Science.gov

Sample records for corrugated pipe culverts

  1. 78 FR 5715 - Construction and Maintenance-Culvert Pipe Selection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ...to ensure that States shall have the autonomy to determine culvert and storm sewer...Section 1525 of MAP-21, ``State Autonomy for Culvert Pipe Selection,'' requires...to ensure that States shall have the autonomy to determine culvert and storm...

  2. Corrugated pipe adhesive applicator apparatus

    DOEpatents

    Shirey, R.A.

    1983-06-14

    Apparatus for coating selected portions of the troughs of a corrugated pipe with an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough. 4 figs.

  3. Corrugated Pipe as a Beam Dechirper

    SciTech Connect

    Bane, K.L.F.; Stupakov, G.; /SLAC

    2012-04-20

    We have studied the use of a metallic pipe with small corrugations for the purpose of passively dechirping, through its wakefield, a short, intense electron bunch. The corrugated pipe is attractive for this purpose because its wake: (i) has near maximal possible amplitude for a given aperture and (ii) has a relatively large oscillation wave length, even when the aperture is small. We showed how the corrugated structure can satisfy dechirping requirements encountered in the NGLS project at LBNL. We found that a linear chirp of -40 MeV/mm can be induced by an NGLS-like beam, by having it pass through a corrugated, metallic pipe of radius 3 mm, length 8.2 m, and corrugation parameters full depth 450 {mu}m and period 1000 {mu}m. This structure is about 15 times as effective in the role of dechirper as an S-band accelerator structure used passively.

  4. Velocity Field Characteristics at the Inlet to a Pipe Culvert

    NASA Astrophysics Data System (ADS)

    Kolerski, Tomasz; Wielgat, Pawe?

    2014-12-01

    A poorly designed culvert inlet structure causes scouring, which can lead to the collapse of the culvert and significant damage to the neighboring land. A set of laboratory tests was evaluated to examine velocity distribution at the culvert inlet. A three-dimensional acoustic Doppler velocimeter was used to measure instantaneous flow velocity upstream of the culvert. The analysis of mean velocities, turbulence strength, and Reynolds stresses was performed to understand the flow structure near the culvert entrance.

  5. Stability of steady flow through an axially corrugated pipe

    NASA Astrophysics Data System (ADS)

    Loh, S. A.; Blackburn, H. M.

    2011-11-01

    The linear stability of steady flow in pipes with circular cross-section and sinusoidal axial variation in diameter is studied by finding global eigenmodes with axial wavelength commensurate with that of the wall corrugation, chosen to be equal to one pipe mean radius. The maximum peak-to-peak height of corrugation considered is approximately 8% of the mean diameter. At low corrugation amplitude and at low Reynolds numbers, the base flow remains attached to the wall, while at larger amplitudes and Reynolds numbers, an axisymmetric separation bubble forms within the corrugation. For all Reynolds numbers considered, flows remain stable to axisymmetric perturbations, but become unstable to standing-wave modes of low azimuthal wavenumber, with critical Reynolds number first falling, then increasing with increasing corrugation height. Both attached and separated flows exhibit similar types of instability modes, which in the case of separated flow are most energetic near the reattachment line of the base flow. The leading instability modes consist of counter-rotating vortices situated near the pipe wall.

  6. Terahertz Radiation from a Pipe with Small Corrugations

    SciTech Connect

    Bane, K.L.F.; Stupakov, G.; /SLAC

    2012-01-26

    We have studied through analytical and numerical methods the use of a relativistic electron bunch to drive a metallic beam pipe with small corrugations for the purpose of generating terahertz radiation. For the case of a pipe with dimensions that do not change along its length, we have shown that - with reasonable parameters - one can generate a narrow-band radiation pulse with frequency {approx}1 THz, and total energy of a few milli-Joules. The pulse length tends to be on the order of tens of picoseconds. We have also shown that, if the pipe radius is tapered along its length, the generated pulse will end up with a frequency chirp; if the pulse is then made to pass through a compressor, its final length can be reduced to a few picoseconds and its peak power increased to 1 GW. We have also shown that wall losses tend to be significant and need to be included in the structure design.

  7. Surface Impedance Formalism for a Metallic Beam Pipe with Small Corrugations

    SciTech Connect

    Stupakov, G.; Bane, K.L.F.; /SLAC

    2012-08-30

    A metallic pipe with wall corrugations is of special interest in light of recent proposals to use such a pipe for the generation of terahertz radiation and for energy dechirping of electron bunches in free electron lasers. In this paper we calculate the surface impedance of a corrugated metal wall and show that it can be reduced to that of a thin layer with dielectric constant {epsilon} and magnetic permeability {mu}. We develop a technique for the calculation of these constants, given the geometrical parameters of the corrugations. We then calculate, for the specific case of a round metallic pipe with small corrugations, the frequency and strength of the resonant mode excited by a relativistic beam. Our analytical results are compared with numerical simulations, and are shown to agree well.

  8. Flow noise in a corrugated pipe in terms of the theory of instability waves

    NASA Astrophysics Data System (ADS)

    Kopiev, V. F.; Mironov, M. A.; Yakovets, M. A.

    2015-09-01

    An air flow through a pipe with a corrugated inner surface is accompanied by the generation of a tone (multitone), i.e., coherent, acoustic signal. The main processes giving rise to such a generation include the forced excitation of the active medium in the resonator (the pipe) and the feedback, which leads to nonlinear amplification of one or several resonator harmonics because of the nonlinear competition of waves. The medium in the pipe becomes active owing to the processes that accompany the air flow about the corrugated wall. The purpose of the present study is to provide qualitative explanations based on a simple example for the possibility of multitone sound generation, as well as for the known experimental data.

  9. Simulation and analysis on ultrasonic testing for the cement grouting defects of the corrugated pipe

    SciTech Connect

    Qingbang, Han; Ling, Chen; Changping, Zhu

    2014-02-18

    The defects exist in the cement grouting process of prestressed corrugated pipe may directly impair the bridge safety. In this paper, sound fields propagation in concrete structures with corrugated pipes and the influence of various different defects are simulated and analyzed using finite element method. The simulation results demonstrate a much complex propagation characteristic due to multiple reflection, refraction and scattering, where the scattering signals caused by metal are very strong, while the signals scattered by an air bubble are weaker. The influence of defect both in time and frequency domain are found through deconvolution treatment. In the time domain, the deconvolution signals correspond to larger defect display a larger head wave amplitude and shorter arrive time than those of smaller defects; in the frequency domain, larger defect also shows a stronger amplitude, lower center frequency and lower cutoff frequency.

  10. Culvert Capacity and Passability

    E-print Network

    Walter, M.Todd

    runoff with green infrastructure · Build demonstration sites Catskill Mountain stream #12; Replace poor (Vedachalem and Riha, 2013) Rt. 7, Ancram #12;Cost of Culvert Mitigation Better culvert design can raise culverts with better designed culverts DPW needs to be supported if they decide that a larger culvert

  11. Heat output and maximum heat transfer of heat pipes with continuous corrugated wicks

    SciTech Connect

    Afanas'ev, B.A.; Smirnov, G.F.; Vinogradova, E.P.

    1986-07-01

    This paper describes experiments to study heat transfer with vapor formation in corrugated metal foil wicks. The heat transfer in the evaporation zone of the heat pipe was modeled using an approved technique. In parallel with the study of heat transfer the authors determined the limiting heat flux from the intense growth of the heater surface temperature. The test results on limiting heat flux obtained for various modules and structure strip widths at zero level of heat transfer relative to the heater surface are shown. It follows from analysis of these data that an increase of structure strip width reduces the limiting heat-flux density. A reduction of the codule leads to the same result.

  12. 1. View east at west facade of culvert outlet headwall, ...

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

    1. View east at west facade of culvert outlet headwall, above which part of the canal bank has been removed. Foreground to background: streambed and coffer dam (mound in center) that was used in dewatering the culvert; intake pipes (extreme left and right) for dewatering pumps; deteriorated culvert outlet headwall with upper portion of wall fallen away; horizontal masonry cutoff wall extending above the culvert outlet partially up the canal bank (cutoff wall was exposed by removal of part of canal bank); towpath at top of canal bank. - Delaware & Raritan Canal, Six Mile Run Culvert, .2 mile South of Blackwells Mills Road, East Millstone, Somerset County, NJ

  13. Experimental demonstration of energy-chirp control in relativistic electron bunches using a corrugated pipe.

    PubMed

    Emma, P; Venturini, M; Bane, K L F; Stupakov, G; Kang, H-S; Chae, M S; Hong, J; Min, C-K; Yang, H; Ha, T; Lee, W W; Park, C D; Park, S J; Ko, I S

    2014-01-24

    The first experimental study is presented of a corrugated wall device that uses wakefields to remove a linear energy correlation in a relativistic electron beam (a "dechirper"). Time-resolved measurements of both longitudinal and transverse wakefields of the device are presented and compared with simulations. This study demonstrates the feasibility to employ a dechirper for precise control of the beam phase space in the next generation of free-electron-lasers. PMID:24484143

  14. North portal of Culvert No. 1309, Fifteen Mile Creek Culvert, ...

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

    North portal of Culvert No. 1309, Fifteen Mile Creek Culvert, looking southeast. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  15. Culvert No. 1309, Fifteen Mile Creek Culvert, north portal, looking ...

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

    Culvert No. 1309, Fifteen Mile Creek Culvert, north portal, looking east. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  16. Application of a multistate model to estimate culvert effects on movement of small fishes

    USGS Publications Warehouse

    Norman, J.R.; Hagler, M.M.; Freeman, Mary C.; Freeman, B.J.

    2009-01-01

    While it is widely acknowledged that culverted road-stream crossings may impede fish passage, effects of culverts on movement of nongame and small-bodied fishes have not been extensively studied and studies generally have not accounted for spatial variation in capture probabilities. We estimated probabilities for upstream and downstream movement of small (30-120 mm standard length) benthic and water column fishes across stream reaches with and without culverts at four road-stream crossings over a 4-6-week period. Movement and reach-specific capture probabilities were estimated using multistate capture-recapture models. Although none of the culverts were complete barriers to passage, only a bottomless-box culvert appeared to permit unrestricted upstream and downstream movements by benthic fishes based on model estimates of movement probabilities. At two box culverts that were perched above the water surface at base flow, observed movements were limited to water column fishes and to intervals when runoff from storm events raised water levels above the perched level. Only a single fish was observed to move through a partially embedded pipe culvert. Estimates for probabilities of movement over distances equal to at least the length of one culvert were low (e.g., generally ???0.03, estimated for 1-2-week intervals) and had wide 95% confidence intervals as a consequence of few observed movements to nonadjacent reaches. Estimates of capture probabilities varied among reaches by a factor of 2 to over 10, illustrating the importance of accounting for spatially variable capture rates when estimating movement probabilities with capture-recapture data. Longer-term studies are needed to evaluate temporal variability in stream fish passage at culverts (e.g., in relation to streamflow variability) and to thereby better quantify the degree of population fragmentation caused by road-stream crossings with culverts. ?? American Fisheries Society 2009.

  17. Acoustical studies on corrugated tubes

    NASA Astrophysics Data System (ADS)

    Balaguru, Rajavel

    Corrugated tubes and pipes offer greater global flexibility combined with local rigidity. They are used in numerous engineering applications such as vacuum cleaner hosing, air conditioning systems of aircraft and automobiles, HVAC control systems of heating ducts in buildings, compact heat exchangers, medical equipment and offshore gas and oil transportation flexible riser pipelines. Recently there has been a renewed research interest in analyzing the flow through a corrugated tube to understand the underlying mechanism of so called whistling, although the whistling in such a tube was identified in early twentieth century. The phenomenon of whistling in a corrugated tube is interesting because an airflow through a smooth walled tube of similar dimensions will not generate any whistling tones. Study of whistling in corrugated tubes is important because, it not only causes an undesirable noise problem but also results in flow-acoustic coupling. Such a coupling can cause significant structural vibrations due to flow-acoustic-structure interaction. This interaction would cause flow-induced vibrations that could result in severe damage to mechanical systems having corrugated tubes. In this research work, sound generation (whistling) in corrugated tubes due to airflow is analyzed using experimental as well as Computational Fluid Dynamics-Large Eddy Simulation (CFD-LES) techniques. Sound generation mechanisms resulting in whistling have been investigated. The whistling in terms of frequencies and sound pressure levels for different flow velocities are studied. The analytical and experimental studies are carried out to understand the influence of various parameters of corrugated tubes such as cavity length, cavity width, cavity depth, pitch, Reynolds numbers and number of corrugations. The results indicate that there is a good agreement between theoretically calculated, computationally predicted and experimentally measured whistling frequencies and sound pressure levels generated by flow through corrugated tubes. The computational studies are also extended for noise control through design of corrugated tubes such as design of leading and trailing edge spoilers, slanted walls for the cavities and presence of solid strip in the cavities of corrugations. Applications of this work to improve acoustical design of corrugated tubes are also discussed.

  18. ECOLOGICAL CRITERIA FOR PRIORITIZATION OF CULVERT REPLACEMENT

    EPA Science Inventory

    Culvert passage issues are gaining national and international focus, because they are implicated in the decline of particular species and in the more general loss of biodiversity in freshwater ecosystems. In the Pacific Northwest, inadequate fish passage at culverts is recognized...

  19. 3. View southwest at dewatered culvert outlet headwall, with part ...

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

    3. View southwest at dewatered culvert outlet headwall, with part of canal bank removed in back (left) of headwall. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  20. Wakefield potentials of corrugated structures

    NASA Astrophysics Data System (ADS)

    Novokhatski, A.

    2015-10-01

    A corrugated structure, which is used in "dechirper" devices, is usually a pipe or two plates with small corrugations (bumps) on the walls. There is a good single-mode description of the wake potentials excited by a relativistic bunch if the wave length of the mode is much longer than the distance between the bumps in the pipe. However, ultrashort bunches, which are now used in free electron lasers, excite much higher frequency fields and the corresponding wake potentials will be very different from the single-mode description. We have made analyses of these wake potentials based on a numerical solution of Maxwell's equations. It was confirmed that the behavior of the wakefields of ultrashort bunches in corrugated structures is not much different from the fields excited usually in accelerating structures where the wake potentials are described by the exponential function. For a practical application we present results for the SLAC "dechirper." We also carried out calculations for a similar device, that was installed and measured at the Pohang Accelerator Laboratory, Korea. We find very good agreement with the experimental results.

  1. 4. View southeast at culvert outlet with part of the ...

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

    4. View southeast at culvert outlet with part of the canal bank removed. Right to left: dewatered streambed and coffer dam; tops of culvert barrels and curved wingwalls exposed; horizontal masonry cutoff wall partially up the canal bank. - Delaware & Raritan Canal, Six Mile Run Culvert, .2 mile South of Blackwells Mills Road, East Millstone, Somerset County, NJ

  2. Birefringent corrugated waveguide

    DOEpatents

    Moeller, Charles P. (Del Mar, CA)

    1990-01-01

    A corrugated waveguide having a circular bore and noncircularly symmetric corrugations, and preferably elliptical corrugations, provides birefringence for rotation of polarization in the HE.sub.11 mode. The corrugated waveguide may be fabricated by cutting circular grooves on a lathe in a cylindrical tube or rod of aluminum of a diameter suitable for the bore of the waveguide, and then cutting an approximation to ellipses for the corrugations using a cutting radius R.sub.0 from the bore axis that is greater than the bore radius, and then making two circular cuts using a radius R.sub.1 less than R.sub.0 at centers +b and -b from the axis of the waveguide bore. Alternatively, stock for the mandrel may be formed with an elliptical transverse cross section, and then only the circular grooves need be cut on a lathe, leaving elliptical corrugations between the grooves. In either case, the mandrel is first electroplated and then dissolved leaving a corrugated waveguide with noncircularly symmetric corrugations. A transition waveguide is used that gradually varies from circular to elliptical corrugations to couple a circularly corrugated waveguide to an elliptically corrugated waveguide.

  3. Curved cap corrugated sheet

    NASA Technical Reports Server (NTRS)

    Davis, R. C.; Bales, T. T.; Royster, D. M.; Jackson, L. R. (inventors)

    1984-01-01

    The report describes a structure for a strong, lightweight corrugated sheet. The sheet is planar or curved and includes a plurality of corrugation segments, each segment being comprised of a generally U-shaped corrugation with a part-cylindrical crown and cap strip, and straight side walls and with secondary corrugations oriented at right angles to said side walls. The cap strip is bonded to the crown and the longitudinal edge of said cap strip extends beyond edge at the intersection between said crown and said side walls. The high strength relative to weight of the structure makes it desirable for use in aircraft or spacecraft.

  4. Sediment Transport through Road Culverts Retrofit for Fish Passage

    NASA Astrophysics Data System (ADS)

    Lang, M.; Cashman, E.; Siegfried, L.; Smith, W. J.; Dillon, A.

    2007-12-01

    A critical component of watershed restoration includes improved mobility within the watershed for fish and other aquatic organisms. At the large scale, this effort includes installation of fish ladders around dams and at smaller scales replacement or retrofit of road culverts or installation of roughened channels to mitigate steep channel slopes. A project to quantify changes in culvert hydraulic performance and hydraulic capacity for three culvert shapes and six fish passage retrofit designs was initiated in June 2005. In 2007, laboratory physical model experiments were conducted to evaluate sediment transport and trapping characteristics of these designs over a range of flows. Generally, experimental results indicate trapped sediment in culverts retrofit to improve fish passage decreases the effectiveness of the retrofit due to sediment deposition in areas with lower velocities (where fish can rest). Other observations include: 1. Trapped sediment reduced the effective culvert barrel roughness and, thus, decreased water depths and increased velocities through the culvert, compared to clear water experiments with the retrofit baffles. 2. High flows (culvert barrel water depth/culvert height greater than 0.5) successfully cleared trapped sediment under conditions of minimal transport from upstream 3. Preliminary results indicate moderate flows (culvert barrel water depth/culvert height between 0.25 to 0.5) in combination with moderate sediment feed rates caused the greatest accumulation of trapped sediment These experiments highlight the importance of including sediment accumulation in design and analysis, and potentially impact design recommendations for culverts retrofit for fish passage and other similar fish passage improvement structures.

  5. Corrugated Cardboard Scenery Construction.

    ERIC Educational Resources Information Center

    Wedwick, Daryl M.

    The use of corrugated cardboard in constructing stage scenery is discussed in this paper. In the first section, both the advantages and the problems associated with using the material are discussed, as are ways to avoid problems. The second section of the paper discusses general methods for preparing corrugated materials for set and prop…

  6. Design Automation for Box Culverts Using Web Based Application 

    E-print Network

    Sethi, Manmeetsingh

    2015-02-24

    configuration, precast concrete box culverts with various dimensions are commonly used in the U.S. In some cases, non-standard box culverts are also used, for which the design document has to be produced per project design specification. The design process...

  7. Measurement of peak discharge at culverts by indirect methods

    USGS Publications Warehouse

    Bodhaine, G.L.

    1968-01-01

    This chapter classifies culvert flow into six types, gives discharge equations based on continuity and energy equations, and describes procedures for measuring peak discharges using culverts in the field. Discharge coefficients for a variety of geometries and flow types arc given. Ten examples detail step-by-step computation procedures.

  8. 1. View southeast at northwest facade of dewatered culvert outlet ...

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

    1. View southeast at northwest facade of dewatered culvert outlet headwall, above which part of the canal bank has been removed. Buttresses and upper portion of headwall (above arches) are nineteenth-century additions to the lower, original headwall. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  9. 78 FR 5715 - Construction and Maintenance-Culvert Pipe Selection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ... (39 FR 35152). According to Sec. 635.117(d), as in effect in 1974, Appendix A * * * sets forth the... installations. On September 10, 1976, this section was redesignated as 23 CFR 635.411 (41 FR 36204) and remained.... To implement this provision, the FHWA issued a final rule on November 15, 2006 (71 FR 66450),...

  10. Profiles in garbage: Corrugated boxes

    SciTech Connect

    Miller, C.

    1997-12-01

    Corrugated boxes (also known as old corrugated containers, or OCC) are used to ship products to factories, warehouses, retail stores, offices, and homes. The primary market for OCC is the paperboard industry, which uses OCC for corrugated medium, linerboard, recycled paperboard, and other paper products. In addition, 2.6 million tons of OCC were exported in 1996. OCC provided 37% of the scrap paper that was exported in 1996. Some corrugated boxes can be reused before recycling. Corrugated boxes are easily and highly recyclable. Large producers such as grocery store warehouses and factories have recycled their corrugated boxes for some time. If shredded properly, uncoated corrugated boxes are easily compostable.

  11. Waste product profile: Corrugated boxes

    SciTech Connect

    Miller, C.

    1995-10-01

    As with all packages, corrugated boxes can be lightweighted. Using less linerboard has resulted in a 10% to 15% weight reduction in the last 10 years. However, the need to meet compression`s tacking strength, and burst tests limits the ability to lightweight corrugated boxes. Ironically, heavy use of recycled-content fibers can increase the weight of a corrugated box in order to meet the requirements of these tests. Corrugated boxes can be reused before recycling. Corrugated boxes are easily and highly recyclable. Large producers, such as grocery store warehouses and factories, have recycled their corrugated boxes for some time. These outlets produced sufficient amounts of OCC to justify the cost of baling equipment. If shredded properly, corrugated boxes are easily compostable. Corrugated boxes have a per-pound heating value of 7,047 Btus (compared with 4,500 for a pound of MSW). Like most materials, corrugated boxes degrade slowly in a modern landfill.

  12. 7. View north at back (canal side) of culvert inlet, ...

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

    7. View north at back (canal side) of culvert inlet, with canal bank completely removed. Background to foreground: back of inlet headwall with tops of high inlet barrels exposed; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall at site of former canal edge of canal bank; dewatered canal bed and plank sheathing on top of culvert barrels beneath canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  13. 8. VIEW OF DOWNSTREAM OUTLET CULVERT AND WING RETAINING WALLS, ...

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

    8. VIEW OF DOWNSTREAM OUTLET CULVERT AND WING RETAINING WALLS, LOOKING NORTHWEST - High Mountain Dams in Upalco Unit, Twin Pots Dam, Ashley National Forest, 10.1 miles North of Mountain Home, Mountain Home, Duchesne County, UT

  14. 11. VIEW OF FLOOD GATE FOR THE PRESSURE CULVERT AND ...

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

    11. VIEW OF FLOOD GATE FOR THE PRESSURE CULVERT AND THE SOUTH AND EAST ELEVATIONS, LOOKING NORTHWEST. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

  15. 8. Double arch culvert on Laurel Creek Road looking WSW. ...

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

    8. Double arch culvert on Laurel Creek Road looking WSW. - Great Smoky Mountains National Park Roads & Bridges, Cades Cove Road & Laurel Creek Road, From Townsend Wye to Cades Cove, Gatlinburg, Sevier County, TN

  16. 9. Double arch culvert on Laurel Creek Road looking ENE. ...

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

    9. Double arch culvert on Laurel Creek Road looking ENE. - Great Smoky Mountains National Park Roads & Bridges, Cades Cove Road & Laurel Creek Road, From Townsend Wye to Cades Cove, Gatlinburg, Sevier County, TN

  17. Contextual view showing drainage culvert in foreground boarding east side ...

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

    Contextual view showing drainage culvert in foreground boarding east side of knoll with eucalyptus windbreak. Camera facing 278" southwest. - Goerlitz House, 9893 Highland Avenue, Rancho Cucamonga, San Bernardino County, CA

  18. 7. EAST PORTAL OF CONCRETE LINED CULVERT LOCATED 30 YARDS ...

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

    7. EAST PORTAL OF CONCRETE LINED CULVERT LOCATED 30 YARDS WEST OF HAPPY ISLES BRIDGE. NOTE ROCK & CONCRETE FLOOR. - Happy Isles Bridge, Spanning Merced River on Service road, Yosemite Village, Mariposa County, CA

  19. 6. View southwest, culvert inlet with canal bank completely removed. ...

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

    6. View southwest, culvert inlet with canal bank completely removed. Left to right: back of headwall; tops of high inlet barrels; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall along former edge of canal bank; dewatered canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  20. Dealing with uncertainty when assessing fish passage through culvert road crossings

    USGS Publications Warehouse

    Anderson, Gregory B.; Freeman, Mary C.; Freeman, Byron J.; Straight, Carrie A.; Hagler, Megan M.; Peterson, James T.

    2012-01-01

    Assessing the passage of aquatic organisms through culvert road crossings has become increasingly common in efforts to restore stream habitat. Several federal and state agencies and local stakeholders have adopted assessment approaches based on literature-derived criteria for culvert impassability. However, criteria differ and are typically specific to larger-bodied fishes. In an analysis to prioritize culverts for remediation to benefit imperiled, small-bodied fishes in the Upper Coosa River system in the southeastern United States, we assessed the sensitivity of prioritization to the use of differing but plausible criteria for culvert impassability. Using measurements at 256 road crossings, we assessed culvert impassability using four alternative criteria sets represented in Bayesian belief networks. Two criteria sets scored culverts as either passable or impassable based on alternative thresholds of culvert characteristics (outlet elevation, baseflow water velocity). Two additional criteria sets incorporated uncertainty concerning ability of small-bodied fishes to pass through culverts and estimated a probability of culvert impassability. To prioritize culverts for remediation, we combined estimated culvert impassability with culvert position in the stream network relative to other barriers to compute prospective gain in connected stream habitat for the target fish species. Although four culverts ranked highly for remediation regardless of which criteria were used to assess impassability, other culverts differed widely in priority depending on criteria. Our results emphasize the value of explicitly incorporating uncertainty into criteria underlying remediation decisions. Comparing outcomes among alternative, plausible criteria may also help to identify research most needed to narrow management uncertainty.

  1. Corrugation crack front waves

    E-print Network

    J. R. Willis; N. V. Movchan; A. B. Movchan

    2012-06-05

    The paper presents a model of a dynamic crack with a wavy surface. So far, theoretical analysis of crack front waves has been performed only for in-plane perturbations of the crack front. In the present paper, generalisation is given to a more general three-dimensional perturbation, and equations that govern corrugation crack front waves are derived and analysed.

  2. Remaining Sites Verification Package for the 100-F-50 Stormwater Runoff Culvert, Waste Site Reclassification Form 2007-001

    SciTech Connect

    J. M. Capron

    2008-04-15

    The 100-F-50 waste site, part of the 100-FR-2 Operable Unit, is a steel stormwater runoff culvert that runs between two railroad grades in the south-central portion of the 100-F Area. The culvert exiting the west side of the railroad grade is mostly encased in concrete and surrounded by a concrete stormwater collection depression partially filled with soil and vegetation. The drain pipe exiting the east side of the railroad grade embankment is partially filled with soil and rocks. The 100-F-50 stormwater diversion culvert confirmatory sampling results support a reclassification of this site to no action. The current site conditions achieve the remedial action objectives and corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  3. An Improved Method of Manufacturing Corrugated Boxes: Lateral Corrugator

    SciTech Connect

    Frank C. Murray Ph.D.; , Roman Popil Ph.D.; Michael Shaepe

    2008-12-18

    Paper physicists have known that a corrugated box constructed from outer liner sheets having a predominant fiber orientation aligned with the corrugating flute direction would have higher stiffness and crush resistance (per unit of fiber weight) than the conventional box construction. Such increased performance per unit of fiber weight could result in fiber reduction and energy savings for boxes having equivalent performance specifications. The goal of this project was to develop and demonstrate a commercially viable lateral corrugating process. This included designing and building a pilot lateral corrugator, testing and evaluating pilot machine made boxes, and developing a strategy for commercialization.

  4. Culvert Design for Flood Routing considering Sediment Transport W.J. Rahmeyer PhD.1

    E-print Network

    Rahmeyer, William J.

    Culvert Design for Flood Routing considering Sediment Transport W.J. Rahmeyer PhD.1 and W Education Utah State University Brigham City, UT 84302 UNITED STATES OF AMERICA Abstract: Current flood systems where flood flows deliver sediments to and through culvert inlets. Keywords: Culvert bed

  5. Linear Corrugating - Final Technical Report

    SciTech Connect

    Lloyd Chapman

    2000-05-23

    Linear Corrugating is a process for the manufacture of corrugated containers in which the flutes of the corrugated medium are oriented in the Machine Direction (MD) of the several layers of paper used. Conversely, in the conventional corrugating process the flutes are oriented at right angles to the MD in the Cross Machine Direction (CD). Paper is stronger in MD than in CD. Therefore, boxes made using the Linear Corrugating process are significantly stronger-in the prime strength criteria, Box Compression Test (BCT) than boxes made conventionally. This means that using Linear Corrugating boxes can be manufactured to BCT equaling conventional boxes but containing 30% less fiber. The corrugated container industry is a large part of the U.S. economy, producing over 40 million tons annually. For such a large industry, the potential savings of Linear Corrugating are enormous. The grant for this project covered three phases in the development of the Linear Corrugating process: (1) Production and evaluation of corrugated boxes on commercial equipment to verify that boxes so manufactured would have enhanced BCT as proposed in the application; (2) Production and evaluation of corrugated boxes made on laboratory equipment using combined board from (1) above but having dual manufactures joints (glue joints). This box manufacturing method (Dual Joint) is proposed to overcome box perimeter limitations of the Linear Corrugating process; (3) Design, Construction, Operation and Evaluation of an engineering prototype machine to form flutes in corrugating medium in the MD of the paper. This operation is the central requirement of the Linear Corrugating process. Items I and II were successfully completed, showing predicted BCT increases from the Linear Corrugated boxes and significant strength improvement in the Dual Joint boxes. The Former was constructed and operated successfully using kraft linerboard as the forming medium. It was found that tensile strength and stretch characteristics of the corrugating medium were not sufficient to allow fluting this paper in the former. Possible causes and corrective actions to overcome this problem are addressed in the body of the report below.

  6. 7. VIEW OF WEAPONS DELIVERY ROAD CULVERT OF LOWER DIAGONAL ...

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

    7. VIEW OF WEAPONS DELIVERY ROAD CULVERT OF LOWER DIAGONAL NO. 1 DRAIN, LOOKING 522 EAST OF NORTH. - Truckee-Carson Irrigation District, Lower Diagonal No. 1 Drain, Bounded by West Gate Road & Weapons Delivery Road, Naval Air Station Fallon, Fallon, Churchill County, NV

  7. 35. Photo of concrete arch culvert constructed by Puget Sound ...

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

    35. Photo of concrete arch culvert constructed by Puget Sound Construction Company, 1911, for the Northern Pacific Railroad, over flume. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  8. 6. VIEW OF WEST GATE ROAD CULVERT OF LOWER DIAGONAL ...

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

    6. VIEW OF WEST GATE ROAD CULVERT OF LOWER DIAGONAL NO. 1 DRAIN, LOOKING 2502 EAST OF NORTH. - Truckee-Carson Irrigation District, Lower Diagonal No. 1 Drain, Bounded by West Gate Road & Weapons Delivery Road, Naval Air Station Fallon, Fallon, Churchill County, NV

  9. 5. VIEW OF WEST GATE ROAD CULVERT OF LOWER DIAGONAL ...

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

    5. VIEW OF WEST GATE ROAD CULVERT OF LOWER DIAGONAL NO. 1 DRAIN, LOOKING 323' EAST OF NORTH. - Truckee-Carson Irrigation District, Lower Diagonal No. 1 Drain, Bounded by West Gate Road & Weapons Delivery Road, Naval Air Station Fallon, Fallon, Churchill County, NV

  10. Flood magnitude and frequency of Main Ditch at the culvert on New Jersey Route 44 and at the Conrail culvert downstream, West Deptford Township, Gloucester County, New Jersey

    USGS Publications Warehouse

    Barringer, Thomas

    1996-01-01

    The magnitude and frequency of floods at Main Ditch at the culvert on New Jersey Route 44 at milepost 8.3 and at the Conrail culvert 0.21 miles downstream, in West Deptford Township, New Jersey, were determined by using the New Jersey Department of Environmental Protection Special Report 38 method. Flood-magnitude and -frequency estimates, as well as drainage-basin characteristics, are included in this report. The 100-year-flood estimates are 285 cubic feet per second at the culvert on New Jersey Route 44 and 345 cubic feet per second at the Conrail culvert.

  11. Shape optimization of corrugated airfoils

    NASA Astrophysics Data System (ADS)

    Jain, Sambhav; Bhatt, Varun Dhananjay; Mittal, Sanjay

    2015-10-01

    The effect of corrugations on the aerodynamic performance of a Mueller C4 airfoil, placed at a 5° angle of attack and Re=10{,}000 , is investigated. A stabilized finite element method is employed to solve the incompressible flow equations in two dimensions. A novel parameterization scheme is proposed that enables representation of corrugations on the surface of the airfoil, and their spontaneous appearance in the shape optimization loop, if indeed they improve aerodynamic performance. Computations are carried out for different location and number of corrugations, while holding their height fixed. The first corrugation causes an increase in lift and drag. Each of the later corrugations leads to a reduction in drag. Shape optimization of the Mueller C4 airfoil is carried out using various objective functions and optimization strategies, based on controlling airfoil thickness and camber. One of the optimal shapes leads to 50 % increase in lift coefficient and 23 % increase in aerodynamic efficiency compared to the Mueller C4 airfoil.

  12. Stacked Corrugated Horn Rings

    NASA Technical Reports Server (NTRS)

    Sosnowski, John B.

    2010-01-01

    This Brief describes a method of machining and assembly when the depth of corrugations far exceeds the width and conventional machining is not practical. The horn is divided into easily machined, individual rings with shoulders to control the depth. In this specific instance, each of the corrugations is identical in profile, and only differs in diameter and outer profile. The horn is segmented into rings that are cut with an interference fit (zero clearance with all machining errors biased toward contact). The interference faces can be cut with a reverse taper to increase the holding strength of the joint. The taper is a compromise between the interference fit and the clearance of the two faces during assembly. Each internal ring is dipped in liquid nitrogen, then nested in the previous, larger ring. The ring is rotated in the nest until the temperature of the two parts equalizes and the pieces lock together. The resulting assay is stable, strong, and has an internal finish that cannot be achieved through other methods.

