pipe, a new vacuum pumping method was proposed and tested for the cryogenic pipe. Since the straight pipes are used to compose the cryogenic pipe, the pressure drop of the circulation would be 1/100 of the corrugated pipe in the present condition, and it is suitable for longer cable system. The heat leak of the cryogenic pipe is ∼1.4W/m including the cable pipe's and the return pipe's. The heat leak of the current lead is ∼30W/kA in the test bench. Finally the current of 6kA/3 sec and the current of 5kA/15 min were achieved in Line 1. The reduction of heat leak will be a major subject of the longer cable system. The cost of the construction will be almost twice higher than that of the copper and aluminum over-head line with the iron tower in the present Japan. The cost construction of the over-head line is an average value, and depends on the newspaper.

  5. Visualisation of flow patterns in straight and C-shape thermosyphons

    NASA Astrophysics Data System (ADS)

    Ong, K. S.; Tshai, K. H.; Firwana, A.

    2017-04-01

    A heat pipe is a passive heat transfer device capable of transferring a large quantity of heat effectively and efficiently over a long distance and with a small temperature difference between the heat source and heat sink. A heat pipe consists of a metal pipe initially vacuumed and then filled with a small quantity of fluid inside. The pipe is separated into a heating (evaporator) section and a cooling (condenser) section by an adiabatic section. In a run-around-coil heating, ventilation and air conditioning system, a wrap-around heat pipe heat exchanger could be employed to increase dehumidification and to reduce cooling costs. The thermal performance of a thermosyphon is dependent upon type of fill liquid, fill ratio, power input, pipe inclination and pipe dimensions. The boiling and condensation processes that occur inside a thermosyphon are quite complex. During operation, dry-out, burn-out or boiling limit, entrainment or flooding limit and geysering occur. These phenomena would lead to non-uniform axial wall temperature distribution in the pipe, or worse still, ineffective operation. In order to have a better understanding of the internal heat transfer phenomena, a visual study using transparent glass tubes and high speed camera recording of the internal flow patterns would be most helpful. This paper reports on an experimental investigation conducted to visualise the flow patterns in straight and C-shape thermosyphons. The pictures recorded enabled the internal flow boiling and condensation pattern occurring inside a straight and a C-shape thermosyphon to be observed. The thermosyphons were fabricated from 10 mm O/D × 8 mm I/D × 300 mm long glass tubes and filled with water with fill ratios from 0.5 - 1.5. The evaporator sections of the thermosyphons were immersed into a hot water tank that was electrically heated from cold at ambient temperature till boiling. Cooling of the condenser section was achieved using a fan. Preliminary results showed that dry-out occurred earlier at lower evaporator temperatures with small fill ratios. Further investigations to determine saturation and thermosyphon wall temperatures with various fill liquids and at different fill ratios, inclinations and pipe sizes are necessary with a more sophisticated video recording system.

  6. Transition of unsteady velocity profiles with reverse flow

    NASA Astrophysics Data System (ADS)

    Das, Debopam; Arakeri, Jaywant H.

    1998-11-01

    This paper deals with the stability and transition to turbulence of wall-bounded unsteady velocity profiles with reverse flow. Such flows occur, for example, during unsteady boundary layer separation and in oscillating pipe flow. The main focus is on results from experiments in time-developing flow in a long pipe, which is decelerated rapidly. The flow is generated by the controlled motion of a piston. We obtain analytical solutions for laminar flow in the pipe and in a two-dimensional channel for arbitrary piston motions. By changing the piston speed and the length of piston travel we cover a range of values of Reynolds number and boundary layer thickness. The velocity profiles during the decay of the flow are unsteady with reverse flow near the wall, and are highly unstable due to their inflectional nature. In the pipe, we observe from flow visualization that the flow becomes unstable with the formation of what appears to be a helical vortex. The wavelength of the instability [simeq R: similar, equals]3[delta] where [delta] is the average boundary layer thickness, the average being taken over the time the flow is unstable. The time of formation of the vortices scales with the average convective time scale and is [simeq R: similar, equals]39/([Delta]u/[delta]), where [Delta]u=(umax[minus sign]umin) and umax, umin and [delta] are the maximum velocity, minimum velocity and boundary layer thickness respectively at each instant of time. The time to transition to turbulence is [simeq R: similar, equals]33/([Delta]u/[delta]). Quasi-steady linear stability analysis of the velocity profiles brings out two important results. First that the stability characteristics of velocity profiles with reverse flow near the wall collapse when scaled with the above variables. Second that the wavenumber corresponding to maximum growth does not change much during the instability even though the velocity profile does change substantially. Using the results from the experiments and the stability analysis, we are able to explain many aspects of transition in oscillating pipe flow. We postulate that unsteady boundary layer separation at high Reynolds numbers is probably related to instability of the reverse flow region.

  7. Reactive Transport in a Pipe in Soluble Rock: a Theoretical and Experimental Study

    NASA Astrophysics Data System (ADS)

    Li, W.; Opolot, M.; Sousa, R.; Einstein, H. H.

    2015-12-01

    Reactive transport processes within the dominant underground flow pathways such as fractures can lead to the widening or narrowing of rock fractures, potentially altering the flow and transport processes in the fractures. A flow-through experiment was designed to study the reactive transport process in a pipe in soluble rock to serve as a simplified representation of a fracture in soluble rock. Assumptions were made to formulate the problem as three coupled, one-dimensional partial differential equations: one for the flow, one for the transport and one for the radius change due to dissolution. Analytical and numerical solutions were developed to predict the effluent concentration and the change in pipe radius. The positive feedback of the radius increase is captured by the experiment and the numerical model. A comparison between the experiment and the simulation results demonstrates the validity of the analytical and numerical models.

  8. Experimental evidence of a helical, supercritical instability in pipe flow of shear thinning fluids

    NASA Astrophysics Data System (ADS)

    Picaut, L.; Ronsin, O.; Caroli, C.; Baumberger, T.

    2017-08-01

    We study experimentally the flow stability of entangled polymer solutions extruded through glass capillaries. We show that the pipe flow becomes linearly unstable beyond a critical value (Wic≃5 ) of the Weissenberg number, via a supercritical bifurcation which results in a helical distortion of the extrudate. We find that the amplitude of the undulation vanishes as the aspect ratio L /R of the capillary tends to zero, and saturates for large L /R , indicating that the instability affects the whole pipe flow, rather than the contraction or exit regions. These results, when compared to previous theoretical and experimental works, lead us to argue that the nature of the instability is controlled by the level of shear thinning of the fluids. In addition, we provide strong hints that the nonlinear development of the instabiilty is mitigated, in our system, by the gradual emergence of gross wall slip.

  9. Approach for removing ghost-images in remote field eddy current testing of ferromagnetic pipes

    NASA Astrophysics Data System (ADS)

    Luo, Q. W.; Shi, Y. B.; Wang, Z. G.; Zhang, W.; Zhang, Y.

    2016-10-01

    In the non-destructive testing of ferromagnetic pipes based on remote field eddy currents, an array of sensing coils is often used to detect local defects. While testing, the image that is obtained by sensing coils exhibits a ghost-image, which originates from both the transmitter and sensing coils passing over the same defects in pipes. Ghost-images are caused by transmitters and lead to undesirable assessments of defects. In order to remove ghost-images, two pickup coils are coaxially set to each other in remote field. Due to the time delay between differential signals tested by the two pickup coils, a Wiener deconvolution filter is used to identify the artificial peaks that lead to ghost-images. Because the sensing coils and two pickup coils all receive the same signal from one transmitter, they all contain the same artificial peaks. By subtracting the artificial peak values obtained by the two pickup coils from the imaging data, the ghost-image caused by the transmitter is eliminated. Finally, a relatively highly accurate image of local defects is obtained by these sensing coils. With proposed method, there is no need to subtract the average value of the sensing coils, and it is sensitive to ringed defects.

  10. Approach for removing ghost-images in remote field eddy current testing of ferromagnetic pipes.

    PubMed

    Luo, Q W; Shi, Y B; Wang, Z G; Zhang, W; Zhang, Y

    2016-10-01

    In the non-destructive testing of ferromagnetic pipes based on remote field eddy currents, an array of sensing coils is often used to detect local defects. While testing, the image that is obtained by sensing coils exhibits a ghost-image, which originates from both the transmitter and sensing coils passing over the same defects in pipes. Ghost-images are caused by transmitters and lead to undesirable assessments of defects. In order to remove ghost-images, two pickup coils are coaxially set to each other in remote field. Due to the time delay between differential signals tested by the two pickup coils, a Wiener deconvolution filter is used to identify the artificial peaks that lead to ghost-images. Because the sensing coils and two pickup coils all receive the same signal from one transmitter, they all contain the same artificial peaks. By subtracting the artificial peak values obtained by the two pickup coils from the imaging data, the ghost-image caused by the transmitter is eliminated. Finally, a relatively highly accurate image of local defects is obtained by these sensing coils. With proposed method, there is no need to subtract the average value of the sensing coils, and it is sensitive to ringed defects.

  11. Guided wave radiation from a point source in the proximity of a pipe bend

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brath, A. J.; Nagy, P. B.; Simonetti, F.

    Throughout the oil and gas industry corrosion and erosion damage monitoring play a central role in managing asset integrity. Recently, the use of guided wave technology in conjunction with tomography techniques has provided the possibility of obtaining point-by-point maps of wall thickness loss over the entire volume of a pipeline section between two ring arrays of ultrasonic transducers. However, current research has focused on straight pipes while little work has been done on pipe bends which are also the most susceptible to developing damage. Tomography of the bend is challenging due to the complexity and computational cost of the 3-Dmore » elastic model required to accurately describe guided wave propagation. To overcome this limitation, we introduce a 2-D anisotropic inhomogeneous acoustic model which represents a generalization of the conventional unwrapping used for straight pipes. The shortest-path ray-tracing method is then applied to the 2-D model to compute ray paths and predict the arrival times of the fundamental flexural mode, A0, excited by a point source on the straight section of pipe entering the bend and detected on the opposite side. Good agreement is found between predictions and experiments performed on an 8” diameter (D) pipe with 1.5 D bend radius. The 2-D model also reveals the existence of an acoustic lensing effect which leads to a focusing phenomenon also confirmed by the experiments. The computational efficiency of the 2-D model makes it ideally suited for tomography algorithms.« less

  12. The Collection of Ice in Jet A-1 Fuel Pipes

    NASA Astrophysics Data System (ADS)

    Maloney, Thomas C.

    Ice collection and blockages in fuel systems have been of interest to the aerospace community since their discovery in the late 1950's when a B-52 crashed. A recent growth of interest was provoked by several incidents that occurred within the last few years. This study seeks to understand the underlying principles of ice growth in fuel flow systems. Tests were performed in a recirculated fuel system with a fuel tank that held approximately 115 gallons of Jet A-1 fuel and ice accumulation was observed in two removable test pipes. The setup was in an altitude chamber capable of -60 °F and the experiments involved full scale flow components. Initially, tests were done to better understand the system and variables that effected accumulation. First, initial conditions within the test pipes were varied. Next, pipe geometry, pipe surface properties, initial water content of the fuel and heat transfer from the fuel pipe were varied. As a result of the tests, observations were made about other effects involved in the study. The effects include: the result of sequentially run tests, the effect of the fuel on the freezing temperature of the entrained water, the effect of ice accumulation on pipe welds, and the effect of the test pipe entrance and exit flow conditions on ice accumulation. The results of initial tests were qualitative. Later quantitative tests were done to demonstrate the dependence of temperature, Reynolds number, and heat transfer on ice accumulation. Tests were quantified with a pressure increase across the pipe sections that was normalized by the expected theoretical initial pressure. As a result of these tests the effect of contamination in the fuel was revealed. For ease of reference, the initial tests were called "stage I" and the later tests were called "stage II". The results of stage I showed that accumulation of soft ice was greatest when a layer of hard ice had initially formed on the pipe surface. Stainless steel collected more ice than Teflon® and there was a lack of a preferential accumulation region downstream of a pipe bend. A greater heat transfer from the pipe increased ice accumulation for aluminum that was made rough with 80 grit sand paper, and for Teflon®. Water was shown to collect in the pipe system as the number of tests increased and the freeze temperature of either the hard or soft ice was about 0 °C. Finally, results of "stage I" tests showed that stainless steel pipe welds were a preferred sight for ice to accumulate. Repeatability was done first in stage II and the normalized pressure increase for two 3/42 un-insulated pipe tests were within 7%. Normalized pressure increase across a pipe was shown to increase as Reynolds number decreased. A 50% increase in Reynolds number led to a 40% decrease in characteristic normalized pressure increase (CNPI). Tests were done at three temperatures and ice accumulated the most at -11 °C. The CNPI at -11 °C was about three times greater than the CNPI at -7.4 °C and about sixty times greater than the CNPI at -19.4 C. A greater heat transfer from the fuel pipe increased ice accumulation. For the amount of time that the tests ran, the total normalized pressure increase was about .9 greater for an un-insulated pipe than for an insulated pipe. Contamination in the fuel increased the amount of soft ice that collected in the system. The CNPI for the more contaminated fuel was more than double the case with less contaminated fuel. Possible solutions for the prevention or decrease of ice accumulation in aircraft fuel systems based on the results of this study are insulated pipes, a change in the type of pipe material, a higher fuel flow rate and cleaner fuel. The fuel temperature could also be altered to avoid temperatures where the most ice accumulates.

  13. 46 CFR 108.213 - Heating requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... accommodation space must be heated by a heating system that can maintain at least 20°C. (68°F.). (b) Radiators... pipe in an accommodation space, leading to a radiator or other heating apparatus must be insulated. ...

  14. Development of optimized PPP insulated pipe-cable systems in the commercial voltage range

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Allam, E.M.; McKean, A.L.

    1992-05-01

    The primary objectives of this project included the development of an alternate domestic source of Paper-Polypropylene-Paper (PPP) laminate and the development of optimized designs for PPP-insulated pipe-type cable systems in the commercial voltage range. The development of a domestic source of PPP laminate was successfully completed. This laminate was utilized throughout the program for fabrication of full-size prototype cables submitted for laboratory qualification tests. Selected cables at rated voltages of 138, 230 and 345kV have been designed, fabricated and subjected to the series of qualification tests leading to full laboratory qualification. An optimized design of 2000 kcmil, 345kV cable insulatedmore » with 600 mils of domestic PPP laminate was fabricated and successfully passed all laboratory qualification tests. This cable design was subsequently installed at Waltz Mill to undergo the series of field tests leading to full commercial qualification.« less

  15. Development of optimized PPP insulated pipe-cable systems in the commercial voltage range. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Allam, E.M.; McKean, A.L.

    1992-05-01

    The primary objectives of this project included the development of an alternate domestic source of Paper-Polypropylene-Paper (PPP) laminate and the development of optimized designs for PPP-insulated pipe-type cable systems in the commercial voltage range. The development of a domestic source of PPP laminate was successfully completed. This laminate was utilized throughout the program for fabrication of full-size prototype cables submitted for laboratory qualification tests. Selected cables at rated voltages of 138, 230 and 345kV have been designed, fabricated and subjected to the series of qualification tests leading to full laboratory qualification. An optimized design of 2000 kcmil, 345kV cable insulatedmore » with 600 mils of domestic PPP laminate was fabricated and successfully passed all laboratory qualification tests. This cable design was subsequently installed at Waltz Mill to undergo the series of field tests leading to full commercial qualification.« less

  16. Stormwater Infrastructure Effects on Urban Nitrogen Budgets

    NASA Astrophysics Data System (ADS)

    Hale, R. L.; Turnbull, L.; Earl, S.; Moratto, S.; Shorts, D.; Grimm, N. B.

    2012-12-01

    The effects of urbanization on downstream ecosystems, particularly due to changes in nutrient inputs and altered hydrology are well studied. Less is known, however, about nutrient transport and processing within urban watersheds. Previous research has focused on the roles of land cover and land use but drainage system design and configuration also are apt to play a significant role in controlling the transport of water and nutrients downstream. Furthermore, variability in drainage systems within and between cities may lead to differences in the effects of urbanization on downstream ecosystems over time and space. We established a nested stormwater sampling network with 10 watersheds ranging in size from 5 to 22,000 ha in the Indian Bend Wash watershed in Scottsdale, AZ. Small (< 200ha) watersheds had uniform land cover (medium-density residential) but were drained by a variety of stormwater infrastructure including surface runoff, pipes, natural or engineered washes, and retention basins. We quantified discharge and precipitation at the outflow of each subwatershed and collected stormwater and rainfall samples for analyses of dissolved nitrogen species and δ15N, δ18O and Δ17O isotopes of nitrate (NO3) over two years. We also measured potential denitrification rates in washes and retention basins within our sites, and collected soil and pavement samples to describe pools of N within our watersheds. We used these data in combination with literature data on soil N transformations to construct N budgets for each watershed for a single event and at annual scales. We found that stormwater infrastructure type strongly affects N retention. Watersheds with surface or pipe drainage were sources of N downstream, whereas watersheds drained by washes or retention basins retained 70-99% of N inputs in rainfall. Event scale N retention was strongly correlated with hydrologic connectivity, as measured by runoff coefficients. Differences in δ15N, δ18O, and Δ17O isotopes of NO3 suggested that watersheds with decreased hydrologic connectivity were more biogeochemically active, that is, exported NO3 had less of an atmospheric signal than did NO3 exported from piped watersheds. Overall, we find that stormwater infrastructure significantly alters hydrologic connectivity and that these changes in hydrology are driving patterns in N export and retention.

  17. Evaluation of the effect of sulfate, alkalinity and disinfector on iron release of iron pipe and iron corrosion scale characteristics under water quality changing condition using response surface methodology

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Shi, Baoyou; Zhang, Weiyu; Guo, Jianbo; Wu, Nana; Liu, Xinyuan

    2018-02-01

    The response surface methodology (RSM), particularly Box-Behnken design model, was used in this study to evaluate the sulfate, alkalinity and free chlorine on iron release of pipe with groundwater supply history and its iron corrosion scale characteristics under water quality changing experiment. The RSM results together with response surface contour plots indicated that the iron release of pipe section reactors was positively related with Larson Ratio and free chlorine. The thin Corrosion scales with groundwater supply history upon collection site contained Fe3O4 (18%), α-FeOOH (64%), FeCO3 (9%), β-FeOOH (8%) and γ-FeOOH (5%), besides their averaged amorphous iron oxide content was 13.6%. After the RSM water quality changing experiment, Fe3O4, amorphous iron oxide and intermediate iron products (FeCO3, Green Rust (GR)) content on scale of Cl2Rs increased, while their α-FeOOH contents decreased and β-FeOOH disappeared. The high iron released Cl2Rs receiving higher LR water (1.40-2.04) contained highest FeCO3 (20%) and amorphous iron oxide (42%), while the low iron release Cl2Rs receiving lower LR water (0.52-0.73) had higher GR(6.5%) and the amorphous iron oxide (23.7%). In high LR water (>0.73), the thin and non-protective corrosion scale containing higher amorphous iron oxide, Fe(II) derived from new produced Fe3O4 or FeCO3 or GR was easy for oxidants and sulfate ions penetration, and had higher iron release. However the same unstable corrosion scale didn’t have much iron release in low LR water (≤0.73). RSM experiment indicated that iron release of these unstable corrosion scales had close relationship with water quality (Larson Ratio and disinfectant). Optimizing the water quality of new source water and using reasonable water purification measures can help to eliminate the red water case.

