Sample records for tank liner life

  1. Lifecycle Verification of Tank Liner Polymers

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

    Anovitz, Lawrence; Smith, Barton

    2014-03-01

    This report describes a method that was developed for the purpose of assessing the durability of thermoplastic liners used in a Type IV hydrogen storage tank during the tank s expected service life. In the method, a thermoplastic liner specimen is cycled between the maximum and minimum expected working temperatures while it is differentially pressurized with high-pressure hydrogen gas. The number of thermal cycling intervals corresponds to those expected within the tank s design lifetime. At prescribed intervals, hydrogen permeation measurements are done in situ to assess the ability of the liner specimen to maintain its hydrogen barrier properties andmore » to model its permeability over the tank lifetime. Finally, the model is used to assess whether the steady-state leakage rate in the tank could potentially exceed the leakage specification for hydrogen fuel cell passenger vehicles. A durability assessment was performed on a specimen of high-density polyethylene (HDPE) that is in current use as a tank liner. Hydrogen permeation measurements were performed on several additional tank liner polymers as well as novel polymers proposed for use as storage tank liners and hydrogen barrier materials. The following technical barriers from the Fuel Cell Technologies Program MYRDD were addressed by the project: D. Durability of on-board storage systems lifetime of at least 1500 cycles G. Materials of construction vessel containment that is resistant to hydrogen permeation M. Lack of Tank Performance Data and Understanding of Failure Mechanisms And the following technical targets1 for on-board hydrogen storage systems R&D were likewise addressed: Operational cycle life (1/4 tank to full) FY 2017: 1500 cycles; Ultimate: 1500 cycles Environmental health & safety Permeation and leakage: Meets or exceeds applicable standards Loss of useable H2: FY 2017: 0.05 g/h/kg H2; Ultimate: 0.05 g/h/kg H2« less

  2. Fracture control method for composite tanks with load sharing liners

    NASA Technical Reports Server (NTRS)

    Bixler, W. D.

    1975-01-01

    The experimental program was based on the premise that the plastic sizing cycle, which each pressure vessel is subjected to prior to operation, acts as an effective proof test of the liner, screening out all flaws or cracks larger than a critical size. In doing so, flaw growth potential is available for cyclic operation at pressures less than the sizing pressure. Static fracture and cyclic life tests, involving laboratory type specimens and filament overwrapped tanks, were conducted on three liner materials: (1) 2219-T62 aluminum, (2) Inconel X750 STA, and (3) cryoformed 301 stainless steel. Variables included material condition, thickness, flaw size, flaw shape, temperature, sizing stress level, operating stress level and minimum-to-maximum operating stress ratio. From the empirical data base obtained, a procedure was established by which the service life of composite tanks with load sharing liners could be guaranteed with a high degree of confidence.

  3. Thermographic inspection of pipes, tanks, and containment liners

    NASA Astrophysics Data System (ADS)

    Renshaw, Jeremy B.; Lhota, James R.; Muthu, Nathan; Shepard, Steven M.

    2015-03-01

    Nuclear power plants are required to operate at a high level of safety. Recent industry and license renewal commitments aim to further increase safety by requiring the inspection of components that have not traditionally undergone detailed inspected in the past, such as tanks and liners. NEI 09-14 requires the inspection of buried pipes and tanks while containment liner inspections are required as a part of license renewal commitments. Containment liner inspections must inspect the carbon steel liner for defects - such as corrosion - that could threaten the pressure boundary and ideally, should be able to inspect the surrounding concrete for foreign material that could be in contact with the steel liner and potentially initiate corrosion. Such an inspection requires a simultaneous evaluation of two materials with very different material properties. Rapid, yet detailed, inspection results are required due to the massive size of the tanks and containment liners to be inspected. For this reason, thermal NDE methods were evaluated to inspect tank and containment liner mockups with simulated defects. Thermographic Signal Reconstruction (TSR) was utilized to enhance the images and provide detailed information on the sizes and shapes of the observed defects. The results show that thermographic inspection is highly sensitive to the defects of interest and is capable of rapidly inspecting large areas.

  4. Thermographic inspection of pipes, tanks, and containment liners

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

    Renshaw, Jeremy B., E-mail: jrenshaw@epri.com; Muthu, Nathan; Lhota, James R.

    2015-03-31

    Nuclear power plants are required to operate at a high level of safety. Recent industry and license renewal commitments aim to further increase safety by requiring the inspection of components that have not traditionally undergone detailed inspected in the past, such as tanks and liners. NEI 09-14 requires the inspection of buried pipes and tanks while containment liner inspections are required as a part of license renewal commitments. Containment liner inspections must inspect the carbon steel liner for defects - such as corrosion - that could threaten the pressure boundary and ideally, should be able to inspect the surrounding concretemore » for foreign material that could be in contact with the steel liner and potentially initiate corrosion. Such an inspection requires a simultaneous evaluation of two materials with very different material properties. Rapid, yet detailed, inspection results are required due to the massive size of the tanks and containment liners to be inspected. For this reason, thermal NDE methods were evaluated to inspect tank and containment liner mockups with simulated defects. Thermographic Signal Reconstruction (TSR) was utilized to enhance the images and provide detailed information on the sizes and shapes of the observed defects. The results show that thermographic inspection is highly sensitive to the defects of interest and is capable of rapidly inspecting large areas.« less

  5. Composite-Material Tanks with Chemically Resistant Liners

    NASA Technical Reports Server (NTRS)

    DeLay, Thomas K.