  13. Culvert Analysis Program Graphical User Interface 1.0--A preprocessing and postprocessing tool for estimating flow through culvert

    USGS Publications Warehouse

    Bradley, D. Nathan

    2013-01-01

    The peak discharge of a flood can be estimated from the elevation of high-water marks near the inlet and outlet of a culvert after the flood has occurred. This type of discharge estimate is called an “indirect measurement” because it relies on evidence left behind by the flood, such as high-water marks on trees or buildings. When combined with the cross-sectional geometry of the channel upstream from the culvert and the culvert size, shape, roughness, and orientation, the high-water marks define a water-surface profile that can be used to estimate the peak discharge by using the methods described by Bodhaine (1968). This type of measurement is in contrast to a “direct” measurement of discharge made during the flood where cross-sectional area is measured and a current meter or acoustic equipment is used to measure the water velocity. When a direct discharge measurement cannot be made at a streamgage during high flows because of logistics or safety reasons, an indirect measurement of a peak discharge is useful for defining the high-flow section of the stage-discharge relation (rating curve) at the streamgage, resulting in more accurate computation of high flows. The Culvert Analysis Program (CAP) (Fulford, 1998) is a command-line program written in Fortran for computing peak discharges and culvert rating surfaces or curves. CAP reads input data from a formatted text file and prints results to another formatted text file. Preparing and correctly formatting the input file may be time-consuming and prone to errors. This document describes the CAP graphical user interface (GUI)—a modern, cross-platform, menu-driven application that prepares the CAP input file, executes the program, and helps the user interpret the output

  14. Turtles and culverts, and alternative energy development: an unreported but potentially significant mortality threat to the desert tortoise (Gopherus agassizii)

    USGS Publications Warehouse

    Lovich, J.E.; Ennen, J.R.; Madrak, S.; Grover, B.

    2011-01-01

    Culverts are often used to increase the permeability of roaded landscapes for wildlife, including turtles. Although the benefits of culverts as safe passages for turtles are well documented, under some conditions culverts can entrap them and cause mortality. Here we report a culvert-related mortality in the federally threatened desert tortoise (Gopherus agassizii) at a wind energy facility in California and offer simple recommendations to mitigate the negative effects of culverts for wildlife in general.

  15. 24. CULVERT WITH CONCRETE HEADWALL AND SIDEWALLS CARRYING THE LATERAL ...

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

    24. CULVERT WITH CONCRETE HEADWALL AND SIDEWALLS CARRYING THE LATERAL UNDER 8TH AVENUE. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

  16. A Simple Experiment to Explore Standing Waves in a Flexible Corrugated Sound Tube

    ERIC Educational Resources Information Center

    Amorim, Maria Eva; Sousa, Teresa Delmira; Carvalho, P. Simeao; Sousa, Adriano Sampaioe

    2011-01-01

    Sound tubes, pipes, and singing rods are used as musical instruments and as toys to perform amusing experiments. In particular, corrugated tubes present unique characteristics with respect to the sounds they can produce; that is why they have been studied so intensively, both at theoretical and experimental levels. Experimental studies usually…

  17. Multistable and morphing corrugated shell structures

    E-print Network

    Norman, Alexander David

    2009-06-09

    algebraic model describes their behaviour, as does a numerical model. These models consider the strong coupling that occurs between bending and stretching in corrugated shells; and (iii) 'doubly-corrugated ' sheets, similar to an eggbox in concept, which...

  18. C&O Canal Fifteen Mile Creek Culvert in foreground, south portal ...

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

    C&O Canal Fifteen Mile Creek Culvert in foreground, south portal of Western Maryland's Fifteen Mile Creek Culvert in rear, looking west. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  19. Exact sampling of corrugated surfaces

    E-print Network

    Sergio Caracciolo; Enrico Rinaldi; Andrea Sportiello

    2008-10-15

    We discuss an algorithm for the exact sampling of vectors v in [0,1]^N satisfying a set of pairwise difference inequalities. Applications include the exact sampling of skew Young Tableaux, of configurations in the Bead Model, and of corrugated surfaces on a graph, that is random landscapes in which at each vertex corresponds a local maximum or minimum. As an example, we numerically evaluate with high-precision the number of corrugated surfaces on the square lattice. After an extrapolation to the thermodynamic limit, controlled by an exact formula, we put into evidence a discrepancy with previous numerical results.

  20. MONITORING CULVERT PASSAGE OF JUVENILE SALMONIDS WITH PIT TAGS AND STATIONARY AND PORTABLE PIT-TAG READERS

    EPA Science Inventory

    Federal land management agencies in the PNW face increasing pressure to replace culverts that do not pass all life history stages of anadromous salmon and trout. Prioritization of culverts for replacement is often based on the physical parameters of culverts, and not on how fish...

  1. Corrugated Membrane Fuel Cell Structures

    SciTech Connect

    Grot, Stephen President, Ion Power Inc.

    2013-09-30

    One of the most challenging aspects of traditional PEM fuel cell stacks is the difficulty achieving the platinum catalyst utilization target of 0.2 gPt/kWe set forth by the DOE. Good catalyst utilization can be achieved with state-of-the-art catalyst coated membranes (CCM) when low catalyst loadings (<0.3 mg/cm2) are used at a low current. However, when low platinum loadings are used, the peak power density is lower than conventional loadings, requiring a larger total active area and a larger bipolar plate. This results in a lower overall stack power density not meeting the DOE target. By corrugating the fuel cell membrane electrode structure, Ion Power?s goal is to realize both the Pt utilization targets as well as the power density targets of the DOE. This will be achieved by demonstrating a fuel cell single cell (50 cm2) with a twofold increase in the membrane active area over the geometric area of the cell by corrugating the MEA structure. The corrugating structure must be able to demonstrate the target properties of < 10 mOhm-cm2 electrical resistance at > 20 psi compressive strength over the active area, in combination with offering at least 80% of power density that can be achieved by using the same MEA in a flat plate structure. Corrugated membrane fuel cell structures also have the potential to meet DOE power density targets by essentially packaging more membrane area into the same fuel cell volume as compared to conventional stack constructions.

  2. A Simple Experiment to Explore Standing Waves in a Flexible Corrugated Sound Tube

    NASA Astrophysics Data System (ADS)

    Amorim, Maria Eva; Sousa, Teresa Delmira; Carvalho, P. Simeão; Sousa, Adriano Sampaioe

    2011-09-01

    Sound tubes, pipes, and singing rods are used as musical instruments and as toys to perform amusing experiments. In particular, corrugated tubes present unique characteristics with respect to the sounds they can produce; that is why they have been studied so intensively, both at theoretical and experimental levels.1-4 Experimental studies usually involve expensive and sophisticated equipment that is out of reach of school laboratory facilities.3-6 In this paper we show how to investigate quantitatively the sounds produced by a flexible sound tube corrugated on the inside by using educational equipment readily available in school laboratories, such as the oscilloscope, the microphone, the anemometer, and the air pump. We show that it is possible for students to study the discontinuous spectrum of sounds produced by a flexible corrugated tube and go even further, computing the speed of sound in air with a simple experimental procedure.

  3. A parametric study of cut-off corrugated surface properties

    NASA Technical Reports Server (NTRS)

    Mentzer, C. A.; Peters, L., Jr.

    1973-01-01

    Corrugated horns involve a junction between the corrugated surface and a conducting groundplane. Proper horn design requires an understanding of the electromagnetic properties of the corrugated surface and this junction. Therefore, an integral equation solution has been used to study the influence of corrugation density and shape on the power loss. Surface current, and the scattering from a groundplane-corrugated surface junction. Both square and vee shape corrugations have been considered over the range of corrugation depths where the surface acts as a cut-off corrugated surface.

  4. Flood magnitude and frequency of Little Mantual Creek at the culvert at milepost 7.8 on New Jersey Route 44, and at the Conrail culvert 0.20 miles downstream, West Deptford Township, Gloucester County, New Jersey

    USGS Publications Warehouse

    Barringer, Thomas

    1996-01-01

    The magnitude and frequency of floods at Little Mantua Creek at the culvert on New Jersey Route 44 at milepost 7.8 and at the Conrail culvert 0.20 miles downstream, in West Deptford Township, New Jersey, were determined by using the New Jersey Department of Environmental Protection Special Report 38 method. Flood-magnitude and -frequency estimates, as well as drainage-basin characteristics, are included in this report. The 100-year-flood estimates are 249 cubic feet per second at the culvert on New Jersey Route 44, and 243 cubic feet per second at the Conrail culvert.

  5. Bioinspired Corrugated Airfoil at Low Reynolds Numbers

    E-print Network

    Hu, Hui

    -speed wind tunnel. A high-resolution particle image velocimetry system was used to conduct detailed flowfield airfoils. The particle image velocimetry measurement results demonstrated clearly that the corrugated in the valleys of the corrugated cross section would pump high-speed fluid from outside to near-wall regions

  6. Mechanical Analysis of Trapezoidal Corrugated Composite Skins

    NASA Astrophysics Data System (ADS)

    Ghabezi, P.; Golzar, M.

    2013-08-01

    Using of the corrugated skins and morphing technology is a good idea to provide the desired performance and improve aerodynamic efficiency. Corrugated structures and skins are flexible in the direction of corrugation and stiff in the transverse direction. In this paper a simple analytical model for the effective stiffness of the trapezoidal corrugated composites is developed in symmetrical and unsymmetrical lay-up. The elongation and effective stiffness in longitudinal and transverse directions of trapezoidal corrugated skins and flat composites are extracted using strain energy and Castiglione's theorem. Various dimensions of trapezoidal element for unidirectional and plain woven fabrics of E-glass/Epoxy are investigated. Trapezoidal corrugated composites were modelled by commercial FEM software ABAQUS and compared to analytical model. Analytical model is validated by experimental results from bending and tensile tests. Finally, load-displacement curves in the tensile and bending tests are studied and their different stages of behavior are identified. Results of FEM, experimental and analytical simulation show that how the corrugated composite skins can afford obviously larger deformation than the flat one and they are good solution to use in the morphing applications.

  7. CORRECTING UNRELIABLE VELOCITY DISTRIBUTIONS IN SHORT CULVERTS AND CANAL REACHES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation water management increasingly depends on good water flow measurement. Too frequently, flow disturbances from upstream elbows, the well pump, or other pipe fittings, produce distorted flow profiles that are detrimental to the proper installation and operation of common flow meters used in...

  8. Surface-Water Exchange through Culverts beneath State Road 9336 within Everglades National Park, 2004-05

    USGS Publications Warehouse

    Schaffranek, Raymond W.; Stewart, Marc A.; Nowacki, Daniel J.

    2008-01-01

    The U.S. Geological Survey collected hydrologic data between June 2004 and December 2005 to investigate the temporal and spatial nature of flow exchanges through culverts beneath State Road 9336 within Everglades National Park. Continuous data collected during the study measured flow velocity, water level, salinity, conductivity, and water-temperature in or near seven culverts between Pa-hay-okee Overlook access road and Nine Mile Pond. The two culverts east of Pa-hay-okee Overlook access road flowed into Taylor Slough Basin from 87 to 96 percent of the study period, whereas flows through five culverts between Pa-hay-okee Overlook access road and Nine Mile Pond flowed into Shark River Slough Basin from 70 to 99 percent of the study period. Synoptic flow discharges measured at all culverts during three intensive field efforts revealed a net discharge into Taylor Slough Basin from Shark River Slough Basin through culverts between Royal Palm Road and Pa-hay-okee Overlook access road, and into Shark River Slough Basin from Taylor Slough Basin through culverts between Pa-hay-okee Overlook access road and Nine Mile Pond. Data collected during the study and presented in this report provided additional knowledge of the magnitude, direction, and nature of flow exchanges through the road culverts.

  9. Method and apparatus for corrugating strips

    DOEpatents

    Day, Jack R. (Oak Ridge, TN); Curtis, Charles H. (Kingston, TN)

    1983-01-01

    The invention relates to a method and a machine for transversely corrugating a continuous strip of metallic foil. The product foil comprises a succession of alternately disposed corrugations, each defining in cross section, a major segment of a circle. The foil to be corrugated is positioned to extend within a vertical passage in the machine. The walls of the passage are heated to promote the desired deformation of the foil. Foil-deforming rollers are alternately passed obliquely across the passage to respectively engage transverse sections of the foil. The rollers and their respective section of deformed foil comprise a stacked assembly which is moved incrementally through the heated passageway. As the assembly emerges from the passageway, the rollers spill from the corrugated foil and are recovered for re-use.

  10. Evolutionary design of corrugated horn antennas

    NASA Technical Reports Server (NTRS)

    Hoorfar, F.; Manshadi, V.; Jamnejad, A.

    2002-01-01

    An evolutionary progranirnitzg (EP) algorithm is used to optimize pattern of a corrugated circularhorn subject to various constraints on return loss and antenna beamwidth and pattern circularity and low crosspolarization. The EP algorithm uses a Gaussian mutation operator. Examples on design synthesis of a 45 section corrugated horn, with a total of 90 optimization parameters, are presented. The results show excellent and efficient optimization of the desired horn parameters.

  11. Imaging Buried Culverts Using Ground Penetrating Radar: Comparing 100 MHZ Through 1 GHZ Antennae

    NASA Astrophysics Data System (ADS)

    Abdul Aziz, A.; Stewart, R. R.; Green, S. L.

    2013-12-01

    *Aziz, A A aabdulaziz@uh.edu Allied Geophysical Lab, Department of Earth and Atmospheric Sciences, University of Houston, TX, USA Stewart, R R rrstewart@uh.edu Allied Geophysical Lab, Department of Earth and Atmospheric Sciences, University of Houston, TX, USA *Green, S L slgreen@yahoo.com Allied Geophysical Lab, Department of Earth and Atmospheric Sciences, University of Houston, TX, USA A 3D ground penetrating radar (GPR) survey, using three different frequency antennae, was undertaken to image buried steel culverts at the University of Houston's La Marque Geophysical Observatory 30 miles south of Houston, Texas. The four culverts, under study, support a road crossing one of the area's bayous. A 32 m by 4.5 m survey grid was designed on the road above the culverts and data were collected with 100 MHz, 250 MHz, and 1 GHz antennae. We used an orthogonal acquisition geometry for the three surveys. Inline sampling was from 1.0 cm to 10 cm (from 1 GHz to 100 MHz antenna) with inline and crossline spacings ranging from 0.2 m to 0.5 m. We used an initial velocity of 0.1 m/ns (from previous CMP work at the site) for the display purposes. The main objective of the study was to analyze the effect of different frequency antennae on the resultant GPR images. We are also interested in the accuracy and resolution of the various images, in addition to developing an optimal processing flow.The data were initially processed with standard steps that included gain enhancement, dewow and temporal-filtering, background suppression, and 2D migration. Various radar velocities were used in the 2D migration and ultimately 0.12 m/ns was used. The data are complicated by multipathing from the surface and between culverts (from modeling). Some of this is ameliorated via deconvolution. The top of each of the four culverts was evident in the GPR images acquired with the 250 MHz and 100 MHz antennas. For 1 GHz, the top of the culvert was not clear due to the signal's attenuation. The 250 MHz shielded antenna provides a vertical resolution of about 0.1 m and is the choice to image the culverts. The 100 MHz antenna provided an increment in depth of penetration, but at the expense of a substantially diminished resolution (0.25 m).

  12. An Analysis of Stream Culvert Fish Passage on the Navy Railroad Line between Bremerton and Shelton, Washington

    SciTech Connect

    May, Christopher W.; Miller, Martin C.; Southard, John A.

    2004-10-25

    The Navy railroad service line runs between Shelton, Bremerton, and Silverdale, and is used by the Navy to transfer freight to its facilities. It is also used by commercial clients to ship service items and bulk cargo for municipalities along portions of the route. Culverts of various size and construction convey streams and stormwater runoff under the railroad line. These allow transfer of water and, in some cases allow for passage of juvenile and adult salmon into waters upstream of the culverts. As part of this project, 21 culverts along a 34-mile reach (Shelton to Bremerton) of this railroad were surveyed to evaluate their function and ability to allow salmon to utilize the streams. The culverts and attached watersheds were evaluated using criteria developed by the Washington Department of Fish and Wildlife to assign a Priority Index (PI) to barriers present on each fish-bearing stream. The PI is a relative numeric rating indicator, assigned using consistent criteria related to the degree of potential habitat gained by removing barriers and improving the function of the watershed. Of the 21 culverts evaluated, five were found to be complete fish-passage barriers and six were found to be partial barriers, primarily to juvenile salmon. Three of these culverts had PI ratings above 10 and five others had ratings between 7 and 10. Corrective action can be taken based on any PI rating, but the WDFW normally assigns lower priority to projects with PI scores lower than 15. Several of the stream and culverts had previously been evaluated for structural integrity and function and have been scheduled for repair. A narrative indicating the condition of the culvert has been prepared as well as a table indicating the PI scores and a summary of recommendations for action for each culvert.

  13. High frequency scattering from corrugated stratified cylinders

    NASA Technical Reports Server (NTRS)

    Sarabandi, Kamal; Ulaby, Fawwaz T.

    1991-01-01

    Interest in applying radar remote sensing for the study of forested areas led to the development of a model for scattering from corrugated stratified dielectric cylinders. The model is used to investigate the effect of bark and its roughness on scattering from tree trunks and branches. The outer layer of the cylinder (bark) is assumed to be a low-loss dielectric material and to have a regular (periodic) corrugation pattern. The inner layers are treated as lossy dielectrics with smooth boundaries. A hybrid solution based on the moment method and the physical optics approximation is obtained. In the solution, the corrugations are replaced with polarization currents that are identical to those of the local tangential periodic corrugated surface, and the stratified cylinder is replaced with equivalent surface currents. New expressions for the equivalent physical-optics currents are used which are more convenient than the standard ones. It is shown that the bark layer and its roughness both reduce the radar cross-section. It is also demonstrated that the corrugations can be replaced by an equivalent anisotropic layer.

  14. Linearly Polarized Modes of a Corrugated Metallic Waveguide

    E-print Network

    Kowalski, Elizabeth Joan

    A linearly polarized (LP[subscript mn]) mode basis set for oversized, corrugated, metallic waveguides is derived for the special case of quarter-wavelength-depth circumferential corrugations. The relationship between the ...

  15. Disappointment and regret enhance corrugator reactivity in a gambling task

    E-print Network

    Wu, Yin; Clark, Luke

    2014-01-01

    This study investigated how the corrugator and zygomaticus respond to decision outcomes, i.e. gains and losses. We used a gambling task in which participants were presented with obtained followed by non-obtained outcomes. Activity at the corrugator...

  16. Ultrasonic geometrical characterization of periodically corrugated surfaces.

    PubMed

    Liu, Jingfei; Declercq, Nico F

    2013-04-01

    Accurate characterization of the characteristic dimensions of a periodically corrugated surface using ultrasonic imaging technique is investigated both theoretically and experimentally. The possibility of accurately characterizing the characteristic dimensions is discussed. The condition for accurate characterization and the quantitative relationship between the accuracy and its determining parameters are given. The strategies to avoid diffraction effects instigated by the periodical nature of a corrugated surface are also discussed. Major causes of erroneous measurements are theoretically discussed and experimentally illustrated. A comparison is made between the presented results and the optical measurements, revealing acceptable agreement. This work realistically exposes the capability of the proposed ultrasonic technique to accurately characterize the lateral and vertical characteristic dimensions of corrugated surfaces. Both the general principles developed theoretically as well as the proposed practical techniques may serve as useful guidelines to peers. PMID:23294990

  17. Buckling Analysis of Axially Loaded Corrugated Cylindrical Shells

    E-print Network

    Pellegrino, Sergio

    Buckling Analysis of Axially Loaded Corrugated Cylindrical Shells Xin Ning and Sergio Pellegrino California Institute of Technology, Pasadena, CA 91125 Buckling analyses of heavily corrugated cylindrical for corrugated cylindrical shells which builds on the Bloch wave method for infinitely periodic structures. We

  18. Study of five corrugated case designs 

    E-print Network

    Rogers, Roxanne Russell

    1996-01-01

    The purpose of the research described in this thesis is to define the primary damages occurring to corrugated cases in the normal distribution system of Frito-Lay, Incorporated and compare the relative performance (to be defined in terms of trip...

  19. Operating experience firing waxed corrugated cardboard waste

    SciTech Connect

    McBurney, B.

    1995-09-01

    Georgia-Pacific operates a corrugated packaging facility in Doraville, Georgia which a suburb of Atlanta. The plant processes bulk brown paper into corrugated sheets for corrugated packaging. The plant`s process and building heat requires approximately 15,000 PPH steam at 150 psig which was supplied by a natural gas fired package boiler. The mill disposed of the cardboard trimmings and waste in a nearby landfill at a disposal cost of several thousand dollars per month. In 1992, the mill recognized that the landfill would close in several years which would result in a significant increase in monthly cardboard waste disposal costs. Therefore, the mill sought an alternate yet economical solution for waste disposal. After evaluating several different alternatives including recycling, the mill installed a boiler system designed to fire the waxed corrugated cardboard waste (WCW) as both a solution for disposal of this waste and as an alternate source of boiler fuel. This paper reviews plant design, operating performance and maintenance history.

  20. 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.

  1. Thermal Insulation Test of new Designed Cryogenic Pipes for the Superconducting DC Power Transmission System in Ishikari, Japan

    NASA Astrophysics Data System (ADS)

    Watanabe, Hirofumi; Ivanov, Yury V.; Hamabe, Makoto; Chikumoto, Noriko; Takano, Hirohisa; Yamaguchi, Satarou

    New cryogenic pipes were designed for the superconducting DC power transmission systems constructed in the Ishikari area in Japan. In the designs two inner pipes, for the cable and for the return of liquid nitrogen, are installed in a single outer pipe for the circulation of liquid nitrogen. In contrast to the cryogenic pipes commonly used for the superconducting power transmission, in which corrugated pipes are used, straight pipes are adopted to reduce pressure loss of the circulation of the liquid nitrogen. A radiation shield to reduce heat leak to the inner pipe for the cable is adopted in one of the designs. Two types of test pipes with and without the radiation shield were constructed and heat leak of these pipes was measured to evaluate the effciency of the test pipes. The lowest heat leak of 0.73 W/m was measured for the test pipe with the radiation shield.

  2. A 2-GHz Rectangular Corrugated Horn

    SciTech Connect

    Bersanelli, M.; Bensadoun, M.; De Amici, Giovanni; Limon, M.; Smoot, George F.; Tanaka, S.; Witebsky, C.; Yamada, J.

    1991-10-01

    We have designed, constructed and tested a large, rectangular horn antenna with a center frequency of 2.0 GHz, corrugated on the E-plane walls, made out of aluminum sheet. A new technique has been developed to solder thin aluminum strips onto the back plane to form the corrugations. The radiation beam pattern shows half-power beamwidths of 12{sup 0} and 14{sup 0} in the H and E planes respectively, and side lobe response below -40 dB at angles greater than 50{sup 0} from horn axis. The measured return loss is less than -20 dB (VSWR < 1.22) between 1.7 and 2.3 GHz; insertion loss is less than 0.15 dB.

  3. Pipe Dreams.

    ERIC Educational Resources Information Center

    Milshtein, Amy

    2002-01-01

    Discusses the importance of attention to plumbing in college facilities, offering examples from various campuses. Addresses preventive maintenance, technology, and piping materials, including the debate between cast iron and PVC for drain pipes. (EV)

  4. Heat Pipes

    ERIC Educational Resources Information Center

    Lewis, J.

    1975-01-01

    Describes the construction, function, and applications of heat pipes. Suggests using the heat pipe to teach principles related to heat transfer and gives sources for obtaining instructional kits for this purpose. (GS)

  5. Performance of zigzag corrugated furrows in Bolivia

    NASA Astrophysics Data System (ADS)

    Roldán Cañas, J.; Chipana, R.; Moreno-Pérez, M. F.; Chipana, G.

    2012-04-01

    In Bolivia, irrigation area is estimated in more than 250000 ha, being surface irrigation the most common method. In highland areas (Altiplano) and in interandean valleys, traditional and ancestral irrigation systems such as flood irrigation, contour furrows, zigzag corrugated furrows, suka kollus and irrigation by kanis, are the most important. In the case of very steep terrains and shallow soils, the zigzag corrugated irrigation method is very frequent. This irrigation method has been used for a long time but their low application efficiency and the shortage of water justify this work devoted to their characterization and to study their performance. The experimental study was conducted southeast of the city of La Paz in the community of Cebollino located at 2600 meters above sea level. Furrow characteristics vary in function of crop type and soil slope, so that the larger the slope the greater the separation between furrows. In our case, the crop chosen was the lettuce and the experimental plot had an area of 800 m2 with a slope ranging between 14 and 18%. Blocks of corrugated furrows were identified and experimental measures were made during each irrigation, once per week, in the central blocks to avoid border effects. To determine advance curves 15 stations were used spaced 18 m. At each station, advance and recession time and infiltration depth were measured. Inlet and outlet flow were controlled each 5 min. To calculate the reference evapotranspiration, the Hargraves-Samani equation was used. Due to the very high terrain slopes, the advance curve takes a linear form rather than the typical exponential form. This hinders the proper calculation of the parameters of the Kostiakov-Lewis equation used to determine the infiltrated depth values. The inlet flow range, along irrigation events, between 0.01 and 0.085 L/s due to the uncontrolled use of water in fields located upstream. The large variability of inflow flow difficult irrigation management especially in regard to the system organization and operation.

  6. Disappointment and regret enhance corrugator reactivity in a gambling task

    PubMed Central

    Wu, Yin; Clark, Luke

    2015-01-01

    This study investigated how the corrugator and zygomaticus respond to decision outcomes (i.e., gains and losses). We used a gambling task in which participants were presented with obtained followed by non-obtained outcomes. Activity at the corrugator site was sensitive to decision outcomes, such that higher obtained losses (disappointment) and higher non-obtained gains (regret) both heightened corrugator reactivity. Activity at the zygomaticus site was not responsive to obtained or non-obtained outcomes, but did show sensitivity to emotional images in the same participants, in the form of a positive linear relationship with self-reported emotional valence. Corrugator activity was negatively related to emotional valence. The findings indicate the sensitivity of corrugator to objective decision outcomes and also counterfactual comparisons, highlighting the utility of facial electromyography in research on decision making and gambling behavior. PMID:25345723

  7. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Phoenix Refrigeration Systems, Inc.'s heat pipe addition to the Phoenix 2000, a supermarket rooftop refrigeration/air conditioning system, resulted from the company's participation in a field test of heat pipes. Originally developed by NASA to control temperatures in space electronic systems, the heat pipe is a simple, effective, heat transfer system. It has been used successfully in candy storage facilities where it has provided significant energy savings. Additional data is expected to fully quantify the impact of the heat pipes on supermarket air conditioning systems.

  8. Biased Brownian motion in extremely corrugated tubes

    NASA Astrophysics Data System (ADS)

    Martens, S.; Schmid, G.; Schimansky-Geier, L.; Hänggi, P.

    2011-12-01

    Biased Brownian motion of point-size particles in a three-dimensional tube with varying cross-section is investigated. In the fashion of our recent work, Martens et al. [Phys. Rev. E 83, 051135 (2011)] we employ an asymptotic analysis to the stationary probability density in a geometric parameter of the tube geometry. We demonstrate that the leading order term is equivalent to the Fick-Jacobs approximation. Expression for the higher order corrections to the probability density is derived. Using this expansion orders, we obtain that in the diffusion dominated regime the average particle current equals the zeroth order Fick-Jacobs result corrected by a factor including the corrugation of the tube geometry. In particular, we demonstrate that this estimate is more accurate for extremely corrugated geometries compared with the common applied method using a spatially-dependent diffusion coefficient D(x, f) which substitutes the constant diffusion coefficient in the common Fick-Jacobs equation. The analytic findings are corroborated with the finite element calculation of a sinusoidal-shaped tube.

  9. Corrugated Quantum Well Infrared Photodetectors and Arrays

    NASA Technical Reports Server (NTRS)

    Choi, K. K.; Chen, C. J.; Rohkinson, L. P.; Das, N. C.; Jhabvala, M.

    1999-01-01

    Quantum well infrared photodetectors (QWIPs) have many advantages in infrared detection, mainly due to the mature Ill-V material technology. The employment of the corrugation structure further advances the technology by providing a simple, yet efficient light-coupling scheme. A C-QWIP enjoys the same flexibility as a detector with intrinsic normal incident absorption. In this paper, we will discuss the utilities of C-QWIPs in different applications, including two-color detection and polarization-sensitive detection. Besides practical applications, C-QWIPs are also useful in detector characterization. They can be used for measuring the absorption coefficient of light propagating parallel to the layers under bias and providing information on the energy resolved photoconductive gain. These two quantities have never been measured before. Based on the corrugation design, we have made several modifications that further improve the detector sensitivity without increasing its complexity. Other than the C-QWIP structure, we also continue searching for other sensitive detector architectures. In a quantum grid infrared photodetector, 3-dimensional electron confinement can be achieved, with which the detector is able to absorb light in all directions. At the same time, the photoconductive gain can also be improved. We further improve the design using a blazed structure. All the experimental results are supported by a rigorous electromagnetic modal transmission-line theory developed especially for these types of structures. Preliminary thermal imaging using C-QWIP FPAs validates the advantages of the present approach.

  10. 49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... RAILROADS 1 Operating Expenses-Way and Structures § 1242.15 Roadway, tunnels and subways, bridges...

  11. Piping Plover

    USGS Multimedia Gallery

    Chicks and eggs of piping plovers. The piping plover is a small migratory shorebird listed as endangered in Canada and the U.S. Great Lakes, and threatened throughout the remainder of its U.S. breeding and winter range. Recent surveys indicate that there are only about 8,000 adults in existence.  Th...

  12. Piping Plover

    USGS Multimedia Gallery

    An adult piping plover. The piping plover is a small migratory shorebird listed as endangered in Canada and the U.S. Great Lakes, and threatened throughout the remainder of its U.S. breeding and winter range. Recent surveys indicate that there are only about 8,000 adults in existence. The USGS is co...

  13. Plasma outflow from a corrugated trap in the kinetic regime

    SciTech Connect

    Skovorodin, D. I.; Beklemishev, A. D.

    2012-03-15

    The problem of stationary plasma outflow from an open corrugated trap in the kinetic regime is considered with allowance for pair collisions in the framework of a kinetic equation with the Landau collision integral. The distribution function is studied in the limit of small-scale corrugation and a large mirror ratio. In considering a single corrugation cell, a correction for the distribution function is calculated analytically. An equation describing variations of the distribution function along the system is derived and used to study the problem of plasma outflow into vacuum.

  14. Thermal Stability of Corrugated Epitaxial Graphene Grown on Re(0001)

    NASA Astrophysics Data System (ADS)

    Miniussi, E.; Pozzo, M.; Baraldi, A.; Vesselli, E.; Zhan, R. R.; Comelli, G.; Mente?, T. O.; Niño, M. A.; Locatelli, A.; Lizzit, S.; Alfè, D.

    2011-05-01

    We report on a novel approach to determine the relationship between the corrugation and the thermal stability of epitaxial graphene grown on a strongly interacting substrate. According to our density functional theory calculations, the C single layer grown on Re(0001) is strongly corrugated, with a buckling of 1.6 Å, yielding a simulated C 1s core level spectrum which is in excellent agreement with the experimental one. We found that corrugation is closely knit with the thermal stability of the C network: C-C bond breaking is favored in the strongly buckled regions of the moiré cell, though it requires the presence of diffusing graphene layer vacancies.

  15. Fatigue testing of corrugated and Teflon hoses

    NASA Technical Reports Server (NTRS)

    Benner, Steve M.; Swanson, Theodore D.; Costello, Frederick A.

    1990-01-01

    Single and two-phase heat transport systems for the thermal control of large space facilities require fluid lines that traverse joints and either rotate or move in some other manner. Flexible hoses are being considered as one means of traversing these joints. To test the resilience of flexible hoses to bending stress, a test assembly was constructed to determine the number of flexing cycles the hoses could withstand before losing their ability to maintain a constant pressure. Corrugated metal hoses and Teflon hoses were tested at different pressures with nitrogen gas. The metal hoses had lives ranging from 30,000 to 100,000 flexing cycles. But, even after 400,000 cycles, the Teflon hoses remained essentially intact, though some leakage in the convoluted Teflon is noted.

  16. Scheduling and Planning Software for Corrugation Process

    NASA Astrophysics Data System (ADS)

    Chantrapornchai, C.; Sathapanawat, T.

    In this paper, we are interested in developing a software for production planning for the corrugation process. We particularly study the scheduling problem of paper roll feeding in the mills. In the real industry, many constraints are post in order to assign paper rolls to the mill roll stand while the factory has several goals to meet such as saving paper cost and balancing worker loads. Such problems are known to be a difficult problem. We develop a heuristic to find the schedule under the goals to minimize waste, to balance the roll switching, and minimize butt rolls. Then, the web-based application is developed to create such a schedule and simulate the schedule results to verify the solutions.

  17. Piping Analysis

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Burns & McDonnell provide architectural and engineering services in planning, design and construction of a wide range of projects all over the world. In design analysis, company regularly uses COSMIC computer programs. In computer testing piping design of a power plant, company uses Pipe Flexibility Analysis Program (MEL-21) to analyze stresses due to weight, temperature, and pressure found in proposed piping systems. Individual flow rates are put into the computer, then computer calculates the pressure drop existing across each component; if needed, design corrections or adjustments can be made and rechecked.

  18. Piping Flexibility

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A NASA computer program aids Hudson Engineering Corporation, Houston, Texas, in the design and construction of huge petrochemical processing plants like the one shown, which is located at Ju'aymah, Saudi Arabia. The pipes handling the flow of chemicals are subject to a variety of stresses, such as weight and variations in pressure and temperature. Hudson Engineering uses a COSMIC piping flexibility analysis computer program to analyze stresses and unsure the necessary strength and flexibility of the pipes. This program helps the company realize substantial savings in reduced engineering time.

  19. The influence of the microtexture, corrugation inclination angle, and perforation of corrugated surfaces on the character of liquid spreading

    NASA Astrophysics Data System (ADS)

    Pavlenko, A. N.; Li, X.; Li, H.; Gao, X.; Volodin, O. A.; Surtaev, A. S.; Serdyukov, V. S.

    2015-08-01

    The spreading of liquid nitrogen film over the surface of single structured packing elements has been experimentally studied. Comparative analysis of experimental data showed the influence of a horizontal microtexture, perforation, and inclination angle of large corrugation ribs on the character of liquid film spreading over the corrugated surface at various values of the film-flow Reynolds number. Experimental data are also presented on the dependence of the relative fraction of liquid retained in a single irrigated channel in corrugated plates of various thicknesses on the extent of irrigation.

  20. Hydrodynamics of Gas-Liquid Counterflow Through Corrugated Parallel Plates

    SciTech Connect

    de Almeida, V.F.

    1999-11-05

    Structured packings utilized in today's distillation packed towers consist of stacked units of many vertically oriented parallel corrugated plates. The V-shaped corrugations are oriented at a fixed angle with respect to the vertical direction, and the corrugation angle in adjacent plates are oriented in reverse direction. Points of contact, at the crests of the corrugations, between adjacent plates, form an unconsolidated porous medium with known topology. Modern structured packings have been gaining acceptance in several separation processes, particularly distillation where gas/vapor and liquid flow countercurrently through the packing. In addition, structured packings have been credited with relatively low pressure drop, high efficiency, low holdup, and higher capacity; the packing also can be made corrosion resistive.