  18. The energy transfer mechanism of a perturbed solid-body rotation flow in a rotating pipe

    NASA Astrophysics Data System (ADS)

    Feng, Chunjuan; Liu, Feng; Rusak, Zvi; Wang, Shixiao

    2017-04-01

    Three-dimensional direct numerical simulations of a solid-body rotation superposed on a uniform axial flow entering a rotating constant-area pipe of finite length are presented. Steady in time profiles of the radial, axial, and circumferential velocities are imposed at the pipe inlet. Convective boundary conditions are imposed at the pipe outlet. The Wang and Rusak (Phys. Fluids 8:1007-1016, 1996. doi: 10.1063/1.86882) axisymmetric instability mechanism is retrieved at certain operational conditions in terms of incoming flow swirl levels and the Reynolds number. However, at other operational conditions there exists a dominant, three-dimensional spiral type of instability mode that is consistent with the linear stability theory of Wang et al. (J. Fluid Mech. 797: 284-321, 2016). The growth of this mode leads to a spiral type of flow roll-up that subsequently nonlinearly saturates on a large amplitude rotating spiral wave. The energy transfer mechanism between the bulk of the flow and the perturbations is studied by the Reynolds-Orr equation. The production or loss of the perturbation kinetic energy is combined of three components: the viscous loss, the convective loss at the pipe outlet, and the gain of energy at the outlet through the work done by the pressure perturbation. The energy transfer in the nonlinear stage is shown to be a natural extension of the linear stage with a nonlinear saturated process.

  19. Development of a Flexible Broadband Rayleigh Waves Comb Transducer with Nonequidistant Comb Interval for Defect Detection of Thick-Walled Pipelines

    PubMed Central

    He, Cunfu; Yan, Lyu; Zhang, Haijun

    2018-01-01

    It is necessary to develop a transducer that can quickly detect the inner and outer wall defects of thick-walled pipes, in order to ensure the safety of such pipes. In this paper, a flexible broadband Rayleigh-waves comb transducer based on PZT (lead zirconate titanate) for defect detection of thick-walled pipes is studied. The multiple resonant coupling theory is used to expand the transducer broadband and the FEA (Finite Element Analysis) method is used to optimize transducer array element parameters. Optimization results show that the best array element parameters of the transducer are when the transducer array element length is 30 mm, the thickness is 1.2 mm, the width of one end of is 1.5 mm, and the other end is 3 mm. Based on the optimization results, such a transducer was fabricated and its performance was tested. The test results were consistent with the finite-element simulation results, and the −3 dB bandwidth of the transducer reached 417 kHz. Transducer directivity test results show that the Θ−3dB beam width was equal to 10 °, to meet the defect detection requirements. Finally, defects of thick-walled pipes were detected using the transducer. The results showed that the transducer could detect the inner and outer wall defects of thick-walled pipes within the bandwidth. PMID:29498636

  20. Characteristics of a 1.6 W Gifford-McMahon Cryocooler with a Double Pipe Regenerator

    NASA Astrophysics Data System (ADS)

    Masuyama, S.; Numazawa, T.

    2017-12-01

    This paper focuses on the second stage regenerator of a 4 K Gifford-McMahon (G-M) cryocooler. A three-layer layout of lead (Pb), HoCu2 and Gd2O2S spheres in the second stage regenerator derives a good performance at 4 K. After some modifications, we confirmed that the cooling power of 1.60 W at 4.2 K was achieved by using this three-layer layout. A two-stage G-M cryocooler is RDK-408D2 (SHI) and a compressor is C300G (SUZUKISHOKAN) with a rated electric input power of 7.3 kW at 60 Hz. In order to further improve, a double pipe regenerator was applied to the second stage regenerator. As a double pipe, a stainless steel pipe with thin wall was inserted in the coaxial direction into the second stage regenerator. The helium flow in the second stage regenerator is expected to be non-uniform flow because of the distribution of helium density and the imperfect packing of regenerator material. The double pipe regenerator is considered to have an effect of restraining the non-uniform flow. From the experimental results, the second stage cooling power of 1.67 W at 4.2 K and the first stage cooling power of 64.9 W at 50 K were achieved.

  1. Development of a Flexible Broadband Rayleigh Waves Comb Transducer with Nonequidistant Comb Interval for Defect Detection of Thick-Walled Pipelines.

    PubMed

    Zhao, Huamin; He, Cunfu; Yan, Lyu; Zhang, Haijun

    2018-03-02

    It is necessary to develop a transducer that can quickly detect the inner and outer wall defects of thick-walled pipes, in order to ensure the safety of such pipes. In this paper, a flexible broadband Rayleigh-waves comb transducer based on PZT (lead zirconate titanate) for defect detection of thick-walled pipes is studied. The multiple resonant coupling theory is used to expand the transducer broadband and the FEA (Finite Element Analysis) method is used to optimize transducer array element parameters. Optimization results show that the best array element parameters of the transducer are when the transducer array element length is 30 mm, the thickness is 1.2 mm, the width of one end of is 1.5 mm, and the other end is 3 mm. Based on the optimization results, such a transducer was fabricated and its performance was tested. The test results were consistent with the finite-element simulation results, and the -3 dB bandwidth of the transducer reached 417 kHz. Transducer directivity test results show that the Θ -3dB beam width was equal to 10 °, to meet the defect detection requirements. Finally, defects of thick-walled pipes were detected using the transducer. The results showed that the transducer could detect the inner and outer wall defects of thick-walled pipes within the bandwidth.

  2. Optimization of municipal pressure pumping station layout and sewage pipe network design

    NASA Astrophysics Data System (ADS)

    Tian, Jiandong; Cheng, Jilin; Gong, Yi

    2018-03-01

    Accelerated urbanization places extraordinary demands on sewer networks; thus optimization research to improve the design of these systems has practical significance. In this article, a subsystem nonlinear programming model is developed to optimize pumping station layout and sewage pipe network design. The subsystem model is expanded into a large-scale complex nonlinear programming system model to find the minimum total annual cost of the pumping station and network of all pipe segments. A comparative analysis is conducted using the sewage network in Taizhou City, China, as an example. The proposed method demonstrated that significant cost savings could have been realized if the studied system had been optimized using the techniques described in this article. Therefore, the method has practical value for optimizing urban sewage projects and provides a reference for theoretical research on optimization of urban drainage pumping station layouts.

  3. Heat transfer in space systems; Proceedings of the Symposium, AIAA/ASME Thermophysics and Heat Transfer Conference, Seattle, WA, June 18-20, 1990

    NASA Technical Reports Server (NTRS)

    Chan, S. H. (Editor); Anderson, E. E. (Editor); Simoneau, R. J. (Editor); Chan, C. K. (Editor); Pepper, D. W. (Editor)

    1990-01-01

    Theoretical and experimental studies of heat-tranfer in a space environment are discussed in reviews and reports. Topics addressed include a small-scale two-phase thermosiphon to cool high-power electronics, a low-pressure-drop heat exchanger with integral heat pipe, an analysis of the thermal performance of heat-pipe radiators, measurements of temperature and concentration fields in a rectangular heat pipe, and a simplified aerothermal heating method for axisymmetric blunt bodies. Consideration is given to entropy production in a shock wave, bubble-slug transition in a two-phase liquid-gas flow under microgravity, plasma arc welding under normal and zero gravity, the Microgravity Thaw Experiment, the flow of a thin film on stationary and rotating disks, an advanced ceramic fabric body-mounted radiator for Space Station Freedom phase 0 design, and lunar radiators with specular reflectors.

  4. The Challenge of Providing Safe Water with an Intermittently Supplied Piped Water Distribution System

    NASA Astrophysics Data System (ADS)

    Kumpel, E.; Nelson, K. L.

    2012-12-01

    An increasing number of urban residents in low- and middle-income countries have access to piped water; however, this water is often not available continuously. 84% of reporting utilities in low-income countries provide piped water for fewer than 24 hours per day (van den Berg and Danilenko, 2010), while no major city in India has continuous piped water supply. Intermittent water supply leaves pipes vulnerable to contamination and forces households to store water or rely on alternative unsafe sources, posing a health threat to consumers. In these systems, pipes are empty for long periods of time and experience low or negative pressure even when water is being supplied, leaving them susceptible to intrusion from sewage, soil, or groundwater. Households with a non-continuous supply must collect and store water, presenting more opportunities for recontamination. Upgrading to a continuous water supply, while an obvious solution to these challenges, is currently out of reach for many resource-constrained utilities. Despite its widespread prevalence, there are few data on the mechanisms causing contamination in an intermittent supply and the frequency with which it occurs. Understanding the impact of intermittent operation on water quality can lead to strategies to improve access to safe piped water for the millions of people currently served by these systems. We collected over 100 hours of continuous measurements of pressure and physico-chemical water quality indicators and tested over 1,000 grab samples for indicator bacteria over 14 months throughout the distribution system in Hubli-Dharwad, India. This data set is used to explore and explain the mechanisms influencing water quality when piped water is provided for a few hours every 3-5 days. These data indicate that contamination occurs along the distribution system as water travels from the treatment plant to reservoirs and through intermittently supplied pipes to household storage containers, while real-time measurements document variability in water quality throughout the 2-8 hour supply period. Our results show that piped water is not always safe water, but that safe water can be achieved in an intermittent supply under certain physical and operational conditions. Intermittent piped water supply is an important constraint on access to safe water in towns and cities in low-income countries, and strategies that improve these existing systems can help urban residents gain access to safe water. References van den Berg, C., and Danilenko, A. (2010). "The IBNET Water Supply and Sanitation Performance Blue Book: The International Benchmarking Network for Water and Sanitation Utilities Databook." World Bank Washington, DC.

  5. Transformation of Bisphenol A in Water Distribution Systems, A Pilot-scale Study

    EPA Science Inventory

    Halogenations of bisphenol A (BPA) in a pilot-scale water distribution system (WDS) of cement-lined ductile cast iron pipe were investigated under the condition: pH 7.3±0.3, water flow velocity of 1.0 m/s, and 25 °C ± 1 °C in water temperature. The testing water was chlorinated f...

  6. Scaling the Pipe: NASA EOS Terra Data Systems at 10

    NASA Technical Reports Server (NTRS)

    Wolfe, Robert E.; Ramapriyan, Hampapuram K.

    2010-01-01

    Standard products from the five sensors on NASA's Earth Observing System's (EOS) Terra satellite are being used world-wide for earth science research and applications. This paper describes the evolution of the Terra data systems over the last decade in which the distributed systems that produce, archive and distribute high quality Terra data products were scaled by two orders of magnitude.

  7. Spatial optimization for decentralized non-potable water reuse

    NASA Astrophysics Data System (ADS)

    Kavvada, Olga; Nelson, Kara L.; Horvath, Arpad

    2018-06-01

    Decentralization has the potential to reduce the scale of the piped distribution network needed to enable non-potable water reuse (NPR) in urban areas by producing recycled water closer to its point of use. However, tradeoffs exist between the economies of scale of treatment facilities and the size of the conveyance infrastructure, including energy for upgradient distribution of recycled water. To adequately capture the impacts from distribution pipes and pumping requirements, site-specific conditions must be accounted for. In this study, a generalized framework (a heuristic modeling approach using geospatial algorithms) is developed that estimates the financial cost, the energy use, and the greenhouse gas emissions associated with NPR (for toilet flushing) as a function of scale of treatment and conveyance networks with the goal of determining the optimal degree of decentralization. A decision-support platform is developed to assess and visualize NPR system designs considering topography, economies of scale, and building size. The platform can be used for scenario development to explore the optimal system size based on the layout of current or new buildings. The model also promotes technology innovation by facilitating the systems-level comparison of options to lower costs, improve energy efficiency, and lower greenhouse gas emissions.

  8. Assessment of erosion and sedimentation dynamic in a combined sewer network using online turbidity monitoring.

    PubMed

    Bersinger, T; Le Hécho, I; Bareille, G; Pigot, T

    2015-01-01

    Eroded sewer sediments are a significant source of organic matter discharge by combined sewer overflows. Many authors have studied the erosion and sedimentation processes at the scale of a section of sewer pipe and over short time periods. The objective of this study was to assess these processes at the scale of an entire sewer network and over 1 month, to understand whether phenomena observed on a small scale of space and time are still valid on a larger scale. To achieve this objective the continuous monitoring of turbidity was used. First, the study of successive rain events allows observation of the reduction of the available sediment and highlights the widely different erosion resistance for the different sediment layers. Secondly, calculation of daily chemical oxygen demand (COD) fluxes during the entire month was performed showing that sediment storage in the sewer pipe after a rain period is important and stops after 5 days. Nevertheless, during rainfall events, the eroded fluxes are more important than the whole sewer sediment accumulated during a dry weather period. This means that the COD fluxes promoted by runoff are substantial. This work confirms, with online monitoring, most of the conclusions from other studies on a smaller scale.

  9. Polymeric and composite materials for use in systems utilizing hot, flowing geothermal brine. II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lorensen, L.E.; Walkup, C.M.

    1978-04-13

    Further progress is reported on a continuing experimental program designed to select high-performance polymeric materials for use in geothermal power plants. In field tests 12 nozzles, 27 wear plates, and 2 types of polymer lined pipe were tested. Nozzles made of Teflons TFE and PFA, Tefzel, Ryton PPS and H-Resin/carbon cloth were little changed except for some scaling. The fluorocarbons scaled least rapidly. All blade type wear plates eroded, those based on Tefzel, PPQ, and PPS the least. Fluorocarbon lined pipes were little affected by exposure. In laboratory tests samples were heated at 250 and 300/sup 0/C in brine. Severalmore » materials including fluorocarbon and unhydrolyzable aromatic or cross-linked aliphatic, thermally stable polymers survived for periods up to 1300 h. In erosion tests, coatings based on epoxy resins and a fluorocarbon were most resistant; good adhesion was required.« less

  10. Lead poisoning prevention for preschool settings: a program template.

    PubMed

    Saatciler, Eda

    2015-01-01

    Lead is a naturally occurring metal that has been linked to neurological impairments and insanity since ancient times. It has been used in many products such as paint, pipes, and ceramics and still remains a public hazard. Young children between the ages of 6 months and 6 years with lead-contaminated housing are at the greatest risk for cognitive, neurological, and behavioral health problems. Briefly, lead exposure is around us and it correlates with learning deficits and violent behaviors as these children become adults. It also can cause anemia, abdominal pain, seizure, and death.

  11. Evaluating Heat Pipe Performance in 1/6 g Acceleration: Problems and Prospects

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; McCollum, Timothy A.; Gibson, Marc A.; Sanzi, James L.; Sechkar, Edward A.

    2011-01-01

    Heat pipes composed of titanium and water are being considered for use in the heat rejection system of a fission power system option for lunar exploration. Placed vertically on the lunar surface, the heat pipes would operate as thermosyphons in the 1/6 g environment. The design of thermosyphons for such an application is determined, in part, by the flooding limit. Flooding is composed of two components, the thickness of the fluid film on the walls of the thermosyphon and the interaction of the fluid flow with the concurrent vapor counter flow. Both the fluid thickness contribution and interfacial shear contribution are inversely proportional to gravity. Hence, evaluating the performance of a thermosyphon in a 1 g environment on Earth may inadvertently lead to overestimating the performance of the same thermosyphon as experienced in the 1/6 g environment on the moon. Several concepts of varying complexity have been proposed for evaluating thermosyphon performance in reduced gravity, ranging from tilting the thermosyphons on Earth based on a cosine function, to flying heat pipes on a low-g aircraft. This paper summarizes the problems and prospects for evaluating thermosyphon performance in 1/6 g.

  12. Flow accelerated corrosion of carbon steel feeder pipes from pressurized heavy water reactors

    NASA Astrophysics Data System (ADS)

    Singh, J. L.; Kumar, Umesh; Kumawat, N.; Kumar, Sunil; Kain, Vivekanand; Anantharaman, S.; Sinha, A. K.

    2012-10-01

    Detailed investigation of a number of feeder pipes received from Rajasthan Atomic Power Station Unit 2 (RAPS#2) after en-masse feeder pipe replacement after 15.67 Effective Full Power Years (EFPYs) was carried out. Investigations included ultrasonic thickness measurement by ultrasonic testing, optical microscopy, scanning electron microscopy, chemical analysis and X-ray Diffraction (XRD). Results showed that maximum thickness reduction of the feeder had occurred downstream and close to the weld in 32 NB (1.25″/32.75 mm ID) elbows. Rate of Flow Accelerated Corrosion (FAC) was measured to be higher in the lower diameter feeder pipes due to high flow velocity and turbulence. Weld regions had thinned to a lower extent than the parent material due to higher chromium content in the weld. A weld protrusion has been shown to add to the thinning due to FAC and lead to faster thinning rate at localized regions. Surface morphology of inner surface of feeder had shown different size scallop pattern over the weld and parent material. Inter-granular cracks were also observed along the weld fusion line and in the parent material in 32 NB outlet feeder elbow.

  13. Abrasive wear of Hilong BoTN hardfacings

    NASA Astrophysics Data System (ADS)

    Fedorova, L.; Fedorov, S.; Sadovnikov, A.; Ivanova, Y.; Voronina, M.

    2018-02-01

    The spread of steels, which are used to produce locks of steel drill pipes, adversely affects their wear resistance, which, in combination with low hardness of HV 2400 ... 2800 MPa as well as of the thread of screw, results in low wear resistance and the need for their reconstruction at the pipe control shop. An efficient way of improving the quality of drill pipe jonts is to hard-face them by the outside diameter with wear-resistant materials (hardbanding). One of the companies engaged in the development of hardfacing materials and hardbanding is Hilong (China) with weld seams of the brand BoTn. According to the results of the studies the following conclusion can be made: hardfacing increases the durability of the hardware, contributing to an increase in wear resistance of locks of DP under the conditions of abrasive action of aggressive geological formations; the usage of DP without wear-resistant weld seams is impermissible, because their further operation, as part of the drill-stem, can lead to emergency consequences; application of the pipes with the hardfacing collars together with the collars without hardfacing, due to varying degree of wear of jonts in the drill-stem, is also impermissible.

  14. Microbiological corrosion of ASTM SA105 carbon steel pipe for industrial fire water usage

    NASA Astrophysics Data System (ADS)

    Chidambaram, S.; Ashok, K.; Karthik, V.; Venkatakrishnan, P. G.

    2018-02-01

    The large number of metallic systems developed for last few decades against both general uniform corrosion and localized corrosion. Among all microbiological induced corrosion (MIC) is attractive, multidisciplinary and complex in nature. Many chemical processing industries utilizes fresh water for fire service to nullify major/minor fire. One such fire water service line pipe attacked by micro-organisms leads to leakage which is industrially important from safety point of view. Also large numbers of leakage reported in similar fire water service of nearby food processing plant, paper & pulp plant, steel plant, electricity board etc…In present investigation one such industrial fire water service line failure analysis of carbon steel line pipe was analyzed to determine the cause of failure. The water sample subjected to various chemical and bacterial analyses. Turbidity, pH, calcium hardness, free chlorine, oxidation reduction potential, fungi, yeasts, sulphide reducing bacteria (SRB) and total bacteria (TB) were measured on water sample analysis. The corrosion rate was measured on steel samples and corrosion coupon measurements were installed in fire water for validating non flow assisted localized corrosion. The sulphide reducing bacteria (SRB) presents in fire water causes a localized micro biological corrosion attack of line pipe.