  1. Contribution to the Modelling of the Corrugated Cardboard Behaviour

    E-print Network

    Allaoui, Samir; Benzeggagh, M L

    2011-01-01

    The current paper summarizes studies undertaken on the corrugated cardboard. In these studies, a new approach considering the corrugated cardboard as an orthotropic material is developed. This approach permits after homogenization to simplify the numerical calculations and then use a 2D meshing of the corrugated cardboard, instead of a 3D meshing. This will makes it possible to obtain less heavy and less expensive numerical dimensioning studies. The first stage of the studies was a determination of the behaviours of the sandwich and its constituents, which passes by the definition of experimental protocols. Thereafter, an analytical model was proposed and permits to predict the homogenized behaviour of the corrugated cardboard. Finally a tool of decision-making aid was proposed.

  2. Low Loss Broadband Multimode Circular Corrugated Waveguide Performance

    NASA Astrophysics Data System (ADS)

    Cavallo, A.; Doane, J.; Cutler, R.; Brenner, J.

    1988-11-01

    A 30 meter long circular corrugated waveguide run (i.d.=6.35 cm) with a corrugation period and depth of 250? has been fabricated. It is designed for low loss (<0.01 dB/m) multimode operation over the frequency range of 75-575 GHz. It will be installed on TFTR (Tokamak Fusion Test Reactor) for use in electron cyclotron emission measurements. Results will be compared to those obtained using conventional tall rectangular C-band waveguide.

  3. Sensitivity to horizontal and vertical corrugations defined by binocular disparity.

    PubMed

    Bradshaw, M F; Rogers, B J

    1999-09-01

    Sensitivity to corrugations defined by binocular disparity differs as a function of the modulation frequency. Such functions have proved to be useful descriptive and analytical tools in the study of the mechanisms involved in disparity processing. Indeed, given certain assumptions, these sensitivity functions can be used to predict certain perceptual outcomes. Given their importance, it is surprising that there is no comprehensive data set of disparity sensitivity functions (DSF) for a range of observers over a broad range of spatial frequencies and orientations. Here we report DSFs for six observers over an eight octave range of sinusoidal corrugations in disparity (0.0125-3.2 cpd). Multi-cycle, low frequency surfaces were used to assess the degree to which the fall-off in sensitivity at low corrugation frequencies is attributable to the decreasing number of cycles displayed. The data was found to form a continuous function despite the different number of cycles displayed. We conclude that the fall off in sensitivity is due to the spatial interactions in disparity processing. We also determined DSFs for the same observers to both vertically and horizontally oriented sinusoidal disparity corrugations in order to characterise the extent of the stereoscopic anisotropy. In general, the best thresholds for detecting vertically oriented disparity corrugations were higher (approximately 4 arc sec) than for horizontally oriented corrugations (approximately 2 arc sec). Moreover, the functions were shifted toward the high spatial frequency end of the spectrum. PMID:10664803

  4. Theoretical study of corrugated plates: Shearing of a trapezoidally corrugated plate with trough lines permitted to curve

    NASA Technical Reports Server (NTRS)

    Lin, C.; Libove, C.

    1971-01-01

    A theoretical analysis is presented of the elastic shearing of a trapezoidally corrugated plate with discrete attachments at the ends of the corrugations. Numerical results on effective shear stiffness, stresses, and displacements are presented for selected geometries and end-attachment conditions. It is shown that the frame-like deformation of the cross-sections, which results from the absence of continuous end attachments, can lead to large transverse bending stresses and large reductions in shearing stiffness.

  5. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than $57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was $28,706, and that figures out to a cost reduction.

  6. Piping Connector

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A complex of high pressure piping at Stennis Space Center carries rocket propellants and other fluids/gases through the Center's Component Test Facility. Conventional clamped connectors tend to leak when propellant lines are chilled to extremely low temperatures. Reflange, Inc. customized an existing piping connector to include a secondary seal more tolerant of severe thermal gradients for Stennis. The T-Con connector solved the problem, and the company is now marketing a commercial version that permits testing, monitoring or collecting any emissions that may escape the primary seal during severe thermal transition.

  7. Piping Connector

    NASA Technical Reports Server (NTRS)

    1994-01-01

    In Stennis Space Center's Component Test Facility, piping lines carry rocket propellants and high pressure cryogenic fuels. When the lines are chilled to a pretest temperature of 400 degrees below zero, ordinary piping connectors can leak. Under contract to Stennis, Reflange, Inc. developed the T-Con connector, which included a secondary seal that tolerates severe temperature change. Because of the limited need for the large and expensive T-Con product, Reflange also developed the less costly E-Con, a smaller more compact design with the same technical advantages as the T-Con.

  8. Finite-temperature Casimir force between perfectly metallic corrugated surfaces

    SciTech Connect

    Sarabadani, Jalal; Miri, MirFaez

    2011-09-15

    We study the Casimir force between two corrugated plates due to thermal fluctuations of a scalar field. For arbitrary corrugations and temperature T, we provide an analytical expression for the Casimir force, which is exact to second order in the corrugation amplitude. We study the specific case of two sinusoidally corrugated plates with corrugation wavelength {lambda}, lateral displacement b, and mean separation H. We find that the lateral Casimir force is F{sub l}(T,H)sin(2{pi}b/{lambda}). In other words, at all temperatures, the lateral force is a sinusoidal function of the lateral shift. In the limit {lambda}>>H, F{sub l}(T{yields}{infinity},H){proportional_to}k{sub B}TH{sup -4}{lambda}{sup -1}. In the opposite limit {lambda}<

  9. Opportunities for Energy Efficiency and Demand Response in Corrugated Cardboard Manufacturing Facilities 

    E-print Network

    Chow, S.; Hackett, B.; Ganji, A. R.

    2005-01-01

    Corrugated cardboard manufacturing is an energy intensive process, in both electric power and steam. Based on the US Census Bureau, there are approximately 1,733 corrugated and solid fiber box manufacturing facilities in the United States...

  10. Solar industrial process steam for a corrugator application

    SciTech Connect

    Semmens, M.; Collaros, G.J.; Fong, A.

    1980-01-01

    Industrial process heat applications have been identified as one of the most promising market areas for the application of solar energy technology. A key application for the use of solar industrial process heat (SIPH) has been identified: cardboard corrugation facilities. DOE has sponsored the design and analysis of a SIPH application at a corrugation operation in Fort Worth, Texas. The preliminary design has suggested that the DOE cost goals can be achieved in the near future with a roof-mounted solar array providing saturated process steam to the manufacturing process. In fact, the capital requirements are less for the roof-mounted (versus ground-mounted) solar system in the Fort Worth area. The corrugator application system preliminary design and analysis are described.

  11. Corrugated quantum well infrared photodetectors for polarization detection C. J. Chen,a)

    E-print Network

    Rokhinson, Leonid

    the recently developed corrugated quantum well infrared photodetector C-QWIP technology to detectCorrugated quantum well infrared photodetectors for polarization detection C. J. Chen,a) K. K. Choi In this letter, we propose the use of the newly developed corrugated quantum well infrared photodetectors C

  12. Scattering Analysis of Open-Ended Circular Waveguide Cavity with Corrugations

    E-print Network

    Myung, Noh-Hoon

    the unit sections are cascaded for an entire scattering characteristic by the corrugated waveguideScattering Analysis of Open-Ended Circular Waveguide Cavity with Corrugations Y. D. Kim, H. Lim, W electromagnetic scattering of an open- ended circular waveguide cavity with corrugations using mode matching

  13. Acoustic radiation efficiency of a periodically corrugated rigid piston

    NASA Astrophysics Data System (ADS)

    Estrada, Héctor; Uris, Antonio; Meseguer, Francisco

    2012-09-01

    The radiation of sound by a periodically corrugated rigid piston is explored using theoretical and numerical approaches and compared with the radiation of flat rigid piston. The depth and the period of the corrugation are considered to be comparable with the wavelength in the surrounding fluid. Radiation enhancement is predicted due to cavity resonances and coherent diffraction. In addition, broad regions of low radiation efficiency are observed. Both effects could have an impact in acoustic transducers technology, either to increase the piston radiated power or to create a source of evanescent acoustic waves. The possibilities offered by this strategy in the nonlinear acoustic regime are also briefly discussed.

  14. Design of a practical dental chair made of corrugated cardboard.

    PubMed

    Goldstein, C M

    1978-12-01

    Directions for the construction of a corrugated cardboard dental chair, useful for mobile clinics and community dentistry programs, are presented. The designers of the cardboard dental chair and I hope that it will be as useful to other members of our profession as it has been to the USC Mobile Dental Clinic. PMID:281443

  15. Porus electrode comprising a bonded stack of pieces of corrugated metal foil

    NASA Technical Reports Server (NTRS)

    Mccallum, J. (inventor)

    1973-01-01

    An electrode suitable for use in an electrochemical cell is described. The electrode is composed of a porous conductive support with a bonded stack of pieces of thin corrugated nickel foil where the corrugations are oriented approximately perpendicular to the sides of the electrode and form an array of passages through the electrode. Active material such as cadmium hydroxide or nickel hydroxide is uniformly distributed within the passages. The support may comprise also a piece of thin flat nickel foil between adjacent pieces of the corrugated foil, forming a barrier between the passages formed on each side of it. Typically the corrugations in the odd corrugated layers are oriented at a small angle from the perpendicular in one direction and the corrugations in the even corrugated layers are oriented at a small angle from the perpendicular in the opposite direction.

  16. Test of superplastically formed corrugated aluminum compression specimens with beaded webs

    NASA Technical Reports Server (NTRS)

    Davis, Randall C.; Royster, Dick M.; Bales, Thomas T.; James, William F.; Shinn, Joseph M., Jr.

    1991-01-01

    Corrugated wall sections provide a highly efficient structure for carrying compressive loads in aircraft and spacecraft fuselages. The superplastic forming (SPF) process offers a means to produce complex shells and panels with corrugated wall shapes. A study was made to investigate the feasibility of superplastically forming 7475-T6 aluminum sheet into a corrugated wall configuration and to demonstrate the structural integrity of the construction by testing. The corrugated configuration selected has beaded web segments separating curved-cap segments. Eight test specimens were fabricated. Two specimens were simply a single sheet of aluminum superplastically formed to a beaded-web, curved-cap corrugation configuration. Six specimens were single-sheet corrugations modified by adhesive bonding additional sheet material to selectively reinforce the curved-cap portion of the corrugation. The specimens were tested to failure by crippling in end compression at room temperature.

  17. Optimization of photonics for corrugated thin-film solar cells

    NASA Astrophysics Data System (ADS)

    Deparis, Olivier; Vigneron, Jean Pol; Agustsson, Otto; Decroupet, Daniel

    2009-11-01

    The amount of solar energy reaching the active (photovoltaic) layer in a thin-film solar cell can be increased by reducing the Fresnel reflection losses at the interfaces. By using corrugated interfaces (at the wavelength scale), adiabatic propagation of the electromagnetic radiation is achieved over a broad wavelength range throughout the structure, which leads to an increase in the light that is absorbed in the active layer and, ultimately, to the improvement of the photovoltaic conversion efficiency. In this article, we have considered the case of corrugated thin-film solar cell structures and we have studied theoretically the optimization of such structures from the point of view of photonics. The focus was put on periodic pyramidal interface corrugations because they were similar to those existing at the surface of corrugated transparent electrodes on which active layers can be deposited. Because of their technological importance, we chose to work with fluorine-doped tin oxide as front electrode material and with amorphous silicon as active material. Using an original three dimensional transfer matrix method, we solved the electromagnetic wave propagation problem in the general case of laterally periodic stratified media and we compared this solution with effective medium approximated solution. On the basis of typical pyramid sizes, we demonstrated, through numerical simulations, the optimization of the global light energy intake by means of corrugations of increasing complexity. The best structures were found to be based on pyramid arrays having subwavelength periods and aspect ratio values close to one. Typically, a pyramidal structure with base and height both equal to 300 nm led to a global energy intake equal to I =0.98 (integrated over the spectral range 400-710 nm), which represented a 24% improvement in comparison with the global energy intake of a planar structure (I =0.79).

  18. Hydrogen sulfide removal from sediment and water in box culverts/storm drains by iron-based granules.

    PubMed

    Sun, J L; Shang, C; Kikkert, G A

    2013-01-01

    A renewable granular iron-based technology for hydrogen sulfide removal from sediment and water in box culverts and storm drains is discussed. Iron granules, including granular ferric hydroxide (GFH), granular ferric oxide (GFO) and rusted waste iron crusts (RWIC) embedded in the sediment phase removed aqueous hydrogen sulfide formed from sedimentary biological sulfate reduction. The exhausted iron granules were exposed to dissolved oxygen and this regeneration process recovered the sulfide removal capacities of the granules. The recovery is likely attributable to the oxidation of the ferrous iron precipitates film and the formation of new reactive ferric iron surface sites on the iron granules and sand particles. GFH and RWIC showed larger sulfide removal capacities in the sediment phase than GFO, likely due to the less ordered crystal structures on their surfaces. This study demonstrates that the iron granules are able to remove hydrogen sulfide from sediment and water in box culverts and storm drains and they have the potential to be regenerated and reused by contacting with dissolved oxygen. PMID:24355850

  19. Flood magnitude and frequency of Jacks Run at the culvert on U.S. Route 206, Southampton Township, Burlington County, New Jersey

    USGS Publications Warehouse

    Barringer, Thomas

    1996-01-01

    Flood magnitude and frequency of Jacks Run at the culvert on U.S. Route 206, Southampton Township, New Jersey, were determined by using the rational method. Flood magnitude and frequency estimates, as well as basin characteristics, are included in this report. The 100-year-flood estimate is 29 cubic feet per second.

  20. Progress Toward Corrugated Feed Horn Arrays in Silicon

    SciTech Connect

    Britton, J.; Yoon, K. W.; Beall, J. A.; Becker, D.; Cho, H. M.; Hilton, G. C.; Niemack, M. D.; Irwin, K. D.

    2009-12-16

    We are developing monolithic arrays of corrugated feed horns fabricated in silicon for dual-polarization single-mode operation at 90, 145 and 220 GHz. The arrays consist of hundreds of platelet feed horns assembled from gold-coated stacks of micro-machined silicon wafers. As a first step, Au-coated Si waveguides with a circular, corrugated cross section were fabricated; their attenuation was measured to be less than 0.15 dB/cm from 80 to 110 GHz at room temperature. To ease the manufacture of horn arrays, electrolytic deposition of Au on degenerate Si without a metal seed layer was demonstrated. An apparatus for measuring the radiation pattern, optical efficiency, and spectral band-pass of prototype horns is described. Feed horn arrays made of silicon may find use in measurements of the polarization anisotropy of the cosmic microwave background radiation.

  1. Corrugations on the Free Surface of Nematic Liquid Crystal Layers

    NASA Astrophysics Data System (ADS)

    Virga, Epifanio G.; Schadt, Martin

    2000-12-01

    In this paper we quantitatively treat an equilibrium problem for the free surface of a monomeric or polymeric nematic liquid crystal layer, which has been suggested by some novel industrial applications. Think of a layer deposited on a plane, rigid substrate, whose optical axis is anchored in such a way that the azimuthal angle is everywhere defined, whereas the polar angle may freely vary. Let further the azimuthal anchoring be discontinuous along a line on the substrate. To accommodate this singularity within a continuous field, the optic axis must flip out of the substrate plane and become orthogonal to it at the anchoring discontinuity. Such a distortion entrains a corrugation on the free surface of the layer. Experimentally, the existence of corrugations at the alignment boundaries of nematic liquid crystal polymer films on single glass substrates is demonstrated by photo-aligning and photo-patterning such films by the linear photopolymerization (LPP)-technology of ROLIC.

  2. Low-loss broadband multimode corrugated waveguide performance

    NASA Astrophysics Data System (ADS)

    Cavallo, A.; Doane, J.; Cutler, R.

    1990-09-01

    A 30-m-long waveguide run using circular corrugated waveguide (i.d.=6.35 cm) with a corrugated period and depth of 254 ?m (0.01 in.) has been fabricated and installed on TFTR (Tokamak Fusion Test Reactor) for use in electron cyclotron emission measurements, and is the first large scale application of this type of waveguide. It is designed for low-loss (<0.01 dB/m) multimode operation between 75 and 575 GHz, and includes three E-plane and four H-plane miter bends. Single-mode measurements at 140 GHz and multimode measurements at 250 GHz indicate that both ohmic losses as well as loss due to mode conversion are negligible with this type of transmission line.

  3. Direct Acceleration of Electrons in a Corrugated Plasma Channel

    SciTech Connect

    Palastro, J. P.; Antonsen, T. M.; Morshed, S.; York, A. G.; Layer, B.; Aubuchon, M.; Milchberg, H. M.; Froula, D. H.

    2009-01-22

    Direct laser acceleration of electrons provides a low power tabletop alternative to laser wakefield accelerators. Until recently, however, direct acceleration has been limited by diffraction, phase matching, and material damage thresholds. The development of the corrugated plasma channel [B. Layer et al., Phys. Rev. Lett. 99, 035001 (2007)] has removed all of these limitations and promises to allow direct acceleration of electrons over many centimeters at high gradients using femtosecond lasers [A. G. York et al., Phys Rev. Lett 100, 195001 (2008), J. P. Palastro et al., Phys. Rev. E 77, 036405 (2008)]. We present a simple analytic model of laser propagation in a corrugated plasma channel and examine the laser-electron beam interaction. Simulations show accelerating gradients of several hundred MeV/cm for laser powers much lower than required by standard laser wakefield schemes. In addition, the laser provides a transverse force that confines the high energy electrons on axis, while expelling low energy electrons.

  4. Ultrasonic pipe assessment

    DOEpatents

    Thomas, Graham H.; Morrow, Valerie L.; Levie, Harold; Kane, Ronald J.; Brown, Albert E.

    2003-12-23

    An ultrasonic pipe or other structure assessment system includes an ultrasonic transducer positioned proximate the pipe or other structure. A fluid connection between the ultrasonic transducer and the pipe or other structure is produced. The ultrasonic transducer is moved relative to the pipe or other structure.

  5. Dispersion of helically corrugated waveguides: Analytical, numerical, and experimental study

    SciTech Connect

    Burt, G.; Ronald, K.; Young, A.R.; Phelps, A.D.R.; Cross, A.W.; Konoplev, I.V.; He, W.; Thomson, J.; Whyte, C.G.; Samsonov, S.V.; Denisov, G.G.; Bratman, V.L.

    2004-10-01

    Helically corrugated waveguides have recently been studied for use in various applications such as interaction regions in gyrotron traveling-wave tubes and gyrotron backward-wave oscillators and as a dispersive medium for passive microwave pulse compression. The paper presents a summary of various methods that can be used for analysis of the wave dispersion of such waveguides. The results obtained from an analytical approach, simulations with the three-dimensional numerical code MAGIC, and cold microwave measurements are analyzed and compared.

  6. Corrugated outer sheath gas-insulated transmission line

    DOEpatents

    Kemeny, George A. (Pittsburgh, PA); Cookson, Alan H. (Churchill Boro, PA)

    1981-01-01

    A gas-insulated transmission line includes two transmission line sections each of which are formed of a corrugated outer housing enclosing an inner high-voltage conductor disposed therein, with insulating support means supporting the inner conductor within the outer housing and an insulating gas providing electrical insulation therebetween. The outer housings in each section have smooth end sections at the longitudinal ends thereof which are joined together by joining means which provide for a sealing fixed joint.

  7. Optimization of a corrugated stiffened composite panel under uniaxial compression

    NASA Technical Reports Server (NTRS)

    Agarwal, B. L.; Sobel, L. H.

    1973-01-01

    An approach of structural optimization has been used to optimize the weight of a simply supported, corrugated hat stiffened composite panel under uniaxial compression. The approach consists of the employment of nonlinear mathematical programming techniques to reach an optimum solution. Some simplifying assumptions are made in the stress analysis to obtain faster convergence to an optimum solution. With these simplifying assumptions the number of unknown design parameters is reduced to twelve.

  8. Interaction of streamers and stationary corrugated ionization waves in semiconductors.

    PubMed

    Kyuregyan, A S

    2014-04-01

    A numerical simulation of evolution of an identical interacting streamers array in semiconductors has been performed using the diffusion-drift approximation and taking into account the impact and tunnel ionization. It has been assumed that the external electric field E0 is static and uniform, the background electrons and holes are absent, the initial avalanches start simultaneously from the nodes of the plane hexagonal lattice, which is perpendicular to the external field, but the avalanches and streamers are axially symmetric within a cylinder of radius R. It has been shown that under certain conditions, the interaction between the streamers leads finally either to the formation of two types of stationary ionization waves with corrugated front or to a stationary plane ionization wave. A diagram of different steady states of this type of waves in the plane of parameter E0,R has been presented, and a qualitative explanation of the plane partition into four different regions has been given. Characteristics of corrugated waves have been studied in detail and discussed in the region of R and E0 large values, in which the maximum field strength at the front is large enough for the tunnel ionization implementation. It has been shown that corrugated waves ionize semiconductors more efficiently than flat ones, especially in relatively weak external fields. PMID:24827322

  9. PROCESSING OF NANOSTRUCTURED COPPER BY REPETITIVE CORRUGATION AND STRAIGHTENING (RCS)

    SciTech Connect

    Zhu, Y.T.; Jiang, H.

    2000-10-01

    A new process, Repetitive Corrugation and Straightening (RCS), has been developed to create bulk, nanostructured copper. In this investigation, a high purity (99.99%). copper bar measuring 6 x 6 x 50 mm with an average grain size of 765 {micro}m was used as the starting material. It was repetitively corrugated and straightened for 14 times with 90{degree} rotations along its longitudinal axis between consecutive corrugation-straightening cycles. The copper was cooled to below room temperature before each RCS cycle. The grain size obtained after the RCS process was in the range of twenty to a few hundred nanometers, and microhardness was increased by 100%. Both equilibrium and non-equilibrium grain boundaries are observed. This work demonstrates the capability of the RCS process in refining grain size of metal materials. The RCS process can be easily adapted to large-scale industrial production and has the potential to pave the way to large-scale structural applications of nanostructured materials.

  10. Spectral gap induced by structural corrugation in armchair graphene nanoribbons

    NASA Astrophysics Data System (ADS)

    Costamagna, S.; Hernandez, O.; Dobry, A.

    2010-03-01

    We study the effects of the structural corrugation or rippling on the electronic properties of undoped armchair graphene nanoribbons (AGNRs). First, reanalyzing the single corrugated graphene layer we find that the two inequivalent Dirac points (DPs) move away from each other. Futhermore, the Fermi velocity vF decreases when the rippling increases. Regarding the AGNRs, whose metallic behavior depends on their widths, we analyze, in particular, the case of the zero-gap band-structure AGNRs. By solving the Dirac equation with adequate boundary conditions we show that, due to the shifting of the DP, a gap opens up in the spectra. This gap scales with the square of the rate between the height and the wavelength of the deformation. We confirm this prediction by an exact numerical solution of the finite width rippled AGNR. Moreover, we find that the quantum conductance, calculated by the nonequilibrium Green’s function technique, vanishes when the gap opens up. The main conclusion of our results is that a conductance gap should appear for all undoped corrugated AGNR, independently of their widths.

  11. Non-contact gears: II. Casimir torque between concentric corrugated cylinders for the scalar case

    E-print Network

    Ines Cavero-Pelaez; Kimball A. Milton; Prachi Parashar; K. V. Shajesh

    2008-07-03

    The Casimir interaction between two concentric corrugated cylinders provides the mechanism for non-contact gears. To this end, we calculate the Casimir torque between two such cylinders, described by $\\delta$-potentials, which interact through a scalar field. We derive analytic expressions for the Casimir torque for the case when the corrugation amplitudes are small in comparison to the corrugation wavelengths. We derive explicit results for the Dirichlet case, and exact results for the weak coupling limit, in the leading order. The results for the corrugated cylinders approach the corresponding expressions for the case of corrugated parallel plates in the limit of large radii of cylinders (relative to the difference in their radii) while keeping the corrugation wavelength fixed.

  12. Assessment of scour-critical data collected at selected bridges and culverts in South Carolina, 1990-92

    USGS Publications Warehouse

    Hurley, N.M., Jr.

    1996-01-01

    Data at bridges and culverts were collected at 3,506 stream crossings in South Carolina during 1990-92. The data include general information unique to the structure; structural data; and hydraulic, geomorphic, and vegetation information. The data are stored in the U.S. Geological Survey South Carolina District Bridge-Scour Data Base. Observed- and potential-scour indexes were computed from the applicable data variables. Sites with observed-scour indexes exceeding ten and (or) potential-scour indexes exceeding 20 are considered to have significant scour-related problems. Of the 3,506 sites inspected, 257 sites had an observed-scour index exceeding ten, 214 sites had a potential-scour index exceeding 20, and 85 sites had observed- and potential-scour indexes exceeding both threshold values.

  13. Experimental Investigation of the Strength of Multiweb Beams with Corrugated Webs

    NASA Technical Reports Server (NTRS)

    Fraser, Allister F

    1956-01-01

    The results of an experimental investigation of the strength of multiweb beams with corrugated webs are reported. Included in the investigation were two types of connection between the web and the skin. A comparison between the structural efficiency of corrugated-web and channel-web multiweb beams is presented, and it is shown that, for a considerable range of the structural index, corrugated-web beams can be built which are structurally more efficient than channel-web beams.

  14. Flexible ocean upwelling pipe

    DOEpatents

    Person, Abraham (Los Alamitos, CA)

    1980-01-01

    In an ocean thermal energy conversion facility, a cold water riser pipe is releasably supported at its upper end by the hull of the floating facility. The pipe is substantially vertical and has its lower end far below the hull above the ocean floor. The pipe is defined essentially entirely of a material which has a modulus of elasticity substantially less than that of steel, e.g., high density polyethylene, so that the pipe is flexible and compliant to rather than resistant to applied bending moments. The position of the lower end of the pipe relative to the hull is stabilized by a weight suspended below the lower end of the pipe on a flexible line. The pipe, apart from the weight, is positively buoyant. If support of the upper end of the pipe is released, the pipe sinks to the ocean floor, but is not damaged as the length of the line between the pipe and the weight is sufficient to allow the buoyant pipe to come to a stop within the line length after the weight contacts the ocean floor, and thereafter to float submerged above the ocean floor while moored to the ocean floor by the weight. The upper end of the pipe, while supported by the hull, communicates to a sump in the hull in which the water level is maintained below the ambient water level. The sump volume is sufficient to keep the pipe full during heaving of the hull, thereby preventing collapse of the pipe.

  15. On the isothermal geometry of corrugated graphene sheets

    E-print Network

    Andrzej Trzesowski

    2014-12-22

    Variational geometries describing corrugated graphene sheets are proposed. The isothermal thermomechanical properties of these sheets are described by a 2-dimensional Weyl space. The equation that couples the Weyl geometry with isothermal distributions of the temperature of graphene sheets, is formulated. This material space is observed in a 3-dimensional orthogonal configurational point space as regular surfaces which are endowed with a thermal state vector field fulfilling the isothermal thermal state equation. It enables to introduce a non-topological dimensionless thermal shape parameter of non-developable graphene sheets. The properties of the congruence of lines generated by the thermal state vector field are discussed.

  16. Excitation of multiple surface-plasmon-polariton waves guided by the periodically corrugated interface

    E-print Network

    Excitation of multiple surface-plasmon-polariton waves guided by the periodically corrugated The excitation of multiple surface-plasmon-polariton (SPP) waves guided by the periodically corrugated interface on the propagation and excitation of surface-plasmon-polariton (SPP) waves guided by the inter- face of a homogeneous

  17. Role of substrate corrugation in helium monolayer solidification M. E. Pierce and E. Manousakis

    E-print Network

    Manousakis, Efstratios

    that the equilibrium phase is the 3 3 commensurate solid phase that is well known from experiment. The melting behavior should consist of a commensurate solid with vacancies. When the temperature is raised, the solid melts of substrate corrugations on the phase diagram. When no corrugations are present, the equilibrium state

  18. Quantized systems with randomly corrugated walls and interfaces A. E. Meyerovich and A. Stepaniants

    E-print Network

    Meyerovich, Alex

    Effect of scattering by random surface inhomogeneities on transport along the walls and localization characteristics of weak roughness and can be used as a general boundary condition on the corrugated surfaces scattering. More precisely, we consider effects of scattering by random surface corrugation without energy

  19. Pipe-to-pipe impact program

    SciTech Connect

    Alzheimer, J.M.; Bampton, M.C.C.; Friley, J.R.; Simonen, F.A.

    1984-06-01

    This report documents the tests and analyses performed as part of the Pipe-to-Pipe Impact (PTPI) Program at the Pacific Northwest Laboratory. This work was performed to assist the NRC in making licensing decisions regarding pipe-to-pipe impact events following postulated breaks in high energy fluid system piping. The report scope encompasses work conducted from the program's start through the completion of the initial hot oil tests. The test equipment, procedures, and results are described, as are analytic studies of failure potential and data correlation. Because the PTPI Program is only partially completed, the total significance of the current test results cannot yet be accurately assessed. Therefore, although trends in the data are discussed, final conclusions and recommendations will be possible only after the completion of the program, which is scheduled to end in FY 1984.

  20. Heat pipes. [technology utilization

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The development and use of heat pipes are described, including space requirements and contributions. Controllable heat pipes, and designs for automatically maintaining a selected constant temperature, are discussed which would add to the versatility and usefulness of heat pipes in industrial processing, manufacture of integrated circuits, and in temperature stabilization of electronics.

  1. Plane-wave diffraction at the periodically corrugated boundary of vacuum and a negative-phase-velocity material.

    PubMed

    Depine, Ricardo A; Lakhtakia, Akhlesh

    2004-05-01

    Considering the diffraction of a plane wave by a periodically corrugated half-space, we show that the transformation of the refracting medium from positive (negative) phase velocity to negative (positive) phase velocity type has an influence on the diffraction efficiencies. This effect increases with increasing corrugation depth, owing to the presence of evanescent waves in the troughs of the corrugated interface. PMID:15244981

  2. Flood magnitude and frequency of Franklin Pond tributary at the culvert on New Jersey Route 23, Franklin Borough, Sussex County, New Jersey

    USGS Publications Warehouse

    Barringer, Thomas

    1996-01-01

    Flood magnitude and frequency values are presented for Franklin Pond tributary at the culvert at milepost 32.2 of New Jersey Route 23, Franklin Borough, New Jersey. The values were determined by using the New Jersey Department of Environmental Protection Special Report 38 method. A description of the drainage-basin characteristics also is included in this report. The 100-year-flood estimate is 218 cubic feet per second.

  3. Flood magnitude and frequency of Little Timber Creek at the culvert on Interstate Route 295, Haddon Heights Township, Camden County, New Jersey

    USGS Publications Warehouse

    Barringer, T.H.

    1996-01-01

    The magnitude and frequency of floods at the Little Timber Creek at the culvert on Interstate 295, at milepost 28.9, in Haddon Heights Township, New Jersey, were determined by using the New Jersey Department of Environmental Protection Special Report 38 method. Flood-magnitude and -frequency estimates, as well as drainage-basin characteristics, are included in this report. The 100-year-flood estimate is 770 cubic feet per second.

  4. Flood magnitude and frequency of Black Creek at the culvert on New Jersey Route 94, Vernon Township, Sussex County, New Jersey

    USGS Publications Warehouse

    Barringer, T.H.

    1996-01-01

    The magnitude and frequency of floods at Black Creek tributary at the culvert on New Jersey Route 94 at milepost 43.0 in Vernon Township, New Jersey, were determined by using the New Jersey Department of Environmental Protection Special Report 38 method. Estimates of flood magnitude and frequency calculated by the Special Report 38 method, as well as drainage-basin characteristics, are included in this report. The 100-year-flood estimate is 261 cubic feet per second.

  5. Overall Thermal Performance of Flexible Piping Under Simulated Bending Conditions

    NASA Technical Reports Server (NTRS)

    Fesmire, James E.; Augustynowicz, S. D.; Demko, J. A.; Thompson, Karen (Technical Monitor)

    2001-01-01

    Flexible, vacuum-insulated transfer lines for low-temperature applications have higher thermal losses than comparable rigid lines. Typical flexible piping construction uses corrugated tubes, inner and outer, with a multilayer insulation (MLI) system in the annular space. Experiments on vacuum insulation systems in a flexible geometry were conducted at the Cryogenics Test Laboratory of NASA Kennedy Space Center. The effects of bending were simulated by causing the inner tube to be eccentric with the outer tube. The effects of spacers were simulated in a controlled way by inserting spacer tubes for the length of the cylindrical test articles. Two material systems, standard MLI and a layered composite insulation (LCI), were tested under the full range of vacuum levels using a liquid nitrogen boiloff calorimeter to determine the apparent thermal conductivity (k-value). The results indicate that the flexible piping under simulated bending conditions significantly degrades the thermal performance of the insulation system. These data are compared to standard MLI for both straight and flexible piping configurations. The definition of an overall k-value for actual field installations (k(sub oafi)) is described for use in design and analysis of cryogenic piping systems.

  6. Corrugated Waveguide Mode Content Analysis Using Irradiance Moments

    PubMed Central

    Jawla, Sudheer K.; Shapiro, Michael A.; Idei, Hiroshi; Temkin, Richard J.

    2015-01-01

    We present a novel, relatively simple method for determining the mode content of the linearly polarized modes of a corrugated waveguide using the moments of the intensity pattern of the field radiated from the end of the waveguide. This irradiance moment method is based on calculating the low-order irradiance moments, using measured intensity profiles only, of the radiated field from the waveguide aperture. Unlike the phase retrieval method, this method does not use or determine the phase distribution at the waveguide aperture. The new method was benchmarked numerically by comparison with sample mode mixtures. The results predict less than ±0.7% error bar in the retrieval of the mode content. The method was also tested using high-resolution experimental data from beams radiated from 63.5 mm and 19 mm corrugated waveguides at 170 and 250 GHz, respectively. The results showed a very good agreement of the mode content retrieved using the irradiance moment method versus the phase retrieval technique. The irradiance moment method is most suitable for cases where the modal power is primarily in the fundamental HE11 mode, with <8% of the power in high-order modes. PMID:25821260

  7. BNL piping research

    SciTech Connect

    Bezler, P.; Subudhi, M.; Wang, Y.K.; Shteyngart, S.

    1985-01-01

    Brookhaven National Laboratory (BNL) has assisted in the development of methods to evaluate the analysis methods used by industry to qualify nuclear power piping. Through FY 1985 these efforts were conducted under the Mechanical Piping Benchmarks project while current and future efforts will be performed under the Combination Procedures for piping project. Under these projects BNL has developed analytical benchmark problems for piping systems evaluated using uniform or independent support motion response spectrum methods, investigated the adequacy and limitations of linear piping analysis methods by comparison to test results and evaluated and developed criteria for new and alternate methods of analysis. A summary description of the status of these efforts is provided.

  8. Modeling of a corrugated dielectric elastomer actuator for artificial muscle applications

    NASA Astrophysics Data System (ADS)

    Kadooka, Kevin; Taya, Minoru; Naito, Keishi; Saito, Makoto

    2015-04-01

    Dielectric elastomer actuators have many advantages, including light weight, simplicity, high energy density, and silent operation. These features make them suitable to replace conventional actuators and transducers, especially in artificial muscle applications where large contractile strains are necessary for lifelike motions. This paper will introduce the concept of a corrugated dielectric elastomer actuator (DEA), which consists of dielectric elastomer (DE) laminated to a thin elastic layer to induce bending motion at each of the corrugations, resulting in large axial deformation. The location of the DE and elastic layers can be configured to provide tensile or compressive axial strain. Such corrugated DE actuators are also highly scalable: linking multiple actuators in series results in greater deformation, whereas multiple actuators in parallel results in larger force output. Analytical closed-form solutions based on linear elasticity were derived for the displacement and force output of curved unimorph and corrugated DEA, both consisting of an arbitrary number of lamina. A total strain energy analysis and Castigiliano's theorem were used to predict the nonlinear force-displacement behavior of the corrugated actuator. Curved unimorph and corrugated DEA were fabricated using VHB F9469PC as the DE material. Displacement of the actuators observed during testing agreed well with the modeling results. Large contractile strain (25.5%) was achieved by the corrugated DEA. Future work includes investigating higher performance DE materials such as plasticized PVDF terpolymers, processed by thin film deposition methods.

  9. Research on a 170?GHz, 2?MW coaxial cavity gyrotron with inner-outer corrugation

    SciTech Connect

    Hou, Shenyong; Yu, Sheng; Li, Hongfu

    2015-03-15

    In this paper, a coaxial cavity gyrotron with inner-outer corrugation is researched. The electron kineto-equations and the first order transmission line equations of the gyrotron are derived from Lorentz force equation and the transmission line theory, respectively. And then, a 2?MW, 170?GHz coaxial cavity gyrotron with inner-outer corrugation is designed. By means of numerical calculation, the beam-wave interaction of the coaxial cavity gyrotron with inner-outer corrugation is investigated. Results show that the efficient and the outpower of the gyrotron are 42.3% and 2.38?MW, respectively.

  10. Gyrokinetic simulations of off-axis minimum-q profile corrugations

    SciTech Connect

    Waltz, R.E.; Austin, M.E.; Burrell, K.H.; Candy, J.

    2006-05-15

    Quasiequilibrium radial 'profile corrugations' in the electron temperature gradient are found at lowest-order singular surfaces in global gyrokinetic code simulations of both monotonic-q and off-axis minimum-q discharges. The profile corrugations in the temperature and density gradients are time-averaged components of zonal flows. The m/n=2/1 electron temperature gradient corrugation is measurably large and appears to trigger an internal transport barrier as the off-axis minimum-q=2 surfaces enter the plasma.

  11. The effects of cell face curvature and corrugations on the stiffness and strength of metallic foams

    SciTech Connect

    Simone, A.E.; Gibson, L.J.

    1998-07-01

    The measured mechanical properties of conventional lightweight metallic foams fall far short of those predicted by idealized models for closed cell foams. Their poor mechanical performance can be attributed, to a large extent, to curved and corrugated cell faces present within the foams. Idealized honeycombs and foams with idealized cell structure and curved or corrugated cell edges and faces are modeled using finite elements. The elastic modulus and plastic collapse stress of these honeycombs and foams are calculated relative to those of a comparable cellular material model with flat cell edges and faces. The results are presented in terms of the radius of curvature and the amplitude and frequency of the corrugation.

  12. Quantum conductance gap in corrugated armchair graphene nanoribbons

    NASA Astrophysics Data System (ADS)

    Dobry, Ariel; Hernandez, Ober; Costamagna, Sebastian

    2010-03-01

    We study the effects of the structural corrugation or rippling on the electronic properties of both layers and nanoribbons of graphene. For the wrapped sheet we find that the two Dirac points approach each other and that the Fermi velocity decrease by increasing rippling. Regarding the nano-ribbons, we focus on the armchair border type nanoribbons (AGNR) whose metallic behaviour depends on their width. Particularly we analyze the case of the zero gap band-structure AGNRs which present the known Dirac point at the Fermi level of the undoped samples. The shifting of DP due the rippling produce a drastic change opening a gap in the spectra. We show that this gap scale with the rate of the high and the wavelength of the deformation. The quantum conductance vanish when the gap open. Our results imply a conductance gap for all AGNR independent of their width.

  13. A Large L-Band Rectangular Corrugated Horn

    SciTech Connect

    Witebsky, C.; Smoot, G.F.; Levin, S.; Bensadoun, M.

    1987-01-01

    This paper describes a lightweight, corrugated-horn antenna, constructed from sheet metal. Over a 1.3-1.7 GHz operating band, its half-power beam width is approximately 20{sup o} in the E-plane and varies from 17{sup o} to 13{sup o} in the H-plane. Quarter-wave choke slots at the aperture help to reduce the E-plane sidelobes below -55 dB at angles greater than 90{sup o}, while the H-plane sidelobes lie in that range both with and without choke slots. Return loss throughout the operating band is -25 dB or below. Critical dimensions are provided, together with useful guidelines for designing similar antennas.

  14. A nonlinear investigation of corrugation instabilities in magnetic accretion shocks

    NASA Astrophysics Data System (ADS)

    Ernst, Scott

    2011-05-01

    Accretion shock waves are present in many important astrophysical systems and have been a focus of research for decades. These investigations provide a large body of understanding as to the nature, characteristics, and evolutionary behaviors of accretion shock waves over a wide range of conditions. However, largely absent are investigations into the properties of accretion shock waves in the presence of strong magnetic fields. In such cases these strong magnetic fields can significantly alter the stability behaviors and evolution of the accretion shock wave through the production and propagation of magnetic waves as well as magnetically constrained advection. With strong magnetic fields likely found in a number of accretion shock systems, such as compact binary and protostellar systems, a better understanding of the behaviors of magnetic accretion shock waves is needed. A new magnetohydrodynamics simulation tool, IMOGEN, was developed to carry out an investigation of instabilities in strong, slow magnetic accretion shocks by modelling their long-term, nonlinear evolution. IMOGEN implements a relaxed, second-order, total variation diminishing, monotonic upwind scheme for conservation laws and incorporates a staggered-grid constrained transport scheme for magnetic advection. Through the simulated evolution of magnetic accretion shocks over a wide range of initial conditions, it has been shown, for sufficiently high magnetic field strengths, that magnetic accretion shocks are generally susceptible to corrugation instabilities, which arise in the presence of perturbations of the initial shock front. As these corrugation instabilities grow, they manifestas magnetic wave propagation in the upstream region of the accretion column, which propagate away from the accretion shock front, and as density columns, or fingers, that grow into the higher density downstream flow, defined and constrained by current loops created during the early evolution of the instability.

  15. Deployable Heat Pipe Radiator

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1975-01-01

    A 1.2- by 1.8-m variable conductance heat pipe radiator was designed, built, and tested. The radiator has deployment capability and can passively control Freon-21 fluid loop temperatures under varying loads and environments. It consists of six grooved variable conductance heat pipes attached to a 0.032-in. aluminum panel. Heat is supplied to the radiator via a fluid header or a single-fluid flexible heat pipe header. The heat pipe header is an artery design that has a flexible section capable of bending up to 90 degrees. Radiator loads as high as 850 watts were successfully tested. Over a load variation of 200 watts, the outlet temperature of the Freon-21 fluid varied by 7 F. An alternate control system was also investigated which used a variable conductance heat pipe header attached to the heat pipe radiator panel.

  16. Abrasion resistant heat pipe

    DOEpatents

    Ernst, Donald M. (Leola, PA)

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  17. Abrasion resistant heat pipe

    DOEpatents

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  18. Internal pipe attachment mechanism

    DOEpatents

    Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.

    1994-12-13

    An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.

  19. External artery heat pipe

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)

    1989-01-01

    An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

  20. Heat Pipe Materials Compatibility

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.; Fleischman, G. L.; Luedke, E. E.

    1976-01-01

    An experimental program to evaluate noncondensable gas generation in ammonia heat pipes was completed. A total of 37 heat pipes made of aluminum, stainless steel and combinations of these materials were processed by various techniques, operated at different temperatures and tested at low temperature to quantitatively determine gas generation rates. In order of increasing stability are aluminum/stainless combination, all aluminum and all stainless heat pipes. One interesting result is the identification of intentionally introduced water in the ammonia during a reflux step as a means of surface passivation to reduce gas generation in stainless-steel/aluminum heat pipes.

  1. Pipe crawler apparatus

    DOEpatents

    Hovis, Gregory L. (North Augusta, SC); Erickson, Scott A. (Augusta, GA); Blackmon, Bruce L. (Aiken, SC)

    2002-01-01

    A pipe crawler apparatus particularly useful for 3-inch and 4-inch diameter pipes is provided. The pipe crawler apparatus uses a gripping apparatus in which a free end of a piston rod is modified with a bearing retaining groove. Bearings, placed within the groove, are directed against a camming surface of three respective pivoting support members. The non-pivoting ends of the support members carry a foot-like gripping member that, upon pivoting of the support member, engages the interior wall of the pipe.

  2. Heat Pipe Planets

    NASA Technical Reports Server (NTRS)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2014-01-01

    When volcanism dominates heat transport, a terrestrial body enters a heat-pipe mode, in which hot magma moves through the lithosphere in narrow channels. Even at high heat flow, a heat-pipe planet develops a thick, cold, downwards-advecting lithosphere dominated by (ultra-)mafic flows and contractional deformation at the surface. Heat-pipes are an important feature of terrestrial planets at high heat flow, as illustrated by Io. Evidence for their operation early in Earth's history suggests that all terrestrial bodies should experience an episode of heat-pipe cooling early in their histories.

  3. Introduction to Heat Pipes

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. NCTS 21070-15. Course Description: This course will present operating principles of the heat pipe with emphases on the underlying physical processes and requirements of pressure and energy balance. Performance characterizations and design considerations of the heat pipe will be highlighted. Guidelines for thermal engineers in the selection of heat pipes as part of the spacecraft thermal control system, testing methodology, and analytical modeling will also be discussed.

  4. Bending Tests of Circular Cylinders of Corrugated Aluminum-alloy Sheet

    NASA Technical Reports Server (NTRS)

    Buckwalter, John C; Reed, Warren D; Niles, Alfred S

    1937-01-01

    Bending tests were made of two circular cylinders of corrugated aluminum-alloy sheet. In each test failure occurred by bending of the corrugations in a plane normal to the skin. It was found, after analysis of the effect of short end bays, that the computed stress on the extreme fiber of a corrugated cylinder is in excess of that for a flat panel of the same basic pattern and panel length tested as a pin-ended column. It is concluded that this increased strength was due to the effects of curvature of the pitch line. It is also concluded from the tests that light bulkheads closely spaced strengthen corrugated cylinders very materially.

  5. Heat transfer characteristics of a back-corrugated absorber surface for solar air collectors

    NASA Astrophysics Data System (ADS)

    Shockey, K. A.; Pearson, J. T.; Dewitt, D. P.

    1981-11-01

    The present study experimentally examines a back-corrugated absorber-convector comprised of a rectangularly corrugated plate attached to the back side of a flat absorber plate with a high temperature, high strength adhesive. The upper surface is subjected to a heat flux from a blanket-type electric heater simulating solar irradiation. The corrugated plate configuration creates two parallel airflow channel types. The two channels have different geometries and, therefore, may have different heat transfer characteristics. An apparatus was designed to determine the local convective heat transfer coefficients along each of the channels. The results show that the back-corrugated absorber-convector has much better thermal performance than the simple flat-plate absorber-convector, mainly because of the increased connective heat transfer area.

  6. Development of a model for flaming combustion of double-wall corrugated cardboard

    NASA Astrophysics Data System (ADS)

    McKinnon, Mark B.

    Corrugated cardboard is used extensively in a storage capacity in warehouses and frequently acts as the primary fuel for accidental fires that begin in storage facilities. A one-dimensional numerical pyrolysis model for double-wall corrugated cardboard was developed using the Thermakin modeling environment to describe the burning rate of corrugated cardboard. The model parameters corresponding to the thermal properties of the corrugated cardboard layers were determined through analysis of data collected in cone calorimeter tests conducted with incident heat fluxes in the range 20--80 kW/m 2. An apparent pyrolysis reaction mechanism and thermodynamic properties for the material were obtained using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The fully-parameterized bench-scale model predicted burning rate profiles that were in agreement with the experimental data for the entire range of incident heat fluxes, with more consistent predictions at higher heat fluxes.

  7. 5. Detail, 5panel door and corrugated metal siding, Oil House, ...

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

    5. Detail, 5-panel door and corrugated metal siding, Oil House, Southern Pacific Railroad Carlin Shops, southwest facade, view to northeast (210mm lens). - Southern Pacific Railroad, Carlin Shops, Oil House, Foot of Sixth Street, Carlin, Elko County, NV

  8. Similar Mechanisms Underlie the Detection of Horizontal and Vertical Disparity Corrugations

    PubMed Central

    Witz, Nirel; Zhou, Jiawei; Hess, Robert F.

    2014-01-01

    Our aim was to compare sensitivity for horizontal and vertical disparity corrugations and to resolve whether these stimuli are processed by similar or radically different underlying mechanisms. We measure global disparity sensitivity as a function of carrier spatial frequency for equi-detectable carriers and found a similar optimal carrier relationship for vertical and horizontal stimuli. Sensitivity as a function of corrugation spatial frequency for stimuli of comparable spatial summation and composed of optimal, equi-detectable narrowband carriers did not significantly differ for vertical and horizontal stimuli. A small anisotropy was revealed when fixed, high contrast broadband carriers were used. In a separate discrimination-at-threshold experiment, multiple mechanisms of similar tuning were revealed to underlie the detection of both vertical and horizontal disparity corrugations. We conclude that the processing of the horizontal and vertical disparity corrugations occurs along similar lines. PMID:24404193

  9. Failure modes and design optimization for re-usable corrugated cases 

    E-print Network

    Karuppoor, Srinand S.

    1997-01-01

    The objective of this thesis is to study and analyze the distribution and usage of reusable corrugated cardboard cases in the delivery of the product within the Frito-Lay system. The studies conducted looked at the various ...

  10. Eikonal approximation in atom-surface scattering: Effects of a corrugated attractive well J. R. Manson

    E-print Network

    Manson, Joseph R.

    and not by the smaller Mg ions. Since the repulsive force on an incoming atomic scattering projectile is due to Pauli to the oxygen atom. However, in the well one would also expect a strong corrugation of the at- tractive

  11. Leaky-Wave Radiations by Modulating Surface Impedance on Subwavelength Corrugated Metal Structures

    E-print Network

    Cai, Ben Geng; Ma, Hui Feng; Jiang, Wei Xiang; Cheng, Qiang; Cui, Tie Jun

    2016-01-01

    One-dimensional (1D) subwavelength corrugated metal structures has been described to support spoof surface plasmon polaritons (SPPs). Here we demonstrate that a modulated 1D subwavelength corrugated metal structure can convert spoof SPPs to propagating waves. The structure is fed at the center through a slit with a connected waveguide on the input side. The subwavelength corrugated metal structure on the output surface is regarded as metasurface and modulated periodically to realize the leaky-wave radiation at the broadside. The surface impedance of the corrugated metal structure is modulated by using cosine function and triangle-wave function, respectively, to reach the radiation effect. Full wave simulations and measuremental results are presented to validate the proposed design.

  12. Reconciling the electronic and geometric corrugations of the hexagonal boron nitride and graphene nanomeshes

    NASA Astrophysics Data System (ADS)

    McKee, William C.; Meunier, Vincent; Xu, Ye

    2015-12-01

    Monolayer hexagonal boron nitride on Rh(111) and graphene on Ru(0001) illustrate a trend of divergence between the density functional theory (DFT) calculated geometric corrugation, and scanning tunneling microscope (STM) measured apparent corrugation, of metal-supported 2D films that feature chemically distinct regions. Notably, the geometric and apparent corrugations differ by up to 2 Å for boron nitride/Rh(111), whereas both the DFT-simulated and the experimentally observed STM images agree in the apparent corrugation over a wide range of bias voltages. The disparity is due to unequal contributions of the low/high-lying atoms to the local density of states in the vicinity of the Fermi level. This phenomenon has important implications for the structural characterization of certain supported 2D films, which are being explored for novel electronic and material applications.

  13. Numerical and Experimental Investigations on Mechanical Behavior of Composite Corrugated Core

    NASA Astrophysics Data System (ADS)

    Dayyani, Iman; Ziaei-Rad, Saeed; Salehi, Hamid

    2012-06-01

    Tensile and flexural characteristics of corrugated laminate panels were studied using numerical and analytical methods and compared with experimental data. Prepreg laminates of glass fiber plain woven cloth were hand-laid by use of a heat gun to ease the creation of the panel. The corrugated panels were then manufactured by using a trapezoidal machined aluminium mould. First, a series of simple tension tests were performed on standard samples to evaluate the material characteristics. Next, the corrugated panels were subjected to tensile and three-point bending tests. The force-displacement graphs were recorded. Numerical and analytical solutions were proposed to simulate the mechanical behavior of the panels. In order to model the energy dissipation due to delamination phenomenon observed in tensile tests in all members of corrugated core, plastic behavior was assigned to the whole geometry, not only to the corner regions. Contrary to the literature, it is shown that the three-stage mechanical behavior of composite corrugated core is not confined to aramid reinforced corrugated laminates and can be observed in other types such as fiber glass. The results reveal that the mechanical behavior of the core in tension is sensitive to the variation of core height. In addition, for the first time, the behavior of composite corrugated core was studied and verified in bending. Finally, the analytical and numerical results were validated by comparing them with experimental data. A good degree of correlation was observed which showed the suitability of the finite element model for predicting the mechanical behavior of corrugated laminate panels.

  14. These Pipes Are "Happening"

    ERIC Educational Resources Information Center

    Skophammer, Karen

    2010-01-01

    The author is blessed with having the water pipes for the school system in her office. In this article, the author describes how the breaking of the pipes had led to a very worthwhile art experience for her students. They practiced contour and shaded drawing techniques, reviewed patterns and color theory, and used their reasoning skills--all while…

  15. Extendable pipe crawler

    DOEpatents

    Hapstack, M.

    1991-05-28

    A pipe crawler is described having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by inchworm'-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward. 5 figures.

  16. Extendable pipe crawler

    DOEpatents

    Hapstack, Mark (North Augusta, SC)

    1991-01-01

    A pipe crawler having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by "inchworm"-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward.

  17. Measurement of washboarding of corrugated cardboard using digital image profilometry

    NASA Astrophysics Data System (ADS)

    Reich, Michael H.; Allan, Russell

    1996-02-01

    A prototype digital image profilometer has been constructed to measure washboarding of corrugated cardboard. The profilometer consists of a diode laser, collimating optics, a grating and CCD camera. The laser beam is projected through the grating to produce straight bars that illuminate the sample at 90 degrees to the undulations. The deformation of the bars projected onto the sample, tilted at 75 degrees to the camera, is analyzed using Fourier analysis to produce a surface profile of the sample. A series of 1-D Fourier transforms are calculated from the intensity profile for successive scan lines at right angles to the bars projected onto the surface. The average depth profile for each scan line is then derived, after phase unwrapping, from the phase of the dominant frequency of the spatial frequency spectrum. The profilometer can reliably measure washboarding to a depth resolution of less than 10 microns over an area of 20 cm by 20 cm in less than 4 seconds on a 486DX2/66 computer.

  18. Corrugator activity confirms immediate negative affect in surprise

    PubMed Central

    Topolinski, Sascha; Strack, Fritz

    2015-01-01

    The emotion of surprise entails a complex of immediate responses, such as cognitive interruption, attention allocation to, and more systematic processing of the surprising stimulus. All these processes serve the ultimate function to increase processing depth and thus cognitively master the surprising stimulus. The present account introduces phasic negative affect as the underlying mechanism responsible for this switch in operating mode. Surprising stimuli are schema-discrepant and thus entail cognitive disfluency, which elicits immediate negative affect. This affect in turn works like a phasic cognitive tuning switching the current processing mode from more automatic and heuristic to more systematic and reflective processing. Directly testing the initial elicitation of negative affect by surprising events, the present experiment presented high and low surprising neutral trivia statements to N = 28 participants while assessing their spontaneous facial expressions via facial electromyography. High compared to low surprising trivia elicited higher corrugator activity, indicative of negative affect and mental effort, while leaving zygomaticus (positive affect) and frontalis (cultural surprise expression) activity unaffected. Future research shall investigate the mediating role of negative affect in eliciting surprise-related outcomes. PMID:25762956

  19. Corrugator activity confirms immediate negative affect in surprise.

    PubMed

    Topolinski, Sascha; Strack, Fritz

    2015-01-01

    The emotion of surprise entails a complex of immediate responses, such as cognitive interruption, attention allocation to, and more systematic processing of the surprising stimulus. All these processes serve the ultimate function to increase processing depth and thus cognitively master the surprising stimulus. The present account introduces phasic negative affect as the underlying mechanism responsible for this switch in operating mode. Surprising stimuli are schema-discrepant and thus entail cognitive disfluency, which elicits immediate negative affect. This affect in turn works like a phasic cognitive tuning switching the current processing mode from more automatic and heuristic to more systematic and reflective processing. Directly testing the initial elicitation of negative affect by surprising events, the present experiment presented high and low surprising neutral trivia statements to N = 28 participants while assessing their spontaneous facial expressions via facial electromyography. High compared to low surprising trivia elicited higher corrugator activity, indicative of negative affect and mental effort, while leaving zygomaticus (positive affect) and frontalis (cultural surprise expression) activity unaffected. Future research shall investigate the mediating role of negative affect in eliciting surprise-related outcomes. PMID:25762956

  20. Dispersionless Manipulation of Reflected Acoustic Wavefront by Subwavelength Corrugated Surface

    NASA Astrophysics Data System (ADS)

    Zhu, Yi-Fan; Zou, Xin-Ye; Li, Rui-Qi; Jiang, Xue; Tu, Juan; Liang, Bin; Cheng, Jian-Chun

    2015-06-01

    Free controls of optic/acoustic waves for bending, focusing or steering the energy of wavefronts are highly desirable in many practical scenarios. However, the dispersive nature of the existing metamaterials/metasurfaces for wavefront manipulation necessarily results in limited bandwidth. Here, we propose the concept of dispersionless wavefront manipulation and report a theoretical, numerical and experimental work on the design of a reflective surface capable of controlling the acoustic wavefront arbitrarily without bandwidth limitation. Analytical analysis predicts the possibility to completely eliminate the frequency dependence with a specific gradient surface which can be implemented by designing a subwavelength corrugated surface. Experimental and numerical results, well consistent with the theoretical predictions, have validated the proposed scheme by demonstrating a distinct phenomenon of extraordinary acoustic reflection within an ultra-broad band. For acquiring a deeper insight into the underlying physics, a simple physical model is developed which helps to interpret this extraordinary phenomenon and predict the upper cutoff frequency precisely. Generations of planar focusing and non-diffractive beam have also been exemplified. With the dispersionless wave-steering capability and deep discrete resolution, our designed structure may open new avenue to fully steer classical waves and offer design possibilities for broadband optical/acoustical devices.

  1. Spreading of droplet with insoluble surfactant on corrugated topography

    NASA Astrophysics Data System (ADS)

    Li, Chunxi; Pei, Jianjun; Ye, Xuemin

    2014-09-01

    The flow of microscale fluid on a topography surface is a key to further development of MEMS, nanoscience and technology. In the present paper, a theoretical model of the droplet spreading with insoluble surfactant over corrugated topography is established with the lubrication theory, and the evolution equations of film thickness and surfactant concentration in base state and disturbance state are formulated. The droplet dynamics, the nonlinear stability based on nonmodal stability theory, and the effects of topography structure and Marangoni stress are numerically simulated with PDECOL scheme. Results show that the impact of topographical surface is strengthened apparently while the Marangoni stress driven by surfactant concentration is weakened in the mid-late stages of the spreading. The droplet radius on the topography advances faster and the lowest height of liquid/gas interface near the droplet edge reduces remarkably in the intermediate stage compared with those on the flat wall. The quantity of the wavelet similar to the topography increases gradually, with the characteristics of wavelet crest height with time exhibiting a single-hump feature. The spreading stability is enhanced under the disturbance wavenumber of 4, however, is to deteriorate and even to transform into instability when wavenumber increases further. In addition, the reductive Marangoni number, enhancive capillary number, modest Peclet number, the low height of the topography as well as small wavenumber of topography can make contributions to the evident stability of droplet spreading.

  2. Dispersionless Manipulation of Reflected Acoustic Wavefront by Subwavelength Corrugated Surface

    PubMed Central

    Zhu, Yi-Fan; Zou, Xin-Ye; Li, Rui-Qi; Jiang, Xue; Tu, Juan; Liang, Bin; Cheng, Jian-Chun

    2015-01-01

    Free controls of optic/acoustic waves for bending, focusing or steering the energy of wavefronts are highly desirable in many practical scenarios. However, the dispersive nature of the existing metamaterials/metasurfaces for wavefront manipulation necessarily results in limited bandwidth. Here, we propose the concept of dispersionless wavefront manipulation and report a theoretical, numerical and experimental work on the design of a reflective surface capable of controlling the acoustic wavefront arbitrarily without bandwidth limitation. Analytical analysis predicts the possibility to completely eliminate the frequency dependence with a specific gradient surface which can be implemented by designing a subwavelength corrugated surface. Experimental and numerical results, well consistent with the theoretical predictions, have validated the proposed scheme by demonstrating a distinct phenomenon of extraordinary acoustic reflection within an ultra-broad band. For acquiring a deeper insight into the underlying physics, a simple physical model is developed which helps to interpret this extraordinary phenomenon and predict the upper cutoff frequency precisely. Generations of planar focusing and non-diffractive beam have also been exemplified. With the dispersionless wave-steering capability and deep discrete resolution, our designed structure may open new avenue to fully steer classical waves and offer design possibilities for broadband optical/acoustical devices. PMID:26077772

  3. Using Flexible Pipe (poly-pipe) with Surface Irrigation 

    E-print Network

    Peries, Xavier; Enciso, Juan

    2005-10-05

    ? Poly-pipe rolls ? Pump or valve for connection ? Clamps, rubber straps, or duct tape ? Shovel ? PVC connectors (if more than one roll is used) ? Hole puncher with plugs Prior to poly-pipe installation, fields should be leveled. Poly-pipe should.... Advantages of Using Pipes to Deliver Irrigation Water Using pipe systems (rather than earthen ditches) to convey and distribute water to fields has several advantages: ? Increases in on-farm irrigation efficiency, by avoiding water loss due to deep...

  4. Piping stress handbook. Second edition

    SciTech Connect

    Helguero, V.

    1986-01-01

    This abridged volume contains the following: Coefficients of thermal expansion. Allowable stress range for ANSI/ASME Power Piping Code B31.1. Stress intensification and flexibility factors. Pressure and stress ratios. Design criteria for allowable loads, moment, and stresses. Properties of pipe. Weight and dimensions of pipe and components. Pipe support selection and design. Fundamentals of expansion joints. Index.

  5. Experimenting with a "Pipe" Whistle

    ERIC Educational Resources Information Center

    Stafford, Olga

    2012-01-01

    A simple pipe whistle can be made using pieces of PVC pipe. The whistle can be used to measure the resonant frequencies of open or closed pipes. A slightly modified version of the device can be used to also investigate the interesting dependence of the sound frequencies produced on the orifice-to-edge distance. The pipe whistle described here…

  6. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, C.F.; Howard, B.D.

    1994-01-01

    Pipe crawlers, pipe inspection {open_quotes}rabbits{close_quotes} and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks and process vessels for damaged or flawed structural features. This paper describes the design of a flexible, modular ultrasonic pipe inspection apparatus.

  7. Pipe Insulation Economies 

    E-print Network

    Schilling, R. E.

    1986-01-01

    stream_source_info ESL-IE-86-06-97.pdf.txt stream_content_type text/plain stream_size 11050 Content-Encoding ISO-8859-1 stream_name ESL-IE-86-06-97.pdf.txt Content-Type text/plain; charset=ISO-8859-1 PIPE INSULATION... ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram written in IBM basic to simplify the economic insulation thickness for an insulated pipe. Many artic1es have been wr i...

  8. An electrohydrodynamic heat pipe.

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1972-01-01

    A heat pipe of new design, using an electrode structure to orient and guide the dielectric liquid phase flow, is proposed. Analysis indicates that the operation of the electrohydrodynamic heat pipe is in direct analogy to capillary devices, with the polarization force acting in place of capillarity. Advantages of these new heat pipes include greatly reduced liquid friction, electrohydrodynamically enhanced evaporation and condensation heat transfer, and a possible voltage-controlled on/off feature. Preliminary calculations indicate that relatively high performance devices are possible.

  9. Electrohydrodynamic heat pipes.

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1973-01-01

    An electrohydrodynamic heat pipe of radical design is proposed which substitutes polarization electrohydrodynamic force effects for capillarity in collecting, guiding, and pumping a condensate liquid phase. The discussed device is restricted to the use of dielectric liquids as working fluids. Because of the relatively poor thermal transport properties of these liquids, capillary heat pipes using these liquids have not been high performance devices. The employment of the electrohydrodynamic concept should enhance this performance and help fill the performance gap that exists in the temperature range from 250 F to 750 F for 'conventional' capillary heat pipes.

  10. Gas pipe explorer robot

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian (Inventor)

    2004-01-01

    A gas pipe explorer formed of a plurality of connecting elements, and an articulation element between the connected elements. The connected elements include drive capabilities, and the articulation element allows the connected elements to traverse gas pipes of arbitrary shapes and sizes. A sensor may sends the characteristics of the gas pipe, and the communication element may send back those sends characteristics. The communication can be wired, over a tether connecting the device to a remote end. Alternatively, the connection can be wireless, driven by either a generator or a battery.

  11. Effective pipe coating takes care

    SciTech Connect

    Polkinhorne, D.A.

    1980-01-01

    A discussion of the operations involved in the preparation of effective hot-enamel pipe coating covers the storage, drying, and cleaning of the pipe, including the segregation of pipe carried on the deck of ocean-going ships or barges so as to allow weathering to remove salt spray; application of primer coatings; melting and heating of enamel; application of the hot enamel coating; inspection; and storage of coated pipe, and concludes that the effectiveness of a hot-enamel pipe coating is a shared responsibility between the pipeline owner, pipe-coating materials manufacturer, and the pipe-coating contractor.

  12. Improved Thin, Flexible Heat Pipes

    NASA Technical Reports Server (NTRS)

    Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.

    2004-01-01

    Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.

  13. The pipes of pan.

    PubMed

    Chalif, David J

    2004-12-01

    The pipes of pan is the crowning achievement of Pablo Picasso's neoclassical period of the 1920s. This monumental canvas depicts a mythological Mediterranean scene in which two sculpted classical giants stare out, seemingly across the centuries, toward a distant and lost Arcadia. Picasso was influenced by Greco-Roman art during his travels in Italy, and his neoclassical works typically portray massive, immobile, and pensive figures. Pan and his pipes are taken directly from Greek mythological lore by Picasso and placed directly into 20th century art. He frequently turned to various mythological figures throughout his metamorphosing periods. The Pipes of Pan was also influenced by the painter's infatuation with the beautiful American expatriate Sara Murphy, and the finished masterpiece represents a revision of a previously conceived neoclassical work. The Pipes of Pan now hangs in the Musee Picasso in Paris. PMID:15574231

  14. DRAINAGE PIPE DETECTOR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the more frustrating problems confronting farmers and land improvement contractors in the Midwestern United States involves locating buried agricultural drainage pipes. Conventional geophysical methods, particularly ground penetrating radar (GPR), presently being used for environmental and co...

  15. Heat pipe manufacturing study

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1974-01-01

    Heat pipe manufacturing methods are examined with the goal of establishing cost effective procedures that will ultimately result in cheaper more reliable heat pipes. Those methods which are commonly used by all heat pipe manufacturers have been considered, including: (1) envelope and wick cleaning, (2) end closure and welding, (3) mechanical verification, (4) evacuation and charging, (5) working fluid purity, and (6) charge tube pinch off. The study is limited to moderate temperature aluminum and stainless steel heat pipes with ammonia, Freon-21 and methanol working fluids. Review and evaluation of available manufacturers techniques and procedures together with the results of specific manufacturing oriented tests have yielded a set of recommended cost-effective specifications which can be used by all manufacturers.

  16. Heat Pipe Systems

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The heat pipe was developed to alternately cool and heat without using energy or any moving parts. It enables non-rotating spacecraft to maintain a constant temperature when the surface exposed to the Sun is excessively hot and the non Sun-facing side is very cold. Several organizations, such as Tropic-Kool Engineering Corporation, joined NASA in a subsequent program to refine and commercialize the technology. Heat pipes have been installed in fast food restaurants in areas where humid conditions cause materials to deteriorate quickly. Moisture removal was increased by 30 percent in a Clearwater, FL Burger King after heat pipes were installed. Relative humidity and power consumption were also reduced significantly. Similar results were recorded by Taco Bell, which now specifies heat pipe systems in new restaurants in the Southeast.

  17. Miniature pipe crawler tractor

    DOEpatents

    McKay, Mark D. (Idaho Falls, ID); Anderson, Matthew O. (Idaho Falls, ID); Ferrante, Todd A. (Westerville, OH); Willis, W. David (Idaho Falls, ID)

    2000-01-01

    A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.

  18. Silicon Heat Pipe Array

    NASA Technical Reports Server (NTRS)

    Yee, Karl Y.; Ganapathi, Gani B.; Sunada, Eric T.; Bae, Youngsam; Miller, Jennifer R.; Beinsford, Daniel F.

    2013-01-01

    Improved methods of heat dissipation are required for modern, high-power density electronic systems. As increased functionality is progressively compacted into decreasing volumes, this need will be exacerbated. High-performance chip power is predicted to increase monotonically and rapidly with time. Systems utilizing these chips are currently reliant upon decades of old cooling technology. Heat pipes offer a solution to this problem. Heat pipes are passive, self-contained, two-phase heat dissipation devices. Heat conducted into the device through a wick structure converts the working fluid into a vapor, which then releases the heat via condensation after being transported away from the heat source. Heat pipes have high thermal conductivities, are inexpensive, and have been utilized in previous space missions. However, the cylindrical geometry of commercial heat pipes is a poor fit to the planar geometries of microelectronic assemblies, the copper that commercial heat pipes are typically constructed of is a poor CTE (coefficient of thermal expansion) match to the semiconductor die utilized in these assemblies, and the functionality and reliability of heat pipes in general is strongly dependent on the orientation of the assembly with respect to the gravity vector. What is needed is a planar, semiconductor-based heat pipe array that can be used for cooling of generic MCM (multichip module) assemblies that can also function in all orientations. Such a structure would not only have applications in the cooling of space electronics, but would have commercial applications as well (e.g. cooling of microprocessors and high-power laser diodes). This technology is an improvement over existing heat pipe designs due to the finer porosity of the wick, which enhances capillary pumping pressure, resulting in greater effective thermal conductivity and performance in any orientation with respect to the gravity vector. In addition, it is constructed of silicon, and thus is better suited for the cooling of semiconductor devices.