  15. 40. EXTERIOR VIEW, BERK SWITCH TOWER, SOUTH NORWALK, SHOWING FRONT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. EXTERIOR VIEW, BERK SWITCH TOWER, SOUTH NORWALK, SHOWING FRONT ELEVATION AND PIPES LEADING TO SWITCHES - New York, New Haven & Hartford Railroad, Automatic Signalization System, Long Island Sound shoreline between Stamford & New Haven, Stamford, Fairfield County, CT

  16. 45. EXTERIOR VIEW, GREEN SWITCH TOLWER, COS COB, SHOWING BARS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. EXTERIOR VIEW, GREEN SWITCH TOLWER, COS COB, SHOWING BARS AND PIPES LEADING TO SWITCHES - New York, New Haven & Hartford Railroad, Automatic Signalization System, Long Island Sound shoreline between Stamford & New Haven, Stamford, Fairfield County, CT

  17. EVALUATING THE IMPACT OF WATER CHEMISTRY ON CUPROSOLVENCY AND COPPER CORROSION BY-PRODUCT USING A SIMPLE COPPER PIPE RECIRCULATING LOOP SYSTEM

    EPA Science Inventory

    1991, EPA publicized the Lead and Copper Rule (LCR),which set regulations to minimize the amount of lead copper in drinking water. The LCR set the copper action level at 1.3 mg/L in more then 10% of customer’s first-draw taps sampled. Potential health effects of copper include vo...

  18. Detection and characterisation of anthropogenic pieces by magnetic method

    NASA Astrophysics Data System (ADS)

    Nodot, Emilie; Munschy, Marc; Benevent, Pierre

    2013-04-01

    Human activities have let many anthropogenic objects buried under our feet. Some of these like explosive devices left after the World Wars turn out to be a threat to safety or environment. Others must be perfectly localised in case of construction work, for example gas pipe. Geophysics and more specifically magnetic cartography (many of these items are magnetic) can obviously help to locate them. We already use this method on daily basis to detect UXO (unexploded ordnance) but less than 10% of the unearthed objects are actually bombs or shells. Detection and mostly characterisation methods must be improved in order to reduce this proportion. On the field there are a few things we can do to increase data qualities. Characterisation may be improved by multiple scale prospections. We search a large area with our usual and rather fast method then we achieve high definition cartographies of small interesting areas (upon the object to characterise). In the case of measurements in an urban environment for example, data are distorted. The traffic (train, tramway, cars…) produces temporal variations of the magnetic field. This effect can be lessened, sometimes even removed by the use of a fixed scalar magnetic sensor. Data treatment is another key as regards the characterisation. Tools such as analytic signal or derivative are frequently used at the first degree. We will see that in a synthetic case the second and third degree bring even more information. A new issue appeared recently about pipes. Can we localise very precisely (less than 10 cm uncertainty) a gas pipe? Horizontally we can but due to our inversion method we still have troubles with the depth accuracy. Our final concern is about the amplitude of some anomalies. Potential methods equations are based on the fact that the anomaly norm must be minor to magnetic field norm. Sometimes this is not the case but vector magnetometry is a lead to solve this problem.

  19. Hydraulic trade-offs and space filling enable better predictions of vascular structure and function in plants

    PubMed Central

    Savage, V. M.; Bentley, L. P.; Enquist, B. J.; Sperry, J. S.; Smith, D. D.; Reich, P. B.; von Allmen, E. I.

    2010-01-01

    Plant vascular networks are central to botanical form, function, and diversity. Here, we develop a theory for plant network scaling that is based on optimal space filling by the vascular system along with trade-offs between hydraulic safety and efficiency. Including these evolutionary drivers leads to predictions for sap flow, the taper of the radii of xylem conduits from trunk to terminal twig, and how the frequency of xylem conduits varies with conduit radius. To test our predictions, we use comprehensive empirical measurements of maple, oak, and pine trees and complementary literature data that we obtained for a wide range of tree species. This robust intra- and interspecific assessment of our botanical network model indicates that the central tendency of observed scaling properties supports our predictions much better than the West, Brown, and Enquist (WBE) or pipe models. Consequently, our model is a more accurate description of vascular architecture than what is given by existing network models and should be used as a baseline to understand and to predict the scaling of individual plants to whole forests. In addition, our model is flexible enough to allow the quantification of species variation around rules for network design. These results suggest that the evolutionary drivers that we propose have been fundamental in determining how physiological processes scale within and across plant species. PMID:21149696

  20. Hydraulic trade-offs and space filling enable better predictions of vascular structure and function in plants.

    PubMed

    Savage, V M; Bentley, L P; Enquist, B J; Sperry, J S; Smith, D D; Reich, P B; von Allmen, E I

    2010-12-28

    Plant vascular networks are central to botanical form, function, and diversity. Here, we develop a theory for plant network scaling that is based on optimal space filling by the vascular system along with trade-offs between hydraulic safety and efficiency. Including these evolutionary drivers leads to predictions for sap flow, the taper of the radii of xylem conduits from trunk to terminal twig, and how the frequency of xylem conduits varies with conduit radius. To test our predictions, we use comprehensive empirical measurements of maple, oak, and pine trees and complementary literature data that we obtained for a wide range of tree species. This robust intra- and interspecific assessment of our botanical network model indicates that the central tendency of observed scaling properties supports our predictions much better than the West, Brown, and Enquist (WBE) or pipe models. Consequently, our model is a more accurate description of vascular architecture than what is given by existing network models and should be used as a baseline to understand and to predict the scaling of individual plants to whole forests. In addition, our model is flexible enough to allow the quantification of species variation around rules for network design. These results suggest that the evolutionary drivers that we propose have been fundamental in determining how physiological processes scale within and across plant species.

  1. Corrosion and scaling potential in drinking water distribution system of tabriz, northwestern iran.

    PubMed

    Taghipour, Hassan; Shakerkhatibi, Mohammad; Pourakbar, Mojtaba; Belvasi, Mehdi

    2012-01-01

    This paper discusses the corrosion and scaling potential of Tabriz drinking water distribution system in Northwest of Iran. Internal corrosion of piping is a serious problem in drinking water industry. Corrosive water can cause intrusion of heavy metals especially lead in to water, therefore effecting public health. The aim of this study was to determine corrosion and scaling potential in potable water distribution system of Tabriz during the spring and summer in 2011. This study was carried out using Langlier Saturation Index, Ryznar Stability Index, Puckorius Scaling Index, and Aggressiveness indices. Eighty samples were taken from all over the city within two seasons, spring, and summer. Related parameters including temperature, pH, total dissolved solids, calcium hardness, and total alkalinity in all samples were measured in laboratory according to standard method manual. For the statistical analysis of the results, SPSS software (version 11.5) was used The mean and standard deviation values of Langlier, Ryznar, Puckorius and Aggressiveness Indices were equal to -0.68 (±0.43), 8.43 (±0.55), 7.86 (±0.36) and 11.23 (±0.43), respectively. By survey of corrosion indices, it was found that Tabriz drinking water is corrosive. In order to corrosion control, it is suggested that laboratorial study with regard to the distribution system condition be carried out to adjust effective parameters such as pH.

  2. Chlorine decay and bacterial inactivation kinetics in drinking water in the tropics.

    PubMed

    Thøgersen, J; Dahi, E

    1996-09-01

    The decay of free chlorine (Cl2) and combined chlorine (mostly monochloramine: NH2Cl) and the inactivation of bacteria was examined in Dar es Salaam, Tanzania. Batch experiments, pilot-scale pipe experiments and full-scale pipe experiments were carried out to establish the kinetics for both decay and inactivation, and to compare the two disinfectants for use under tropical conditions. The decay of both disinfectants closely followed first order kinetics, with respect to the concentration of both disinfectant and disinfectant-consuming substances. Bacterial densities exhibited a kinetic pattern consisting of first order inactivation with respect to the density of the bacteria and the concentration of the disinfectant, and first order growth with respect to the bacterial density. The disinfection kinetic model takes the decaying concentration of the disinfectant into account. The decay rate constant for free chlorine was 114 lg(-1)h(-1), while the decay rate constant for combined chlorine was 1.84 lg(-1)h(-1) (1.6% of the decay rate for free chlorine). The average concentration of disinfectant consuming substances in the water phase was 2.6 mg Cl2/l for free chlorine and 5.6 mg NH2Cl/l for combined chlorine. The decay rate constant and the concentration of disinfectant consuming substances when water was pumped through pipes, depended on whether or not chlorination was continuous. Combined chlorine especially could clean the pipes of disinfectant consuming substances. The inactivation rate constant λ, was estimated at 3.06×10(4) lg(-1)h(-1). Based on the inactivation rate constant, and a growth rate constant determined in a previous study, the critical concentration of free chlorine was found to be 0.08 mg Cl2/l. The critical concentration is a value below which growth rates dominate over inactivation.

  3. Factors affecting economies of scale in combined sewer systems.

    PubMed

    Maurer, Max; Wolfram, Martin; Anja, Herlyn

    2010-01-01

    A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.

  4. Kimberlite Wall Rock Fragmentation: Venetia K08 Pipe Development

    NASA Astrophysics Data System (ADS)

    Barnett, W.; Kurszlaukis, S.; Tait, M.; Dirks, P.

    2009-05-01

    Volcanic systems impose powerful disrupting forces on the country rock into which they intrude. The nature of the induced brittle deformation or fragmentation can be characteristic of the volcanic processes ongoing within the volcanic system, but are most typically partially removed or obscured by repeated, overprinting volcanic activity in mature pipes. Incompletely evolved pipes may therefore provide important evidence for the types and stages of wall rock fragmentation, and mechanical processes responsible for the fragmentation. Evidence for preserved stages of fragmentation is presented from a detailed study of the K08 pipe within the Cambrian Venetia kimberlite cluster, South Africa. This paper investigates the growth history of the K08 pipe and the mechanics of pipe development based on observations in the pit, drill core and thin sections, from geochemical analyses, particle size distribution analyses, and 3D modeling. Present open pit exposures of the K08 pipe comprise greater than 90% mega-breccia of country rock clasts (gneiss and schist) with <10% intruding, coherent kimberlite. Drill core shows that below about 225 m the CRB includes increasing quantities of kimberlite. The breccia clasts are angular, clast-supported with void or carbonate cement between the clasts. Average clast sizes define sub-horizontal layers tens of metres thick across the pipe. Structural and textural observations indicate the presence of zones of re-fragmentation or zones of brittle shearing. Breccia textural studies and fractal statistics on particle size distributions (PSD) is used to quantify sheared and non- sheared breccia zones. The calculated energy required to form the non-sheared breccia PSD implies an explosive early stage of fragmentation that pre-conditions the rock mass. The pre-conditioning would have been caused by explosions that are either phreatic or phreatomagmatic in nature. The explosions are likely to have been centered on a dyke, or pulses of preceding volatile-fluid phases, which have encountered a local hydrologically active fault. The explosions were inadequate in mechanical energy release (72% of a mine production blast) to eject material from the pipe, and the pipe may not have breached surface. The next stage of fragmentation is interpreted to have been an upward-moving collapse of the pre-conditioned hanging wall of a subterranean volcanic excavation. This would explain the mega-scale layering across the width of the breccia pipe. It must be questioned whether the preserved K08 architecture represents early pipe development in general, or is a special case of a late pipe geometry modification process. Previous literature describes sidewall and hanging wall caving processes elsewhere in the Venetia cluster and other kimberlites world wide. A requirement for emplacement models that include upward pipe growth processes is the availability of space (mass deficit at depth) into which the caving and/or dilating breccia can expand. It is possible that K08 might be connected to adjacent K02 at a depth somewhere below 400m, which would explain the presence of volcaniclastic kimberlite at depth within the K08 pipe. K08 is likely an incomplete ancillary sideward development to K02. The latest stage of brecciation is quantified through an observed evolution in the fractal dimension of the PSD. It is interpreted to be due to complex adjustments in volume in the pipe causing shearing and re-fragmentation of the breccia.

  5. Thermochemical Processes | Bioenergy | NREL

    Science.gov Websites

    model catalysts appear on a montage of images of wood chips, liquid gasoline, a gas tanker truck, and a , pipes, and hoses, pouring a liquid from a large hose into a bucket. Integration, Scale-Up, and Piloting

  6. 45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), VIEW LOOKING EAST. LEAD ENCLOSED PIPING IS DRAIN FROM BOILER CHAMBER No. 1 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  7. 44. EXTERIOR VIEW, GREEN SWITCH TOWER, COS COB, SHOWING BARS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. EXTERIOR VIEW, GREEN SWITCH TOWER, COS COB, SHOWING BARS LINKING SWITCH LEVERS AND PIPES LEADING TO SWITCHES - New York, New Haven & Hartford Railroad, Automatic Signalization System, Long Island Sound shoreline between Stamford & New Haven, Stamford, Fairfield County, CT

  8. LEAD CORROSION SUPPORT FOR STATES AND REGIONS

    EPA Science Inventory

    This poster provides a summary of some of the collaborative research and applications to solving treatment and regulatory compliance done by TTEB. The poster describes the analytical methodology applied to the pipe specimens from Washington DC, and the inferences about causes of...

  9. Metallurgical causes for the occurrence of creep damage in longitudinally seam-welded Cr-Mo high-energy piping

    NASA Astrophysics Data System (ADS)

    Zhou, Gang

    A continuous occurrence of catastrophic failures, leaks and cracks of the Cr-Mo steam piping has created widespread utility concern for the integrity and serviceability of the seam-welded piping systems in power plants across USA. Cr-Mo steels are the materials widely used for elevated temperature service in fossil-fired generating stations. A large percentage of the power plant units with the Cr-Mo seam-welded steam piping have been in operation for a long duration such that the critical components of the units have been employed beyond the design life (30 or 40 years). This percentage will increase even more significantly in the near future. There is a strong desire to extend and thus there is a need to assess the remaining life of these units. Thus, understanding of the metallurgical causes for the failures and damage in the Cr-Mo seam-welded piping plays a major role in estimating possible life-extension and decision making on whether to operate, repair or replace. In this study, an optical metallographic method and a Cryo-Crack fractographic method have been developed for characterization and quantification of the damage in seam-welded steam piping. More than 500 metallographic assessments, from more than 25 power plants, have been accomplished using the optical metallographic method, and more than 200 fractographic specimens from 10 power plants have been evaluated using the "Cryo-Crack" fractographic technique. For comparison, "virgin" SA welds were fabricated using the Mohave welding procedure with re-N&T Mohave base metal with both "acid" and "basic" fluxes. The damage mechanism, damage distribution pattern, damage classification, correlation of the damage with the microstructural features of these SA welds and the impurity segregation patterns have been determined. A physical model for cavitation (leading to failure) in Cr-Mo SA weld metals and evaluation methodologies for high energy piping are proposed.

  10. Effect of preliminary thermal treatment on decomposition kinetics of austenite in low-alloyed pipe steel in intercritical temperature interval

    NASA Astrophysics Data System (ADS)

    Makovetskii, A. N.; Tabatchikova, T. I.; Yakovleva, I. L.; Tereshchenko, N. A.; Mirzaev, D. A.

    2013-06-01

    The decomposition kinetics of austenite that appears in the 13KhFA low-alloyed pipe steel upon heating the samples in an intercritical temperature interval (ICI) and exposure for 5 or 30 min has been studied by the method of high-speed dilatometry. The results of dilatometry are supplemented by the microstructure analysis. Thermokinetic diagrams of the decomposition of the γ phase are represented. The conclusion has been drawn that an increase in the duration of exposure in the intercritical interval leads to a significant increase in the stability of the γ phase.

  11. The visual and radiological inspection of a pipeline using a teleoperated pipe crawler

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fogle, R.F.; Kuelske, K.; Kellner, R.A.

    1996-07-01

    In the 1950s the Savannah River Site built an open, unlined retention basin for temporary storage of potentially radionuclide-contaminated cooling water form a chemical separations process and storm water drainage from a nearby waste management facility which stored large quantities of nuclear fission by-products in carbon steel tanks. An underground process pipeline lead to the basin. Once the closure of the basin in 1972, further assessment has been required. A visual and radiological inspection of the pipeline was necessary to aid in the decision about further remediation. This article describes the inspection using a teleoperated pipe crawler. 5 figs.

  12. Solar energy collection system

    NASA Technical Reports Server (NTRS)

    Miller, C. G.; Stephens, J. B. (Inventor)

    1979-01-01

    A fixed, linear, ground-based primary reflector having an extended curved sawtooth-contoured surface covered with a metalized polymeric reflecting material, reflects solar energy to a movably supported collector that is kept at the concentrated line focus reflector primary. The primary reflector may be constructed by a process utilizing well known freeway paving machinery. The solar energy absorber is preferably a fluid transporting pipe. Efficient utilization leading to high temperatures from the reflected solar energy is obtained by cylindrical shaped secondary reflectors that direct off-angle energy to the absorber pipe. A seriatim arrangement of cylindrical secondary reflector stages and spot-forming reflector stages produces a high temperature solar energy collection system of greater efficiency.

  13. Formation of carbonate pipes in the northern Okinawa Trough linked to strong sulfate exhaustion and iron supply

    NASA Astrophysics Data System (ADS)

    Peng, Xiaotong; Guo, Zixiao; Chen, Shun; Sun, Zhilei; Xu, Hengchao; Ta, Kaiwen; Zhang, Jianchao; Zhang, Lijuan; Li, Jiwei; Du, Mengran

    2017-05-01

    The microbial anaerobic oxidation of methane (AOM), a key biogeochemical process that consumes substantial amounts of methane produced in seafloor sediments, can lead to the formation of carbonate deposits at or beneath the sea floor. Although Fe oxide-driven AOM has been identified in cold seep sediments, the exact mode by which it may influence the formation of carbonate deposits remains poorly understood. Here, we characterize the morphology, petrology and geochemistry of a methane-derived Fe-rich carbonate pipe in the northern Okinawa Trough (OT). We detect abundant authigenic pyrites, as well as widespread trace Fe, within microbial mat-like carbonate veins in the pipe. The in situ δ34S values of these pyrites range from -3.9 to 31.6‰ (VCDT), suggesting a strong consumption of seawater sulfate by sulfate-driven AOM at the bottom of sulfate reduction zone. The positive δ56Fe values of pyrite and notable enrichment of Fe in the OT pipe concurrently indicate that the pyrites are primarily derived from Fe oxides in deep sediments. We propose that the Fe-rich carbonate pipe formed at the bottom of sulfate reduction zone, below which Fe-driven AOM, rather than Fe-oxide reduction coupled to organic matter degradation, might be responsible for the abundantly available Fe2+ in the fluids from which pyrites precipitated. The Fe-rich carbonate pipe described in this study probably represents the first fossil example of carbonate deposits linked to Fe-driven AOM. Because Fe-rich carbonate deposits have also been found at other cold seeps worldwide, we infer that similar processes may play an essential role in biogeochemical cycling of sub-seafloor methane and Fe at continental margins.

  14. Stochastic analysis of uncertain thermal parameters for random thermal regime of frozen soil around a single freezing pipe

    NASA Astrophysics Data System (ADS)

    Wang, Tao; Zhou, Guoqing; Wang, Jianzhou; Zhou, Lei

    2018-03-01

    The artificial ground freezing method (AGF) is widely used in civil and mining engineering, and the thermal regime of frozen soil around the freezing pipe affects the safety of design and construction. The thermal parameters can be truly random due to heterogeneity of the soil properties, which lead to the randomness of thermal regime of frozen soil around the freezing pipe. The purpose of this paper is to study the one-dimensional (1D) random thermal regime problem on the basis of a stochastic analysis model and the Monte Carlo (MC) method. Considering the uncertain thermal parameters of frozen soil as random variables, stochastic processes and random fields, the corresponding stochastic thermal regime of frozen soil around a single freezing pipe are obtained and analyzed. Taking the variability of each stochastic parameter into account individually, the influences of each stochastic thermal parameter on stochastic thermal regime are investigated. The results show that the mean temperatures of frozen soil around the single freezing pipe with three analogy method are the same while the standard deviations are different. The distributions of standard deviation have a great difference at different radial coordinate location and the larger standard deviations are mainly at the phase change area. The computed data with random variable method and stochastic process method have a great difference from the measured data while the computed data with random field method well agree with the measured data. Each uncertain thermal parameter has a different effect on the standard deviation of frozen soil temperature around the single freezing pipe. These results can provide a theoretical basis for the design and construction of AGF.