  19. Freezable heat pipe

    DOEpatents

    Ernst, Donald M. (Leola, PA); Sanzi, James L. (Lancaster, PA)

    1981-02-03

    A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.

  20. Simplified pipe gun

    SciTech Connect

    So-dash-barrensen, H.; Nordskov, A.; Sass, B.; Visler, T.

    1987-12-01

    A simplified version of a deuterium pellet gun based on the pipe gun principle is described. The pipe gun is made from a continuous tube of stainless steel and gas is fed in from the muzzle end only. It is indicated that the pellet length is determined by the temperature gradient along the barrel right outside the freezing cell. Velocities of around 1000 m/s with a scatter of +- 2% are obtained with a propellant gas pressure of 40 bar.

  1. Simplified pipe gun

    NASA Astrophysics Data System (ADS)

    Sørensen, H.; Nordskov, A.; Sass, B.; Visler, T.

    1987-12-01

    A simplified version of a deuterium pellet gun based on the pipe gun principle is described. The pipe gun is made from a continuous tube of stainless steel and gas is fed in from the muzzle end only. It is indicated that the pellet length is determined by the temperature gradient along the barrel right outside the freezing cell. Velocities of around 1000 m/s with a scatter of ±2% are obtained with a propellant gas pressure of 40 bar.

  2. On the shape of a hydrostatic meniscus attached to a corrugated plate or wavy cylinder.

    PubMed

    Hill, A I; Pozrikidis, C

    2011-04-15

    The shape of a hydrostatic meniscus attached at a fixed contact angle to a vertical plate or circular cylinder with periodic corrugations is studied by analytical and numerical methods, and the effect of wall irregularities on the shape of the contact line and vertical component of the capillary force is discussed. An asymptotic analysis for a plate with small-amplitude sinusoidal corrugations is carried out to first order with respect to the corrugation amplitude, and a boundary-value problem is formulated and solved by a shooting method to determine the meniscus shape and elevation of the contact line. The meniscus attached to a corrugated plate with rounded corners produced by a Schwarz-Christoffel mapping function for a triangular wave is considered by numerical methods. The Laplace-Young equation determining the meniscus shape is solved in orthogonal curvilinear coordinates generated by conformal mapping using a finite-difference method. The numerical results are successfully compared with the predictions of the perturbation expansion for small amplitudes and discussed with reference to the rise of a meniscus inside a dihedral angle for large amplitudes. A companion asymptotic analysis is presented for a meniscus outside a vertical circular cylinder with small-amplitude sinusoidal corrugations. The analytical predictions are successfully compared with numerical solutions of the Laplace-Young equation for a meniscus outside an elliptical cylinder with aspect ratio near unity, regarded as a deformed circle. PMID:21315363

  3. Heat pipe dynamic behavior

    NASA Technical Reports Server (NTRS)

    Issacci, F.; Roche, G. L.; Klein, D. B.; Catton, I.

    1988-01-01

    The vapor flow in a heat pipe was mathematically modeled and the equations governing the transient behavior of the core were solved numerically. The modeled vapor flow is transient, axisymmetric (or two-dimensional) compressible viscous flow in a closed chamber. The two methods of solution are described. The more promising method failed (a mixed Galerkin finite difference method) whereas a more common finite difference method was successful. Preliminary results are presented showing that multi-dimensional flows need to be treated. A model of the liquid phase of a high temperature heat pipe was developed. The model is intended to be coupled to a vapor phase model for the complete solution of the heat pipe problem. The mathematical equations are formulated consistent with physical processes while allowing a computationally efficient solution. The model simulates time dependent characteristics of concern to the liquid phase including input phase change, output heat fluxes, liquid temperatures, container temperatures, liquid velocities, and liquid pressure. Preliminary results were obtained for two heat pipe startup cases. The heat pipe studied used lithium as the working fluid and an annular wick configuration. Recommendations for implementation based on the results obtained are presented. Experimental studies were initiated using a rectangular heat pipe. Both twin beam laser holography and laser Doppler anemometry were investigated. Preliminary experiments were completed and results are reported.

  4. Numerical Study of Instabilities Induced by Sheet Electron Beam on Corrugated Metal Plate

    NASA Astrophysics Data System (ADS)

    Watanabe, Osamu; Watanabe, Tsuguhiro; Ogura, Kazuo; Tatematsu, Yoshinori; Shima, Yoriko; Imai, Tsuyoshi

    2007-09-01

    It has been confirmed that the normal mode of a surface wave on a corrugated metal plate can be excited by a sheet electron beam. Two types of instabilities are analyzed numerically. One is the Cherenkov instability between the surface normal mode and the slow-space-charge mode of the electron beam. This instability is possibly absolute instability. The oscillation frequency of this instability can be controlled by the amplitude of the corrugation depth. The electron beam energy for this instability is determined by the ratio of the period length and the amplitude of the corrugation. Another is the Smith-Purcell-type instability. This instability is always convective-type instability. The oscillation frequency is higher than that of the above-mentioned Cherenkov instability and is in a broad band. The temporal growth rate of this instability is strongly reduced as the beam energy is reduced.

  5. Demonstration of nonlinear-energy-spread compensation in relativistic electron bunches with corrugated structures

    E-print Network

    Fu, Feichao; Zhu, Pengfei; Zhao, Lingrong; Jiang, Tao; Lu, Chao; Liu, Shengguang; Shi, Libin; Yan, Lixin; Deng, Haixiao; Feng, Chao; Gu, Qiang; Huang, Dazhang; Liu, Bo; Wang, Dong; Wang, Xingtao; Zhang, Meng; Zhao, Zhentang; Stupakov, Gennady; Xiang, Dao; Zhang, Jie

    2015-01-01

    High quality electron beams with flat distributions in both energy and current are critical for many accelerator-based scientific facilities such as free-electron lasers and MeV ultrafast electron diffraction and microscopes. In this Letter we report on using corrugated structures to compensate for the beam nonlinear energy chirp imprinted by the curvature of the radio-frequency field, leading to a significant reduction in beam energy spread. By using a pair of corrugated structures with orthogonal orientations, we show that the quadrupole wake fields which otherwise increase beam emittance can be effectively canceled. This work also extends the applications of corrugated structures to the low beam charge (a few pC) and low beam energy (a few MeV) regime and may have a strong impact in many accelerator-based facilities.

  6. Railscan: A Tool for the Detection and Quantification of Rail Corrugation

    NASA Astrophysics Data System (ADS)

    Gomes, Rui; Batista, Arnaldo; Ortigueira, Manuel; Rato, Raul; Baldeiras, Marco

    Rail corrugation is a phenomenon that leads to a waving in the rails with wavelengths typically between 3 cm and 100 cm and amplitude levels of several microns. The genesis of this waving is complex. Rail corrugation is a recognized problem that leads to excess vibration on the rails and vehicles to a point of reducing their life span and compromising safety. In urban areas excess vibration noise is also a problem. A software tool was developed to analyze accelerometer signals acquired in the boggies of rail vehicles in order to quantify the rail corrugation according to their frequency and amplitude. A wavelet packet methodology was used in this work and compared with the One Third Octave Filter (OTOF) power representations, which is currently used in the industry. It is shown that the former produces better results.

  7. Demonstration of nonlinear-energy-spread compensation in relativistic electron bunches with corrugated structures.

    PubMed

    Fu, Feichao; Wang, Rui; Zhu, Pengfei; Zhao, Lingrong; Jiang, Tao; Lu, Chao; Liu, Shengguang; Shi, Libin; Yan, Lixin; Deng, Haixiao; Feng, Chao; Gu, Qiang; Huang, Dazhang; Liu, Bo; Wang, Dong; Wang, Xingtao; Zhang, Meng; Zhao, Zhentang; Stupakov, Gennady; Xiang, Dao; Zhang, Jie

    2015-03-20

    High quality electron beams with flat distributions in both energy and current are critical for many accelerator-based scientific facilities such as free-electron lasers and MeV ultrafast electron diffraction and microscopes. In this Letter, we report on using corrugated structures to compensate for the beam nonlinear energy chirp imprinted by the curvature of the radio-frequency field, leading to a significant reduction in beam energy spread. By using a pair of corrugated structures with orthogonal orientations, we show that the quadrupole wakefields, which, otherwise, increase beam emittance, can be effectively canceled. This work also extends the applications of corrugated structures to the low beam charge (a few pC) and low beam energy (a few MeV) regime and may have a strong impact in many accelerator-based facilities. PMID:25839281

  8. Graphene on Ru(0001) Moire Corrugation Studied by Scanning Tunneling Microscopy on Au/Graphene/Ru(0001) Heterostructures

    E-print Network

    Ciobanu, Cristian

    Graphene on Ru(0001) Moire Corrugation Studied by Scanning Tunneling Microscopy on Au/Graphene on graphene/Ru(0001) were used to study the corrugation of the moire structure of graphene/Ru(0001 for the graphene/Ru(0001) moire is of structural nature rather than electronic. STM showed a large value

  9. Corrugation-induced metal-semiconductor transition in single-wall carbon nanotubes with a small radius

    NASA Astrophysics Data System (ADS)

    Lu, Hongxia; Wu, Jianbao; Zhang, Weiyi

    2013-07-01

    Armchair single-wall carbon nanotubes (SWCNTs) are theoretically predicted to be metallic in the simple zone-folding scheme and protected from the curvature effects. They are, however, found to be small-gap semiconductors, experimentally. Lacking the genuine band-gap opening mechanism for armchair SWCNTs, the Mott insulator concept was proposed previously for the nominally metallic carbon nanotubes. Using the ab initio local density approximation method, we show, in this paper, that the carbon nanotubes without corrugation are, in fact, not metastable. The corrugated structures are always lower in energy than those without corrugation. The size of corrugation increases rapidly with the nanotubes’ curvature and vanishes for flat graphene. The corrugation breaks the local symmetry between two types of carbon sites, and a true band gap starts to develop once graphene sheets are rolled up into nanotubes.

  10. Graphene-assisted near-field radiative heat transfer between corrugated polar materials

    SciTech Connect

    Liu, X. L.; Zhang, Z. M.

    2014-06-23

    Graphene has attracted great attention in nanoelectronics, optics, and energy harvesting. Here, the near-field radiative heat transfer between graphene-covered corrugated silica is investigated based on the exact scattering theory. It is found that graphene can improve the radiative heat flux between silica gratings by more than one order of magnitude and alleviate the performance sensitivity to lateral shift. The underlying mechanism is mainly attributed to the improved photon tunneling of modes away from phonon resonances. Besides, coating with graphene leads to nonlocal radiative transfer that breaks Derjaguin's proximity approximation and enables corrugated silica to outperform bulk silica in near-field radiation.

  11. The Casimir force on a surface with shallow nanoscale corrugations: Geometry and finite conductivity effects

    E-print Network

    Y. Bao; R. Guérout; J. Lussange; A. Lambrecht; R. A. Cirelli; F. Klemens; W. M. Mansfield; C. S. Pai; H. B. Chan

    2010-09-17

    We measure the Casimir force between a gold sphere and a silicon plate with nanoscale, rectangular corrugations with depth comparable to the separation between the surfaces. In the proximity force approximation (PFA), both the top and bottom surfaces of the corrugations contribute to the force, leading to a distance dependence that is distinct from a flat surface. The measured Casimir force is found to deviate from the PFA by up to 15%, in good agreement with calculations based on scattering theory that includes both geometry effects and the optical properties of the material.

  12. Structural properties of superplastically formed/diffusion-bonded orthogonally corrugated core sandwich plates

    NASA Technical Reports Server (NTRS)

    Ko, W. L.

    1980-01-01

    This paper describes a new superplastically formed/diffusion-bonded (SPF/DB) orthogonally corrugated sandwich structure, and presents formulae and the associated plots for evaluating the effective elastic constants for the core of this new sandwich structure. Comparison of structural properties of this new sandwich structure with the conventional honeycomb core sandwich structure was made under the condition of equal sandwich density. It was found that the SPF/DB orthogonally corrugated sandwich core has higher transverse shear stiffness than the conventional honeycomb sandwich core. However, the former has lower stiffness in the sandwich core thickness direction than the latter.

  13. Corrugated sapphire substrates for organic light-emitting diode light extraction.

    PubMed

    Youn, Wooram; Lee, Jinhyung; Xu, Minfei; Singh, Rajiv; So, Franky

    2015-05-01

    In an organic light-emitting diode (OLED), only about 20-30% of the generated light can be extracted because of the light lost to the thin film guided modes and surface plasmon. Using corrugated high-index-refractive substrates, the thin film guided modes can be effectively out-coupled from the device because of the high index substrate and the loss to the surface plamon is suppressed due to the corrugated structure. With an additional macro lens attached to the substrate to extract the substrate mode, we finally demonstrated a green phosphorescent OLED with an extremely high external quantum efficiency of 63%. PMID:25894577

  14. Structural efficiency studies of corrugated compression panels with curved caps and beaded webs

    NASA Technical Reports Server (NTRS)

    Davis, R. C.; Mills, C. T.; Prabhakaran, R.; Jackson, L. R.

    1984-01-01

    Curved cross-sectional elements are employed in structural concepts for minimum-mass compression panels. Corrugated panel concepts with curved caps and beaded webs are optimized by using a nonlinear mathematical programming procedure and a rigorous buckling analysis. These panel geometries are shown to have superior structural efficiencies compared with known concepts published in the literature. Fabrication of these efficient corrugation concepts became possible by advances made in the art of superplastically forming of metals. Results of the mass optimization studies of the concepts are presented as structural efficiency charts for axial compression.

  15. Elastic constants for superplastically formed/diffusion-bonded corrugated sandwich core

    NASA Technical Reports Server (NTRS)

    Ko, W. L.

    1980-01-01

    Formulas and associated graphs for evaluating the effective elastic constants for a superplastically formed/diffusion bonded (SPF/DB) corrugated sandwich core, are presented. A comparison of structural stiffnesses of the sandwich core and a honeycomb core under conditions of equal sandwich core density was made. The stiffness in the thickness direction of the optimum SPF/DB corrugated core (that is, triangular truss core) is lower than that of the honeycomb core, and that the former has higher transverse shear stiffness than the latter.

  16. Explosive Welding of Pipes

    NASA Astrophysics Data System (ADS)

    Burtseva, Olga

    2007-06-01

    For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe. Model experiments with pipes having radii R = 57 mm confirmed results of the calculations and the possibility in principle to weld pipes by explosion with use of water as filler. Reduction of pipe diameter after dynamic loading and explosive welding was ˜2%.

  17. Remotely operated pipe connector

    DOEpatents

    Josefiak, Leonard J. (Scotia, NY); Cramer, Charles E. (Guilderford, NY)

    1988-01-01

    An apparatus for remotely assembling and disassembling a Graylock type coctor between a pipe and a closure for the pipe includes a base and a receptacle on the base for the closure. The pipe is moved into position vertically above the closure by a suitable positioning device such that the flange on the pipe is immediately adjacent and concentric with the flange on the closure. A moving device then moves two semicircular collars from a position free of the closure to a position such that the interior cam groove of each collar contacts the two flanges. Finally, a tensioning device automatically allows remote tightening and loosening of a nut and bolt assembly on each side of the collar to cause a seal ring located between the flanges to be compressed and to seal the closure. Release of the pipe and the connector is accomplished in the reverse order. Preferably, the nut and bolt assembly includes an elongate shaft portion on which a removable sleeve is located.

  18. 49 CFR 230.62 - Dry pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 4 2011-10-01 2011-10-01 false Dry pipe. 230.62 Section 230.62 Transportation...MAINTENANCE STANDARDS Boilers and Appurtenances Steam Pipes § 230.62 Dry pipe. Dry pipes subject to pressure shall be...

  19. 49 CFR 230.62 - Dry pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 4 2010-10-01 2010-10-01 false Dry pipe. 230.62 Section 230.62 Transportation...MAINTENANCE STANDARDS Boilers and Appurtenances Steam Pipes § 230.62 Dry pipe. Dry pipes subject to pressure shall be...

  20. Apparatus for moving a pipe inspection probe through piping

    DOEpatents

    Zollinger, W.T.; Appel, D.K.; Lewis, G.W.

    1995-07-18

    A method and apparatus are disclosed for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher. 8 figs.

  1. Heat pipes and use of heat pipes in furnace exhaust

    DOEpatents

    Polcyn, Adam D. (Pittsburgh, PA)

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  2. Apparatus for moving a pipe inspection probe through piping

    DOEpatents

    Zollinger, W. Thor (Martinez, GA); Appel, D. Keith (Aiken, SC); Lewis, Gregory W. (North Augusta, SC)

    1995-01-01

    A method and apparatus for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher.

  3. Apparatus for inspecting piping

    DOEpatents

    Zollingger, W. Thor (Martinez, GA); Appel, D. Keith (Aiken, SC); Park, Larry R. (Raleigh, NC)

    1995-01-01

    An inspection rabbit for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON.RTM.). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system.

  4. Apparatus for inspecting piping

    DOEpatents

    Zollingger, W.T.; Appel, D.K.; Park, L.R.

    1995-03-21

    An inspection rabbit is described for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON{trademark}). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system. 6 figures.

  5. Heat-pipe Earth.

    PubMed

    Moore, William B; Webb, A Alexander G

    2013-09-26

    The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics. PMID:24067709

  6. Composite drill pipe

    DOEpatents

    Leslie, James C. (Fountain Valley, CA); Leslie, II, James C. (Mission Viejo, CA); Heard, James (Huntington Beach, CA); Truong, Liem (Anaheim, CA), Josephson; Marvin (Huntington Beach, CA), Neubert; 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.

  7. Heat pipe array heat exchanger

    DOEpatents

    Reimann, Robert C. (Lafayette, NY)

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  8. Pipe Flow System Holly Guest

    E-print Network

    Clement, Prabhakar

    of a given pipe system involving two reservoirs and to make recommendations based on the outputs on how to improve the design. · Inputs include: · Head of each reservoir · Head of the pump · Pipe Diameter using

  9. Superfluid Helium Heat Pipe

    NASA Astrophysics Data System (ADS)

    Gully, P.

    This paper reports on the development and the thermal tests of three superfluid helium heat pipes. Two of them are designed to provide a large transport capacity (4 mW at 1.7 K). They feature a copper braid located inside a 6 mm outer diameter stainless tube fitted with copper ends for mechanical anchoring. The other heat pipe has no copper braid and is designed to get much smaller heat transport capacity (0.5 mW) and to explore lower temperature (0.7 - 1 K). The copper braid and the tube wall is the support of the Rollin superfluid helium film in which the heat is transferred. The low filling pressure makes the technology very simple with the possibility to easily bend the tube. We present the design and discuss the thermal performance of the heat pipes tested in the 0.7 to 2.0 K temperature range. The long heat pipe (1.2 m with copper braid) and the short one (0.25 m with copper braid) have similar thermal performance in the range 0.7 - 2.0 K. At 1.7 K the long heat pipe, 120 g in weight, reaches a heat transfer capacity of 6.2 mW and a thermal conductance of 600 mW/K for 4 mW transferred power. Due to the pressure drop of the vapor flow and Kapitza thermal resistance, the conductance of the third heat pipe dramatically decreases when the temperature decreases. A 3.8 mW/K is obtained at 0.7 K for 0.5 mW transferred power.

  10. Heat transfer in pipes

    NASA Technical Reports Server (NTRS)

    Burbach, T.

    1985-01-01

    The heat transfer from hot water to a cold copper pipe in laminar and turbulent flow condition is determined. The mean flow through velocity in the pipe, relative test length and initial temperature in the vessel were varied extensively during tests. Measurements confirm Nusselt's theory for large test lengths in laminar range. A new equation is derived for heat transfer for large starting lengths which agrees satisfactorily with measurements for large starting lengths. Test results are compared with the new Prandtl equation for heat transfer and correlated well. Test material for 200- and to 400-diameter test length is represented at four different vessel temperatures.

  11. Pipe Drafting with CAD. Teacher Edition.

    ERIC Educational Resources Information Center

    Smithson, Buddy

    This teacher's guide contains nine units of instruction for a course on computer-assisted pipe drafting. The course covers the following topics: introduction to pipe drafting with CAD (computer-assisted design); flow diagrams; pipe and pipe components; valves; piping plans and elevations; isometrics; equipment fabrication drawings; piping design…

  12. Loop Heat Pipe for Electronics

    E-print Network

    Lee, Ho Sung

    Loop Heat Pipe for Electronics Dr. HoSung Lee April 15, 2015 #12;Fujitsu Laboratories Ltd. Figure 1: Configuration of a loop heat pipe Figure 2: New thermal management concept for a smartphone equipped with a loop heat pipe Figure 4: Etched pattern of the evaporator section in an inner layer sheet (The evaporator

  13. Defect characterization in pipe-to-pipe welds in large diameter stainless steel piping

    SciTech Connect

    Rawl, D.E. Jr.; West, S.L.; Wheeler, D.A.; Louthan, M.R. Jr.

    1990-01-01

    Metallurgical evaluation of pipe-to-pipe welds in large-diameter, Type 304 stainless steel piping used to construct the moderator/coolant water systems for Savannah River Site reactors has demonstrated that small weld defects found in this 1950-vintage system do not compromise the integrity of the system. The weld defects were too small for detection by the pre-service standard radiographic inspection, but were found through systematic ultrasonic testing (UT) and penetrant testing (PT) evaluations of piping that had been removed during upgrades to the piping system. The defects include lack of weld penetration, slag inclusions, and other weld metal discontinuities. These discontinuities typically did not propagate during more than 35 years of service. The defects examined were too small and isolated to degrade the mechanical properties of the pipe-to-pipe weldments and therefore did not compromise the integrity of the piping system. 14 refs., 7 figs.

  14. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  15. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  16. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  17. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  18. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  19. Scattering of xenon from Ni,,111...: Collision-induced corrugation and energy transfer dynamics

    E-print Network

    Scattering of xenon from Ni,,111...: Collision-induced corrugation and energy transfer dynamics in which a beam of xenon atoms collides with a clean Ni 111 surface, and the speed and angular is independent of initial and final scattering angles. This result is attributed to multiple xenon

  20. The dynamic response of clamped rectangular Y-frame and corrugated core sandwich plates

    E-print Network

    Fleck, Norman A.

    velocities by inertial stabilization of the webs while plastic shock wave effects dominate the response identical face-sheets and either Y-frame or corrugated cores. The resistance to shock loading is quantified strains lead to failure of the front face sheets of the sandwich plates at lower values of projectile

  1. Convective heat transfer and pressure drop in V-corrugated channel with different phase shifts

    NASA Astrophysics Data System (ADS)

    Sakr, Mohamed

    2015-01-01

    New energy system development and energy conservation require high performance heat exchanger, so the researchers are seeking to find new methods to enhance heat transfer mechanism in heat exchangers. The objectives of this study are investigating heat transfer performance and flow development in V-corrugated channels, numerical simulations were carried out for uniform wall heat flux equal 290 W/m2 using air as a working fluid, Reynolds number varies from 500 to 2,000, phase shifts, 0° < Ø < 180°, and channel heights (S = 12.5, 15.0, 17.5 and 20 mm). Governing equations of flow and energy were solved numerically by using finite volume method. The numerical results indicated that, wavy (V-corrugated) channels have a significant impact on heat transfer enhancement with increase in pressure drop though channel due to breaking and destabilizing in the thermal boundary layer are occurred as fluid flowing through the corrugated surfaces and the effect of corrugated phase shift on the heat transfer and fluid flow is more significant in narrow channel, the goodness factor (j/f) was increased with increasing channel phase shift, the best performance was noticed on phase shift, Ø = 180° and channel height, S = 12.5 mm.

  2. The manufacture of corrugated copper tubes with a Nb/sub 3/Sn layer

    SciTech Connect

    Meshchanov, G.I.; Peshkov, I.B.; Savalo, G.G.

    1985-03-01

    Based on prior experience gained with superconducting materials, further research work was jointly carried out by our organizations. The purpose of this effort was the establishment of a production process for the manufacture of corrugated, high-purity copper tubes incorporating the thickest possible layers of superconducting Nb/sub 3/Sn. The goal of the production process was to develop a corrugated, bendable superconductor as the core of a cryogenic envelope capable of withstanding reeling and unreeling on reels with barrel diameters up to 3 m, without damaging the brittle Nb/sub 3/Sn layer. The manufacturing process is described in detail. The latest results show a superconductor with a critical temperature of 15.5 K, having a 10 micrometer layer of pure Nb/sub 3/Sn. While not completely homogeneous, the sample is capable of carrying currents up to 125 - 140 A on a 10 mm sample width and in a magnetic field of 5 T. The corrugated tube acts at the same time as a selfcompensating helium circuit and as the copperstabilized current-carrying superconductor of a three-phase cable in a flexible cryogenic envelope. The envelope consists of four concentric corrugated tubes with an intermediate nitrogen shield. The resulting losses into the helium circuit are less than 0.2 Wm/sup -1/. The experiments have been conducted, until now, on tube lengths up to 40 m. All steps were carried out on conventional, commercially available equipment.

  3. Negative linear classical magnetoresistance in a corrugated two-dimensional electron gas N. M. Sotomayor*

    E-print Network

    Gusev, Guennady

    to non-Markovian memory effects originated by specific return processes in backscattering of electronsNegative linear classical magnetoresistance in a corrugated two-dimensional electron gas N. M) was measured in a GaAs/AlxGa1-xAs two-dimensional electron system with nonplanar topography, caused by random

  4. Conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    DOEpatents

    Fischer, William H. (Pittsburgh, PA); Yoon, Kue H. (Pittsburgh, PA)

    1984-04-10

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed perpendicular to the direction of travel of the inner conductor/insulating support assembly.

  5. Method for producing ultrafine-grained materials using repetitive corrugation and straightening

    DOEpatents

    Zhu, Yuntian T. (Los Alamos, NM); Lowe, Terry C. (Santa Fe, NM); Jiang, Honggang (Los Alamos, NM); Huang, Jianyu (Los Alamos, NM)

    2001-01-01

    A method of refining the grain structure and improving the hardness and strength properties of a metal or metal alloy workpiece is disclosed. The workpiece is subjected to forces that corrugate and then straighten the workpiece. These steps are repeated until an ultrafine-grained product having improved hardness and strength is produced.

  6. Relative permeability for two-phase flow through corrugated tubes as model porous media

    E-print Network

    Feng, James J.

    Relative permeability for two-phase flow through corrugated tubes as model porous media Majid, University of British Columbia, Vancouver, BC V6T 1Z3, Canada b NRC Institute for Fuel Cell Innovation, 4250 permeability depends not only on saturation, but also on the capillary number, viscosity ratio, wettability

  7. Dynamic Stability of Crack Fronts: Out-Of-Plane Corrugations Mokhtar Adda-Bedia,1

    E-print Network

    Adda-Bedia, Mokhtar

    Dynamic Stability of Crack Fronts: Out-Of-Plane Corrugations Mokhtar Adda-Bedia,1 Rodrigo E. Arias) The dynamics and stability of brittle cracks are not yet fully understood. Here we use the Willis- Movchan 3D of planar crack fronts in the framework of linear elastic fracture mechanics. We discuss a minimal scenario

  8. Acme jumper pipe

    SciTech Connect

    Medved, P.; Thomas, H.

    1995-09-01

    Acme Steel had operated the larry car with an attached jumper pipe since 1977. Acme had been able to meet the State Implementation Plan. With the advent of the Clean Air Act, Acme did not feel it could meet these new standards without some modifications to the jumper pipe system. Several drop sleeve modifications and numerous boot seal materials and configurations were tested that resulted in limited success in improving the boot seal life. After these modifications, Acme`s testing revealed it could meet the Clean Air Act standards, but it would be cost prohibitive to continue to operate in this manner. Following extensive investigation, Acme decided to install an off-car jumper pipe system which uses a traveling U-tube for connecting to the assist oven through an additional hole in each oven roof. Temperature related failures of drop sleeve seals were eliminated. The off-car jumper pipe is a more efficient gas connection to the assist oven and enables Acme to meet the Clean Air Act charging requirements in a cost effective manner.

  9. Explosive Welding of Pipes

    NASA Astrophysics Data System (ADS)

    Drennov, Oleg; Drennov, Andrey; Burtseva, Olga

    2013-06-01

    For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. Explosive welding of cylindrical surfaces is performed by launching of welded layer along longitudinal axis of construction. During this procedure, it is required to provide reliable resistance against radial convergent strains. The traditional method is application of fillers of pipe cavity, which are dense cylindrical objects having special designs. However, when connecting pipes consecutively in pipelines by explosive welding, removal of the fillers becomes difficult and sometimes impossible. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe.

  10. Drill pipe protector development

    SciTech Connect

    Thomerson, C.; Kenne, R.; Wemple, R.P.

    1996-03-01

    The Geothermal Drilling Organization (GDO), formed in the early 1980s by the geothermal industry and the U.S. Department of Energy (DOE) Geothermal Division, sponsors specific development projects to advance the technologies used in geothermal exploration, drilling, and production phases. Individual GDO member companies can choose to participate in specific projects that are most beneficial to their industry segment. Sandia National Laboratories is the technical interface and contracting office for the DOE in these projects. Typical projects sponsored in the past have included a high temperature borehole televiewer, drill bits, muds/polymers, rotary head seals, and this project for drill pipe protectors. This report documents the development work of Regal International for high temperature geothermal pipe protectors.

  11. Heat Pipes For Alyeska

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The heat pipes job is to keep the arctic ground frozen. The permafrost soil alternately freezes and thaws with seasonal temperature changes causing surface dislocations and problems for the builders. In winter, a phenomenon called frost-heaving uplifts the soil. It is something like the creation of highway potholes by the freezing of rainwater below the roadbed, but frost-heaving exerts a far greater force. Thawing of the frost in the summer causes the soil to settle unevenly. Therefore it is necessary to keep the soil in a continually frozen state so the pipeline won't rupture. To solve this problem, McDonnell Douglas Corp. applied heat pipe principles in the design of the vertical supports that hold up the pipeline.

  12. Heat Pipe Systems

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Solar Fundamentals, Inc.'s hot water system employs space-derived heat pipe technology. It is used by a meat packing plant to heat water for cleaning processing machinery. Unit is complete system with water heater, hot water storage, electrical controls and auxiliary components. Other than fans and a circulating pump, there are no moving parts. System's unique design eliminates problems of balancing, leaking, corroding, and freezing.

  13. Pipe inspection using the pipe crawler. Innovative technology summary report

    SciTech Connect

    1999-05-01

    The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.

  14. Heat pipe technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The annual supplement on heat pipe technology for 1971 is presented. The document contains 101 references with abstracts and 47 patents. The subjects discussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design, development, and fabrication of heat pipes, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

  15. Particle trap to sheath contact for a gas-insulated transmission line having a corrugated outer conductor

    DOEpatents

    Fischer, William H. (Pittsburgh, PA); Cookson, Alan H. (Pittsburgh, PA); Yoon, Kue H. (Pittsburgh, PA)

    1984-04-10

    A particle trap to outer elongated conductor or sheath contact for gas-insulated transmission lines. The particle trap to outer sheath contact of the invention is applicable to gas-insulated transmission lines having either corrugated or non-corrugated outer sheaths. The contact of the invention includes an electrical contact disposed on a lever arm which in turn is rotatably disposed on the particle trap and biased in a direction to maintain contact between the electrical contact and the outer sheath.

  16. Experimenting with a ``Pipe'' Whistle

    NASA Astrophysics Data System (ADS)

    Stafford, Olga

    2012-04-01

    A simple pipe whistle can be made using pieces of PVC pipe. The whistle can be used to measure the resonant frequencies of open or closed pipes. A slightly modified version of the device can be used to also investigate the interesting dependence of the sound frequencies produced on the orifice-to-edge distance. The pipe whistle described here allows students in a physics of music or introductory physics course to study an example of an "edge tone" device that produces discrete sound frequencies. From their textbooks, students likely know about standing waves produced by pipes or strings, as well as the resonant frequencies for open and closed pipes. To go a bit further, they can also learn how the frequency of the sound wave depends on the orifice-to-edge distance of the wind instrument.

  17. Lamb wave band gaps in one-dimensional radial phononic crystal plates with periodic double-sided corrugations

    NASA Astrophysics Data System (ADS)

    Li, Yinggang; Chen, Tianning; Wang, Xiaopeng; Li, Suobin

    2015-11-01

    In this paper, we present the theoretical investigation of Lamb wave propagation in one-dimensional radial phononic crystal (RPC) plates with periodic double-sided corrugations. The dispersion relations, the power transmission spectra, and the displacement fields of the eigenmodes are studied by using the finite element method based on two-dimensional axial symmetry models in cylindrical coordinates. Numerical results show that the proposed RPC plates with periodic double-sided corrugations can yield several band gaps with a variable bandwidth for Lamb waves. The formation mechanism of band gaps in the double-sided RPC plates is attributed to the coupling between the Lamb modes and the in-phase and out-phases resonant eigenmodes of the double-sided corrugations. We investigate the evolution of band gaps in the double-sided RPC plates with the corrugation heights on both sides arranged from an asymmetrical distribution to a symmetrical distribution gradually. Significantly, with the introduction of symmetric double-sided corrugations, the antisymmetric Lamb mode is suppressed by the in-phase resonant eigenmodes of the double-sided corrugations, resulting in the disappearance of the lowest band gap. Furthermore, the effects of the geometrical parameters on the band gaps are further explored numerically.

  18. Enhanced response and sensitivity of self-corrugated graphene sensors with anisotropic charge distribution

    NASA Astrophysics Data System (ADS)

    Yol Jeong, Seung; Jeong, Sooyeon; Won Lee, Sang; Tae Kim, Sung; Kim, Daeho; Jin Jeong, Hee; Tark Han, Joong; Baeg, Kang-Jun; Yang, Sunhye; Seok Jeong, Mun; Lee, Geon-Woong

    2015-06-01

    We introduce a high-performance molecular sensor using self-corrugated chemically modified graphene as a three dimensional (3D) structure that indicates anisotropic charge distribution. This is capable of room-temperature operation, and, in particular, exhibiting high sensitivity and reversible fast response with equilibrium region. The morphology consists of periodic, “cratered” arrays that can be formed by condensation and evaporation of graphene oxide (GO) solution on interdigitated electrodes. Subsequent hydrazine reduction, the corrugated edge area of the graphene layers have a high electric potential compared with flat graphene films. This local accumulation of electrons interacts with a large number of gas molecules. The sensitivity of 3D-graphene sensors significantly increases in the atmosphere of NO2 gas. The intriguing structures have several advantages for straightforward fabrication on patterned substrates, high-performance graphene sensors without post-annealing process.