  15. Inverse heat conduction estimation of inner wall temperature fluctuations under turbulent penetration

    NASA Astrophysics Data System (ADS)

    Guo, Zhouchao; Lu, Tao; Liu, Bo

    2017-04-01

    Turbulent penetration can occur when hot and cold fluids mix in a horizontal T-junction pipe at nuclear plants. Caused by the unstable turbulent penetration, temperature fluctuations with large amplitude and high frequency can lead to time-varying wall thermal stress and even thermal fatigue on the inner wall. Numerous cases, however, exist where inner wall temperatures cannot be measured and only outer wall temperature measurements are feasible. Therefore, it is one of the popular research areas in nuclear science and engineering to estimate temperature fluctuations on the inner wall from measurements of outer wall temperatures without damaging the structure of the pipe. In this study, both the one-dimensional (1D) and the two-dimensional (2D) inverse heat conduction problem (IHCP) were solved to estimate the temperature fluctuations on the inner wall. First, numerical models of both the 1D and the 2D direct heat conduction problem (DHCP) were structured in MATLAB, based on the finite difference method with an implicit scheme. Second, both the 1D IHCP and the 2D IHCP were solved by the steepest descent method (SDM), and the DHCP results of temperatures on the outer wall were used to estimate the temperature fluctuations on the inner wall. Third, we compared the temperature fluctuations on the inner wall estimated by the 1D IHCP with those estimated by the 2D IHCP in four cases: (1) when the maximum disturbance of temperature of fluid inside the pipe was 3°C, (2) when the maximum disturbance of temperature of fluid inside the pipe was 30°C, (3) when the maximum disturbance of temperature of fluid inside the pipe was 160°C, and (4) when the fluid temperatures inside the pipe were random from 50°C to 210°C.

  16. Steel Fibers Reinforced Concrete Pipes - Experimental Tests and Numerical Simulation

    NASA Astrophysics Data System (ADS)

    Doru, Zdrenghea

    2017-10-01

    The paper presents in the first part a state of the art review of reinforced concrete pipes used in micro tunnelling realised through pipes jacking method and design methods for steel fibres reinforced concrete. In part two experimental tests are presented on inner pipes with diameters of 1410mm and 2200mm, and specimens (100x100x500mm) of reinforced concrete with metal fibres (35 kg / m3). In part two experimental tests are presented on pipes with inner diameters of 1410mm and 2200mm, and specimens (100x100x500mm) of reinforced concrete with steel fibres (35 kg / m3). The results obtained are analysed and are calculated residual flexural tensile strengths which characterise the post-cracking behaviour of steel fibres reinforced concrete. In the third part are presented numerical simulations of the tests of pipes and specimens. The model adopted for the pipes test was a three-dimensional model and loads considered were those obtained in experimental tests at reaching breaking forces. Tensile stresses determined were compared with mean flexural tensile strength. To validate tensile parameters of steel fibres reinforced concrete, experimental tests of the specimens were modelled with MIDAS program to reproduce the flexural breaking behaviour. To simulate post - cracking behaviour was used the method σ — ε based on the relationship stress - strain, according to RILEM TC 162-TDF. For the specimens tested were plotted F — δ diagrams, which have been superimposed for comparison with the similar diagrams of experimental tests. The comparison of experimental results with those obtained from numerical simulation leads to the following conclusions: - the maximum forces obtained by numerical calculation have higher values than the experimental values for the same tensile stresses; - forces corresponding of residual strengths have very similar values between the experimental and numerical calculations; - generally the numerical model estimates a breaking force greater than that obtained in the experimental tests. Experimental and numerical studies are used to establish the residual characteristic flexural tensile strength minimum guaranteed and limits of applicability of concrete pipes reinforced with steel fibres used in various field and loading situations.

  17. Trajectory and Mixing Scaling Laws for Confined and Unconfined Transverse Jets

    DTIC Science & Technology

    2012-05-01

    engines , issues of confinement, very large density ratio, and super/transcritical effects complicate the utility of the ...opposite wall at a streamwise position that is one -half pipe diameter downstream of the injection location (termed moderate impaction). This...BD, and Eq. 10 scaling laws are 0.97 and 0.90, respectively. One of the primary effects of the confinement is that the

  18. Experience with the design and start up of two full-scale UASB plants in Brazil: enhancements and drawbacks.

    PubMed

    Chernicharo, C A L; Almeida, P G S; Lobato, L C S; Couto, T C; Borges, J M; Lacerda, Y S

    2009-01-01

    This paper discusses the main drawbacks and enhancements experienced with the design and start up of two full-scale UASB plants in Brazil. The topics addressed are related to blockage of inlet pipes, scum accumulation, seed sludge for the start-up, corrosion and gas leakage, odour generation and sludge management. The paper describes the main improvements achieved.

  19. Austenite Grain Size Control in Upstream Processing of Niobium Microalloyed Steels by Nano-Scale Precipitate Engineering of TiN-NbC Composite

    NASA Astrophysics Data System (ADS)

    Subramanian, S. V.; Ma, Xiaoping; Rehman, Kashif

    There is a growing demand for thicker gage pipes particularly for off-shore projects. Austenite grain size control in upstream processing before pancaking is essential to obtain excellent DBTT and DWTT properties in thicker gage product. This paper examines the basic science aspects of austenite grain size control by nano-scale precipitate engineering.

  20. ADAPTION OF NONSTANDARD PIPING COMPONENTS INTO PRESENT DAY SEISMIC CODES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    D. T. Clark; M. J. Russell; R. E. Spears

    2009-07-01

    With spiraling energy demand and flat energy supply, there is a need to extend the life of older nuclear reactors. This sometimes requires that existing systems be evaluated to present day seismic codes. Older reactors built in the 1960s and early 1970s often used fabricated piping components that were code compliant during their initial construction time period, but are outside the standard parameters of present-day piping codes. There are several approaches available to the analyst in evaluating these non-standard components to modern codes. The simplest approach is to use the flexibility factors and stress indices for similar standard components withmore » the assumption that the non-standard component’s flexibility factors and stress indices will be very similar. This approach can require significant engineering judgment. A more rational approach available in Section III of the ASME Boiler and Pressure Vessel Code, which is the subject of this paper, involves calculation of flexibility factors using finite element analysis of the non-standard component. Such analysis allows modeling of geometric and material nonlinearities. Flexibility factors based on these analyses are sensitive to the load magnitudes used in their calculation, load magnitudes that need to be consistent with those produced by the linear system analyses where the flexibility factors are applied. This can lead to iteration, since the magnitude of the loads produced by the linear system analysis depend on the magnitude of the flexibility factors. After the loading applied to the nonstandard component finite element model has been matched to loads produced by the associated linear system model, the component finite element model can then be used to evaluate the performance of the component under the loads with the nonlinear analysis provisions of the Code, should the load levels lead to calculated stresses in excess of Allowable stresses. This paper details the application of component-level finite element modeling to account for geometric and material nonlinear component behavior in a linear elastic piping system model. Note that this technique can be applied to the analysis of B31 piping systems.« less

  1. Conduction-driven cooling of LED-based automotive LED lighting systems for abating local hot spots

    NASA Astrophysics Data System (ADS)

    Saati, Ferina; Arik, Mehmet

    2018-02-01

    Light-emitting diode (LED)-based automotive lighting systems pose unique challenges, such as dual-side packaging (front side for LEDs and back side for driver electronics circuit), size, harsh ambient, and cooling. Packaging for automotive lighting applications combining the advanced printed circuit board (PCB) technology with a multifunctional LED-based board is investigated with a focus on the effect of thermal conduction-based cooling for hot spot abatement. A baseline study with a flame retardant 4 technology, commonly known as FR4 PCB, is first compared with a metal-core PCB technology, both experimentally and computationally. The double-sided advanced PCB that houses both electronics and LEDs is then investigated computationally and experimentally compared with the baseline FR4 PCB. Computational models are first developed with a commercial computational fluid dynamics software and are followed by an advanced PCB technology based on embedded heat pipes, which is computationally and experimentally studied. Then, attention is turned to studying different heat pipe orientations and heat pipe placements on the board. Results show that conventional FR4-based light engines experience local hot spots (ΔT>50°C) while advanced PCB technology based on heat pipes and thermal spreaders eliminates these local hot spots (ΔT<10°C), leading to a higher lumen extraction with improved reliability. Finally, possible design options are presented with embedded heat pipe structures that further improve the PCB performance.

  2. Efficient prediction of human protein-protein interactions at a global scale.

    PubMed

    Schoenrock, Andrew; Samanfar, Bahram; Pitre, Sylvain; Hooshyar, Mohsen; Jin, Ke; Phillips, Charles A; Wang, Hui; Phanse, Sadhna; Omidi, Katayoun; Gui, Yuan; Alamgir, Md; Wong, Alex; Barrenäs, Fredrik; Babu, Mohan; Benson, Mikael; Langston, Michael A; Green, James R; Dehne, Frank; Golshani, Ashkan

    2014-12-10

    Our knowledge of global protein-protein interaction (PPI) networks in complex organisms such as humans is hindered by technical limitations of current methods. On the basis of short co-occurring polypeptide regions, we developed a tool called MP-PIPE capable of predicting a global human PPI network within 3 months. With a recall of 23% at a precision of 82.1%, we predicted 172,132 putative PPIs. We demonstrate the usefulness of these predictions through a range of experiments. The speed and accuracy associated with MP-PIPE can make this a potential tool to study individual human PPI networks (from genomic sequences alone) for personalized medicine.

  3. Mechanical Expansion of Steel Tubing as a Solution to Leaky Wellbores

    PubMed Central

    Radonjic, Mileva; Kupresan, Darko

    2014-01-01

    Wellbore cement, a procedural component of wellbore completion operations, primarily provides zonal isolation and mechanical support of the metal pipe (casing), and protects metal components from corrosive fluids. These are essential for uncompromised wellbore integrity. Cements can undergo multiple forms of failure, such as debonding at the cement/rock and cement/metal interfaces, fracturing, and defects within the cement matrix. Failures and defects within the cement will ultimately lead to fluid migration, resulting in inter-zonal fluid migration and premature well abandonment. Currently, there are over 1.8 million operating wells worldwide and over one third of these wells have leak related problems defined as Sustained Casing Pressure (SCP)1. The focus of this research was to develop an experimental setup at bench-scale to explore the effect of mechanical manipulation of wellbore casing-cement composite samples as a potential technology for the remediation of gas leaks. The experimental methodology utilized in this study enabled formation of an impermeable seal at the pipe/cement interface in a simulated wellbore system. Successful nitrogen gas flow-through measurements demonstrated that an existing microannulus was sealed at laboratory experimental conditions and fluid flow prevented by mechanical manipulation of the metal/cement composite sample. Furthermore, this methodology can be applied not only for the remediation of leaky wellbores, but also in plugging and abandonment procedures as well as wellbore completions technology, and potentially preventing negative impacts of wellbores on subsurface and surface environments. PMID:25490436

  4. Mechanical expansion of steel tubing as a solution to leaky wellbores.

    PubMed

    Radonjic, Mileva; Kupresan, Darko

    2014-11-20

    Wellbore cement, a procedural component of wellbore completion operations, primarily provides zonal isolation and mechanical support of the metal pipe (casing), and protects metal components from corrosive fluids. These are essential for uncompromised wellbore integrity. Cements can undergo multiple forms of failure, such as debonding at the cement/rock and cement/metal interfaces, fracturing, and defects within the cement matrix. Failures and defects within the cement will ultimately lead to fluid migration, resulting in inter-zonal fluid migration and premature well abandonment. Currently, there are over 1.8 million operating wells worldwide and over one third of these wells have leak related problems defined as Sustained Casing Pressure (SCP). The focus of this research was to develop an experimental setup at bench-scale to explore the effect of mechanical manipulation of wellbore casing-cement composite samples as a potential technology for the remediation of gas leaks. The experimental methodology utilized in this study enabled formation of an impermeable seal at the pipe/cement interface in a simulated wellbore system. Successful nitrogen gas flow-through measurements demonstrated that an existing microannulus was sealed at laboratory experimental conditions and fluid flow prevented by mechanical manipulation of the metal/cement composite sample. Furthermore, this methodology can be applied not only for the remediation of leaky wellbores, but also in plugging and abandonment procedures as well as wellbore completions technology, and potentially preventing negative impacts of wellbores on subsurface and surface environments.

  5. Bathyphotometer bioluminescence potential measurements: A framework for characterizing flow agitators and predicting flow-stimulated bioluminescence intensity

    NASA Astrophysics Data System (ADS)

    Latz, Michael I.; Rohr, Jim

    2013-07-01

    Bathyphotometer measurements of bioluminescence are used as a proxy for the abundance of luminescent organisms for studying population dynamics; the interaction of luminescent organisms with physical, chemical, and biological oceanographic processes; and spatial complexity especially in coastal areas. However, the usefulness of bioluminescence measurements has been limited by the inability to compare results from different bathyphotometer designs, or even the same bathyphotometer operating at different volume flow rates. The primary objective of this study was to compare measurements of stimulated bioluminescence of four species of cultured dinoflagellates, the most common source of bioluminescence in coastal waters, using two different bathyphotometer flow agitators as a function of bathyphotometer volume flow rate and dinoflagellate concentration. For both the NOSC and BIOLITE flow agitators and each species of dinoflagellate tested, there was a critical volume flow rate, above which average bioluminescence intensity, designated as bathyphotometer bioluminescence potential (BBP), remained relatively constant and scaled directly with dinoflagellate cell concentration. At supra-critical volume flow rates, the ratio of BIOLITE to NOSC BBP was nearly constant for the same species studied, but varied between species. The spatial pattern and residence time of flash trajectories within the NOSC flow agitator indicated the presence of dominant secondary recirculating flows, where most of the bioluminescence was detected. A secondary objective (appearing in the Appendix) was to study the feasibility of using NOSC BBP to scale flow-stimulated bioluminescence intensity across similar flow fields, where the contributing composition of luminescent species remained the same. Fully developed turbulent pipe flow was chosen because it is hydrodynamically well characterized. Average bioluminescence intensity in a 2.54-cm i.d. pipe was highly correlated with wall shear stress and BBP. This correlation, when further scaled by pipe diameter, effectively predicted bioluminescence intensity in fully developed turbulent flow in a 0.83-cm i.d. pipe. Determining similar correlations between other bathyphotometer flow agitators and flow fields will allow bioluminescence potential measurements to become a more powerful tool for the oceanographic community.

  6. Surface Features Parameterization and Equivalent Roughness Height Estimation of a Real Subglacial Conduit in the Arctic

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Liu, X.; Mankoff, K. D.; Gulley, J. D.

    2016-12-01

    The surfaces of subglacial conduits are very complex, coupling multi-scale roughness, large sinuosity, and cross-sectional variations together. Those features significantly affect the friction law and drainage efficiency inside the conduit by altering velocity and pressure distributions, thus posing considerable influences on the dynamic development of the conduit. Parameterizing the above surface features is a first step towards understanding their hydraulic influences. A Matlab package is developed to extract the roughness field, the conduit centerline, and associated area and curvature data from the conduit surface, acquired from 3D scanning. By using those data, the characteristic vertical and horizontal roughness scales are then estimated based on the structure functions. The centerline sinuosities, defined through three concepts, i.e., the traditional definition of a fluvial river, entropy-based sinuosity, and curvature-based sinuosity, are also calculated and compared. The cross-sectional area and equivalent circular diameter along the centerline are also calculated. Among those features, the roughness is especially important due to its pivotal role in determining the wall friction, and thus an estimation of the equivalent roughness height is of great importance. To achieve such a goal, the original conduit is firstly simplified into a straight smooth pipe with the same volume and centerline length, and the roughness field obtained above is then reconstructed into the simplified pipe. An OpenFOAM-based Large-eddy-simulation (LES) is then performed based on the reconstructed pipe. Considering that the Reynolds number is of the order 106, and the relative roughness is larger than 5% for 60% of the conduit, we test the validity of the resistance law for completely rough pipe. The friction factor is calculated based on the pressure drop and mean velocity in the simulation. Working together, the equivalent roughness height can be calculated. However, whether the assumption is applicable for the current case, i.e., high relative roughness, is a question. Two other roughness heights, i.e., the vertical roughness scale based on structure functions and viscous sublayer thickness determined from the wall boundary layer are also calculated and compared with the equivalent roughness height.

  7. Response of reinforced concrete and corrugated steel pipes to surface load

    NASA Astrophysics Data System (ADS)

    Lay, Geoff R.

    Full-scale simulated live load tests were conducted in a controlled laboratory setting using a single-axle frame on 600-mm-inner-diameter reinforced concrete pipe (RCP) and corrugated steel pipe (CSP) when buried in dense, well-graded sand and gravel. Measurements of the RCP at nominal and working forces and beyond are reported for 0.3, 0.6 and 0.9 m of soil cover above the pipe crown. The RCP experienced no cracking when buried at 0.3 m under nominal and working CL-625 and CL-800 single-axle design loads. At these loads, the vertical contraction of the pipe diameter was less than 0.08 and 0.10 mm and the largest tensile strains in the pipe were 75 and 100 muepsilon (50-60% of the cracking strain), respectively. A 0.15 (+/-0.05)-mm-wide axial crack developed at the inner crown in the presence of a 6 kNm/m circumferential bending moment (70% of the theoretical ultimate moment capacity) at the fully factored CL-625 load. This crack did not propagate or widen from 3 series of cyclic load-unload tests. At 1300 kN of applied load the change in pipe diameter was less than 3.5 mm. Increasing soil cover from 0.3 to 0.6 to 0.9 m reduced the circumferential crown bending moment from 6.0 to 3.9 to 2.1 kNm/m, respectively, at 400 kN of axle load. A 1.6- and a 2.8-mm-thick CSP were also subjected to axle loading. No yielding or limit states occurred in the 1.6-mm-thick CSP when buried 0.9-m-deep. However, at 0.6 m of cover a 300 kN axle load caused local yielding at the pipe crown. Increasing soil cover from 0.6 to 0.9 m decreased the vertical diameter change from -3.0 to -1.2 mm and the crown bending moment from 0.7 to 0.2 kNm/m (75% and 20% of the yield moment), respectively, at a 250 kN axle load. Deflections of the thicker CSP were less than the thinner pipe below the CL-625 single-axle load, however further increases in applied load produced a greater response in the thicker pipe, likely due to a haunch support issue. Shallow axle loading produced a greater 3-dimensional response and a larger bending effect in both CSPs.

  8. On the roles of solid wall in the thermal analysis of micro heat pipes

    NASA Astrophysics Data System (ADS)

    Hung, Yew Mun

    Micro heat pipe is a small-scale passive heat transfer device of very high thermal conductance that uses phase change and circulation of its working fluid to transfer thermal energy. Different from conventional heat pipe, a micro heat pipe does not contain any wick structure. In this thesis, a one-dimensional, steady-state mathematical model of a single triangular micro heat pipe is developed, with the main purpose of establishing a series of analytical studies on the roles of the solid wall of micro heat pipes in conjunction with the characterization of the thermal performance under the effects of various design and operational parameters. The energy equation of the solid wall is solved analytically to obtain the temperature distribution. The liquid phase is coupled with the solid wall through the continuity of heat flux at their interface, and the continuity, momentum and energy equations of the liquid and vapour phases, together with the Young-Laplace equation for capillary pressure, are solve numerically to yield the heat and fluid flow characteristics of the micro heat pipe. By coupling this mathematical model with the phase-change interfacial resistance model, the relationships for the axial temperature distributions of the liquid and vapour phases throughout the longitudinal direction of a micro heat pipe are also formulated. Four major aspects associated with the operational performance of micro heat pipes are discussed. Firstly, the investigation of the effects of axial conduction in the solid wall reveals that the presence of the solid wall induces change in the phase-change heat transport of the working fluid besides facilitating axial heat conduction in the solid wall. The analysis also highlights the effects of the thickness and thermal conductivity of the solid wall on the axial temperature distribution of solid wall, in the wake of the effects of the axial heat conduction induced on the phase-change heat transport of the working fluid. Secondly, analysis on thermal performance and physical phenomena of an overloaded micro heat pipes incorporating the effects of axial conduction in the solid wall is carried out. The thermal effects of the solid material are investigated and it is observed that the behaviour of the solid wall temperature distribution varies drastically as the applied heat load exceeds the heat transport capacity. The abrupt change in the temperature profile of an overloaded micro heat pipe is of considerable practical significance in which the occurrence of dryout can be identified by physically measuring the solid wall temperatures along the axial direction. Thirdly, by taking into account the axial conduction in the solid wall, the effect of gravity on the thermal performance of an inclined micro heat pipe is explored. Attributed to the occurrence of dryout, an abrupt temperature rise is observed at the evaporator end when the micro heat pipe is negatively inclined. Therefore, the orientation of a micro heat pipe can be determined by physically measuring the solid wall temperature. Lastly, by coupling the heat transfer model of phase-change phenomena at the liquid-vapour interface, the model with axial conduction in the solid wall of the micro heat pipe is extended to predict the axial liquid and vapour temperature distributions of the working fluid, which is useful for the verification of certain assumptions made in the derivation of the mathematical model besides for analyzing the heat transfer characteristics of the evaporation process.

  9. Erosion of water-based fracturing fluid containing particles in a sudden contraction of horizontal pipe

    NASA Astrophysics Data System (ADS)

    Cheng, Jiarui; Cao, Yinping; Dou, Yihua; Li, Zhen

    2017-10-01

    A lab experiment was carried out to study the effects of pipe flow rate, particle concentration and pipe inner diameter ratio on proppant erosion of the reducing wall in hydraulic fracturing. The results show that the erosion rate and erosion distribution are different not only in radial direction but also in circumferential direction of the sample. The upper part of sample always has a minimum erosion rate and erosion area. Besides, the erosion rate of reducing wall is most affected by fluid flow velocity, and the erosion area is most sensitive to the change in the diameter ratio. Meanwhile, the erosion rate of reducing wall in crosslinked fracturing fluid is mainly determined by the fluid flowing state due to the high viscosity of the liquid. In general, the increase in flow velocity and diameter ratio not only cause the expansion of erosion-affected flow region in sudden contraction section, but also lead to more particles impact the wall.

  10. ADVANCED INTEGRATION OF MULTI-SCALE MECHANICS AND WELDING PROCESS SIMULATION IN WELD INTEGRITY ASSESSMENT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilkowski, Gery M.; Rudland, David L.; Shim, Do-Jun

    2008-06-30

    The potential to save trillions of BTU’s in energy usage and billions of dollars in cost on an annual basis based on use of higher strength steel in major oil and gas transmission pipeline construction is a compelling opportunity recognized by both the US Department of Energy (DOE). The use of high-strength steels (X100) is expected to result in energy savings across the spectrum, from manufacturing the pipe to transportation and fabrication, including welding of line pipe. Elementary examples of energy savings include more the 25 trillion BTUs saved annually based on lower energy costs to produce the thinner-walled high-strengthmore » steel pipe, with the potential for the US part of the Alaskan pipeline alone saving more than 7 trillion BTU in production and much more in transportation and assembling. Annual production, maintenance and installation of just US domestic transmission pipeline is likely to save 5 to 10 times this amount based on current planned and anticipated expansions of oil and gas lines in North America. Among the most important conclusions from these studies were: • While computational weld models to predict residual stress and distortions are well-established and accurate, related microstructure models need improvement. • Fracture Initiation Transition Temperature (FITT) Master Curve properly predicts surface-cracked pipe brittle-to-ductile initiation temperature. It has value in developing Codes and Standards to better correlate full-scale behavior from either CTOD or Charpy test results with the proper temperature shifts from the FITT master curve method. • For stress-based flaw evaluation criteria, the new circumferentially cracked pipe limit-load solution in the 2007 API 1104 Appendix A approach is overly conservative by a factor of 4/π, which has additional implications. . • For strain-based design of girth weld defects, the hoop stress effect is the most significant parameter impacting CTOD-driving force and can increase the crack-driving force by a factor of 2 depending on strain-hardening, pressure level as a % of SMYS, and flaw size. • From years of experience in circumferential fracture analyses and experimentation, there has not been sufficient integration of work performed for other industries into analogous problems facing the oil and gas pipeline markets. Some very basic concepts and problems solved previously in these fields could have circumvented inconsistencies seen in the stress-based and strain-based analysis efforts. For example, in nuclear utility piping work, more detailed elastic-plastic fracture analyses were always validated in their ability to predict loads and displacements (stresses and strains). The eventual implementation of these methodologies will result in acceleration of the industry adoption of higher-strength line-pipe steels.« less

  11. 39. Photocopy of scale drawing (from Station 'L' office files, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. Photocopy of scale drawing (from Station 'L' office files, Portland, Oregon) Portland General Electric in house drawing, 5/12/1927 SECTION (TOP) AND ELEVATION (BOTTOM) OF BOILER #9 WHICH IS LOCATED IN THE H.P. BOILER ROOM BUILDING L4, DIAGRAM OF THE GENERAL LAYOUT AND STEAM PIPING OF THE BOILER - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  12. Scaling analysis of gas-liquid two-phase flow pattern in microgravity

    NASA Technical Reports Server (NTRS)

    Lee, Jinho

    1993-01-01

    A scaling analysis of gas-liquid two-phase flow pattern in microgravity, based on the dominant physical mechanism, was carried out with the goal of predicting the gas-liquid two-phase flow regime in a pipe under conditions of microgravity. The results demonstrated the effect of inlet geometry on the flow regime transition. A comparison of the predictions with existing experimental data showed good agreement.

  13. A test of the Feynman scaling in the fragmentation region

    NASA Technical Reports Server (NTRS)

    Doke, T.; Innocente, V.; Kasahara, K.; Kikuchi, J.; Kashiwagi, T.; Lanzano, S.; Masuda, K.; Murakami, H.; Muraki, Y.; Nakada, T.

    1985-01-01

    The result of the direct measurement of the fragmentation region will be presented. The result will be obtained at the CERN proton-antiproton collider, being exposured the Silicon calorimeters inside beam pipe. This experiment clarifies a long riddle of cosmic ray physics, whether the Feynman scaling does villate at the fragmentation region or the Iron component is increasing at 10 to the 15th power eV.

  14. ASSESSING ECOLOGICAL RISKS AT LARGE SPATIAL SCALES

    EPA Science Inventory

    The history of environmental management and regulation in the United States has been one of initial focus on localized, end-of-the-pipe problems to increasing attention to multi-scalar, multi-stressor, and multi- resource issues. Concomitant with this reorientation is the need fo...

  15. Preferential Concentration Of Solid Particles In Turbulent Horizontal Circular Pipe Flow

    NASA Astrophysics Data System (ADS)

    Kim, Jaehee; Yang, Kyung-Soo

    2017-11-01

    In particle-laden turbulent pipe flow, turbophoresis can lead to a preferential concentration of particles near the wall. To investigate this phenomenon, one-way coupled Direct Numerical Simulation (DNS) has been performed. Fully-developed turbulent pipe flow of the carrier fluid (air) is at Reτ = 200 based on the pipe radius and the mean friction velocity, whereas the Stokes numbers of the particles (solid) are St+ = 0.1 , 1 , 10 based on the mean friction velocity and the kinematic viscosity of the fluid. The computational domain for particle simulation is extended along the axial direction by duplicating the domain of the fluid simulation. By doing so, particle statistics in the spatially developing region as well as in the fully-developed region can be obtained. Accumulation of particles has been noticed at St+ = 1 and 10 mostly in the viscous sublayer, more intensive in the latter case. Compared with other authors' previous results, our results suggest that drag force on the particles should be computed by using an empirical correlation and a higher-order interpolation scheme even in a low-Re regime in order to improve the accuracy of particle simulation. This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIP) (No. 2015R1A2A2A01002981).

  16. Monitoring of hot pipes at the power plant Neurath using guided waves

    NASA Astrophysics Data System (ADS)

    Weihnacht, Bianca; Klesse, Thomas; Neubeck, Robert; Schubert, Lars

    2013-04-01

    In order to reduce the CO2-emissions and to increase the energy efficiency, the operating temperatures of power plants will be increased up to 720°C. This demands for novel high-performance steels in the piping systems. Higher temperatures lead to a higher risk of damage and have a direct impact on the structure stability and the deposition structure. Adequately trusted results for the prediction of the residual service life of those high strength steels are not available so far. To overcome these problems the implementation of an online monitoring system in addition to periodic testing is needed. RWE operates the lignite power plant Neurath. All test and research activities have to be checked regarding their safety and have to be coordinated with the business operation of the plant. An extra bypass was established for this research and made the investigations independent from the power plant operating. In order to protect the actuators and sensors from the heat radiated from the pipe, waveguides were welded to the bypass. The data was evaluated regarding their dependencies on the environmental influences like temperature and correction algorithms were developed. Furthermore, damages were introduced into the pipe with diameters of 8 mm to 10 mm and successfully detected by the acoustic method.

  17. Potential impacts of changing supply-water quality on drinking water distribution: A review.

    PubMed

    Liu, Gang; Zhang, Ya; Knibbe, Willem-Jan; Feng, Cuijie; Liu, Wentso; Medema, Gertjan; van der Meer, Walter

    2017-06-01

    Driven by the development of water purification technologies and water quality regulations, the use of better source water and/or upgraded water treatment processes to improve drinking water quality have become common practices worldwide. However, even though these elements lead to improved water quality, the water quality may be impacted during its distribution through piped networks due to the processes such as pipe material release, biofilm formation and detachment, accumulation and resuspension of loose deposits. Irregular changes in supply-water quality may cause physiochemical and microbiological de-stabilization of pipe material, biofilms and loose deposits in the distribution system that have been established over decades and may harbor components that cause health or esthetical issues (brown water). Even though it is clearly relevant to customers' health (e.g., recent Flint water crisis), until now, switching of supply-water quality is done without any systematic evaluation. This article reviews the contaminants that develop in the water distribution system and their characteristics, as well as the possible transition effects during the switching of treated water quality by destabilization and the release of pipe material and contaminants into the water and the subsequent risks. At the end of this article, a framework is proposed for the evaluation of potential transition effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Quality assurance in the production of pipe fittings by automatic laser-based material identification

    NASA Astrophysics Data System (ADS)

    Moench, Ingo; Peter, Laszlo; Priem, Roland; Sturm, Volker; Noll, Reinhard

    1999-09-01

    In plants of the chemical, nuclear and off-shore industry, application specific high-alloyed steels are used for pipe fittings. Mixing of different steel grades can lead to corrosion with severe consequential damages. Growing quality requirements and environmental responsibilities demand a 100% material control in the production of the pipe fittings. Therefore, LIFT, an automatic inspection machine, was developed to insure against any mix of material grades. LIFT is able to identify more than 30 different steel grades. The inspection method is based on Laser-Induced Breakdown Spectrometry (LIBS). An expert system, which can be easily trained and recalibrated, was developed for the data evaluation. The result of the material inspection is transferred to an external handling system via a PLC interface. The duration of the inspection process is 2 seconds. The graphical user interface was developed with respect to the requirements of an unskilled operator. The software is based on a realtime operating system and provides a safe and reliable operation. An interface for the remote maintenance by modem enables a fast operational support. Logged data are retrieved and evaluated. This is the basis for an adaptive improvement of the configuration of LIFT with respect to changing requirements in the production line. Within the first six months of routine operation, about 50000 pipe fittings were inspected.

  19. Acoustic measurements of soil-pipeflow and internal erosion

    USDA-ARS?s Scientific Manuscript database

    Internal erosion of soil pipes can lead to embankment failures, landslides, and gully erosion. Therefore, non-intrusive methods are needed to detect and monitor soil pipeflow and the resulting internal erosion. This paper presents a laboratory study using both active and passive acoustic techniques ...

  20. Acoustic measurements of soil pipeflow and internal erosion

    USDA-ARS?s Scientific Manuscript database

    Internal erosion of soil pipes can lead to embankment failures, landslides, and gully erosion therefore non-intrusive methods are needed to detect and monitor soil pipeflow and the resulting internal erosion. This paper presents a laboratory study using both active and passive acoustic techniques to...

  1. COPPER PITTING CORROSION: A CASE STUDY

    EPA Science Inventory

    Localized or pitting corrosion of copper pipes used in household drinking-water plumbing is a problem for many water utilities and their customers. Extreme attack can lead to pinhole water leaks that may result in water damage, mold growth, and costly repairs. Water quality has b...

  2. Condensation on Highly Superheated Surfaces: Unstable Thin Films in a Wickless Heat Pipe

    NASA Astrophysics Data System (ADS)

    Kundan, Akshay; Nguyen, Thao T. T.; Plawsky, Joel L.; Wayner, Peter C.; Chao, David F.; Sicker, Ronald J.

    2017-03-01

    A wickless heat pipe was operated on the International Space Station to provide a better understanding of how the microgravity environment might alter the physical and interfacial forces driving evaporation and condensation. Traditional heat pipes are divided into three zones: evaporation at the heated end, condensation at the cooled end, and intermediate or adiabatic in between. The microgravity experiments reported herein show that the situation may be dramatically more complicated. Beyond a threshold heat input, there was a transition from evaporation at the heated end to large-scale condensation, even as surface temperatures exceeded the boiling point by 160 K. The hotter the surface, the more vapor was condensed onto it. The condensation process at the heated end is initiated by thickness and temperature disturbances in the thin liquid film that wet the solid surface. Those disturbances effectively leave the vapor "superheated" in that region. Condensation is amplified and sustained by the high Marangoni stresses that exist near the heater and that drive liquid to cooler regions of the device.

  3. Miniature Loop Heat Pipe with Multiple Evaporators for Thermal Control of Small Spacecraft

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Ottenstein, Laura; Douglas, Denya; Pauken, Michael; Birur, Gajanana

    2005-01-01

    This paper presents an advanced miniature heat transport system for thermal control of small spacecraft. The thermal system consists of a loop heat pipe (LHP) with multiple evaporators and multiple deployable radiators for heat transfer, and variable emittance coatings on the radiators for performance enhancement. Thermoelectric coolers are used to control the loop operating temperature. The thermal system combines the functions of variable conductance heat pipes, thermal switches, thermal diodes, and the state-of-the-art LHPs into a single integrated thermal system. It retains all the performance characteristics of state-of-the-art LHPs and offers additional advantages to enhance the functionality, performance, versatility, and reliability of the system. Steady state and transient analytical models have been developed, and scaling criteria have also been established. A breadboard unit has been built for functional testing in laboratory and thermal vacuum environments. Experimental results show excellent performance of the thermal system and correlate very well with theoretical predictions.

  4. Iron and copper release in drinking-water distribution systems.

    PubMed

    Shi, Baoyou; Taylor, James S

    2007-09-01

    A large-scale pilot study was carried out to evaluate the impacts of changes in water source and treatment process on iron and copper release in water distribution systems. Finished surface waters, groundwaters, and desalinated waters were produced with seven different treatment systems and supplied to 18 pipe distribution systems (PDSs). The major water treatment processes included lime softening, ferric sulfate coagulation, reverse osmosis, nanofiltration, and integrated membrane systems. PDSs were constructed from PVC, lined cast iron, unlined cast iron, and galvanized pipes. Copper pipe loops were set up for corrosion monitoring. Results showed that surface water after ferric sulfate coagulation had low alkalinity and high sulfates, and consequently caused the highest iron release. Finished groundwater treated by conventional method produced the lowest iron release but the highest copper release. The iron release of desalinated water was relatively high because of the water's high chloride level and low alkalinity. Both iron and copper release behaviors were influenced by temperature.

  5. Social and Built Environmental Correlates of Predicted Blood Lead Levels in the Flint Water Crisis.

    PubMed

    Sadler, Richard Casey; LaChance, Jenny; Hanna-Attisha, Mona

    2017-05-01

    To highlight contextual factors tied to increased blood lead level (BLL) risk following the lead-in-water contamination in Flint, Michigan. Using geocoded BLL data collected in 2013 and 2015 and areal interpolation, we predicted BLLs at every residential parcel in the city. We then spatially joined social and built environmental variables to link the parcels with neighborhood-level factors that may influence BLLs. When we compared levels before and during the water crisis, we saw the highest estimates of predicted BLLs during the water crisis and the greatest changes in BLLs in neighborhoods with the longest water residence time in pipes (μ = 2.30 µg/dL; Δ = 0.45 µg/dL), oldest house age (μ = 2.22 µg/dL; Δ = 0.37 µg/dL), and poorest average neighborhood housing condition (μ = 2.18 µg/dL; Δ = 0.44 µg/dL). Key social and built environmental variables correlate with BLL; such information can continue to guide response by prioritizing older, deteriorating neighborhoods with the longest water residence time in pipes.

  6. Effects of Ni(2+) on aluminum hydroxide scale formation and transformation on a simulated drinking water distribution system.

    PubMed

    Wang, Wendong; Song, Shan; Zhang, Xiaoni; Mitchell Spear, J; Wang, Xiaochang; Wang, Wen; Ding, Zhenzhen; Qiao, Zixia

    2014-07-01

    Observations of aluminum containing sediments/scales formed within the distribution pipes have been reported for several decades. In this study, the effect of Ni(2+) on the formation and transformation processes of aluminum hydroxide sediment in a simulated drinking water distribution system were investigated using X-ray diffraction spectrum (XRD), Fourier transform infrared spectrum (FT-IR), scanning electron microscope (SEM), and thermodynamic calculation methods. It was determined that the existence of Ni(2+) had notable effects on the formation of bayerite. In the system without Ni(2+) addition, there was no X-ray diffraction signal observed after 400 d of aging. The presence of Ni(2+), however, even when present in small amounts (Ni/Al=1:100) the formation of bayerite would occur in as little as 3d at pH 8.5. As the molar ratio of Ni/Al increase from 1:100 to 1:10, the amount of bayerite formed on the pipeline increased further; meanwhile, the specific area of the pipe scale decreased from 160 to 122 m(2)g(-1). In the system with Ni/Al molar ratio at 1:3, the diffraction spectrum strength of bayerite became weaker, and disappeared when Ni/Al molar ratios increased above 1:1. At these highs Ni/Al molar ratios, Ni5Al4O11⋅18H2O was determined to be the major component of the pipe scale. Further study indicated that the presence of Ni(2+) promoted the formation of bayerite and Ni5Al4O11⋅18H2O under basic conditions. At lower pH (6.5) however, the existence of Ni(2+) had little effect on the formation of bayerite and Ni5Al4O11⋅18H2O, rather the adsorption of amorphous Al(OH)3 for Ni(2+) promoted the formation of crystal Ni(OH)2. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Hydraulic Roughness and Flow Resistance in a Subglacial Conduit

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Liu, X.; Mankoff, K. D.