  19. Enhanced response and sensitivity of self-corrugated graphene sensors with anisotropic charge distribution.

    PubMed

    Jeong, Seung Yol; Jeong, Sooyeon; Lee, Sang Won; Kim, Sung Tae; Kim, Daeho; Jeong, Hee Jin; Han, Joong Tark; Baeg, Kang-Jun; Yang, Sunhye; Jeong, Mun Seok; Lee, Geon-Woong

    2015-01-01

    We introduce a high-performance molecular sensor using self-corrugated chemically modified graphene as a three dimensional (3D) structure that indicates anisotropic charge distribution. This is capable of room-temperature operation, and, in particular, exhibiting high sensitivity and reversible fast response with equilibrium region. The morphology consists of periodic, "cratered" arrays that can be formed by condensation and evaporation of graphene oxide (GO) solution on interdigitated electrodes. Subsequent hydrazine reduction, the corrugated edge area of the graphene layers have a high electric potential compared with flat graphene films. This local accumulation of electrons interacts with a large number of gas molecules. The sensitivity of 3D-graphene sensors significantly increases in the atmosphere of NO2 gas. The intriguing structures have several advantages for straightforward fabrication on patterned substrates, high-performance graphene sensors without post-annealing process. PMID:26053892

  20. Structural testing of corrugated asbestos-cement roof panels at the Hanford Facilities, Richland, Washington

    SciTech Connect

    Moustafa, S.E.; Rodehaver, S.M.; Frier, W.A.

    1993-10-01

    This report describes a roof testing program that was carried out at the 105KE/KW Spent Fuel Storage Basins and their surrounding facilities at the Hanford Site in Richland, Washington. The roof panels were constructed in the mid 1950`s of corrugated asbestos-cement (A/C), which showed common signs of aging. Based on the construction specifications, the panels capacity to meet current design standards was questioned. Both laboratory and in-situ load testing of the corrugated A/C panels was conducted. The objective of the complete test program was to determine the structural integrity of the existing A/C roof panels installed in the 105KE and 105KW facilities. The data from these tests indicated that the roofs are capable of resisting the design loads and are considered safe. A second phase test to address the roof resistance to personnel and roof removal/roofing system installation equipment was recommended and is underway.

  1. Spoof localized surface plasmons in corrugated ring structures excited by microstrip line.

    PubMed

    Yang, Bao Jia; Zhou, Yong Jin; Xiao, Qian Xun

    2015-08-10

    We have investigated the fundamental and high-order spoof localized surface plasmons (LSPs) modes in the proposed corrugated ring resonator printed on a thin dielectric substrate with or without ground plane. An efficient and ease-of-integration method to excite spoof LSPs in the textured ring resonator has been adopted to suppress unwanted high-order modes and enhance fundamental modes. A multi-band-pass filter has been proposed and numerically demonstrated. Experimental results at the microwave frequencies verify the high performances of the corrugated ring resonator and the filter, showing great agreements with the simulation results. We have also shown that the fabricated device is sensitive to the variation of the refraction index of materials under test, even when the material is as thin as paper. PMID:26367991

  2. Enhanced response and sensitivity of self-corrugated graphene sensors with anisotropic charge distribution

    PubMed Central

    Yol Jeong, Seung; Jeong, Sooyeon; Won Lee, Sang; Tae Kim, Sung; Kim, Daeho; Jin Jeong, Hee; Tark Han, Joong; Baeg, Kang-Jun; Yang, Sunhye; Seok Jeong, Mun; Lee, Geon-Woong

    2015-01-01

    We introduce a high-performance molecular sensor using self-corrugated chemically modified graphene as a three dimensional (3D) structure that indicates anisotropic charge distribution. This is capable of room-temperature operation, and, in particular, exhibiting high sensitivity and reversible fast response with equilibrium region. The morphology consists of periodic, “cratered” arrays that can be formed by condensation and evaporation of graphene oxide (GO) solution on interdigitated electrodes. Subsequent hydrazine reduction, the corrugated edge area of the graphene layers have a high electric potential compared with flat graphene films. This local accumulation of electrons interacts with a large number of gas molecules. The sensitivity of 3D-graphene sensors significantly increases in the atmosphere of NO2 gas. The intriguing structures have several advantages for straightforward fabrication on patterned substrates, high-performance graphene sensors without post-annealing process. PMID:26053892

  3. Cryogenic Heat Pipe Experiment (CRYOHP)

    NASA Technical Reports Server (NTRS)

    Mcintosh, Roy

    1992-01-01

    The objective of the CRYOHP experiment is to conduct a shuttle experiment that demonstrates the reliable operation of two oxygen heat pipes in microgravity. The experiment will perform the following tasks: (1) demonstrate startup of the pipes from the supercritical state; (2) measure the heat transport capacity of the pipes; (3) measure evaporator and condenser film coefficients; and (4) work shuttle safety issues. The approach for the experiment is as follows: (1) fly two axially grooved oxygen heat pipes attached to mechanical stirling cycle tactical coolers; (2) integrate experiment in hitch-hiker canister; and (3) fly on shuttle and control from ground.

  4. 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.

  5. MTR BUILDING, TRA603. EAST SIDE. CAMERA FACING WEST. CORRUGATED IRON ...

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

    MTR BUILDING, TRA-603. EAST SIDE. CAMERA FACING WEST. CORRUGATED IRON BUILDING MARKED WITH "X" IS TRA-651. TRA-626, TO ITS RIGHT, HOUSED COMPRESSOR EQUIPMENT FOR THE AIRCRAFT NUCLEAR PROPULSION PROGRAM. LATER, IT WAS USED FOR STORAGE. INL NEGATIVE NO. HD46-42-4. Mike Crane, Photographer, April 2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  6. Effects of Antimicrobial Peptide Revealed by Simulations: Translocation, Pore Formation, Membrane Corrugation and Euler Buckling

    PubMed Central

    Chen, Licui; Jia, Nana; Gao, Lianghui; Fang, Weihai; Golubovic, Leonardo

    2013-01-01

    We explore the effects of the peripheral and transmembrane antimicrobial peptides on the lipid bilayer membrane by using the coarse grained Dissipative Particle Dynamics simulations. We study peptide/lipid membrane complexes by considering peptides with various structure, hydrophobicity and peptide/lipid interaction strength. The role of lipid/water interaction is also discussed. We discuss a rich variety of membrane morphological changes induced by peptides, such as pore formation, membrane corrugation and Euler buckling. PMID:23579956

  7. Ohmic losses in coaxial resonators with longitudinal inner-outer corrugation

    SciTech Connect

    Shenyong Hou, A.; Yangtze Normal University, Chongqing 408001 ; Sheng Yu, B.; Hongfu Li, C.; Qixiang Zhao, D.; Xiang Li, E.; Queen Mary University of London, London E1 4NS

    2013-05-15

    In this paper, a coaxial resonator with longitudinal inner-outer corrugation is introduced. Its eigen-equation and expression of ohmic losses are derived. Ohmic losses in the cavity are investigated. Results show that ohmic losses in the outer and inner conductors share a similar variation trend, while the former is larger than the later. What's more, changes of the inner and outer slot depth and width induce different variations of ohmic losses on the surface of the inner and outer conductors.

  8. Corrugated Waveguide and Directional Coupler for CW 250-GHz Gyrotron DNP Experiments

    PubMed Central

    Woskov, Paul P.; Bajaj, Vikram S.; Hornstein, Melissa K.; Temkin, Richard J.; Griffin, Robert G.

    2007-01-01

    A 250-GHz corrugated transmission line with a directional coupler for forward and backward power monitoring has been constructed and tested for use with a 25-W continuous-wave gyrotron for dynamic nuclear polarization (DNP) experiments. The main corrugated line (22-mm internal diameter, 2.4-m long) connects the gyrotron output to the DNP probe input. The directional coupler, inserted approximately midway, is a four-port crossed waveguide beamsplitter design. Two beamsplitters, a quartz plate and ten-wire array, were tested with output coupling of 2.5% (?16 dB) at 250.6 GHz and 1.6% (?18 dB), respectively. A pair of mirrors in the DNP probe transferred the gyrotron beam from the 22-mm waveguide to an 8-mm helically corrugated waveguide for transmission through the final 0.58-m distance inside the NMR magnet to the sample. The transmission-line components were all cold tested with a 248 ± 4-GHz radiometer. A total insertion loss of 0.8 dB was achieved for HE11 -mode propagation from the gyrotron to the sample with only 1% insertion loss for the 22-mm-diameter waveguide. A clean Gaussian gyrotron beam at the waveguide output and reliable forward power monitoring were achieved for many hours of continuous operation. PMID:17901907

  9. The Parker Instability in 3-D: Corrugations and Superclouds Along the Carina-Sagittarius Arm

    E-print Network

    Jose Franco; Jongsoo Kim; Emilio J. Alfaro; Seung Soo Hong

    2001-11-21

    Here we present three-dimensional MHD models for the Parker instability in a thick magnetized disk, including the presence of a spiral arm. The $B$-field is assumed parallel to the arm, and the model results are applied to the optical segment of the Carina-Sagittarius arm. The characteristic features of the undular and interchange modes are clearly apparent in the simulations. The undular mode creates large gas concentrations distributed along the arm. This results in a clear arm/inter-arm difference: the instability triggers the formation of large interstellar clouds inside the arms, but generates only small structures with slight density enhancements in the inter-arm regions. The resulting clouds are distributed in an antisymmetric way with respect to the midplane, creating an azimuthal corrugation along the arm. For conditions similar to those of the optical segment of the Carina-Sagittarius arm, it has a wavelength of about 2.4 kpc. This structuring can explain the origin of both HI superclouds and the azimuthal corrugations in spiral arms. The wavelength matches the corrugation length derived with the young stellar groups located in the optical segment of the Carina-Sagittarius arm. Keywords: Galaxy: kinematics and dynamics -- Galaxy: structure -- Instabilities -- ISM: clouds -- ISM: magnetic fields -- ISM: structure -- MHD

  10. Experimental investigation on the dynamic response of clamped corrugated sandwich plates subjected to underwater impulsive loadings

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Zhang, Wei; Li, Dacheng; Hypervelocity Impact Research Center Team

    2015-06-01

    Corrugated sandwich plates are widely used in marine industry because such plates have high strength-to-weight ratios and blast resistance. The laboratory-scaled fluid-structure interaction experiments are performed to demonstrate the shock resistance of solid monolithic plates and corrugated sandwich plates by quantifying the permanent transverse deflection at mid-span of the plates as a function of impulsive loadings per areal mass. Sandwich structures with 6mm-thick and 10mm-thick 3003 aluminum corrugated core and 5A06 face sheets are compared with the 5A06 solid monolithic plates in this paper. The dynamic deformation of plates are captured with the the 3D digital speckle correlation method (DIC). The results affirm that sandwich structures show a 30% reduction in the maximum plate deflection compare with a monolithic plate of identical mass per unit area, and the peak value of deflection effectively reduced by increasing the thickness core. The failure modes of sandwich plates consists of core crushing, imprinting, stretch tearing of face sheets, bending and permanent deformation of entire structure with the increasing impulsive loads, and the failure mechanisms are analyzed with the postmortem panels and dynamic deflection history captured by cameras. National Natural Science Foundation of China (NO.: 11372088).

  11. Making angle-resolved photoemission measurements on corrugated monolayer crystals: Suspended exfoliated single-crystal graphene

    NASA Astrophysics Data System (ADS)

    Knox, Kevin R.; Locatelli, Andrea; Yilmaz, Mehmet B.; Cvetko, Dean; Mente?, Tevfik Onur; Niño, Miguel Ángel; Kim, Philip; Morgante, Alberto; Osgood, Richard M., Jr.

    2011-09-01

    Free-standing exfoliated monolayer graphene is an ultrathin flexible membrane, which exhibits out-of-plane deformation or corrugation. In this paper, a technique is described to measure the band structure of such free-standing graphene by angle-resolved photoemission. Our results show that photoelectron coherence is limited by the crystal corrugation. However, by combining surface morphology measurements of the graphene roughness with angle-resolved photoemission, energy-dependent quasiparticle lifetime and band-structure measurements can be extracted. Our measurements rely on our development of an analytical formulation for relating the crystal corrugation to the photoemission linewidth. Our angle-resolved photoemission spectroscopy measurements show that, despite significant deviation from planarity of the crystal, the electronic structure of exfoliated suspended graphene is nearly that of ideal, undoped graphene; we measure the Dirac point to be within 25 meV of EF. Further, we show that suspended graphene behaves as a marginal Fermi liquid, with a quasiparticle lifetime that scales as (E-EF)-1; comparison with other graphene and graphite data is discussed.

  12. Method of Green's function of nonlinear vibration of corrugated shallow shells

    NASA Astrophysics Data System (ADS)

    Yuan, Hong

    2008-06-01

    Based on the dynamic equations of nonlinear large deflection of axisymmetric shallow shells of revolution, the nonlinear free vibration and forced vibration of a corrugated shallow shell under concentrated load acting at the center have been investigated. The nonlinear partial differential equations of shallow shell were reduced to the nonlinear integral-differential equations by using the method of Green’s function. To solve the integral-differential equations, the expansion method was used to obtain Green’s function. Then the integral-differential equations were reduced to the form with a degenerate core by expanding Green’s function as a series of characteristic function. Therefore, the integral-differential equations became nonlinear ordinary differential equations with regard to time. The amplitude-frequency relation, with respect to the natural frequency of the lowest order and the amplitude-frequency response under harmonic force, were obtained by considering single mode vibration. As a numerical example, nonlinear free and forced vibration phenomena of shallow spherical shells with sinusoidal corrugation were studied. The obtained solutions are available for reference to the design of corrugated shells.

  13. Flow Regimes of Air-Water Counterflow Through Cross Corrugated Parallel Plates

    SciTech Connect

    de Almeida, V.F.

    2000-06-07

    Heretofore unknown flow regimes of air-water counterflow through a pair of transparent vertical parallel cross corrugated plates were observed via high-speed video. Air flows upward driven by pressure gradient and water, downward driven by gravity. The crimp geometry of the corrugations was drawn from typical corrugated sheets used as filling material in modern structured packed towers. Four regimes were featured, namely, rivulet, bicontinuous, flooding fronts, and flooding waves. It is conceivable that the regimes observed might constitute the basis for understanding how gas and liquid phases contend for available space in the interstices of structured packings in packed towers. Flow regime transitions were expressed in terms of liquid load (liquid superficial velocity) and gas flow factor parameters commonly used in pressure drop and capacity curves. We have carefully examined the range of parameters equivalent to the ill-understood high-liquid-flow operation in packed towers. More importantly, our findings should prove valuable in validating improved first-principles modeling of gas-liquid flows in these industrially important devices.

  14. Fabrication and evaluation of superplastically formed/weld-brazed corrugated compression panels with beaded webs

    NASA Technical Reports Server (NTRS)

    Royster, D. M.; Davis, R. C.; Shinn, J. M., Jr.; Bales, T. T.; Wiant, H. R.

    1985-01-01

    A study was made to investigate the feasibility of superplastically forming corrugated panels with beaded webs and to demonstrate the structural integrity of these panels by testing. The test panels in the study consist of superplastically formed titanium alloy Ti-6Al-4V half-hat elements that are joined by weld-brazing to titanium alloy Ti-6Al-4V caps to form either single-corrugation compression panels or multiple-corrugation compression panels. Stretching and subsequent thinning of the titanium sheet during superplastic forming is reduced by approximately 35 percent with a shallow half-hat die concept instead of a deep die concept and results in a more uniform thickness across the beaded webs. The complete panels are tested in end compression at room temperature and the results compared with analysis. The heavily loaded panels failed at loads approaching the yield strength of the titanium material. At maximum load, the caps wrinkled locally accompanied with separation of the weld-braze joint in the wrinkle. None of the panels tested, however, failed catastrophically in the weld-braze joint. Experimental test results are in good agreement with structural analysis of the panels.

  15. Fast diffusion along defects and corrugations in phospholipid P beta, liquid crystals.

    PubMed

    Schneider, M B; Chan, W K; Webb, W W

    1983-08-01

    The diffusion of a fluorescent lipid analogue in liquid crystals of the anisotropic P beta, phase of dimyristoylphosphatidylcholine (DMPC) had been found to be highly variable, suggesting structural defect pathways. Fluorescence photobleaching recovery (FPR) experiments imply two effective diffusion pathways with coefficients differing by at least 100. This is consistent with fast diffusion along submicroscopic bands of disordered material ("defects") in the bilayer corrugations characteristic of this phase. Due to strains during transformation from the L alpha phase, the axis of the corrugations is ordinarily disrupted by mosaic patches rotationally disoriented within the mean plane of the molecular bilayers, although larger oriented domains are sometimes adventitiously aligned into microscopically visible striped textures. The corrugations are also systematically aligned along positive disclinations pairs or "oily streaks." Thus, fast diffusion occurs parallel to the disclination lines and along the textured stripes. FPR results yield an upper limit on the effective diffusion in the ordered material of D less than or equal to 2 X 10(-16) cm2/s at 22 degrees C, D less than or equal to 3 X 10(-17) cm2/s at 13 degrees C. In contrast the diffusion coefficient along defect pathways where disordered ribbons are aligned is D approximately 4 X 10(-11) cm2/s at 16 degrees C. PMID:6616004

  16. 49 CFR 195.114 - Used pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 3 2011-10-01 2011-10-01 false Used pipe. 195.114 Section 195.114 Transportation...PIPELINE Design Requirements § 195.114 Used pipe. Any used pipe installed in a pipeline system must comply with §...

  17. 49 CFR 195.114 - Used pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 3 2010-10-01 2010-10-01 false Used pipe. 195.114 Section 195.114 Transportation...PIPELINE Design Requirements § 195.114 Used pipe. Any used pipe installed in a pipeline system must comply with §...

  18. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  19. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  20. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  1. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  2. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  3. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  4. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  5. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  6. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  7. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  8. Large-bore pipe decontamination

    SciTech Connect

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system.

  9. Ceramic heat pipe wick

    NASA Technical Reports Server (NTRS)

    Seidenberg, Benjamin (inventor); Swanson, Theodore (inventor)

    1989-01-01

    A wick for use in a capillary loop pump heat pipe is disclosed. The wick material is an essentially uniformly porous, permeable, open-cell, silicon dioxide/aluminum oxide inorganic ceramic foam having a silica fiber ratio, by weight, of about 78 to 22, respectively, a density of 6 lbs/cu ft, and an average pore size of less than 5 microns. A representative material having these characteristics is Lockheed Missile and Space Company, Inc.'s HTP 6-22. This material is fully compatible with the freons and anhydrous ammonia and allows for the use of these very efficient working fluids, and others, in capillary loops.

  10. Polymeric heat pipe wick

    NASA Technical Reports Server (NTRS)

    Seidenberg, Benjamin

    1988-01-01

    A wick for use in a capillary loop pump heat pipe is described. The wick material is an essentially uniformly porous, permeable, open-cell, polyethylene thermoplastic foam having an ultrahigh average molecular weight of from approximately 1 to 5 million, and an average pore size of about 10 to 12 microns. A representative material having these characteristics is POREX UF, which has an average molecular weight of about 3 million. This material is fully compatible with the FREONs and anhydrous ammonia and allows for the use of these very efficient working fluids in capillary loops.

  11. A Multifrequency Notch Filter for Millimeter Wave Plasma Diagnostics based on Photonic Bandgaps in Corrugated Circular Waveguides

    NASA Astrophysics Data System (ADS)

    Wagner, D.; Bongers, W.; Kasparek, W.; Leuterer, F.; Monaco, F.; Münich, M.; Schütz, H.; Stober, J.; Thumm, M.; Brand, H. v. d.

    2015-03-01

    Sensitive millimeter wave diagnostics need often to be protected against unwanted radiation like, for example, stray radiation from high power Electron Cyclotron Heating applied in nuclear fusion plasmas. A notch filter based on a waveguide Bragg reflector (photonic band-gap) may provide several stop bands of defined width within up to two standard waveguide frequency bands. A Bragg reflector that reflects an incident fundamental TE11 into a TM1n mode close to cutoff is combined with two waveguide tapers to fundamental waveguide diameter. Here the fundamental TE11 mode is the only propagating mode at both ends of the reflector. The incident TE11 mode couples through the taper and is converted to the high order TM1n mode by the Bragg structure at the specific Bragg resonances. The TM1n mode is trapped in the oversized waveguide section by the tapers. Once reflected at the input taper it will be converted back into the TE11 mode which then can pass through the taper. Therefore at higher order Bragg resonances, the filter acts as a reflector for the incoming TE11 mode. Outside of the Bragg resonances the TE11 mode can propagate through the oversized waveguide structure with only very small Ohmic attenuation compared to propagating in a fundamental waveguide. Coupling to other modes is negligible in the non-resonant case due to the small corrugation amplitude (typically 0.05·?0, where ?0 is the free space wavelength). A Bragg reflector for 105 and 140 GHz was optimized by mode matching (scattering matrix) simulations and manufactured by SWISSto12 SA, where the required mechanical accuracy of ± 5 ?m could be achieved by stacking stainless steel rings, manufactured by micro-machining, in a high precision guiding pipe. The two smooth-wall tapers were fabricated by electroforming. Several measurements were performed using vector network analyzers from Agilent (E8362B), ABmm (MVNA 8-350) and Rohde&Schwarz (ZVA24) together with frequency multipliers. The stop bands around 105 GHz (- 55dB) and 140 GHz (-60dB) correspond to the TE11-TM12 and TE11-TM13 Bragg resonances. Experiments are in good agreement with theory.

  12. 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)

  13. Demonstrating Sound Impulses in Pipes.

    ERIC Educational Resources Information Center

    Raymer, M. G.; Micklavzina, Stan

    1995-01-01

    Describes a simple, direct method to demonstrate the effects of the boundary conditions on sound impulse reflections in pipes. A graphical display of the results can be made using a pipe, cork, small hammer, microphone, and fast recording electronics. Explains the principles involved. (LZ)

  14. Heat Pipe Blocks Return Flow

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1982-01-01

    Metal-foil reed valve in conventional slab-wick heat pipe limits heat flow to one direction only. With sink warmer than source, reed is forced closed and fluid returns to source side through annular transfer wick. When this occurs, wick slab on sink side of valve dries out and heat pipe ceases to conduct heat.

  15. Alternate high capacity heat pipe

    NASA Technical Reports Server (NTRS)

    Voss, F. E.

    1986-01-01

    The performance predictions for a fifty foot heat pipe (4 foot evaporator - 46 foot condensor) are discussed. These performance predictions are supported by experimental data for a four foot heat pipe. Both heat pipes have evaporators with axial groove wick structures and condensers with powder metal external artery wick structures. The predicted performance of a rectangular axial groove/external artery heat pipe operating in space is given. Heat transport versus groove width is plotted for 100, 200 and 300 grooves in the evaporator. The curves show that maximum power is achieved for groove widths from 0.040 to 0.053 as the number of grooves varies from 300 to 100. The corresponding range of maximum power is 3150 to 2400 watts. The relationships between groove width and heat pipe evaporate diameter for 100, 200 and 300 grooves in the evaporator are given. A four foot heat pipe having a three foot condenser and one foot evaporator was built and tested. The evaporator wick structure used axial grooves with rectangular cross sections, and the condenser wick structure used powder metal with an external artery configuration. Fabrication drawings are enclosed. The predicted and measured performance for this heat pipe is shown. The agreement between predicted and measured performance is good and therefore substantiates the predicted performance for a fifty foot heat pipe.

  16. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, William T. (Martinez, GA); Treanor, Richard C. (Augusta, GA)

    1994-01-01

    A pipe crawler having a midsection that provides the stability and flexibty to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in "inch worm" fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting.

  17. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, W.T.; Treanor, R.C.

    1994-12-27

    A pipe crawler is described having a midsection that provides the stability and flexibility to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in ''inch worm'' fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting. 5 figures.

  18. Vapor spill pipe monitor

    DOEpatents

    Bianchini, G.M.; McRae, T.G.

    1983-06-23

    The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

  19. Los Alamos National Laboratory corregated metal pipe saw facility preliminary safety analysis report. Volume I

    SciTech Connect

    1990-09-19

    This Preliminary Safety Analysis Report addresses site assessment, facility design and construction, and design operation of the processing systems in the Corrugated Metal Pipe Saw Facility with respect to normal and abnormal conditions. Potential hazards are identified, credible accidents relative to the operation of the facility and the process systems are analyzed, and the consequences of postulated accidents are presented. The risk associated with normal operations, abnormal operations, and natural phenomena are analyzed. The accident analysis presented shows that the impact of the facility will be acceptable for all foreseeable normal and abnormal conditions of operation. Specifically, under normal conditions the facility will have impacts within the limits posted by applicable DOE guidelines, and in accident conditions the facility will similarly meet or exceed the requirements of all applicable standards. 16 figs., 6 tabs.

  20. Promethus Hot Leg Piping Concept

    SciTech Connect

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  1. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, Charles F. (Aiken, SC); Howard, Boyd D. (Augusta, GA)

    1998-01-01

    A flexible, modular ultrasonic pipe inspection apparatus, comprising a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present.

  2. Prometheus Hot Leg Piping Concept

    SciTech Connect

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-30

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  3. Technology for concrete pipe manipulator

    NASA Astrophysics Data System (ADS)

    Li, Bin; Wang, Dan; Lin, Renzhi

    2010-01-01

    The pipe manipulator is a developing mechatronic system to enhance productivity and protects workers from cave-ins in the trench while excavating and laying pipe. The pipe manipulator is for installing concrete pipe into the trench. It is an optical-electro-mechanical system. The mechanism is make up of two parts, the upside and underside. The upside is for lifting the equipment by backhoe and rotating the underside mechanism. It includes rigidity lift beams, holding pad, four-bar linkages, hydraulic cylinder, rotating support, and rotating mechanism. Holding pad will press the bucket back to keep the bucket hooking the pipe man safely and stably. The underside mechanism is for lifting, holding and adjusting the pipe section's stance. The underside mechanism includes support trolley, and lift fork. The support trolley is driven by hydraulic cylinder for moving the fork forward or backward while laying a pipe into trench. The fork is with a self-lock mechanism for preventing the pipe from slide out of the prongs. A new photoelectric locating system is developed for auto-measuring the installing pipe section's stance within the work area. The laser target has been developed as a key part in the photoelectric locating systems. The photoelectric target is a rotating polar coordinate. Photodiodes are used for making the polar radius. There is an angular displacement sensor sitting on the heart-axis of the target for measuring angle of the target rotating. The pipe manipulator can be located by the system, and the locating methods have been presented at last of the paper.

  4. Technology for concrete pipe manipulator

    NASA Astrophysics Data System (ADS)

    Li, Bin; Wang, Dan; Lin, Renzhi

    2009-12-01

    The pipe manipulator is a developing mechatronic system to enhance productivity and protects workers from cave-ins in the trench while excavating and laying pipe. The pipe manipulator is for installing concrete pipe into the trench. It is an optical-electro-mechanical system. The mechanism is make up of two parts, the upside and underside. The upside is for lifting the equipment by backhoe and rotating the underside mechanism. It includes rigidity lift beams, holding pad, four-bar linkages, hydraulic cylinder, rotating support, and rotating mechanism. Holding pad will press the bucket back to keep the bucket hooking the pipe man safely and stably. The underside mechanism is for lifting, holding and adjusting the pipe section's stance. The underside mechanism includes support trolley, and lift fork. The support trolley is driven by hydraulic cylinder for moving the fork forward or backward while laying a pipe into trench. The fork is with a self-lock mechanism for preventing the pipe from slide out of the prongs. A new photoelectric locating system is developed for auto-measuring the installing pipe section's stance within the work area. The laser target has been developed as a key part in the photoelectric locating systems. The photoelectric target is a rotating polar coordinate. Photodiodes are used for making the polar radius. There is an angular displacement sensor sitting on the heart-axis of the target for measuring angle of the target rotating. The pipe manipulator can be located by the system, and the locating methods have been presented at last of the paper.

  5. Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    DOEpatents

    Fischer, William H. (Pittsburgh, PA)

    1984-01-01

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly.

  6. Non-contact gears: I. Next-to-leading order contribution to lateral Casimir force between corrugated parallel plates

    E-print Network

    Ines Cavero-Pelaez; Kimball A. Milton; Prachi Parashar; K. V. Shajesh

    2008-07-03

    We calculate the lateral Casimir force between corrugated parallel plates, described by $\\delta$-function potentials, interacting through a scalar field, using the multiple scattering formalism. The contributions to the Casimir energy due to uncorrugated parallel plates is treated as a background from the outset. We derive the leading- and next-to-leading-order contribution to the lateral Casimir force for the case when the corrugation amplitudes are small in comparison to corrugation wavelengths. We present explicit results in terms of finite integrals for the case of the Dirichlet limit, and exact results for the weak-coupling limit, for the leading- and next-to-leading-orders. The correction due to the next-to-leading contribution is significant. In the weak coupling limit we calculate the lateral Casimir force exactly in terms of a single integral which we evaluate numerically. Exact results for the case of the weak limit allows us to estimate the error in the perturbative results. We show that the error in the lateral Casimir force, in the weak coupling limit, when the next-to-leading order contribution is included is remarkably low when the corrugation amplitudes are small in comparison to corrugation wavelengths. We expect similar conclusions to hold for the Dirichlet case. The analogous calculation for the electromagnetic case should reduce the theoretical error sufficiently for comparison with the experiments.

  7. Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    SciTech Connect

    Fischer, W.H.

    1984-04-24

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly. 7 figs.

  8. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 27.1123 Section 27.1123... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping... operating temperatures. (b) Exhaust piping must be supported to withstand any vibration and inertia loads...

  9. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  10. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck— (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  11. Determination of Secondary Encasement Pipe Design Pressure

    SciTech Connect

    TEDESCHI, A.R.

    2000-10-26

    This document published results of iterative calculations for maximum tank farm transfer secondary pipe (encasement) pressure upon failure of the primary pipe. The maximum pressure was calculated from a primary pipe guillotine break. Results show encasement pipeline design or testing pressures can be significantly lower than primary pipe pressure criteria.

  12. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...660 Pipe welding. (a) Pipe welding must meet part 57 of...following: (1) Butt welds of pipes made from carbon, carbon...requirements for post-weld heat treatment. (2) Except for...or (ii) The nominal pipe diameter is greater than...

  13. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...660 Pipe welding. (a) Pipe welding must meet part 57 of...following: (1) Butt welds of pipes made from carbon, carbon...requirements for post-weld heat treatment. (2) Except for...or (ii) The nominal pipe diameter is greater than...

  14. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...660 Pipe welding. (a) Pipe welding must meet part 57 of...following: (1) Butt welds of pipes made from carbon, carbon...requirements for post-weld heat treatment. (2) Except for...or (ii) The nominal pipe diameter is greater than...

  15. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...3 2011-10-01 2011-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...Materials Other Than by Welding § 192.279 Copper pipe. Copper pipe may not be threaded except that copper pipe...

  16. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...Materials Other Than by Welding § 192.279 Copper pipe. Copper pipe may not be threaded except that copper pipe...

  17. Heat pipe technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A cumulative bibliography on heat pipe research and development projects is presented. The subjects discussed are: (1) general information, (2) heat pipe applications, (3) heat pipe theory, (4) design and fabrication, (5) testing and operation, (6) subject and author index, and (7) heat pipe related patents.

  18. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  19. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  20. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  1. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  2. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  3. Heat pipe technology: A biblography with abstracts

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A bibliography of heat pipe research and development projects conducted during April through June 1972, is presented. The subjects discussed are: (1) general information, (2) heat pipe applications, (3) heat pipe theory, (4) design and fabrication, (5) test and operation, (6) subject and author index, and (7) heat pipe related patents.

  4. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck— (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  5. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck— (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  6. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems § 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under § 56.07-10 of this chapter and, if the design temperature is ?110 °C (?166...

  7. Hg supply piping simulation Stony Brook University

    E-print Network

    McDonald, Kirk

    Stress Model", Int. J. Numer. Meth. Fluids 2005; 47:1431­1449 #12;Hg supply piping in Muon Collider InletHg supply piping simulation (No MHD) Stony Brook University Yan Zhan Prof. Foluso Ladeinde July 2nd, 2010 #12;Outline · Hg supply piping in Muon Collider · Turbulence models for bend pipe flow · Problems

  8. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems § 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under § 56.07-10 of this chapter and, if the design temperature is ?110 °C (?166...

  9. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems § 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under § 56.07-10 of this chapter and, if the design temperature is ?110 °C (?166...

  10. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems § 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under § 56.07-10 of this chapter and, if the design temperature is ?110 °C (?166...

  11. Structural Assessment of Small Bore Feeder Piping

    E-print Network

    Sun, Yu

    STRESSES ON THE INTE- RIOR SURFACE OF THE PIPE AT THE LOCALLY THINNED FLAW. FURTHER TESTINGBACKGROUND Structural Assessment of Small Bore Feeder Piping Kathryn Tang, Janos Mann, Skerdi. Supervisor: A. N. Sinclair CASE ONE CANDU REACTORS HAVE 380+ SMALL BORE FEEDER PIPES. THE PIPES

  12. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems § 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under § 56.07-10 of this chapter and, if the design temperature is ?110 °C (?166...

  13. Laser profiling of sewer pipes Laser profiling of sewer pipes

    E-print Network

    Langendoen, Koen

    has to be available about the state of an asset. Nowadays CCTV inspections and pipe age are the main of. A laser profiler, as an adjunct to CCTV, can identify the profile of a sewer and also wall loss

  14. Heat pipe transient response approximation

    NASA Astrophysics Data System (ADS)

    Reid, Robert S.

    2002-01-01

    A simple and concise routine that approximates the response of an alkali metal heat pipe to changes in evaporator heat transfer rate is described. This analytically based routine is compared with data from a cylindrical heat pipe with a crescent-annular wick that undergoes gradual (quasi-steady) transitions through the viscous and condenser boundary heat transfer limits. The sonic heat transfer limit can also be incorporated into this routine for heat pipes with more closely coupled condensers. The advantages and obvious limitations of this approach are discussed. For reference, a source code listing for the approximation appears at the end of this paper. .

  15. Abrasion protection in process piping

    SciTech Connect

    Accetta, J.

    1996-07-01

    Process piping often is subjected to failure from abrasion or a combination of abrasion and corrosion. Abrasion is a complex phenomenon, with many factors involved to varying degrees. Hard, mineral based alumina ceramic and basalt materials are used to provide protection against abrasion in many piping systems. Successful life extension examples are presented from many different industries. Lined piping components require special attention with regard to operating conditions as well as design and engineering considerations. Economic justification involves direct cost comparisons and avoided costs.

  16. Thermal laminarization of a stratified pipe flow

    SciTech Connect

    Oras, J.J.; Kasza, K.E.

    1984-01-01

    The present work constitutes a new program that grew out of a scoping assessment by ANL to determine the propensity for pipe stratification to occur in the reactor outlet nozzles and hot-leg piping of a generic LMFBR during events producing reverse pipe flow. This paper focuses on the role that thermal buoyancy plays relative to being able to laminarize a turbulent stratified shear zone in a horizontal pipe. The preceeding can influence the behavior of a pipe stratified-backflow-recirculation zone (cold plenum water down into the hot pipe flow) which developes as the result of a temperature difference between the pipe flow and the plenum.

  17. Training reduces stuck pipe costs and incidents

    SciTech Connect

    Watson, B. ); Smith, R. )

    1994-09-19

    Properly administered initial and refresher stuck pipe training courses have dramatically reduced the cost and number of stuck pipe incidents for many companies worldwide. These training programs have improved operator and contractor crew awareness of stuck pipe risks and fostered a team commitment in averting such incidents. The success is evident in the achievements of the companies sponsoring such training. Preventing and minimizing stuck pipe is the most significant benefit of stuck pipe training, but crews also benefit from becoming more knowledgeable about the drilling program and equipment operation. The paper discusses stuck pipe costs, stuck pipe training, prevention of stuck pipes, well bore stability, geopressured formation, reactive formation, reactive formations, unconsolidated formations, mobile formations, fractured and faulted formations, differential sticking, 8 other causes of stuck pipe, and freeing stuck pipe.

  18. Dual nature of localization in guiding systems with randomly corrugated boundaries: Anderson-type versus entropic

    NASA Astrophysics Data System (ADS)

    Tarasov, Yu. V.; Shostenko, L. D.

    2015-05-01

    A unified theory for the conductance of an infinitely long multimode quantum wire whose finite segment has randomly rough lateral boundaries is developed. It enables one to rigorously take account of all feasible mechanisms of wave scattering, both related to boundary roughness and to contacts between the wire rough section and the perfect leads within the same technical frameworks. The rough part of the conducting wire is shown to act as a mode-specific randomly modulated effective potential barrier whose height is governed essentially by the asperity slope. The mean height of the barrier, which is proportional to the average slope squared, specifies the number of conducting channels. Under relatively small asperity amplitude this number can take on arbitrary small, up to zero, values if the asperities are sufficiently sharp. The consecutive channel cut-off that arises when the asperity sharpness increases can be regarded as a kind of localization, which is not related to the disorder per se but rather is of entropic or (equivalently) geometric origin. The fluctuating part of the effective barrier results in two fundamentally different types of guided wave scattering, viz., inter- and intramode scattering. The intermode scattering is shown to be for the most part very strong except in the cases of (a) extremely smooth asperities, (b) excessively small length of the corrugated segment, and (c) the asperities sharp enough for only one conducting channel to remain in the wire. Under strong intermode scattering, a new set of conducting channels develops in the corrugated waveguide, which have the form of asymptotically decoupled extended modes subject to individual solely intramode random potentials. In view of this fact, two transport regimes only are realizable in randomly corrugated multimode waveguides, specifically, the ballistic and the localized regime, the latter characteristic of one-dimensional random systems. Two kinds of localization are thus shown to coexist in waveguide-like systems with randomly corrugated boundaries, specifically, the entropic localization and the one-dimensional Anderson (disorder-driven) localization. If the particular mode propagates across the rough segment ballistically, the Fabry-Pérot-type oscillations should be observed in the conductance, which are suppressed for the mode transferred in the Anderson-localized regime.

  19. Radiation characteristics of electromagnetic eigenmodes at the corrugated interface of a left-handed material.

    PubMed

    Cuevas, Mauro; Depine, Ricardo A

    2009-08-28

    We study the radiation characteristics of electromagnetic surface waves at a periodically corrugated interface between a conventional and a negatively refracting (or left-handed) material. In this case, and contrary to the surface plasmon polariton in a metallic grating, surface plasmon polaritons may radiate on both sides of the rough interface along which they propagate. We find novel radiation regimes which provide an indirect demonstration of other unusual phenomena characteristic of electromagnetic wave propagation in left-handed materials, such as negative refraction or backward wave propagation. PMID:19792827

  20. Eddy Current System for Detection of Cracking Beneath Braiding in Corrugated Metal Hose

    NASA Technical Reports Server (NTRS)

    Wincheski, Buzz; Simpson, John; Hall, George

    2008-01-01

    In this paper an eddy current system for the detection of partially-through-the-thickness cracks in corrugated metal hose is presented. Design criteria based upon the geometry and conductivity of the part are developed and applied to the fabrication of a prototype inspection system. Experimental data are used to highlight the capabilities of the system and an image processing technique is presented to improve flaw detection capabilities. A case study for detection of cracking damage in a space shuttle radiator retract flex hoses is also presented.

  1. Pneumatic Pressure Cell with Twin Diaphragms Embedding Spherical Corrugations in a Dual Diaphragm Structure

    E-print Network

    Cellatoglu, A

    2012-01-01

    Thin metallic shallow spherical diaphragms are being used for measuring pneumatic pressure in process industries. The drift in vertex realized due to application of pressure is transformed into electrical signal and this is calibrated for pressure. We now propose a modified structure for the pressure cell by having double ended shallow spherical shells embedded with spherical corrugations as to enhance the sensitivity to a greater extent. By having dual such installation in the structure of the pressure cell it concedes further increase in sensitivity. The construction details of the diaphragm structure, theory and analysis to assess the performance are presented.

  2. Tailoring of spectral response and spatial field distribution with corrugated photonic crystal slab.

    PubMed

    Gad, Raanan; Lau, Wah Tung; Nicholaou, Costa; Ahmadi, Soroosh; Sigal, Iliya; Levi, Ofer

    2015-08-15

    We report a new physical mechanism for simultaneous tuning of quality factors, spectral responses, and field distributions in photonic crystal slabs through removal of polarization mode degeneracy using a lattice of elliptical nano-holes. The quality factors in these structures can become higher than those obtained with much smaller circular nano-holes. Furthermore, the modes can be superimposed by either rotating or morphing the elliptical nano-holes into a corrugated grating. These findings will enable improved radiation-matter interaction in optical, microwave, and THZ frequencies along with enhanced opto-acoustic coupling. PMID:26274642

  3. EDDY CURRENT SYSTEM FOR DETECTION OF CRACKING BENEATH BRAIDING IN CORRUGATED METAL HOSE

    SciTech Connect

    Wincheski, Buzz; Simpson, John; Hall, George

    2009-03-03

    In this paper an eddy current system for the detection of partially-through-the-thickness cracks in corrugated metal hose is presented. Design criteria based upon the geometry and conductivity of the part are developed and applied to the fabrication of a prototype inspection system. Experimental data are used to highlight the capabilities of the system and an image processing technique is presented to improve flaw detection capabilities. A case study for detection of cracking damage in a space shuttle radiator retract flex hoses is also presented.

  4. Analysis of Bonded Joints Between the Facesheet and Flange of Corrugated Composite Panels

    NASA Technical Reports Server (NTRS)

    Yarrington, Phillip W.; Collier, Craig S.; Bednarcyk, Brett A.

    2008-01-01

    This paper outlines a method for the stress analysis of bonded composite corrugated panel facesheet to flange joints. The method relies on the existing HyperSizer Joints software, which analyzes the bonded joint, along with a beam analogy model that provides the necessary boundary loading conditions to the joint analysis. The method is capable of predicting the full multiaxial stress and strain fields within the flange to facesheet joint and thus can determine ply-level margins and evaluate delamination. Results comparing the method to NASTRAN finite element model stress fields are provided illustrating the accuracy of the method.

  5. Distributed-feedback Terahertz Quantum-cascade Lasers with Laterally Corrugated Metal Waveguides

    NASA Technical Reports Server (NTRS)

    Williams, Benjamin S.; Kumar, Sushil; Hu, Qing; Reno, John L.

    2005-01-01

    We report the demonstration of distributed-feedback terahertz quantum-cascade lasers based on a first-order grating fabricated via a lateral corrugation in a double-sided metal ridge waveguide. The phase of the facet reflection was precisely set by lithographically defined facets by dry etching. Single-mode emission was observed at low to moderate injection currents, although multimode emission was observed far beyond threshold owing to spatial hole burning. Finite-element simulations were used to calculate the modal and threshold characteristics for these devices, with results in good agreement with experiments.

  6. Importance of the Darrieus-Landau instability for strongly corrugated turbulent flames.

    PubMed

    Bychkov, Vitaly

    2003-12-01

    The renormalization ideas of self-similar dynamics of a strongly turbulent flame front are applied to the case of a flame with realistically large thermal expansion of the burning matter. In that case a flame front is corrugated both by the external turbulence and by the intrinsic flame instability (the Darrieus-Landau instability). The analytical formulas for the velocity of flame propagation are obtained. It is demonstrated that the flame instability is of principal importance when the maximal hydrodynamic length scale is much larger than the cutoff wavelength of the instability, provided the turbulent intensity is not too high. PMID:14754312

  7. Shear Lag in Corrugated Sheets Used for the Chord Member of a Box Beam

    NASA Technical Reports Server (NTRS)

    Newell, Joseph S; Reissner, Eric

    1941-01-01

    The problem of the distribution of normal stress across a wide corrugated sheet used as the chord of a box-beam-like structure is investigated theoretically and experimentally. Expressions are developed giving the stress distribution in beams, symmetrical or unsymmetrical, about a plane passed spanwise through the center of the sheet. The experiments were arranged to insure bending without torsion and surveys of the normal stresses were made by means of mechanical and electrical strain gages. The experimental data showed very good agreement with the new b of the theoretical curves, especially at the highly stressed sections, for both the symmetrical and unsymmetrical beams. Several suggestions for future research are included.

  8. Escape beam statistics and dynamical properties for a periodically corrugated waveguide

    NASA Astrophysics Data System (ADS)

    da Costa, Diogo Ricardo; Silva, Mário R.; Leonel, Edson D.

    2014-04-01

    Some escape and dynamical properties for a beam of light inside a corrugated waveguide are discussed by using Fresnel reflectance. The system is described by a mapping and is controlled by a parameter ? defining a transition from integrability (?=0) to non integrability (??0). The phase space is mixed containing periodic islands, chaotic seas and invariant tori. The histogram of escaping orbits is shown to be scaling invariant with respect to ?. The waveguide is immersed in a region with different refractive index. Different optical materials are used to overcame the results.

  9. B Plant process piping replacement feasibility study

    SciTech Connect

    Howden, G.F.

    1996-02-07

    Reports on the feasibility of replacing existing embedded process piping with new more corrosion resistant piping between cells and between cells and a hot pipe trench of a Hanford Site style canyon facility. Provides concepts for replacement piping installation, and use of robotics to replace the use of the canyon crane as the primary means of performing/supporting facility modifications (eg, cell lining, pipe replacement, equipment reinstallation) and operational maintenenace.

  10. Intermediate Temperature Water Heat Pipe Tests

    NASA Technical Reports Server (NTRS)

    Devarakonda, Angirasa; Xiong, Daxi; Beach, Duane E.

    2004-01-01

    Heat pipes are among the most promising technologies for space radiator systems. Water heat pipes are explored in the intermediate temperature range of 400 to above 500 K. The thermodynamic and thermo-physical properties of water are reviewed in this temperature range. Test Data are reported for a copper-water heat pipe. The heat pipe was tested under different orientations. Water heat pipes show promise in this temperature range.Fabrication and testing issues are being addressed.

  11. Intermediate Temperature Water Heat Pipe Tests

    NASA Technical Reports Server (NTRS)

    Devarakonda, Angirasa; Xiong, Da-Xi; Beach, Duane E.

    2005-01-01

    Heat pipes are among the most promising technologies for space radiator systems. Water heat pipes are explored in the intermediate temperature range of 400 to above 500 K. The thermodynamic and thermo-physical properties of water are reviewed in this temperature range. Test data are reported for a copper-water heat pipe. The heat pipe was tested under different orientations. Water heat pipes show promise in this temperature range. Fabrication and testing issues are being addressed.

  12. (In preparation for submission to Physical Review Letters) Spontaneous nanoscale corrugation of ion-eroded SiO2 : the role of ion

    E-print Network

    Headrick, Randall L.

    of ion-eroded SiO2 : the role of ion irradiation-enhanced viscous flow Christopher C. Umbach,1 Randall L-ray scattering was used to determine the temperature and ion-energy dependence of nanoscale corrugations that form on an amorphous SiO2 surface eroded by Ar+ ions. The corrugation wavelength * shows a nearly

  13. Heat pipe radiators for space

    NASA Technical Reports Server (NTRS)

    Sellers, J. P.

    1976-01-01

    Analysis of the data heat pipe radiator systems tested in both vacuum and ambient environments was continued. The systems included (1) a feasibility VCHP header heat-pipe panel, (2) the same panel reworked to eliminate the VCHP feature and referred to as the feasibility fluid header panel, and (3) an optimized flight-weight fluid header panel termed the 'prototype.' A description of freeze-thaw thermal vacuum tests conducted on the feasibility VCHP was included. In addition, the results of ambient tests made on the feasibility fluid header are presented, including a comparison with analytical results. A thermal model of a fluid header heat pipe radiator was constructed and a computer program written. The program was used to make a comparison of the VCHP and fluid-header concepts for both single and multiple panel applications. The computer program was also employed for a parametric study, including optimum feeder heat pipe spacing, of the prototype fluid header.

  14. Physics of heat pipe rewetting

    NASA Technical Reports Server (NTRS)

    Chan, S. H.

    1994-01-01

    This is the final report which summarizes the research accomplishments under the project entitled 'Physics of Heat Pipe Rewetting' under NASA Grant No. NAG 9-525, Basic, during the period of April 1, 1991 to January 31, 1994. The objective of the research project was to investigate both analytically and experimentally the rewetting characteristics of the heated, grooved plate. The grooved plate is to simulate the inner surface of the vapor channel in monogroove heat pipes for space station design. In such designs, the inner surface of the vapor channel is threaded with monogrooves. When the heat pipe is thermally overloaded, dryout of the monogroove surface occurs. Such a dryout surface should be promptly rewetted to prevent the failure of the heat pipe operation in the thermal radiator of the space station.

  15. Method for casting polyethylene pipe

    NASA Technical Reports Server (NTRS)

    Elam, R. M., Jr.

    1973-01-01

    Short lengths of 7-cm ID polyethylene pipe are cast in a mold which has a core made of room-temperature-vulcanizable (RTV) silicone. Core expands during casting and shrinks on cooling to allow for contraction of the polyethylene.

  16. Heat Pipes: An Industrial Application 

    E-print Network

    Murray, F.

    1984-01-01

    This paper reviews the basics of heat pipe exchangers. Included are how they are constructed, how they operate, where they have application, and various aspects of evaluating a potential application. After discussing the technical aspects of heat...

  17. Loop Heat Pipe Startup Behaviors

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2014-01-01

    A loop heat pipe must start successfully before it can commence its service. The start-up transient represents one of the most complex phenomena in the loop heat pipe operation. This paper discusses various aspects of loop heat pipe start-up behaviors. Topics include the four start-up scenarios, the initial fluid distribution between the evaporator and reservoir that determines the start-up scenario, factors that affect the fluid distribution between the evaporator and reservoir, difficulties encountered during the low power start-up, and methods to enhance the start-up success. Also addressed are the thermodynamic constraint between the evaporator and reservoir in the loop heat pipe operation, the superheat requirement for nucleate boiling, pressure spike and pressure surge during the start-up transient, and repeated cycles of loop start-up andshutdown under certain conditions.

  18. Light pipes for LED measurements

    NASA Technical Reports Server (NTRS)

    Floyd, S. R.; Thomas, E. F., Jr.

    1976-01-01

    Light pipe directly couples LED optical output to single detector. Small area detector measures total optical output of diode. Technique eliminates thermal measurement problems and channels optical output to remote detector.

  19. Heat Pipe Thermal Conditioning Panel

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.

    1973-01-01

    The technology involved in designing and fabricating a heat pipe thermal conditioning panel to satisfy a broad range of thermal control system requirements on NASA spacecraft is discussed. The design specifications were developed for a 30 by 30 inch heat pipe panel. The fundamental constraint was a maximum of 15 gradient from source to sink at 300 watts input and a flux density of 2 watts per square inch. The results of the performance tests conducted on the panel are analyzed.

  20. Pipe weld crown removal device

    DOEpatents

    Sword, Charles K. (Pleasant Hills, PA); Sette, Primo J. (West Newton, PA)

    1992-01-01

    A device is provided for grinding down the crown of a pipe weld joining aligned pipe sections so that the weld is substantially flush with the pipe sections joined by the weld. The device includes a cage assembly comprising a pair of spaced cage rings adapted to be mounted for rotation on the respective pipe sections on opposite sides of the weld, a plurality of grinding wheels, supported by the cage assembly for grinding down the crown of the weld, and a plurality of support shafts, each extending longitudinally along the joined pipe sections, parallel thereto, for individually mounting respective grinding wheels. Each end of the support shafts is mounted for rotation in a bearing assembly housed within a radially directed opening in a corresponding one of the cage rings so as to provide radial movement of the associated shaft, and thus of the associated grinding wheel, towards and away from the weld. A first drive sprocket provides rotation of the cage assembly around the pipe sections while a second drive unit, driven by a common motor, provides rotation of the grinding wheels.

  1. Heat pipe cooled power magnetics

    NASA Technical Reports Server (NTRS)

    Chester, M. S.

    1979-01-01

    A high frequency, high power, low specific weight (0.57 kg/kW) transformer developed for space use was redesigned with heat pipe cooling allowing both a reduction in weight and a lower internal temperature rise. The specific weight of the heat pipe cooled transformer was reduced to 0.4 kg/kW and the highest winding temperature rise was reduced from 40 C to 20 C in spite of 10 watts additional loss. The design loss/weight tradeoff was 18 W/kg. Additionally, allowing the same 40 C winding temperature rise as in the original design, the KVA rating is increased to 4.2 KVA, demonstrating a specific weight of 0.28 kg/kW with the internal loss increased by 50W. This space environment tested heat pipe cooled design performed as well electrically as the original conventional design, thus demonstrating the advantages of heat pipes integrated into a high power, high voltage magnetic. Another heat pipe cooled magnetic, a 3.7 kW, 20A input filter inductor was designed, developed, built, tested, and described. The heat pipe cooled magnetics are designed to be Earth operated in any orientation.

  2. Superconducting pipes and levitating magnets

    E-print Network

    Yan Levin; Felipe B. Rizzato

    2006-09-15

    Motivated by a beautiful demonstration of the Faraday's and Lenz's law in which a small neodymium magnet falls slowly through a conducting non-ferromagnetic tube, we consider the dynamics of a magnet falling through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be suspended over the front edge. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius $a$ and length $L \\approx a$ decays, in the axial direction, with a characteristic length $\\xi \\approx 0.26 a$. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices, SQUIDs. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.

  3. Automated internal pipe cutting device

    DOEpatents

    Godlewski, William J. (Clifton Park, NY); Haffke, Gary S. (Ballston Spa, NY); Purvis, Dale (Amsterdam, NY); Bashar, Ronald W. (Oakdale, CT); Jones, Stewart D. (Mechanicville, NY); Moretti, Jr., Henry (Cranston, RI); Pimentel, James (Warwick, RI)

    2003-01-21

    The invention is a remotely controlled internal pipe cutting device primarily used for cutting pipes where the outside of the pipe is inaccessible at the line where the cut is to be made. The device includes an axial ram within a rotational cylinder which is enclosed in a housing. The housing is adapted for attachment to an open end of the pipe and for supporting the ram and cylinder in cantilever fashion within the pipe. A radially movable cutter, preferably a plasma arc torch, is attached to the distal end of the ram. A drive mechanism, containing motors and mechanical hardware for operating the ram and cylinder, is attached to the proximal end of the housing. The ram and cylinder provide for moving the cutter axially and circumferentially, and a cable assembly attached to a remote motor provide for the movement of the cutter radially, within the pipe. The control system can be adjusted and operated remotely to control the position and movement of the cutter to obtain the desired cut. The control system can also provide automatic standoff control for a plasma arc torch.

  4. Organ pipe resonance induced vibration in piping system

    SciTech Connect

    Wang, T.

    1996-12-01

    Acoustic-induced vibration is a fluid-structure interaction phenomenon. The feedback mechanism between the acoustic pressure pulsation and the structure movements determines the excited acoustic modes which, in turn, amplify the structure response when confidence frequency and mode shape matching occurs. The acoustic modes are not determined from the acoustic boundary conditions alone, structure feedback is as responsible for determining the acoustic modes and shaping the resulting forcing functions. Acoustic-induced piping vibration, when excited, does not attenuate much with distance. Pressure pulsation can be transmitted throughout the piping system and its branch connections. It is this property that makes vibration monitoring difficult, because vibration can surface at locations far away from the acoustic source when resonance occurs. For a large piping system with interconnected branches, the monitoring task can be formidable, particularly when there is no indication what the real source is. In organ pipe resonance induced vibration, the initiating acoustic source may be inconspicuous or unavoidable during operation. In these situations, the forcing function approach can offer an optimal tool for vibration assessment. The forcing function approach was used in the evaluation of a standby steam piping vibration problem. Monitoring locations and instrument specifications were determined from the acoustic eigenfunction profiles. Measured data confirmed the presence of coherent vibrations in the large bore piping. The developed forcing function permits design evaluation of the piping system, which leads to remedial actions and enables fatigue life determination, thus providing confidence to system operation. The forcing function approach is shown to be useful in finding potential vibration area and verifying the integrity of weak structure links. Application is to steam lines at BWR plants.

  5. Corrugation of Phase-Separated Lipid Bilayers Supported by Nanoporous Silica Xerogel Surfaces

    SciTech Connect

    Goksu, E I; Nellis, B A; Lin, W; Satcher Jr., J H; Groves, J T; Risbud, S H; Longo, M L

    2008-10-30

    Lipid bilayers supported by substrates with nanometer-scale surface corrugations holds interest in understanding both nanoparticle-membrane interactions and the challenges of constructing models of cell membranes on surfaces with desirable properties, e.g. porosity. Here, we successfully form a two-phase (gel-fluid) lipid bilayer supported by nanoporous silica xerogel. Surface topology, diffusion, and lipid density in comparison to mica-supported lipid bilayers were characterized by AFM, FRAP, FCS, and quantitative fluorescence microscopy, respectively. We found that the two-phase lipid bilayer follows the xerogel surface contours. The corrugation imparted on the lipid bilayer results in a lipid density that is twice that on a flat mica surface. In direct agreement with the doubling of actual bilayer area in a projected area, we find that the lateral diffusion coefficient (D) of lipids on xerogel ({approx}1.7 {micro}m{sup 2}/s) is predictably lower than on mica ({approx}4.1 {micro}m{sup 2}/s) by both FRAP and FCS techniques. Furthermore, the gel-phase domains on xerogel compared to mica were larger and less numerous. Overall, our results suggest the presence of a relatively defect-free continuous two-phase bilayer that penetrates approximately midway into the first layer of {approx}50 nm xerogel beads.

  6. Inkjet printing of UHF antennas on corrugated cardboards for packaging applications

    NASA Astrophysics Data System (ADS)

    Sowade, Enrico; Göthel, Frank; Zichner, Ralf; Baumann, Reinhard R.

    2015-03-01

    In this study, a method based on inkjet printing has been established to develop UHF antennas on a corrugated cardboard for packaging applications. The use of such a standardized, paper-based packaging substrate as material for printing electronics is challenging in terms of its high surface roughness and high ink absorption rate, especially when depositing very thin films with inkjet printing technology. However, we could obtain well-defined silver layers on the cardboard substrates due to a primer layer approach. The primer layer is based on a UV-curable ink formulation and deposited as well as the silver ink with inkjet printing technology. Industrial relevant printheads were chosen for the deposition of the materials. The usage of inkjet printing allows highest flexibility in terms of pattern design. The primer layer was proven to optimize the surface characteristics of the substrate, mainly reducing the surface roughness and water absorptiveness. Thanks to the primer layer approach, ultra-high-frequency (UHF) radio-frequency identification (RFID) antennas were deposited by inkjet printing on the corrugated cardboards. Along with the characterization and interpretation of electrical properties of the established conductive antenna patterns, the performance of the printed antennas were analyzed in detail by measuring the scattering parameter S11 and the antenna gain.

  7. Simple Correctors for Elimination of High-Order Modes in Corrugated Waveguide Transmission Lines

    PubMed Central

    Kowalski, Elizabeth J.; Shapiro, Michael A.; Temkin, Richard J.

    2014-01-01

    When using overmoded corrugated waveguide transmission lines for high power applications, it is necessary to control the mode content of the system. Ideally, overmoded corrugated transmission lines operate in the fundamental HE11 mode and provide low losses for long distances. Unwanted higher order modes (HOMs), particularly LP11 and HE12, are often excited in the experimental systems due to practical misalignments in the transmission line system. This paper discusses how the unwanted modes propagate along with the fundamental mode in the transmission line system by formulating an equation that relates the center of power offset and angle of propagation of a beam (for the HE11 and LP11 modes) or the waist size and phase front radius of curvature of a beam (for the HE11 and HE12 modes). By introducing two miter bend correctors into the transmission system—miter bends that have slightly angled or ellipsoidal mirrors—the HOMs can be precisely manipulated in the system. This technique can be used to eliminate small quantities of unwanted modes, thereby creating a nearly pure fundamental mode beam with minimal losses. Examples of these applications are calculated and show the theoretical conversion of up to 10% HOM content into the fundamental HE11 mode with minimal losses. PMID:25067859

  8. Study of the effects of corrugated wall structures due to blanket modules around ICRH antennas

    SciTech Connect

    Dumortier, Pierre; Louche, Fabrice; Messiaen, André; Vervier, Michel

    2014-02-12

    In future fusion reactors, and in ITER, the first wall will be covered by blanket modules. These blanket modules, whose dimensions are of the order of the ICRF wavelengths, together with the clearance gaps between them will constitute a corrugated structure which will interact with the electromagnetic waves launched by ICRF antennas. The conditions in which the grooves constituted by the clearance gaps between the blanket modules can become resonant are studied. Simple analytical models and numerical simulations show that mushroom type structures (with larger gaps at the back than at the front) can bring down the resonance frequencies, which could lead to large voltages in the gaps between the blanket modules and perturb the RF properties of the antenna if they are in the ICRF operating range. The effect on the wave propagation along the wall structure, which is acting as a spatially periodic (toroidally and poloidally) corrugated structure, and hence constitutes a slow wave structure modifying the wall boundary condition, is examined.

  9. Transmission Loss and Absorption of Corrugated Core Sandwich Panels With Embedded Resonators

    NASA Technical Reports Server (NTRS)

    Allen, Albert R.; Schiller, Noah H.; Zalewski, Bart F.; Rosenthal, Bruce N.

    2014-01-01

    The effect of embedded resonators on the diffuse field sound transmission loss and absorption of composite corrugated core sandwich panels has been evaluated experimentally. Two 1.219 m × 2.438 m panels with embedded resonator arrangements targeting frequencies near 100 Hz were evaluated using non-standard processing of ASTM E90-09 acoustic transmission loss and ASTM C423-09a room absorption test measurements. Each panel is comprised of two composite face sheets sandwiching a corrugated core with a trapezoidal cross section. When inlet openings are introduced in one face sheet, the chambers within the core can be used as embedded acoustic resonators. Changes to the inlet and chamber partition locations allow this type of structure to be tuned for targeted spectrum passive noise control. Because the core chambers are aligned with the plane of the panel, the resonators can be tuned for low frequencies without compromising the sandwich panel construction, which is typically sized to meet static load requirements. Absorption and transmission loss performance improvements attributed to opening the inlets were apparent for some configurations and inconclusive for others.

  10. Design and Fabrication of a Ring-Stiffened Graphite-Epoxy Corrugated Cylindrical Shell

    NASA Technical Reports Server (NTRS)

    Johnson, R., Jr.

    1978-01-01

    Design and fabrication of supplement test panels that represent key portions of the cylinder are described, as are supporting tests of coupons, sample joints, and stiffening ring elements. The cylindrical shell is a ring-stiffened, open corrugation design that uses T300/5208 graphite-epoxy tape as the basic material for the shell wall and stiffening rings. The test cylinder is designed to withstand bending loads producing the relatively low maximum load intensity in the shell wall of 1,576 N/cm. The resulting shell wall weight, including stiffening rings and fasteners, is 0.0156 kg/m. The shell weight achieved in the graphite-epoxy cylinder represents a weight saving of approximately 23 percent, compared to a comparable aluminum shell. A unique fabrication approach was used in which the cylinder wall was built in three flat segments, which were then wrapped to the cylindrical shape. Such an approach, made possible by the flexibility of the thin corrugated wall in a radial direction, proved to be a simple approach to building the test cylinder. Based on tooling and fabrication methods in this program, the projected costs of a production run of 100 units are reported.

  11. Atomic-scale friction modulated by potential corrugation in multi-layered graphene materials

    SciTech Connect

    Zhuang, Chunqiang; Liu, Lei

    2015-03-21

    Friction is an important issue that has to be carefully treated for the fabrication of graphene-based nano-scale devices. So far, the friction mechanism of graphene materials on the atomic scale has not yet been clearly presented. Here, first-principles calculations were employed to unveil the friction behaviors and their atomic-scale mechanism. We found that potential corrugations on sliding surfaces dominate the friction force and the friction anisotropy of graphene materials. Higher friction forces correspond to larger corrugations of potential energy, which are tuned by the number of graphene layers. The friction anisotropy is determined by the regular distributions of potential energy. The sliding along a fold-line path (hollow-atop-hollow) has a relatively small potential energy barrier. Thus, the linear sliding observed in macroscopic friction experiments may probably be attributed to the fold-line sliding mode on the atomic scale. These findings can also be extended to other layer-structure materials, such as molybdenum disulfide (MoS{sub 2}) and graphene-like BN sheets.

  12. Magnetic refrigeration apparatus with heat pipes

    DOEpatents

    Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)

    1987-01-01

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  13. Heat pipe power depending on its position

    NASA Astrophysics Data System (ADS)

    Mancikova, Veronika; Caja, Alexander; Malcho, Milan

    2014-08-01

    The heat pipe, also named two-phase thermo syphon, is utilized for heat transport. The gravity support is needed for condensate return of such heat pipe. The advantage of this heat pipe is that it can also workindifferenttiltangles compare to other heat pipes. The experimental measurements were carried out for the heat pipe at different tilt angles. In order to find out a dependence of performance on the position of the heat pipe were performed calculations. As a working fluid was used fluorinert FC 72.

  14. Magnetic refrigeration apparatus with heat pipes

    DOEpatents

    Barclay, J.A.; Prenger, F.C. Jr.

    1985-10-25

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe or pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  15. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, C.F.; Howard, B.D.

    1998-06-23

    A flexible, modular ultrasonic pipe inspection apparatus, comprises a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present. 7 figs.

  16. Centrally activated pipe snubbing system

    DOEpatents

    Cawley, William E. (Richland, WA)

    1985-01-01

    An electromechanical pipe snubbing system and an electromechanical pipe snubber. In the system, each pipe snubber, in a set of pipe snubbers, has an electromechanical mechanism to lock and unlock the snubber. A sensor, such as a seismometer, measures a quantity related to making a snubber locking or unlocking decision. A control device makes an electrical connection between a power supply and each snubber's electromechanical mechanism to simultaneously lock each snubber when the sensor measurement indicates a snubber locking condition. The control device breaks the connection to simultaneously unlock each snubber when the sensor measurement indicates a snubber unlocking condition. In the snubber, one end of the shaft slides within a bore in one end of a housing. The other end of the shaft is rotatably attached to a pipe; the other end of the housing is rotatively attached to a wall. The snubber's electromechanical mechanism locks the slidable end of the shaft to the housing and unlocks that end from the housing. The electromechanical mechanism permits remote testing and lockup status indication for each snubber.

  17. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, W.T.

    1992-06-16

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.

  18. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, William T. (3927 Almon Dr., Martinez, GA 30907)

    1992-01-01

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler.

  19. Superconducting pipes and levitating magnets

    E-print Network

    Levin, Y; Levin, Yan; Rizzato, Felipe B.

    2006-01-01

    Motivated by a beautiful demonstration of the Faraday's and Lenz's law in which a small neodymium magnet falls slowly through a conducting non-ferromagnetic tube, we consider the dynamics of a magnet falling through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be suspended over the front edge. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius $a$ and length $L \\approx a$ decays, in the axial direction, with a characteristic length $\\xi \\approx ...

  20. A Dual Resonant Microstrip Antenna for UHF RFID in the Cold Chain Using Corrugated Fiberboard as a Substrate

    E-print Network

    Sivakumar, Mutharasu

    2008-02-01

    and thus will help reducing food borne illness. Passive UHF RFID has been widely accepted to be a technology capable of increasing supply chain efficiency. Passive UHF RFID tags designed for supply chain application are tuned to work well on corrugated...

  1. Wet-sand impulse loading of metallic plates and corrugated core sandwich panels J.J. Rimoli a

    E-print Network

    Wadley, Haydn

    Wet-sand impulse loading of metallic plates and corrugated core sandwich panels J.J. Rimoli a , B the mechanical response of edge-clamped sandwich panels subject to the impact of explosively driven wet sand of wet sand placed at different standoff distances. Monolithic plates of the same alloy and mass per unit

  2. Two-phase friction pressure drop through corrugated tubes and quick-disconnect attachments in reduced gravity 

    E-print Network

    Marsden, Kenneth

    1996-01-01

    A two-phase flow experiment package was used to collect pressure drop data for corrugated flexible tubes and quick-disconnect attachments. Single-phase pressure drop measurements were taken on the ground and two-phase reduced gravity measurements...

  3. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  4. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  5. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  6. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  7. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  8. 46 CFR 154.512 - Piping: Thermal isolation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Shipping 5 2014-10-01 2014-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

  9. 46 CFR 154.512 - Piping: Thermal isolation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Shipping 5 2013-10-01 2013-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

  10. 46 CFR 154.512 - Piping: Thermal isolation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Shipping 5 2012-10-01 2012-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

  11. 46 CFR 154.512 - Piping: Thermal isolation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping 5 2010-10-01 2010-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

  12. 46 CFR 154.512 - Piping: Thermal isolation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Shipping 5 2011-10-01 2011-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

  13. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  14. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  15. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  16. 46 CFR 56.30-3 - Piping joints (reproduces 110).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56...APPURTENANCES Selection and Limitations of Piping Joints § 56.30-3 Piping joints (reproduces 110). The type of piping...