    2017-12-01

    The hydraulic roughness significantly affects the flow resistance in real subglacial conduits, but has been poorly understood. To address this knowledge gap, this paper first proposes a procedure to define and quantify the geometry roughness, and then relates such a geometry roughness to the hydraulic roughness based on a series of computational fluid dynamics (CFD) simulations. The results indicate that by using the 2nd order structure function, the roughness field can be well quantified by the powers of the scaling-law, the vertical and horizontal length scales of the structure functions. The vertical length scale can be further chosen as the standard deviation of the roughness field σr. The friction factors calculated from either total drag force or the linear decreasing pressure agree very well with those calculated from traditional rough pipe theories when the equivalent hydraulic roughness height is corrected as ks = (1.1 ˜ 1.5)σr. This result means that the fully rough pipe resistance formula λ = [2 log(D0/2ks) + 1.74]-2, and the Moody diagram are still valid for the friction factor estimation in subglacial conduits when σr /D0<18% and ks/D0<22%. The results further show that when a proper hydraulic roughness is determined, the total flow resistance corresponding to the given hydraulic roughness height can be accurately modelled by using a rough wall function. This suggests that the flow resistance for the longer realistic subglacial conduits with large sinuosity and cross-sectional variations may be correctly predicted by CFD simulations. The results also show that the friction factors from CFD modeling are much larger than those determined from traditional rough pipe theories when σr /D0>20%.

  8. Habitat selection and movements of Piping Plover broods suggest a tradeoff between breeding stages

    USGS Publications Warehouse

    Wiltermuth, Mark T.; Anteau, Michael J.; Sherfy, Mark H.; Pearse, Aaron T.

    2015-01-01

    In precocial birds, adults select breeding areas using cues associated with habitat characteristics that are favorable for nesting success and chick survival, but there may be tradeoffs in habitat selection between these breeding stages. Here we describe habitat selection and intra-territory movements of 53 Piping Plover (Charadrius melodus) broods (320 observations) during the 2007–2008 breeding seasons on mainland- and island-shoreline habitats at Lake Sakakawea, North Dakota, USA. We used remotely sensed habitat characteristics to separately examine habitat selection and movements at two spatiotemporal scales to account for potential confounding effects of nest-site selection on brood-rearing habitat used. The scales used were (1) the entire brood-rearing period within available brood-rearing areas and (2) 2-day observation intervals within age-specific discrete habitat selection choice sets. Analyses at both scales indicated that broods selected areas which were non-vegetated, moderately level, and nearer to the shoreline. Rate of brood movement increased with age up to 5 days, then stabilized; broods that hatched >50 m away from the shoreline moved toward the shoreline. Brood movements were greater when they were in vegetated areas, when the brood-rearing area was of greater topographic complexity, and when broods aged 6–25 days were further away from the shoreline. Using inferences from our results and those of previously published work, we postulate how a potential tradeoff in habitat selection between nesting and brood-rearing can contribute to an ecological trap in a novel habitat. This work, in the context of published works, suggests that plover breeding habitat is a complex of both nesting and brood-rearing habitats and provides a basis for making remotely sensed abundance estimates of suitable breeding habitat for Piping Plovers.

  9. Optimal Design and Operation of Permanent Irrigation Systems

    NASA Astrophysics Data System (ADS)

    Oron, Gideon; Walker, Wynn R.

    1981-01-01

    Solid-set pressurized irrigation system design and operation are studied with optimization techniques to determine the minimum cost distribution system. The principle of the analysis is to divide the irrigation system into subunits in such a manner that the trade-offs among energy, piping, and equipment costs are selected at the minimum cost point. The optimization procedure involves a nonlinear, mixed integer approach capable of achieving a variety of optimal solutions leading to significant conclusions with regard to the design and operation of the system. Factors investigated include field geometry, the effect of the pressure head, consumptive use rates, a smaller flow rate in the pipe system, and outlet (sprinkler or emitter) discharge.

  10. Rapid 3D Printing of Multifunctional Calcium Alginate Gel Pipes using Coaxial Jet Extruder

    NASA Astrophysics Data System (ADS)

    Rykaczewski, Konrad; Damle, Viraj

    2014-11-01

    Calcium alginate (CA) forms when solution containing sodium alginate (SA) comes in contact with a CaCl2 solution. The resulting gel is biocompatible as well as edible and is used in production of bio-scaffolds, artificial plant seeds, and edible substances. In the latter application, referred to in the culinary world as ``spherification,'' flavored liquids are mixed with the SA and dripped into CaCl2 solution to form gel encapsulated flavored ``marbles.'' Previously, crude 3D printing of CA structures has been achieved by stacking of such flavored liquid filled marbles. In turn, solid CA rods have been fabricated by properly mixing flow of the two solutions using a microfluidic device. Here we show that by using two circular cross-section coaxial nozzles to produce coaxial jets of the SA and CaCl2 solutions, liquid filled CA micro-to-mili scale gel pipes can be produced at speeds around ~ 150 mm/s. Such extrusion rate is compatible with most commercially available 3D printers, facilitating adoption of the CA pipe coaxial jet extruder. Here, the impact of inner and outer liquid properties and flow speeds on the gel pipe extrusion process is discussed. KR acknowledges startup funding from ASU.

  11. Turbulent pipe flow at extreme Reynolds numbers.

    PubMed

    Hultmark, M; Vallikivi, M; Bailey, S C C; Smits, A J

    2012-03-02

    Both the inherent intractability and complex beauty of turbulence reside in its large range of physical and temporal scales. This range of scales is captured by the Reynolds number, which in nature and in many engineering applications can be as large as 10(5)-10(6). Here, we report turbulence measurements over an unprecedented range of Reynolds numbers using a unique combination of a high-pressure air facility and a new nanoscale anemometry probe. The results reveal previously unknown universal scaling behavior for the turbulent velocity fluctuations, which is remarkably similar to the well-known scaling behavior of the mean velocity distribution.

  12. Disinfection Addition and Disinfection Changes: What It Means to the LCR

    EPA Science Inventory

    This slide presentation’s general points are: Many protective pipe scales are vey dependent on ORP, and hence, state of disinfection. Adding disinfection to anoxic systems will likely cause big chemistry changes in DS and corrosion. Changing disinfectants could cause major l...

  13. Method to measure efficiently rare fluctuations of turbulence intensity for turbulent-laminar transitions in pipe flows

    NASA Astrophysics Data System (ADS)

    Nemoto, Takahiro; Alexakis, Alexandros

    2018-02-01

    The fluctuations of turbulence intensity in a pipe flow around the critical Reynolds number is difficult to study but important because they are related to turbulent-laminar transitions. We here propose a rare-event sampling method to study such fluctuations in order to measure the time scale of the transition efficiently. The method is composed of two parts: (i) the measurement of typical fluctuations (the bulk part of an accumulative probability function) and (ii) the measurement of rare fluctuations (the tail part of the probability function) by employing dynamics where a feedback control of the Reynolds number is implemented. We apply this method to a chaotic model of turbulent puffs proposed by Barkley and confirm that the time scale of turbulence decay increases super exponentially even for high Reynolds numbers up to Re =2500 , where getting enough statistics by brute-force calculations is difficult. The method uses a simple procedure of changing Reynolds number that can be applied even to experiments.

  14. Characterization of elemental and structural composition of corrosion scales and deposits formed in drinking water distribution systems.

    PubMed

    Peng, Ching-Yu; Korshin, Gregory V; Valentine, Richard L; Hill, Andrew S; Friedman, Melinda J; Reiber, Steve H

    2010-08-01

    Corrosion scales and deposits formed within drinking water distribution systems (DWDSs) have the potential to retain inorganic contaminants. The objective of this study was to characterize the elemental and structural composition of extracted pipe solids and hydraulically-mobile deposits originating from representative DWDSs. Goethite (alpha-FeOOH), magnetite (Fe(3)O(4)) and siderite (FeCO(3)) were the primary crystalline phases identified in most of the selected samples. Among the major constituent elements of the deposits, iron was most prevalent followed, in the order of decreasing prevalence, by sulfur, organic carbon, calcium, inorganic carbon, phosphorus, manganese, magnesium, aluminum and zinc. The cumulative occurrence profiles of iron, sulfur, calcium and phosphorus for pipe specimens and flushed solids were similar. Comparison of relative occurrences of these elements indicates that hydraulic disturbances may have relatively less impact on the release of manganese, aluminum and zinc, but more impact on the release of organic carbon, inorganic carbon, and magnesium. (c) 2010 Elsevier Ltd. All rights reserved.

  15. Effectiveness of Devices to Monitor Biofouling and Metals Deposition on Plumbing Materials Exposed to a Full-Scale Drinking Water Distribution System

    PubMed Central

    Garbin, Scott; Wylie, Jason; Krishna, K. C. Bal

    2017-01-01

    A Modified Robbins Device (MRD) was installed in a full-scale water distribution system to investigate biofouling and metal depositions on concrete, high-density polyethylene (HDPE) and stainless steel surfaces. Bulk water monitoring and a KIWA monitor (with glass media) were used to offline monitor biofilm development on pipe wall surfaces. Results indicated that adenosine triphosphate (ATP) and metal concentrations on coupons increased with time. However, bacterial diversities decreased. There was a positive correlation between increase of ATP and metal deposition on pipe surfaces of stainless steel and HDPE and no correlation was observed on concrete and glass surfaces. The shared bacterial diversity between bulk water and MRD was less than 20% and the diversity shared between the MRD and KIWA monitor was only 10%. The bacterial diversity on biofilm of plumbing material of MRD however, did not show a significant difference suggesting a lack of influence from plumbing material during early stage of biofilm development. PMID:28060947

  16. IMPACT OF WATER CHEMISTRY ON LOCALIZED CORROSION OF COPPER PITTING

    EPA Science Inventory

    This project will help identify what waters are problematic in causing the corrosion of copper pipes and improve understanding of how water distribution leads to corrosion. This project will also focus on the prevention of pinhole leaks and how to reverse them once they occur. ...

  17. CHARACTERIZATION OF LOCALIZED CORROSION OF COPPER PIPES USED IN DRINKING WATER

    EPA Science Inventory

    Localized corrosion of copper, or "copper pitting" in water distribution tubing is a large problem at many utilities. Pitting can lead to pinhole leaks less than a year. Tubing affected by copper pitting will often fail in ultiple locations, resulting in a frustrating situation ...

  18. Problems with the random number generator RANF implemented on the CDC cyber 205

    NASA Astrophysics Data System (ADS)

    Kalle, Claus; Wansleben, Stephan

    1984-10-01

    We show that using RANF may lead to wrong results when lattice models are simulated by Monte Carlo methods. We present a shift-register sequence random number generator which generates two random numbers per cycle on a two pipe CDC Cyber 205.

  19. Otrag rocket experiments in Africa

    NASA Technical Reports Server (NTRS)

    1978-01-01

    West German rocket manufacturers are testing their products in Zaire. Hundreds of pipes (12 m x 80 cm) are bundled together inside the test missiles, which are fired into Zaire's prairie. The reactions of neighboring nations, as well as leading countries of the world, are presented concerning the rocket tests.

  20. Effect of disinfectant, water age, and pipe materials on bacterial and eukaryotic community structure in drinking water biofilm.

    PubMed

    Wang, Hong; Masters, Sheldon; Edwards, Marc A; Falkinham, Joseph O; Pruden, Amy

    2014-01-01

    Availability of safe, pathogen-free drinking water is vital to public health; however, it is impossible to deliver sterile drinking water to consumers. Recent microbiome research is bringing new understanding to the true extent and diversity of microbes that inhabit water distribution systems. The purpose of this study was to determine how water chemistry in main distribution lines shape the microbiome in drinking water biofilms and to explore potential associations between opportunistic pathogens and indigenous drinking water microbes. Effects of disinfectant (chloramines, chlorine), water age (2.3 days, 5.7 days), and pipe material (cement, iron, PVC) were compared in parallel triplicate simulated water distribution systems. Pyrosequencing was employed to characterize bacteria and terminal restriction fragment polymorphism was used to profile both bacteria and eukaryotes inhabiting pipe biofilms. Disinfectant and water age were both observed to be strong factors in shaping bacterial and eukaryotic community structures. Pipe material only influenced the bacterial community structure (ANOSIM test, P < 0.05). Interactive effects of disinfectant, pipe material, and water age on both bacteria and eukaryotes were noted. Disinfectant concentration had the strongest effect on bacteria, while dissolved oxygen appeared to be a major driver for eukaryotes (BEST test). Several correlations of similarity metrics among populations of bacteria, eukaryotes, and opportunistic pathogens, as well as one significant association between mycobacterial and proteobacterial operational taxonomic units, provides insight into means by which manipulating the microbiome may lead to new avenues for limiting the growth of opportunistic pathogens (e.g., Legionella) or other nuisance organisms (e.g., nitrifiers).

  1. Beam loss reduction by magnetic shielding using beam pipes and bellows of soft magnetic materials

    NASA Astrophysics Data System (ADS)

    Kamiya, J.; Ogiwara, N.; Hotchi, H.; Hayashi, N.; Kinsho, M.

    2014-11-01

    One of the main sources of beam loss in high power accelerators is unwanted stray magnetic fields from magnets near the beam line, which can distort the beam orbit. The most effective way to shield such magnetic fields is to perfectly surround the beam region without any gaps with a soft magnetic high permeability material. This leads to the manufacture of vacuum chambers (beam pipes and bellows) with soft magnetic materials. A Ni-Fe alloy (permalloy) was selected for the material of the pipe parts and outer bellows parts, while a ferritic stainless steel was selected for the flanges. An austenitic stainless steel, which is non-magnetic material, was used for the inner bellows for vacuum tightness. To achieve good magnetic shielding and vacuum performances, a heat treatment under high vacuum was applied during the manufacturing process of the vacuum chambers. Using this heat treatment, the ratio of the integrated magnetic flux density along the beam orbit between the inside and outside of the beam pipe and bellows became small enough to suppress beam orbit distortion. The outgassing rate of the materials with this heat treatment was reduced by one order magnitude compared to that without heat treatment. By installing the beam pipes and bellows of soft magnetic materials as part of the Japan Proton Accelerator Research Complex 3 GeV rapid cycling synchrotron beam line, the closed orbit distortion (COD) was reduced by more than 80%. In addition, a 95.5% beam survival ratio was achieved by this COD improvement.

  2. Low-frequency fluid waves in fractures and pipes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Korneev, Valeri

    2010-09-01

    Low-frequency analytical solutions have been obtained for phase velocities of symmetrical fluid waves within both an infinite fracture and a pipe filled with a viscous fluid. Three different fluid wave regimes can exist in such objects, depending on the various combinations of parameters, such as fluid density, fluid viscosity, walls shear modulus, channel thickness, and frequency. Equations for velocities of all these regimes have explicit forms and are verified by comparisons with the exact solutions. The dominant role of fractures in rock permeability at field scales and the strong amplitude and frequency effects of Stoneley guided waves suggest the importancemore » of including these wave effects into poroelastic theories.« less

  3. Filamentous hydrous ferric oxide biosignatures in a pipeline carrying acid mine drainage at Iron Mountain Mine, California

    USGS Publications Warehouse

    Williams, Amy J.; Alpers, Charles N.; Sumner, Dawn Y.; Campbell, Kate M.

    2017-01-01

    A pipeline carrying acidic mine effluent at Iron Mountain, CA, developed Fe(III)-rich precipitate caused by oxidation of Fe(II)aq. The native microbial community in the pipe included filamentous microbes. The pipe scale consisted of microbial filaments, and schwertmannite (ferric oxyhydroxysulfate, FOHS) mineral spheres and filaments. FOHS filaments contained central lumina with diameters similar to those of microbial filaments. FOHS filament geometry, the geochemical environment, and the presence of filamentous microbes suggest that FOHS filaments are mineralized microbial filaments. This formation of textural biosignatures provides the basis for a conceptual model for the development and preservation of biosignatures in other environments.

  4. Heat extraction from salinity-gradient solar ponds using heat pipe heat exchangers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tundee, Sura; Terdtoon, Pradit; Sakulchangsatjatai, Phrut

    This paper presents the results of experimental and theoretical analysis on the heat extraction process from solar pond by using the heat pipe heat exchanger. In order to conduct research work, a small scale experimental solar pond with an area of 7.0 m{sup 2} and a depth of 1.5 m was built at Khon Kaen in North-Eastern Thailand (16 27'N102 E). Heat was successfully extracted from the lower convective zone (LCZ) of the solar pond by using a heat pipe heat exchanger made from 60 copper tubes with 21 mm inside diameter and 22 mm outside diameter. The length ofmore » the evaporator and condenser section was 800 mm and 200 mm respectively. R134a was used as the heat transfer fluid in the experiment. The theoretical model was formulated for the solar pond heat extraction on the basis of the energy conservation equations and by using the solar radiation data for the above location. Numerical methods were used to solve the modeling equations. In the analysis, the performance of heat exchanger is investigated by varying the velocity of inlet air used to extract heat from the condenser end of the heat pipe heat exchanger (HPHE). Air velocity was found to have a significant influence on the effectiveness of heat pipe heat exchanger. In the present investigation, there was an increase in effectiveness by 43% as the air velocity was decreased from 5 m/s to 1 m/s. The results obtained from the theoretical model showed good agreement with the experimental data. (author)« less

  5. Convective Mixing in Distal Pipes Exacerbates Legionella pneumophila Growth in Hot Water Plumbing.

    PubMed

    Rhoads, William J; Pruden, Amy; Edwards, Marc A

    2016-03-12

    Legionella pneumophila is known to proliferate in hot water plumbing systems, but little is known about the specific physicochemical factors that contribute to its regrowth. Here, L. pneumophila trends were examined in controlled, replicated pilot-scale hot water systems with continuous recirculation lines subject to two water heater settings (40 °C and 58 °C) and three distal tap water use frequencies (high, medium, and low) with two pipe configurations (oriented upward to promote convective mixing with the recirculating line and downward to prevent it). Water heater temperature setting determined where L. pneumophila regrowth occurred in each system, with an increase of up to 4.4 log gene copies/mL in the 40 °C system tank and recirculating line relative to influent water compared to only 2.5 log gene copies/mL regrowth in the 58 °C system. Distal pipes without convective mixing cooled to room temperature (23-24 °C) during periods of no water use, but pipes with convective mixing equilibrated to 30.5 °C in the 40 °C system and 38.8 °C in the 58 °C system. Corresponding with known temperature effects on L. pneumophila growth and enhanced delivery of nutrients, distal pipes with convective mixing had on average 0.2 log more gene copies/mL in the 40 °C system and 0.8 log more gene copies/mL in the 58 °C system. Importantly, this work demonstrated the potential for thermal control strategies to be undermined by distal taps in general, and convective mixing in particular.

  6. The dependence of chlorine decay and DBP formation kinetics on pipe flow properties in drinking water distribution.

    PubMed

    Zhao, Yingying; Yang, Y Jeffrey; Shao, Yu; Neal, Jill; Zhang, Tuqiao

    2018-04-27

    Simultaneous chlorine decay and disinfection byproduct (DBP) formation have been discussed extensively because of their regulatory and operational significance. This study further examines chemical reaction variability in the water quality changes under various hydrodynamic conditions in drinking water distribution. The variations of kinetic constant for overall chlorine decay (k E ) and trihalomethane (THM) formation were determined under stagnant to turbulent flows using three devices of different wall demand and two types of natural organic matters (NOM) in water. The results from the comparative experiments and modeling analyses show the relative importance of wall demand (k w ), DBP-forming chlorine decay (k D ), and other bulk demand (k b ' ) for pipe flows of Re = 0-52500. It is found that chlorine reactivity of virgin NOM is the overriding factor. Secondly, for tap water NOM of lower reactivity, pipe flow properties (Re or u) can significantly affect k E , the THM yield (T), formation potential (Y), and the time to reach the maximum THM concentration (t max ) through their influence on kinetic ratio k D (k b ' +k w ). These observations, corroborating with turbidity variations during experiments, cannot be explained alone by chlorine dispersion to and from the pipe wall. Mass exchanges through deposition and scale detachment, most likely being flow-dependent, may have contributed to the overall chlorine decay and DBP formation rates. Thus for the simultaneous occurrence of chlorine decay and DBP formation, model considerations of NOM reactivity, pipe types (wall demand), flow hydraulics, and their interactions are essential. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Insoluble coatings for Stirling engine heat pipe condenser surfaces

    NASA Astrophysics Data System (ADS)

    Dussinger, Peter M.

    1993-09-01

    The work done by Thermacore, Inc., Lancaster, Pennsylvania, for the Phase 1, 1992 SBIR National Aeronautics and Space Administration Contract, 'Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces' is described. The work was performed between January 1992 and July 1992. Stirling heat engines are being developed for electrical power generation use on manned and unmanned earth orbital and planetary missions. Dish Stirling solar systems and nuclear reactor Stirling systems are two of the most promising applications of the Stirling engine electrical power generation technology. The sources of thermal energy used to drive the Stirling engine typically are non-uniform in temperature and heat flux. Liquid metal heat pipe receivers are used as thermal transformers and isothermalizers to deliver the thermal energy at a uniform high temperature to the heat input section of the Stirling engine. The use of a heat pipe receiver greatly enhances system efficiency and potential life span. One issue that is raised during the design phase of heat pipe receivers is the potential solubility corrosion of the Stirling engine heat input section by the liquid metal working fluid. This Phase 1 effort initiated a program to evaluate and demonstrate coatings, applied to nickel based Stirling engine heater head materials, that are practically 'insoluble' in sodium, potassium, and NaK. This program initiated a study of nickel aluminide as a coating and developed and demonstrated a heat pipe test vehicle that can be used to test candidate materials and coatings. Nickel 200 and nickel aluminide coated Nickel 200 were tested for 1000 hours at 800 C at a condensation heat flux of 25 W/sq cm. Subsequent analyses of the samples showed no visible sign of solubility corrosion of either coated or uncoated samples. The analysis technique, photomicrographs at 200X, has a resolution of better than 2.5 microns (.0001 in). The results indicate that the heat pipe environment is not directly comparable to liquid metal pumped loop data, that nickel aluminide is still a leading candidate for solubility corrosion protection, and that longer duration tests are required to reach a definitive conclusion whether coatings are required at all. Should further testing be required, the test vehicle and analytical tools were developed.

  8. Insoluble coatings for Stirling engine heat pipe condenser surfaces

    NASA Technical Reports Server (NTRS)

    Dussinger, Peter M.

    1993-01-01

    The work done by Thermacore, Inc., Lancaster, Pennsylvania, for the Phase 1, 1992 SBIR National Aeronautics and Space Administration Contract, 'Insoluble Coatings for Stirling Engine Heat Pipe Condenser Surfaces' is described. The work was performed between January 1992 and July 1992. Stirling heat engines are being developed for electrical power generation use on manned and unmanned earth orbital and planetary missions. Dish Stirling solar systems and nuclear reactor Stirling systems are two of the most promising applications of the Stirling engine electrical power generation technology. The sources of thermal energy used to drive the Stirling engine typically are non-uniform in temperature and heat flux. Liquid metal heat pipe receivers are used as thermal transformers and isothermalizers to deliver the thermal energy at a uniform high temperature to the heat input section of the Stirling engine. The use of a heat pipe receiver greatly enhances system efficiency and potential life span. One issue that is raised during the design phase of heat pipe receivers is the potential solubility corrosion of the Stirling engine heat input section by the liquid metal working fluid. This Phase 1 effort initiated a program to evaluate and demonstrate coatings, applied to nickel based Stirling engine heater head materials, that are practically 'insoluble' in sodium, potassium, and NaK. This program initiated a study of nickel aluminide as a coating and developed and demonstrated a heat pipe test vehicle that can be used to test candidate materials and coatings. Nickel 200 and nickel aluminide coated Nickel 200 were tested for 1000 hours at 800 C at a condensation heat flux of 25 W/sq cm. Subsequent analyses of the samples showed no visible sign of solubility corrosion of either coated or uncoated samples. The analysis technique, photomicrographs at 200X, has a resolution of better than 2.5 microns (.0001 in). The results indicate that the heat pipe environment is not directly comparable to liquid metal pumped loop data, that nickel aluminide is still a leading candidate for solubility corrosion protection, and that longer duration tests are required to reach a definitive conclusion whether coatings are required at all. Should further testing be required, the test vehicle and analytical tools were developed.

  9. The Effect of Water Chemistry on the Release of Iron from Pipe Walls

    EPA Science Inventory

    Colored water problems originating from distribution system materials may be reduced by controlling corrosion, iron released from corrosion scales, and better understanding of the form and properties of the iron particles. The objective of this research was to evaluate the effect...

  10. URBAN STREAM BURIAL INCREASES WATERSHED-SCALE NITRATE EXPORT

    EPA Science Inventory

    Nitrogen (N) uptake in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial reduces the capacity of streams to remove nitrate (NO3-) from the water column by in...

  11. THE RELATIONSHIP BETWEEN THE CORROSION OF DISTRIBUTION SYSTEM MATERIALS, AND OXIDANT AND REDOX POTENTIAL

    EPA Science Inventory

    Scale build-up, corrosion rate, and metal release associated with drinking water distribution system pipes have been suggested to relate to the oxidant type and concentration. Conversely, different distribution system metals may exert different oxidant demands. The impact of ox...

  12. From Strategic to Tactical and Nowhere in Between: The USAF at the Operational Level

    DTIC Science & Technology

    2012-06-01

    stove piped, lacking the balance to operate effectively across the full ROMO. Finally, the lack of balance combined with the dual responsibilities...was able to reorganize and lead effectively . As for 12AF (AFSOUTH), despite a lack of balance on the staff leading to a slow transition to support...development, the teams focused on three central elements: a standardized organizational structure, manned with a cross-functionally balance staff to support

  13. Pitting Corrosion of Copper in Waters with High pH and Low Alkalinity

    EPA Science Inventory

    Localized or pitting corrosion of copper pipes used in household drinking-water plumbing is a problem for many water utilities and their customers. Extreme attack can lead to pinhole water leaks that may result in water damage, mold growth, and costly repairs. Water quality has b...

  14. 25. Detail, roof at junction of main roof and tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. Detail, roof at junction of main roof and tower skirt roof; note condition of slates, subroof, missing gutter, lead pipe gutter outlet; view to northwest from lift-bed truck, 135mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  15. 36. VIEW OF FRAMING BENT BETWEEN SECONDARY THICKENER No. 3 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. VIEW OF FRAMING BENT BETWEEN SECONDARY THICKENER No. 3 AND PRIMARY THICKENER No. 2 FROM WEST. NOTE MECHANISM ON PRIMARY No. 2 ON LEFT, BARREN SOLUTION FEED PIPE AT LOWER RIGHT. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  16. 15. BALD MOUNTAIN MILL, INTERIOR SHOWING PRECIPITATION AREA FROM NORTH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. BALD MOUNTAIN MILL, INTERIOR SHOWING PRECIPITATION AREA FROM NORTH, c. 1934. SHOWS PRECIPITATION TANK No. 1 (NOTE LOCKS), ZINC FEEDER WITH MIXING CONE, VACUUM RECEIVER AND PIPING. CREDIT WR. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  17. Use of Carbon Steel for Construction of Post-combustion CO 2 Capture Facilities: A Pilot-Scale Corrosion Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Wei; Landon, James; Irvin, Bradley

    Corrosion studies were carried out on metal coated and noncoated carbon steel as well as stainless steel in a pilot-scale post-combustion CO 2 capture process. Aqueous 30 wt % monoethanolamine (MEA) solvent was used without any chemical additive for antioxidation to examine a worst-case scenario where corrosion is not mitigated. The corrosion rate of all carbon steels was almost zero in the absorber column and CO 2 lean amine piping except for Ni-coated carbon steel (<1.8 mm/yr). Ni 2Al 3/Al 2O 3 precoated carbon steels showed initial protection but lost their integrity in the stripping column and CO 2 richmore » amine piping, and severe corrosion was eventually observed for all carbon steels at these two locations. Stainless steel was found to be stable and corrosion resistant in all of the sampling locations throughout the experiment. This study provides an initial framework for the use of carbon steel as a potential construction material for process units with relatively mild operating conditions (temperature less than 80 °C), such as the absorber and CO 2 lean amine piping of a post-combustion CO 2 capture process. As a result, it also warrants further investigation of using carbon steel with more effective corrosion mitigation strategies for process units where harsh environments are expected (such as temperatures greater than 100 °C).« less

  18. Use of Carbon Steel for Construction of Post-combustion CO 2 Capture Facilities: A Pilot-Scale Corrosion Study

    DOE PAGES

    Li, Wei; Landon, James; Irvin, Bradley; ...

    2017-04-13

    Corrosion studies were carried out on metal coated and noncoated carbon steel as well as stainless steel in a pilot-scale post-combustion CO 2 capture process. Aqueous 30 wt % monoethanolamine (MEA) solvent was used without any chemical additive for antioxidation to examine a worst-case scenario where corrosion is not mitigated. The corrosion rate of all carbon steels was almost zero in the absorber column and CO 2 lean amine piping except for Ni-coated carbon steel (<1.8 mm/yr). Ni 2Al 3/Al 2O 3 precoated carbon steels showed initial protection but lost their integrity in the stripping column and CO 2 richmore » amine piping, and severe corrosion was eventually observed for all carbon steels at these two locations. Stainless steel was found to be stable and corrosion resistant in all of the sampling locations throughout the experiment. This study provides an initial framework for the use of carbon steel as a potential construction material for process units with relatively mild operating conditions (temperature less than 80 °C), such as the absorber and CO 2 lean amine piping of a post-combustion CO 2 capture process. As a result, it also warrants further investigation of using carbon steel with more effective corrosion mitigation strategies for process units where harsh environments are expected (such as temperatures greater than 100 °C).« less

  19. High-resolution reconstruction of Arctic paleoclimate derived from 53 million year old kimberlite-hosted Metasequoia wood

    NASA Astrophysics Data System (ADS)

    Walker, J. J.; Halfar, J.; Schulze, D.; Gedalof, Z.; Moore, G. W. K.

    2009-04-01

    The recovery of exceptionally well preserved Eocene wood from kimberlite pipes in the Lac de Gras region of the Northwest Territories, Canada, has allowed for the characterization of the local temperature and hydrologic patterns on an annual scale for this arctic ecosystem (present day latitude: 64 deg N). Wood fragments of ancient Metasequoia sp. trees mixed into the crater facies during kimberlite emplacement were recovered from the Ekati and Diavik diamond mines. Wood recovered from the Ekati "Panda" pipe, which has been dated using Rb-Sr age determination at 53.3 +/- 0.6 million years, is unique in that it exhibits extremely low vitrinite reflectance values, comparable to that of modern near-surface peats. The implication is that the wood has undergone minimal thermal or compressional alteration, thus preserving the geochemical signatures originally formed during growth. Ring width measurements representing over 100 years of climate data show congruence between multiple samples, thus enabling the development of a floating master chronology. Patterns contained in this chronology are of particular interest as the early Eocene was characterized by a period of unusual warming that has been compared to modern day climate change. Wood cellulose does not exchange atoms with its surroundings after formation, making it an ideal candidate for stable isotope analysis once it has been separated from associated whole-wood components. A robotic micromilling device was used to collect whole wood samples of latewood from annual tree rings. The α-cellulose in the samples will be isolated and analyzed for δ13C and δ18O, generating a 34-year floating chronology that can be used to reconstruct decadal scale temperature and humidity patterns. Successful application of this technique suggests that a longer Eocene chronology, using additional wood samples recovered from the Panda pipe as well as samples from neighbouring pipes in the Lac de Gras region, can be developed.

  20. A Jurassic Shock-Aftershock Earthquake Sequence Recorded by Small Clastic Pipes and Dikes within Dune Cross-Strata, Zion National Park, Utah

    NASA Astrophysics Data System (ADS)

    Loope, D. B.; Zlotnik, V. A.; Kettler, R. M.; Pederson, D. T.

    2012-12-01

    Eolian sandstones of south-central and southeast Utah contain large volumes of contorted cross-strata that have long been recognized as products of liquefaction caused by seismic shaking. Unlike most sites where Navajo Sandstone is exposed, in Zion National Park (southwestern Utah), the Navajo contains very, very few contorted strata. We have, however, mapped the distribution of more than 1,000 small-scale, vertical pipes and dikes in uncontorted cross-strata of the Navajo at two small study sites in Zion. Pipes are 2-5 cm in diameter and up to 3 m long; dikes are ~6 cm wide. Clusters of the water-escape structures lie directly above and below numerous, near-horizontal bounding surfaces. Dikes are restricted to the wind-ripple strata that lie above the bounding surfaces. Pipes are common both above and below the bounding surfaces. In map view, most pipes are arranged in lines. Near the bounding surfaces, pipes merge upward with shallow dikes trending parallel to the lines of pipes. Pipes formed in grainflows—homogeneous, well-sorted sand lacking cohesion. Dikes formed above the bounding surface, in more-cohesive, poorly sorted, wind-ripple strata. As liquefaction began, expansion of subsurface sand caused spreading within the unliquified (capping) beds near the land surface. Dikes intruded cracks in the wind-ripple strata, and pipes rose from the better-sorted sand to interdune surfaces, following trends of cracks. Because the wind-ripple strata had low cohesive strength, a depression formed around each rupture, and ejected sand built upward to a flat-topped surface rather than forming the cone of a classic sand volcano. In one 3 m2 portion of the map area, a cluster of about 20 pipes and dikes, many with truncated tops, record eight stratigraphically distinct seismic events. The large dunes that deposited the Navajo cross-strata likely moved ~1m/yr. When, in response to seismic shaking, a few liters of fluidized sand erupted onto the lowermost portion of the dune lee slope through a pipe, the erupted sand dried and was buried by climbing wind-ripple strata as the large dune continued to advance downwind. The mapped cluster recording eight distinct seismic events lies within thin-laminated sediment that was deposited by wind ripples during 1 m (~ 1 year) of southeastward dune migration. We conclude that the small pipes and dikes of our study sites are products of numerous >MM 5 earthquakes, some of which recurred at intervals of less than 2 months. We interpret one small cluster of pipes and dikes with well-defined upward terminations as a distinct shock-aftershock sequence. Because the largest modern earthquakes can produce surface liquefaction only up to about 175 km from their epicenters, the Jurassic epicenters must have been well within that distance. The tendency of modern plate boundaries to produce high-frequency aftershocks suggests that the epicenter for this Jurassic sequence lay to the southwest, within the plate boundary zone (not within continental rocks to the east). As eolian dunes steadily migrate over interdune surfaces underlain by water-saturated dune cross-strata, the thin, distinct laminae produced by the wind ripples that occupy dune toes can faithfully record high-frequency seismic events.

  1. NoScale - Characterisation of thermal deep groundwater for the prevention of scaling and corrosion in geothermal plants

    NASA Astrophysics Data System (ADS)

    Haslinger, Edith; Goldbrunner, Johann; Dietzel, Martin; Leis, Albrecht; Boch, Ronny; Knauss, Ralf; Hippler, Dorothee; Shirbaz, Andrea; Fröschl, Heinz; Wyhlidal, Stefan; Plank, Otmar; Gold, Marlies; Elster, Daniel

    2017-04-01

    During the exploitation of thermal water for the use in a geothermal plant a series of hydrochemical reactions such as solution and precipitation processes (scaling) or corrosion processes can be caused by pressure and temperature changes and degassing of the thermal water. Operators of hydrogeothermal plants are often confronted with precipitations in water-bearing parts of their plant, such as heat exchangers and pipes, which result in considerable costs for cleaning or remediation or the use of inhibitors. In the worst case, scaling and corrosion can lead to the abandonment of the system. The effects of the fluids on the technical facilities of hydrogeothermal plants are usually difficult to predict. This applies in particular to the long-term effects in the exploitation and use as well as the aspect of the reinjection of the fluids. In publications and guides for thermal water use in Austria, it is emphasized that the hydrochemical conditions have to be checked during the operation of geothermal plants, but precise directives and thus guidance for operators as well as a scientific investigations on this topic are almost completely missing today. The aim of the research project NoScale was the assessment of deep thermal water bodies in different geological reservoirs in Austria and Bavaria and therefore different hydrochemical compositions with regard to their scaling and corrosion potential in geothermal use. In the course of parallel chemical and mineralogical laboratory investigations, conclusions were drawn about the effects of thermal water on different technical components of hydrogeothermal plants and on the other hand a data basis for the model simulation of the relevant hydrochemical processes was developed. Subsequently, on the basis of detailed hydrochemical model calculations, possible effects of the use of the thermal waters on the technical components of the geothermal plants were shown. This approach of complex process modeling, detailed laboratory studies and experimental approaches has not been followed in Austria so far. The research results contribute significantly to the increased visibility of potential risks of the exploitation and use of thermal water. Thus, the project NoScale supports the operators of hydrogeothermal plants to assess risks of scaling in corrosion already in the pre-drilling phase, which leads to a much more energy and cost efficient operation.

  2. Vortex Apparatus and Demonstrations

    ERIC Educational Resources Information Center

    Shakerin, Said

    2010-01-01

    Vortex flow, from millimeter to kilometer in scale, is important in many scientific and technological areas. Examples are seen in water strider locomotion, from industrial pipe flow (wastewater treatment) to air traffic control (safe distance between aircrafts on a runway ready for takeoff) to atmospheric studies. In this paper, we focus on a…

  3. Effects of Urban Stream Burial on Organic Matter Dynamics and Reach Scale Nitrate Retention

    EPA Science Inventory

    Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO3-) by eliminating primar...

  4. OTEC cold water pipe design for problems caused by vortex-excited oscillations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffin, O. M.

    1980-03-14

    Vortex-excited oscillations of marine structures result in reduced fatigue life, large hydrodynamic forces and induced stresses, and sometimes lead to structural damage and to diestructive failures. The cold water pipe of an OTEC plant is nominally a bluff, flexible cylinder with a large aspect ratio (L/D = length/diameter), and is likely to be susceptible to resonant vortex-excited oscillations. The objective of this report is to survey recent results pertaining to the vortex-excited oscillations of structures in general and to consider the application of these findings to the design of the OTEC cold water pipe. Practical design calculations are given asmore » examples throughout the various sections of the report. This report is limited in scope to the problems of vortex shedding from bluff, flexible structures in steady currents and the resulting vortex-excited oscillations. The effects of flow non-uniformities, surface roughness of the cylinder, and inclination to the incident flow are considered in addition to the case of a smooth cyliner in a uniform stream. Emphasis is placed upon design procedures, hydrodynamic coefficients applicable in practice, and the specification of structural response parameters relevant to the OTEC cold water pipe. There are important problems associated with in shedding of vortices from cylinders in waves and from the combined action of waves and currents, but these complex fluid/structure interactions are not considered in this report.« less

  5. Fatigue life calculation of desuperheater for solving pipe cracking issue using finite element method (FEM) software

    NASA Astrophysics Data System (ADS)

    Kumar, Aravinda; Singh, Jeetendra Kumar; Mohan, K.

    2012-06-01

    Desuperheater assembly experiences thermal cycling in operation by design. During power plant's start up, load change and shut down, thermal gradient is highest. Desuperheater should be able to handle rapid ramp up or ramp down of temperature in these operations. With "hump style" two nozzle desuperheater, cracks were appearing in the pipe after only few cycles of operation. From the field data, it was clear that desuperheater is not able to handle disproportionate thermal expansion happening in the assembly during temperature ramp up and ramp down in operation and leading to cracks appearing in the piping. Growth of thermal fatigue crack is influenced by several factors including geometry, severity of thermal stress and applied mechanical load. This paper seeks to determine cause of failure of two nozzle "hump style" desuperheater using Finite Element Method (FEM) simulation technique. Thermal stress simulation and fatigue life calculation were performed using commercial FEA software "ANSYS" [from Ansys Inc, USA]. Simulation result showed that very high thermal stress is developing in the region where cracks are seen in the field. From simulation results, it is also clear that variable thermal expansion of two nozzle studs is creating high stress at the water manifold junction. A simple and viable solution is suggested by increasing the length of the manifold which solved the cracking issues in the pipe.