  17. Repair of filament wound composite pipes

    NASA Astrophysics Data System (ADS)

    Amali, Ramin; Arnall, Heather

    2015-07-01

    Filament wound pipes are used in a wide variety of industries, due to the advantages composites have over metal pipes, such as a high strength to weight ratio, and resistance against frost, corrosion and heat. Composite pipes require minimal maintenance to ensure they are safe. Any damage occurring in composite pipes could lead to failure; therefore all damage should be assessed through NDT. If it is decided that the damage makes the pipe unsafe then a decision needs to be made whether to repair or replace the pipe. Repairing a composite pipe can be quicker, easier and cheaper than replacing it and can restore the strength of the pipe effectively. This investigation looks at the repair process and the parameters involved in determining the strength of the pipe following repair through the use of over 150 models in FEA software, Abaqus. Parameters considered include the pipe diameter and thickness, damage removal size and wrap width and thickness. It was found that if the pipe is thin-walled then it can be assumed that the pipe's thickness has no effect on the FOS following repair. Formulas were created to predict the FOS following repair for varying pipe diameters, damage sizes and wrap thickness. Formulas were also created to determine the wrap width required for varying wrap thicknesses and damage sizes.

  18. Growth of InP directly on Si by corrugated epitaxial lateral overgrowth

    NASA Astrophysics Data System (ADS)

    Metaferia, Wondwosen; Kataria, Himanshu; Sun, Yan-Ting; Lourdudoss, Sebastian

    2015-02-01

    In an attempt to achieve an InP-Si heterointerface, a new and generic method, the corrugated epitaxial lateral overgrowth (CELOG) technique in a hydride vapor phase epitaxy reactor, was studied. An InP seed layer on Si (0?0?1) was patterned into closely spaced etched mesa stripes, revealing the Si surface in between them. The surface with the mesa stripes resembles a corrugated surface. The top and sidewalls of the mesa stripes were then covered by a SiO2 mask after which the line openings on top of the mesa stripes were patterned. Growth of InP was performed on this corrugated surface. It is shown that growth of InP emerges selectively from the openings and not on the exposed silicon surface, but gradually spreads laterally to create a direct interface with the silicon, hence the name CELOG. We study the growth behavior using growth parameters. The lateral growth is bounded by high index boundary planes of {3?3?1} and {2?1?1}. The atomic arrangement of these planes, crystallographic orientation dependent dopant incorporation and gas phase supersaturation are shown to affect the extent of lateral growth. A lateral to vertical growth rate ratio as large as 3.6 is achieved. X-ray diffraction studies confirm substantial crystalline quality improvement of the CELOG InP compared to the InP seed layer. Transmission electron microscopy studies reveal the formation of a direct InP-Si heterointerface by CELOG without threading dislocations. While CELOG is shown to avoid dislocations that could arise due to the large lattice mismatch (8%) between InP and Si, staking faults could be seen in the layer. These are probably created by the surface roughness of the Si surface or SiO2 mask which in turn would have been a consequence of the initial process treatments. The direct InP-Si heterointerface can find applications in high efficiency and cost-effective Si based III-V semiconductor multijunction solar cells and optoelectronics integration.

  19. Laboratory exercises on oscillation modes of pipes

    NASA Astrophysics Data System (ADS)

    Haeberli, Willy

    2009-03-01

    This paper describes an improved lab setup to study the vibrations of air columns in pipes. Features of the setup include transparent pipes which reveal the position of a movable microphone inside the pipe; excitation of pipe modes with a miniature microphone placed to allow access to the microphone stem for open, closed, or conical pipes; and sound insulation to avoid interference between different setups in a student lab. The suggested experiments on the modes of open, closed, and conical pipes, the transient response of a pipe, and the effect of pipe diameter are suitable for introductory physics laboratories, including laboratories for nonscience majors and music students, and for more advanced undergraduate laboratories. For honors students or for advanced laboratory exercises, the quantitative relation between the resonance width and damping time constant is of interest.

  20. 75 FR 877 - Drill Pipe From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-06

    ...Preliminary)] Drill Pipe From China AGENCY: International...retarded, by reason of imports from China of drill pipe, provided...by the Government of China. Unless the Department...Rubber, Manufacturing, Energy, Allied Industrial...

  1. 46 CFR 108.447 - Piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting in a CO2...

  2. High performance flexible heat pipes

    NASA Technical Reports Server (NTRS)

    Shaubach, R. M.; Gernert, N. J.

    1985-01-01

    A Phase I SBIR NASA program for developing and demonstrating high-performance flexible heat pipes for use in the thermal management of spacecraft is examined. The program combines several technologies such as flexible screen arteries and high-performance circumferential distribution wicks within an envelope which is flexible in the adiabatic heat transport zone. The first six months of work during which the Phase I contract goal were met, are described. Consideration is given to the heat-pipe performance requirements. A preliminary evaluation shows that the power requirement for Phase II of the program is 30.5 kilowatt meters at an operating temperature from 0 to 100 C.

  3. Cryogenic thermal diode heat pipes

    NASA Technical Reports Server (NTRS)

    Alario, J.

    1979-01-01

    The development of spiral artery cryogenic thermal diode heat pipes was continued. Ethane was the working fluid and stainless steel the heat pipe material in all cases. The major tasks included: (1) building a liquid blockage (blocking orifice) thermal diode suitable for the HEPP space flight experiment; (2) building a liquid trap thermal diode engineering model; (3) retesting the original liquid blockage engineering model, and (4) investigating the startup dynamics of artery cryogenic thermal diodes. An experimental investigation was also conducted into the wetting characteristics of ethane/stainless steel systems using a specially constructed chamber that permitted in situ observations.

  4. Introduction to Loop Heat Pipes

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Loop Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. This course will discuss operating principles and performance characteristics of a loop heat pipe. Topics include: 1) pressure profiles in the loop; 2) loop operating temperature; 3) operating temperature control; 4) loop startup; 4) loop shutdown; 5) loop transient behaviors; 6) sizing of loop components and determination of fluid inventory; 7) analytical modeling; 8) examples of flight applications; and 9) recent LHP developments.

  5. 46 CFR 61.15-5 - Steam piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Steam piping. 61.15-5 Section 61.15-5 Shipping COAST... Periodic Tests of Piping Systems § 61.15-5 Steam piping. (a) Main steam piping shall be subjected to a... removed and the piping thoroughly examined. (b) All steam piping subject to pressure from the main...

  6. 46 CFR 61.15-5 - Steam piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Steam piping. 61.15-5 Section 61.15-5 Shipping COAST... Periodic Tests of Piping Systems § 61.15-5 Steam piping. (a) Main steam piping shall be subjected to a... removed and the piping thoroughly examined. (b) All steam piping subject to pressure from the main...

  7. 46 CFR 61.15-5 - Steam piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Steam piping. 61.15-5 Section 61.15-5 Shipping COAST... Periodic Tests of Piping Systems § 61.15-5 Steam piping. (a) Main steam piping shall be subjected to a... removed and the piping thoroughly examined. (b) All steam piping subject to pressure from the main...

  8. 46 CFR 61.15-5 - Steam piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Steam piping. 61.15-5 Section 61.15-5 Shipping COAST... Periodic Tests of Piping Systems § 61.15-5 Steam piping. (a) Main steam piping shall be subjected to a... removed and the piping thoroughly examined. (b) All steam piping subject to pressure from the main...

  9. 46 CFR 61.15-5 - Steam piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Steam piping. 61.15-5 Section 61.15-5 Shipping COAST... Periodic Tests of Piping Systems § 61.15-5 Steam piping. (a) Main steam piping shall be subjected to a... removed and the piping thoroughly examined. (b) All steam piping subject to pressure from the main...

  10. 46 CFR 119.430 - Engine exhaust pipe installation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be properly supported by noncombustible hangers or blocks. (c) The exhaust piping must be so arranged as to... stresses resulting from the expansion of the exhaust piping. (g) A dry exhaust pipe must: (1) If it...

  11. 46 CFR 119.430 - Engine exhaust pipe installation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be properly supported by noncombustible hangers or blocks. (c) The exhaust piping must be so arranged as to... stresses resulting from the expansion of the exhaust piping. (g) A dry exhaust pipe must: (1) If it...

  12. 46 CFR 119.430 - Engine exhaust pipe installation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be properly supported by noncombustible hangers or blocks. (c) The exhaust piping must be so arranged as to... stresses resulting from the expansion of the exhaust piping. (g) A dry exhaust pipe must: (1) If it...

  13. 46 CFR 119.430 - Engine exhaust pipe installation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be properly supported by noncombustible hangers or blocks. (c) The exhaust piping must be so arranged as to... stresses resulting from the expansion of the exhaust piping. (g) A dry exhaust pipe must: (1) If it...

  14. Analysis thermal performance of capillary heat pipe

    NASA Astrophysics Data System (ADS)

    Kosa, Ľuboš; Nemec, Patrik; Malcho, Milan; Jobb, Marián

    2014-08-01

    This work is concentrated on the amount of working fluid for optimization thermal performance of capillary heat pipes. The main objective was to find ideal working fluid for horizontal working position for capillary heat pipes. Working position and amount of working fluid is an important part for function of the heat pipe. Change ideal amount working fluid should be change thermal performance capillary heat pipe.

  15. Dynamics of heat-pipe reactors

    NASA Technical Reports Server (NTRS)

    Niederauer, G. F.

    1971-01-01

    A split-core heat pipe reactor, fueled with either U(233)C or U(235)C in a tungsten cermet and cooled by 7-Li-W heat pipes, was examined for the effects of the heat pipes on reactor while trying to safely absorb large reactivity inputs through inherent shutdown mechanisms. Limits on ramp reactivity inputs due to fuel melting temperature and heat pipe wall heat flux were mapped for the reactor in both startup and at-power operating modes.

  16. Surface Plasmon-Polariton Mediated Red Emission from Organic Light-Emitting Devices Based on Metallic Electrodes Integrated with Dual-Periodic Corrugation

    PubMed Central

    Bi, Yan-Gang; Feng, Jing; Liu, Yu-Shan; Li, Yun-Fei; Chen, Yang; Zhang, Xu-Lin; Han, Xiao-Chi; Sun, Hong-Bo

    2014-01-01

    We demonstrate an effective approach to realize excitation and outcoupling of the SPP modes associated with both cathode/organic and anode/organic interfaces in OLEDs by integrating dual-periodic corrugation. The dual-periodic corrugation consists of two set gratings with different periods. The light trapped in the SPP modes associated with both top and bottom electrode/organic interfaces are efficiently extracted from the OLEDs by adjusting appropriate periods of two set corrugations, and a 29% enhancement in the current efficiency has been obtained. PMID:25407776

  17. Thermal Performance of High Temperature Titanium-Water Heat Pipes by Multiple Heat Pipe Manufacturers

    NASA Technical Reports Server (NTRS)

    Sanzi, James L.

    2007-01-01

    Titanium-water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

  18. Thermal Performance of High Temperature Titanium - Water Heat Pipes by Multiple Heat Pipe Manufacturers

    NASA Astrophysics Data System (ADS)

    Sanzi, James L.

    2007-01-01

    Titanium - water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity aided, in the horizontal position and elevations against gravity at 450 K and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

  19. Thermal Performance of High Temperature Titanium -- Water Heat Pipes by Multiple Heat Pipe Manufacturers

    NASA Technical Reports Server (NTRS)

    Sanzi, James L.

    2007-01-01

    Titanium - water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 K and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

  20. Macroscopic Ordering of Block Copolymers into Sequenced Patterns on Topographically Corrugated Surface

    NASA Astrophysics Data System (ADS)

    Park, Sungjune; Tsarkova, Larisa; Hiltl, Stephanie; Roitsch, Stefan; Mayer, Joachim; Böker, Alexander

    2012-02-01

    For the guided block copolymer assembly we used corrugated SiCN ceramic substrates which were fabricated by a facile replication process using non-lithographic PDMS masters. During thermal annealing of polystyrene-b-polybutadiene diblock copolymer, the material transport was guided by the wrinkled substrate to form regular modulations in the film thickness. As a consequence of the thickness-dependent morphological behavior of block copolymers, the film surface appears as sequenced patterns of alternative microphase separated structures. The ordering process is attributed to the formation of reverse terraces which match the substrate topography, so that the resulting surface patterns are free from the surface relief structures within macroscopically-large areas. The issues of the film thickness, the substrate surface energy and the pattern geometry are addressed. Our approach demonstrates an effective synergism of external confinement and internal polymorphism of block copolymers towards complex hierarchically-structured patterned surfaces.

  1. Interferometric investigations of convection in slat, flat plate and vee-corrugated solar collectors

    NASA Astrophysics Data System (ADS)

    Meyer, B. A.; Randall, K. R.; El-Wakil, M. M.; Mitchell, J. W.

    An interferometric study is presented which determined the local and average values of the Nusselt number in moderate and small aspect ratio flat-plate enclosures. The investigation was made of collector tilt angles from 45 to 90 deg, aspect ratios from .25 to 36 and slat angles from 45 to 90 deg. The results show that aspect ratios between .5 and 10 are undesirable because of a convective loss; collector geometries with slat angles less than 90 deg are effective in reducing convective losses. Heat transfer rates in an enclosure bounded by a heated vee-corrugated surface on the bottom and a cooled flat surface on the top were also examined for vee aspect ratios of .75, 1, and 2 and tilt angles of 0, 45, and 60 deg. It is concluded that the average heat transfer for this geometry is considerably higher than for the flat-plate collector operating under similar conditions.

  2. TE(01) mode propagation at wavelength = 394 microns in smooth and corrugated circular metallic waveguides

    NASA Astrophysics Data System (ADS)

    Marhic, M. E.; Spektor, D.

    1983-09-01

    The attenuation of the TE(01) mode in straight circular metallic waveguides has been measured at wavelength = 394 microns. The radiation was produced by an optically-pumped HCOOH waveguide laser, with i.d. as small as 4 mm. The losses were measured in smooth waveguides as well as in guides with a fine helical corrugation on the inner wall, designed to reduce the detrimental TE(01)-TM(11) coupling. The losses in both types of guides were substantial, being, respectively, of the order of 30 and 60 percent per meter, for 4.8 mm i.d. tubes; this is more than an order of magnitude larger than the theoretically expected values.

  3. Characterization of Mechanical Properties of Aluminum Processed by Repetitive Corrugation and Straightening Process using Taguchi Analysis

    NASA Astrophysics Data System (ADS)

    Siddesha, H. S.; Shantharaja, M.

    2013-02-01

    The severe plastic deformation process is capable of developing the submicron grain structures in metallic alloys and to improve the mechanical properties. Repetitive corrugation and straightening (RCS) processes are widely used in industries to compensate the high-strength metal plates components used in automobiles. In this work, an attempt has been made to study the influence of RCS parameters like strain rate, number of passes, and plate thickness to produce grain refinement in metallic alloys. Experiments were based on the Taguchi method and the analysis of variance (ANOVA) technique was an effective tool to predict the degree of importance of the RCS parameters on grain size, microhardness, and tensile strength of RCS specimens. The results indicated that the number of passes has a major influence on the fine-grain refinement, followed by Al plate thickness and strain rate.

  4. Implementation of the CMOS MEMS Condenser Microphone with Corrugated Metal Diaphragm and Silicon Back-Plate

    PubMed Central

    Huang, Chien-Hsin; Lee, Chien-Hsing; Hsieh, Tsung-Min; Tsao, Li-Chi; Wu, Shaoyi; Liou, Jhyy-Cheng; Wang, Ming-Yi; Chen, Li-Che; Yip, Ming-Chuen; Fang, Weileun

    2011-01-01

    This study reports a CMOS-MEMS condenser microphone implemented using the standard thin film stacking of 0.35 ?m UMC CMOS 3.3/5.0 V logic process, and followed by post-CMOS micromachining steps without introducing any special materials. The corrugated diaphragm for the microphone is designed and implemented using the metal layer to reduce the influence of thin film residual stresses. Moreover, a silicon substrate is employed to increase the stiffness of the back-plate. Measurements show the sensitivity of microphone is ?42 ± 3 dBV/Pa at 1 kHz (the reference sound-level is 94 dB) under 6 V pumping voltage, the frequency response is 100 Hz–10 kHz, and the S/N ratio >55 dB. It also has low power consumption of less than 200 ?A, and low distortion of less than 1% (referred to 100 dB). PMID:22163953

  5. Radial Corrugations of Multi-Walled Carbon Nanotubes Driven by Inter-Wall Nonbonding Interactions

    PubMed Central

    2011-01-01

    We perform large-scale quasi-continuum simulations to determine the stable cross-sectional configurations of free-standing multi-walled carbon nanotubes (MWCNTs). We show that at an inter-wall spacing larger than the equilibrium distance set by the inter-wall van der Waals (vdW) interactions, the initial circular cross-sections of the MWCNTs are transformed into symmetric polygonal shapes or asymmetric water-drop-like shapes. Our simulations also show that removing several innermost walls causes even more drastic cross-sectional polygonization of the MWCNTs. The predicted cross-sectional configurations agree with prior experimental observations. We attribute the radial corrugations to the compressive stresses induced by the excessive inter-wall vdW energy release of the MWCNTs. The stable cross-sectional configurations provide fundamental guidance to the design of single MWCNT-based devices and shed lights on the mechanical control of electrical properties.

  6. Energy shift of collective electron excitations in highly corrugated graphitic nanostructures: Experimental and theoretical investigation

    SciTech Connect

    Sedelnikova, O. V. Bulusheva, L. G.; Okotrub, A. V.; Asanov, I. P.; Yushina, I. V.

    2014-04-21

    Effect of corrugation of hexagonal carbon network on the collective electron excitations has been studied using optical absorption and X-ray photoelectron spectroscopy in conjunction with density functional theory calculations. Onion-like carbon (OLC) was taken as a material, where graphitic mantle enveloping agglomerates of multi-shell fullerenes is strongly curved. Experiments showed that positions of ? and ??+?? plasmon modes as well as ? ? ?* absorption peak are substantially redshifted for OLC as compared with those of highly ordered pyrolytic graphite and thermally exfoliated graphite consisted of planar sheets. This effect was reproduced in behavior of dielectric functions of rippled graphite models calculated within the random phase approximation. We conclude that the energy of electron excitations in graphitic materials could be precisely tuned by a simple bending of hexagonal network without change of topology. Moreover, our investigation suggests that in such materials optical exciton can transfer energy to plasmon non-radiatively.

  7. Highly tapered pentagonal bipyramidal Au microcrystals with high index faceted corrugation: Synthesis and optical properties

    PubMed Central

    Mettela, Gangaiah; Boya, Radha; Singh, Danveer; Kumar, G. V. Pavan; Kulkarni, G. U.

    2013-01-01

    Focusing light at sub-wavelength region opens up interesting applications in optical sensing and imaging beyond the diffraction limit. In the past, tapered Au wires with carved gratings have been employed to achieve nanofocusing. The fabrication process however, is expensive and the obtained wires are polycrystalline with high surface roughness. A chemical synthetic method overcoming these hurdles should be an attractive alternative. Here, we report a method to chemically synthesize Au microcrystals (~10??m) bearing pentagonal bipyramidal morphology with surface corrugations assignable to high index planes. The method is a single step solid state synthesis at a temperature amenable to common substrates. The microcrystals are tapered at both ends forming sharp tips (~55?nm). Individual microcrystals have been used as pick and probe SERS substrates for a dye embedded in a polymer matrix. The unique geometry of the microcrystal also enables light propagation across its length.

  8. Dynamical back-action at 5.5 GHz in a corrugated optomechanical beam

    SciTech Connect

    Navarro-Urrios, D.; Gomis-Bresco, J.; Alzina, F.; El-Jallal, S.; Oudich, M.; Pennec, Y.; Djafari-Rouhani, B.; Pitanti, A.; Capuj, N.; Tredicucci, A.; Griol, A.; Martínez, A.; Sotomayor Torres, C. M.

    2014-12-15

    We report on the optomechanical properties of a breathing mechanical mode oscillating at 5.5 GHz in a 1D corrugated Si nanobeam. This mode has an experimental single-particle optomechanical coupling rate of |g{sub o,OM}| = 1.8 MHz (|g{sub o,OM}|/2? = 0.3 MHz) and shows strong dynamical back-action effects at room temperature. The geometrical flexibility of the unit-cell would lend itself to further engineering of the cavity region to localize the mode within the full phononic band-gap present at 4 GHz while keeping high g{sub o,OM} values. This would lead to longer lifetimes at cryogenic temperatures, due to the suppression of acoustic leakage.

  9. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic...

  10. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic...

  11. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic...

  12. 14 CFR 29.1123 - Exhaust piping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 29.1123 Section 29.1123... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust... by operating temperatures. (b) Exhaust piping must be supported to withstand any vibration...

  13. 14 CFR 25.1123 - Exhaust piping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 25.1123 Section 25.1123... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Exhaust System § 25.1123 Exhaust piping. For powerplant and auxiliary power unit installations, the following apply: (a) Exhaust piping must be heat...

  14. 46 CFR 119.455 - Fuel piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Fuel piping. 119.455 Section 119.455 Shipping COAST... Machinery Requirements § 119.455 Fuel piping. (a) Materials and workmanship. The materials and construction of fuel lines, including pipe, tube, and hose, must comply with the requirements of this...

  15. 46 CFR 119.455 - Fuel piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Fuel piping. 119.455 Section 119.455 Shipping COAST... Machinery Requirements § 119.455 Fuel piping. (a) Materials and workmanship. The materials and construction of fuel lines, including pipe, tube, and hose, must comply with the requirements of this...

  16. 46 CFR 119.455 - Fuel piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Fuel piping. 119.455 Section 119.455 Shipping COAST... Machinery Requirements § 119.455 Fuel piping. (a) Materials and workmanship. The materials and construction of fuel lines, including pipe, tube, and hose, must comply with the requirements of this...

  17. 46 CFR 108.447 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Piping. 108.447 Section 108.447 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting in a CO2 system must have...

  18. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Piping. 108.475 Section 108.475 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Foam Extinguishing Systems § 108.475 Piping. (a) Each pipe, valve, and fitting in a foam extinguishing system must meet...

  19. 46 CFR 64.33 - Pipe connection.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping 2 2010-10-01 2010-10-01 false Pipe connection. 64.33 Section 64.33 Shipping...HANDLING SYSTEMS Standards for an MPT § 64.33 Pipe connection. Each pipe connection that is not a pressure relief device...

  20. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 3 2011-10-01 2011-10-01 false New pipe. 195.112 Section 195.112 Transportation...BY PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must comply with...

  1. 46 CFR 64.33 - Pipe connection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Shipping 2 2011-10-01 2011-10-01 false Pipe connection. 64.33 Section 64.33 Shipping...HANDLING SYSTEMS Standards for an MPT § 64.33 Pipe connection. Each pipe connection that is not a pressure relief device...

  2. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 3 2010-10-01 2010-10-01 false New pipe. 195.112 Section 195.112 Transportation...BY PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must comply with...

  3. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2 2010-10-01 2010-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST...LINES Conditions of Assignment § 45.133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or...

  4. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping 5 2010-10-01 2010-10-01 false Pipe welding. 154.660 Section 154.660 Shipping...Construction and Equipment Construction § 154.660 Pipe welding. (a) Pipe welding must meet Part 57 of this chapter....

  5. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Shipping 5 2011-10-01 2011-10-01 false Pipe welding. 154.660 Section 154.660 Shipping...Construction and Equipment Construction § 154.660 Pipe welding. (a) Pipe welding must meet Part 57 of this chapter....

  6. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2 2011-10-01 2011-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST...LINES Conditions of Assignment § 45.133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or...

  7. 46 CFR 119.455 - Fuel piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Fuel piping. 119.455 Section 119.455 Shipping COAST... Machinery Requirements § 119.455 Fuel piping. (a) Materials and workmanship. The materials and construction of fuel lines, including pipe, tube, and hose, must comply with the requirements of this...

  8. 46 CFR 119.455 - Fuel piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Fuel piping. 119.455 Section 119.455 Shipping COAST... Machinery Requirements § 119.455 Fuel piping. (a) Materials and workmanship. The materials and construction of fuel lines, including pipe, tube, and hose, must comply with the requirements of this...

  9. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false New pipe. 195.112 Section 195.112 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must...

  10. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false New pipe. 195.112 Section 195.112 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must...

  11. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false New pipe. 195.112 Section 195.112 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must...

  12. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false New pipe. 195.112 Section 195.112 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must...

  13. 49 CFR 195.112 - New pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false New pipe. 195.112 Section 195.112 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.112 New pipe. Any new pipe installed in a pipeline system must...

  14. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion... miter joint. (b) Solvent cement joints. Each solvent cement joint on plastic pipe must comply with the... detrimental to the joint. (2) The solvent cement must conform to ASTM D2513-99, (incorporated by...

  15. FIELD STUDIES OF IMPREGNATED CONCRETE PIPE

    EPA Science Inventory

    The follow-on study (initiated in June 1980) continued to monitor performance of 1,400 ft of impregnated concrete pipe installed in several Texas cities. The performance of concrete pipe has been compared with that of sulfur-impregnated concrete pipe; hydrofluoric acid (HF)-treat...

  16. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Transportation 3 2014-10-01 2014-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding § 192.279 Copper pipe. Copper pipe may not be threaded except that copper...

  17. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Transportation 3 2013-10-01 2013-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding § 192.279 Copper pipe. Copper pipe may not be threaded except that copper...

  18. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Transportation 3 2012-10-01 2012-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding § 192.279 Copper pipe. Copper pipe may not be threaded except that copper...

  19. The locating ways of laying pipe manipulator

    NASA Astrophysics Data System (ADS)

    Wang, Dan; Li, Bin; Lei, DongLiang

    2010-01-01

    The laying pipe manipulator is a new equipment to lay concrete pipe. This kind of manipulator makes the work of laying pipes mechanized and automated. We report here a new laying pipe manipulator. The manipulator has 5 free degrees, and is driven by the hydraulic system. In the paper, one critical question of manipulator is studied: the locating ways of the manipulator to lay concrete pipe. During the process of laying concrete pipe, how to locate the manipulator is realized by the locating system of manipulator. The locating system consists of photoelectric target, laser producer, and computer. According to different construction condition, one or two or three photoelectric targets can be used. During the process of laying concrete pipe, if the interface of pipes are jointed together, and the other segment of pipe deviates from the pipe way, one target can be used, if the angle that the manipulator rotates around the holding pipe's axes is 0°, two targets can be used, three targets can be used at any site. In the paper, according to each locating way, the theory analysis is done. And the mathematical models of the manipulator moving from original position to goal position are obtained by different locating way. And the locating experiment was done. According to the experiment result, the work principle and mathematical models of different locating way was turned out to be well adopted for requirement, the mathematical model of different locating way supplies the basic control theory for the manipulator to lay and joint concrete pipe automatically.

  20. The locating ways of laying pipe manipulator

    NASA Astrophysics Data System (ADS)

    Wang, Dan; Li, Bin; Lei, Dongliang

    2009-12-01

    The laying pipe manipulator is a new equipment to lay concrete pipe. This kind of manipulator makes the work of laying pipes mechanized and automated. We report here a new laying pipe manipulator. The manipulator has 5 free degrees, and is driven by the hydraulic system. In the paper, one critical question of manipulator is studied: the locating ways of the manipulator to lay concrete pipe. During the process of laying concrete pipe, how to locate the manipulator is realized by the locating system of manipulator. The locating system consists of photoelectric target, laser producer, and computer. According to different construction condition, one or two or three photoelectric targets can be used. During the process of laying concrete pipe, if the interface of pipes are jointed together, and the other segment of pipe deviates from the pipe way, one target can be used, if the angle that the manipulator rotates around the holding pipe's axes is 0°, two targets can be used, three targets can be used at any site. In the paper, according to each locating way, the theory analysis is done. And the mathematical models of the manipulator moving from original position to goal position are obtained by different locating way. And the locating experiment was done. According to the experiment result, the work principle and mathematical models of different locating way was turned out to be well adopted for requirement, the mathematical model of different locating way supplies the basic control theory for the manipulator to lay and joint concrete pipe automatically.

  1. 46 CFR 76.10-15 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Piping. 76.10-15 Section 76.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 76.10-15 Piping. (a) All piping, valves, and fittings shall meet the applicable requirements of subchapter F (Marine Engineering)...

  2. 46 CFR 193.10-15 - Piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Piping. 193.10-15 Section 193.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-15 Piping. (a) All piping, valves, and fittings, shall meet the applicable requirements of Subchapter F...

  3. 46 CFR 193.10-15 - Piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Piping. 193.10-15 Section 193.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-15 Piping. (a) All piping, valves, and fittings, shall meet the applicable requirements of Subchapter F...

  4. 46 CFR 95.10-15 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Piping. 95.10-15 Section 95.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 95.10-15 Piping. (a) All piping, valves, and fittings shall meet the applicable requirements of subchapter F...

  5. 46 CFR 193.10-15 - Piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Piping. 193.10-15 Section 193.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-15 Piping. (a) All piping, valves, and fittings, shall meet the applicable requirements of Subchapter F...

  6. 46 CFR 76.17-15 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Piping. 76.17-15 Section 76.17-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Foam Extinguishing Systems, Details § 76.17-15 Piping. (a) All piping, valves, and fittings shall meet the applicable requirements of subchapter F...

  7. Bag Test Measures Leakage From Insulated Pipe

    NASA Technical Reports Server (NTRS)

    Schock, Kent D.; Easter, Barry P.

    1994-01-01

    Test quantifies leakage of gas from pipe even though pipe covered with insulation. Involves use of helium analyzer to measure concentration of helium in impermeable bag around pipe. Test administered after standard soap-solution bubble test indicates presence and general class of leakage.

  8. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Pipe welding. 154.660 Section 154.660 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.660 Pipe welding. (a) Pipe welding must meet Part 57 of this chapter. (b) Longitudinal butt...

  9. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Pipe welding. 154.660 Section 154.660 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.660 Pipe welding. (a) Pipe welding must meet part 57 of this chapter. (b) Longitudinal butt...

  10. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Pipe welding. 154.660 Section 154.660 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.660 Pipe welding. (a) Pipe welding must meet part 57 of this chapter. (b) Longitudinal butt...

  11. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Pipe welding. 154.660 Section 154.660 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.660 Pipe welding. (a) Pipe welding must meet part 57 of this chapter. (b) Longitudinal butt...

  12. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pipe welding. 154.660 Section 154.660 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.660 Pipe welding. (a) Pipe welding must meet Part 57 of this chapter. (b) Longitudinal butt...

  13. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Pressure piping. 197.336 Section 197.336 Shipping COAST... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems that are not an integral part of the vessel or facility, carrying fluids under pressures exceeding 15...

  14. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Pressure piping. 197.336 Section 197.336 Shipping COAST... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems that are not an integral part of the vessel or facility, carrying fluids under pressures exceeding 15...

  15. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Pressure piping. 197.336 Section 197.336 Shipping COAST... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems that are not an integral part of the vessel or facility, carrying fluids under pressures exceeding 15...

  16. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Pressure piping. 197.336 Section 197.336 Shipping COAST... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.336 Pressure piping. Piping systems that are not an integral part of the vessel or facility, carrying fluids under pressures exceeding 15...

  17. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion..., see § 192.7). (3) The joint may not be heated to accelerate the setting of the cement. (c) Heat-fusion joints. Each heat-fusion joint on plastic pipe must comply with the following: (1) A butt...

  18. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion..., see § 192.7). (3) The joint may not be heated to accelerate the setting of the cement. (c) Heat-fusion joints. Each heat-fusion joint on plastic pipe must comply with the following: (1) A butt...

  19. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion..., see § 192.7). (3) The joint may not be heated to accelerate the setting of the cement. (c) Heat-fusion joints. Each heat-fusion joint on plastic pipe must comply with the following: (1) A butt...

  20. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion..., see § 192.7). (3) The joint may not be heated to accelerate the setting of the cement. (c) Heat-fusion joints. Each heat-fusion joint on plastic pipe must comply with the following: (1) A butt...

  1. 46 CFR 193.15-15 - Piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Piping. 193.15-15 Section 193.15-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-15 Piping. (a) The piping, valves, and fittings shall have a...

  2. 46 CFR 108.447 - Piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Piping. 108.447 Section 108.447 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe,...

  3. 46 CFR 193.15-15 - Piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Piping. 193.15-15 Section 193.15-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-15 Piping. (a) The piping, valves, and fittings shall have a bursting pressure of not...

  4. 46 CFR 193.15-15 - Piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... carbon dioxide or other inert gas shall be used for this test. (2) The piping from the cylinders to the..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-15 Piping. (a) The piping, valves,...

  5. 46 CFR 95.15-15 - Piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Piping. 95.15-15 Section 95.15-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-15 Piping. (a) The piping, valves, and fittings shall have a bursting pressure of not...

  6. 46 CFR 108.447 - Piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Piping. 108.447 Section 108.447 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting in a CO2 system must have...

  7. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic...

  8. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic...

  9. Thermodynamic aspects of heat pipe operation

    NASA Technical Reports Server (NTRS)

    Richter, Robert; Gottschlich, Joseph

    1990-01-01

    An expanded heat pipe operating model is described which includes thermodynamic and heat transfer considerations to reconcile disparities between actual and theoretical heat pipe performances. The analysis shows that thermodynamic considerations can explain the observed heat pipe performance limitations. A full understanding of thermodynamic processes could lead to advanced concepts for thermal transport devices.

  10. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...3 2010-10-01 2010-10-01 false Plastic pipe. 192.281 Section 192.281 Transportation...Materials Other Than by Welding § 192.281 Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent...

  11. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 3 2012-10-01 2012-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...

  12. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...3 2012-10-01 2012-10-01 false Plastic pipe. 192.281 Section 192.281 Transportation...Materials Other Than by Welding § 192.281 Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent...

  13. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...3 2013-10-01 2013-10-01 false Plastic pipe. 192.281 Section 192.281 Transportation...Materials Other Than by Welding § 192.281 Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent...

  14. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 3 2013-10-01 2013-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...

  15. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...3 2014-10-01 2014-10-01 false Plastic pipe. 192.281 Section 192.281 Transportation...Materials Other Than by Welding § 192.281 Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent...

  16. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 3 2010-10-01 2010-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...

  17. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 3 2014-10-01 2014-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...

  18. 49 CFR 192.59 - Plastic pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 3 2011-10-01 2011-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...

  19. 49 CFR 192.281 - Plastic pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...3 2011-10-01 2011-10-01 false Plastic pipe. 192.281 Section 192.281 Transportation...Materials Other Than by Welding § 192.281 Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent...

  20. Pipe Leak Detection Technology Development

    EPA Science Inventory

    The U. S. Environmental Protection Agency (EPA) has determined that one of the nation’s biggest infrastructural needs is the replacement or rehabilitation of the water distribution and transmission systems. The institution of more effective pipe leak detection technology will im...