  6. NaK Variable Conductance Heat Pipe for Radioisotope Stirling Systems

    NASA Technical Reports Server (NTRS)

    Tarau, Calin; Anderson, William G.; Walker, Kara

    2008-01-01

    In a Stirling radioisotope power system, heat must continually be removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides most of this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending use of that convertor for the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) was designed to allow multiple stops and restarts of the Stirling convertor. In the design of the VCHP for the Advanced Stirling Radioisotope Generator, the VCHP reservoir temperature can vary between 40 and 120 C. While sodium, potassium, or cesium could be used as the working fluid, their melting temperatures are above the minimum reservoir temperature, allowing working fluid to freeze in the reservoir. In contrast, the melting point of NaK is -12 C, so NaK can't freeze in the reservoir. One potential problem with NaK as a working fluid is that previous tests with NaK heat pipes have shown that NaK heat pipes can develop temperature non-uniformities in the evaporator due to NaK's binary composition. A NaK heat pipe was fabricated to measure the temperature non-uniformities in a scale model of the VCHP for the Stirling Radioisotope system. The temperature profiles in the evaporator and condenser were measured as a function of operating temperature and power. The largest delta T across the condenser was 2S C. However, the condenser delta T decreased to 16 C for the 775 C vapor temperature at the highest heat flux applied, 7.21 W/ square cm. This decrease with increasing heat flux was caused by the increased mixing of the sodium and potassium in the vapor. This temperature differential is similar to the temperature variation in this ASRG heat transfer interface without a heat pipe, so NaK can be used as the VCHP working fluid.

  7. A multi-level pore-water sampler for permeable sediments

    USGS Publications Warehouse

    Martin, J.B.; Hartl, K.M.; Corbett, D.R.; Swarzenski, P.W.; Cable, J.E.

    2003-01-01

    The construction and operation of a multi-level piezometer (multisampler) designed to collect pore water from permeable sediments up to 230 cm below the sediment-water interface is described. Multisamplers are constructed from 1 1/2 inch schedule 80 PVC pipe. One-quarter-inch flexible PVC tubing leads from eight ports at variable depths to a 1 1/2 inch tee fitting at the top of the PVC pipe. Multisamplers are driven into the sediments using standard fence-post drivers. Water is pumped from the PVC tubing with a peristaltic pump. Field tests in Banana River Lagoon, Florida, demonstrate the utility of multisamplers. These tests include collection of multiple samples from the permeable sediments and reveal mixing between shallow pore water and overlying lagoon water.

  8. Intermittent Water Supply: Prevalence, Practice, and Microbial Water Quality.

    PubMed

    Kumpel, Emily; Nelson, Kara L

    2016-01-19

    Intermittent water supplies (IWS), in which water is provided through pipes for only limited durations, serve at least 300 million people around the world. However, providing water intermittently can compromise water quality in the distribution system. In IWS systems, the pipes do not supply water for periods of time, supply periods are shortened, and pipes experience regular flow restarting and draining. These unique behaviors affect distribution system water quality in ways that are different than during normal operations in continuous water supplies (CWS). A better understanding of the influence of IWS on mechanisms causing contamination can help lead to incremental steps that protect water quality and minimize health risks. This review examines the status and nature of IWS practices throughout the world, the evidence of the effect of IWS on water quality, and how the typical contexts in which IWS systems often exist-low-income countries with under-resourced utilities and inadequate sanitation infrastructure-can exacerbate mechanisms causing contamination. We then highlight knowledge gaps for further research to improve our understanding of water quality in IWS.

  9. Efficiently-cooled plasmonic amorphous silicon solar cells integrated with a nano-coated heat-pipe plate

    PubMed Central

    Zhang, Yinan; Du, Yanping; Shum, Clifford; Cai, Boyuan; Le, Nam Cao Hoai; Chen, Xi; Duck, Benjamin; Fell, Christopher; Zhu, Yonggang; Gu, Min

    2016-01-01

    Solar photovoltaics (PV) are emerging as a major alternative energy source. The cost of PV electricity depends on the efficiency of conversion of light to electricity. Despite of steady growth in the efficiency for several decades, little has been achieved to reduce the impact of real-world operating temperatures on this efficiency. Here we demonstrate a highly efficient cooling solution to the recently emerging high performance plasmonic solar cell technology by integrating an advanced nano-coated heat-pipe plate. This thermal cooling technology, efficient for both summer and winter time, demonstrates the heat transportation capability up to ten times higher than those of the metal plate and the conventional wickless heat-pipe plates. The reduction in temperature rise of the plasmonic solar cells operating under one sun condition can be as high as 46%, leading to an approximate 56% recovery in efficiency, which dramatically increases the energy yield of the plasmonic solar cells. This newly-developed, thermally-managed plasmonic solar cell device significantly extends the application scope of PV for highly efficient solar energy conversion. PMID:27113558

  10. Efficiently-cooled plasmonic amorphous silicon solar cells integrated with a nano-coated heat-pipe plate.

    PubMed

    Zhang, Yinan; Du, Yanping; Shum, Clifford; Cai, Boyuan; Le, Nam Cao Hoai; Chen, Xi; Duck, Benjamin; Fell, Christopher; Zhu, Yonggang; Gu, Min

    2016-04-26

    Solar photovoltaics (PV) are emerging as a major alternative energy source. The cost of PV electricity depends on the efficiency of conversion of light to electricity. Despite of steady growth in the efficiency for several decades, little has been achieved to reduce the impact of real-world operating temperatures on this efficiency. Here we demonstrate a highly efficient cooling solution to the recently emerging high performance plasmonic solar cell technology by integrating an advanced nano-coated heat-pipe plate. This thermal cooling technology, efficient for both summer and winter time, demonstrates the heat transportation capability up to ten times higher than those of the metal plate and the conventional wickless heat-pipe plates. The reduction in temperature rise of the plasmonic solar cells operating under one sun condition can be as high as 46%, leading to an approximate 56% recovery in efficiency, which dramatically increases the energy yield of the plasmonic solar cells. This newly-developed, thermally-managed plasmonic solar cell device significantly extends the application scope of PV for highly efficient solar energy conversion.

  11. Screening reactor steam/water piping systems for water hammer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffith, P.

    1997-09-01

    A steam/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam bubble collapse induced water hammer, six conditions must be met in order for one to occur. These are: (1) the pipe must be almost horizontal; (2) the subcooling must be greater than 20 C; (3) the L/D must be greatermore » than 24; (4) the velocity must be low enough so that the pipe does not run full, i.e., the Froude number must be less than one; (5) there should be void nearby; (6) the pressure must be high enough so that significant damage occurs, that is the pressure should be above 10 atmospheres. Recommendations on how to avoid this kind of water hammer in both the design and the operation of the reactor system are made.« less

  12. Efficiently-cooled plasmonic amorphous silicon solar cells integrated with a nano-coated heat-pipe plate

    NASA Astrophysics Data System (ADS)

    Zhang, Yinan; Du, Yanping; Shum, Clifford; Cai, Boyuan; Le, Nam Cao Hoai; Chen, Xi; Duck, Benjamin; Fell, Christopher; Zhu, Yonggang; Gu, Min

    2016-04-01

    Solar photovoltaics (PV) are emerging as a major alternative energy source. The cost of PV electricity depends on the efficiency of conversion of light to electricity. Despite of steady growth in the efficiency for several decades, little has been achieved to reduce the impact of real-world operating temperatures on this efficiency. Here we demonstrate a highly efficient cooling solution to the recently emerging high performance plasmonic solar cell technology by integrating an advanced nano-coated heat-pipe plate. This thermal cooling technology, efficient for both summer and winter time, demonstrates the heat transportation capability up to ten times higher than those of the metal plate and the conventional wickless heat-pipe plates. The reduction in temperature rise of the plasmonic solar cells operating under one sun condition can be as high as 46%, leading to an approximate 56% recovery in efficiency, which dramatically increases the energy yield of the plasmonic solar cells. This newly-developed, thermally-managed plasmonic solar cell device significantly extends the application scope of PV for highly efficient solar energy conversion.

  13. Stability of florfenicol in drinking water.

    PubMed

    Hayes, John M; Eichman, Jonathan; Katz, Terry; Gilewicz, Rosalia

    2003-01-01

    Florfenicol, a broad-spectrum antibiotic, is being developed for veterinary application as an oral concentrate intended for dilution with drinking water. When a drug product is dosed via drinking water in a farm setting, a number of variables, including pH, chlorine content, hardness of the water used for dilution, and container material, may affect its stability, leading to a decrease in drug potency. The stability of florfenicol after dilution of Florfenicol Drinking Water Concentrate Oral Solution, 23 mg/mL, with drinking water was studied. A stability-indicating, validated liquid chromatographic method was used to evaluate florfenicol stability at 25 degrees C at 5, 10, and 24 h after dilution. The results indicate that florfenicol is stable under a range of simulated field conditions, including various pipe materials and conditions of hard or soft and chlorinated or nonchlorinated water at low or high pH. Significant degradation (> 10%) was observed only for isolated combinations in galvanized pipes. Analysis indicated that the florfenicol concentration in 8 of the 12 water samples stored in galvanized pipes remained above 90% of the initial concentration (100 mg/L) for 24 h after dilution.

  14. Non-Intrusive Velocity Measurements with MTV During DCC Event in the HTTF

    NASA Technical Reports Server (NTRS)

    Andre, M. A.; Bardet, P. M.; Cadell, S. R.; Woods, B.; Burns, R. A.; Danehy, P. M.

    2017-01-01

    Velocity profiles are measured using molecular tagging velocimetry (MTV) in the high temperature test facility (HTTF) at Oregon State University during a depressurized conduction cooldown (DCC) event. The HTTF is a quarter scale electrically heated nuclear reactor simulator designed to replicate various accident scenarios. During a DCC, a double ended guillotine break results in the reactor pressure vessel (RPV) depressurizing into the reactor cavity and ultimately leading to air ingress in the reactor core (lock-exchange and gas diffusion). It is critical to understand the resulting buoyancy-driven flow to characterize the reactor self-cooling capacity through natural circulation. During tests conducted at ambient pressure and temperature, the RPV containing helium is opened (via the hot and cold legs) to a large vessel filled with nitrogen to simulate the atmosphere. The velocity profile on the hot leg pipe centerline is recorded at 10 Hz with MTV based on NO tracers. The precision of the velocimetry was measured to be 0.02 m/s in quiescent flow prior to the tests. A helium flow from the RPV is initially observed in the top quarter of the pipe. During the first 20 seconds of the event, helium flows out of the RPV with a maximum velocity below 2 m/s. The velocity profile transitions from parabolic to linear in character and decays slowly over the rest of the recording; peak velocities of 0.2 m/s are observed after 30 min. A counter-flow of nitrogen is also observed intermittently, which occurs at lower velocities (>0.1 m/s).

  15. [A "historical" case of lead poisoning via drinking water: diagnostic and therapeutic issues].

    PubMed

    Testud, F; Girtanner-Brunel, L; Péaud, P Y; Serpollet, G; Duchen, C

    2001-12-01

    It is likely that lead poisoning via drinking water is often overlooked because of its supposed rarity and nonspecific early symptoms, which result in delayed management. One case of severe lead poisoning via drinking water is reported. The diagnosis was long missed and a particularly long chelating treatment was required. The clinical features included lead colic, a Burton's lead line, anemia, polyneuritis and arterial hypertension. Eighteen courses of calcium EDTA were required to obtain 'biological recovery'. The poisoning was linked to a very long water supply lead pipe and potomania secondary to alcohol withdrawal. This case report illustrates how difficult the early recognition of lead poisoning can be, and underlines the need to inquire about a toxic aetiology, particularly via the environment, of otherwise unexplained pathological conditions.

  16. Heat pipes for sodium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Hartenstine, John R.

    1989-08-01

    The objective of this program was to develop a variable conductance heat pipe (VCHP) for the thermal management of sodium-sulfur batteries. The VCHP maintains the sodium sulfur battery within a specified temperature rise limit (20 C) while the battery discharges a thermal load from 0 watts to 500 watts. A preliminary full scale thermal management design was developed for the sodium-sulfur battery, incorporating the VCHPs and supporting integration hardware. The feasibility of the VCHPs for this application was proved by test. The VCHP developed in Phase 1 utilized titanium as the heat pipe envelope material, and cesium as the heat pipe working fluid. The wick structure was axial grooves. Analysis and test indicate that the VCHP can provide the passive thermal control necessary for the sodium-sulfur battery. Test data show that with the heat input from Q = 0 watts to Q = 500 watts, the VCHP evaporator temperature increased from 350 C to 385 C. The temperature control range was higher than predicted due to working fluid vapor diffusion into the noncondensible gas and thermal axial conduction into the VCHP reservoir. Analysis has shown that by utilizing VCHPs for passive temperature control, the sodium-sulfur battery cells will have a lower axial delta-T during discharge than a current louver design. The VCHP thermal management package has the potential to be used in geosynchronous earth orbits (GEO) and low earth orbits (LEO).

  17. Treatment of iron(II)-rich acid mine water with limestone and oxygen.

    PubMed

    Mohajane, G B; Maree, J P; Panichev, N

    2014-01-01

    The main components of acid mine water are free acid, sulphate, and Fe²⁺. Limestone is the most cost-effective alkali that can be used for neutralization. The purpose of this investigation was to identify conditions where Fe²⁺ is removed with limestone and simultaneously oxidized with oxygen to Fe³⁺, in a polyvinyl chloride pipe under pressure. Gypsum scaling is prevented by passing rubber balls through the pipe of the so-called Oxygen-Pipe-Neutralization (OPeN) process pilot plant. Two synthetic waters were treated: (A) acid mine water containing 123 mg L⁻¹ Fe²⁺ representing gold mine water, and (B) acid mine water containing 6,032 mg L⁻¹ Fe²⁺ representing coal mine water. Batch studies were carried out in a pipe reactor and showed that the rate of Fe²⁺ oxidation depended on the Fe²⁺ concentration, oxygen pressure, amount of recycled sludge, limestone dosage and the mixing rate. Continuous studies in an OPeN process pilot plant resulted in 100% removal of total acidity from synthetic coal mine water and a 98% removal from synthetic gold mine water. Fe²⁺ was removed completely as precipitated Fe(OH)₃ from both synthetic coal and gold mine water at around pH 7 at 200 and 100 kPa oxygen pressure, respectively.

  18. Smart Pipe System for a Shipyard 4.0

    PubMed Central

    Fraga-Lamas, Paula; Noceda-Davila, Diego; Fernández-Caramés, Tiago M.; Díaz-Bouza, Manuel A.; Vilar-Montesinos, Miguel

    2016-01-01

    As a result of the progressive implantation of the Industry 4.0 paradigm, many industries are experimenting a revolution that shipyards cannot ignore. Therefore, the application of the principles of Industry 4.0 to shipyards are leading to the creation of Shipyards 4.0. Due to this, Navantia, one of the 10 largest shipbuilders in the world, is updating its whole inner workings to keep up with the near-future challenges that a Shipyard 4.0 will have to face. Such challenges can be divided into three groups: the vertical integration of production systems, the horizontal integration of a new generation of value creation networks, and the re-engineering of the entire production chain, making changes that affect the entire life cycle of each piece of a ship. Pipes, which exist in a huge number and varied typology on a ship, are one of the key pieces, and its monitoring constitutes a prospective cyber-physical system. Their improved identification, traceability, and indoor location, from production and through their life, can enhance shipyard productivity and safety. In order to perform such tasks, this article first conducts a thorough analysis of the shipyard environment. From this analysis, the essential hardware and software technical requirements are determined. Next, the concept of smart pipe is presented and defined as an object able to transmit signals periodically that allows for providing enhanced services in a shipyard. In order to build a smart pipe system, different technologies are selected and evaluated, concluding that passive and active RFID (Radio Frequency Identification) are currently the most appropriate technologies to create it. Furthermore, some promising indoor positioning results obtained in a pipe workshop are presented, showing that multi-antenna algorithms and Kalman filtering can help to stabilize Received Signal Strength (RSS) and improve the overall accuracy of the system. PMID:27999392

  19. Eddy Current Testing with Giant Magnetoresistance (GMR) Sensors and a Pipe-Encircling Excitation for Evaluation of Corrosion under Insulation

    PubMed Central

    Bailey, Joseph; Hunze, Arvid

    2017-01-01

    This work investigates an eddy current-based non-destructive testing (NDT) method to characterize corrosion of pipes under thermal insulation, one of the leading failure mechanisms for insulated pipe infrastructure. Artificial defects were machined into the pipe surface to simulate the effect of corrosion wall loss. We show that by using a giant magnetoresistance (GMR) sensor array and a high current (300 A), single sinusoidal low frequency (5–200 Hz) pipe-encircling excitation scheme it is possible to quantify wall loss defects without removing the insulation or weather shield. An analysis of the magnetic field distribution and induced currents was undertaken using the finite element method (FEM) and analytical calculations. Simple algorithms to remove spurious measured field variations not associated with defects were developed and applied. The influence of an aluminium weather shield with discontinuities and dents was ascertained and found to be small for excitation frequency values below 40 Hz. The signal dependence on the defect dimensions was analysed in detail. The excitation frequency at which the maximum field amplitude change occurred increased linearly with the depth of the defect by about 3 Hz/mm defect depth. The change in magnetic field amplitude due to defects for sensors aligned in the azimuthal and radial directions were measured and found to be linearly dependent on the defect volume between 4400–30,800 mm3 with 1.2 × 10−3−1.6 × 10−3 µT/mm3. The results show that our approach is well suited for measuring wall loss defects similar to the defects from corrosion under insulation. PMID:28956855

  20. Smart Pipe System for a Shipyard 4.0.

    PubMed

    Fraga-Lamas, Paula; Noceda-Davila, Diego; Fernández-Caramés, Tiago M; Díaz-Bouza, Manuel A; Vilar-Montesinos, Miguel

    2016-12-20

    As a result of the progressive implantation of the Industry 4.0 paradigm, many industries are experimenting a revolution that shipyards cannot ignore. Therefore, the application of the principles of Industry 4.0 to shipyards are leading to the creation of Shipyards 4.0. Due to this, Navantia, one of the 10 largest shipbuilders in the world, is updating its whole inner workings to keep up with the near-future challenges that a Shipyard 4.0 will have to face. Such challenges can be divided into three groups: the vertical integration of production systems, the horizontal integration of a new generation of value creation networks, and the re-engineering of the entire production chain, making changes that affect the entire life cycle of each piece of a ship. Pipes, which exist in a huge number and varied typology on a ship, are one of the key pieces, and its monitoring constitutes a prospective cyber-physical system. Their improved identification, traceability, and indoor location, from production and through their life, can enhance shipyard productivity and safety. In order to perform such tasks, this article first conducts a thorough analysis of the shipyard environment. From this analysis, the essential hardware and software technical requirements are determined. Next, the concept of smart pipe is presented and defined as an object able to transmit signals periodically that allows for providing enhanced services in a shipyard. In order to build a smart pipe system, different technologies are selected and evaluated, concluding that passive and active RFID (Radio Frequency Identification) are currently the most appropriate technologies to create it. Furthermore, some promising indoor positioning results obtained in a pipe workshop are presented, showing that multi-antenna algorithms and Kalman filtering can help to stabilize Received Signal Strength (RSS) and improve the overall accuracy of the system.

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