    2004-01-01

    Lightweight composite-material tanks with chemically resistant liners have been developed for storage of chemically reactive and/or unstable fluids . especially hydrogen peroxide. These tanks are similar, in some respects, to the ones described in gLightweight Composite-Material Tanks for Cryogenic Liquids h (MFS-31379), NASA Tech Briefs, Vol. 25, No. 1 (January, 2001), page 58; however, the present tanks are fabricated by a different procedure and they do not incorporate insulation that would be needed to prevent boil-off of cryogenic fluids. The manufacture of a tank of this type begins with the fabrication of a reusable multisegmented aluminum mandrel in the shape and size of the desired interior volume. One or more segments of the mandrel can be aluminum bosses that will be incorporated into the tank as end fittings. The mandrel is coated with a mold-release material. The mandrel is then heated to a temperature of about 400 F (approximately equal to 200 C) and coated with a thermoplastic liner material to the desired thickness [typically approxiamtely equal to 15 mils (approximately equal to 0.38 mm)] by thermal spraying. In the thermal-spraying process, the liner material in powder form is sprayed and heated to the melting temperature by a propane torch and the molten particles land on the mandrel. The sprayed liner and mandrel are allowed to cool, then the outer surface of the liner is chemically and/or mechanically etched to enhance bonding of a composite overwrap. The etched liner is wrapped with multiple layers of an epoxy resin reinforced with graphite fibers; the wrapping can be done either by manual application of epoxy-impregnated graphite cloth or by winding of epoxy-impregnated filaments. The entire assembly is heated in an autoclave to cure the epoxy. After the curing process, the multisegmented mandrel is disassembled and removed from inside, leaving the finished tank. If the tank is to be used for storing hydrogen peroxide, then the liner material

  6. Liner-less Tanks for Space Application - Design and Manufacturing Considerations

    NASA Technical Reports Server (NTRS)

    Jones, Brian H.; Li, Min-Chung

    2003-01-01

    Composite pressure vessels, used extensively for gas and fuel containment in space vehicles, are generally constructed with a metallic liner, while the fiber reinforcement carries the major portion of the pressure-induced load. The design is dominated by the liner s low strain at yield since the reinforcing fibers cannot operate at their potential load-bearing capability without resorting to pre-stressing (or autofrettaging). An ultra high-efficiency pressure vessel, which operates at the optimum strain capability of the fibers, can be potentially achieved with a liner-less construction. This paper discusses the design and manufacturing challenges to be overcome in the development of such a pressure vessel. These include: (1) gas/liquid containment and permeation, (2) design and structural analysis, and (3) manufacturing process development. The paper also presents the development and validation tests on a liner-less pressure vessel developed by Kaiser Compositek Inc. (KCI). It should be noted that KCI s liner-less tank exhibits a highly controlled leak-before-burst mode. This feature results in a structure having the highest level of safety.

  7. Expert Panel Recommendations for Hanford Double-Shell Tank Life Extension

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

    Stewart, Charles W; Bush, Spencer H; Berman, Herbert Stanton

    2001-06-29

    Expert workshops were held in Richland in May 2001 to review the Hanford Double-Shell Tank Integrity Project and make recommendations to extend the life of Hanford's double-shell waste tanks. The workshop scope was limited to corrosion of the primary tank liner, and the main areas for review were waste chemistry control, tank inspection, and corrosion monitoring. Participants were corrosion experts from Hanford, Savannah River Site, Brookhaven National Lab., Pacific Northwest National Lab., and several consultants. This report describes the current state of the three areas of the program, the final recommendations of the workshop, and the rationale for their selection.

  8. Tank 241-AY-102 Secondary Liner Corrosion Evaluation - 14191

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

    Boomer, Kayle D.; Washenfelder, Dennis J.; Johnson, Jeremy M.

    2014-01-07

    In October 2012, Washington River Protection Solutions, LLC (WRPS) determined that the primary tank of 241-AY-102 (AY-102) was leaking. A number of evaluations were performed after discovery of the leak which identified corrosion from storage of waste at the high waste temperatures as one of the major contributing factors in the failure of the tank. The propensity for corrosion of the waste on the annulus floor will be investigated to determine if it is corrosive and must be promptly removed or if it is benign and may remain in the annulus. The chemical composition of waste, the temperature and themore » character of the steel are important factors in assessing the propensity for corrosion. Unfortunately, the temperatures of the wastes in contact with the secondary steel liner are not known; they are estimated to range from 45 deg C to 60 deg C. It is also notable that most corrosion tests have been carried out with un-welded, stress-relieved steels, but the secondary liner in tank AY-102 was not stress-relieved. In addition, the cold weather fabrication and welding led to many problems, which required repeated softening of the metal to flatten secondary bottom during its construction. This flame treatment may have altered the microstructure of the steel.« less

  9. LITERATURE REVIEW ON THE SORPTION OF PLUTONIUM, URANIUM, NEPTUNIUM, AMERICIUM AND TECHNETIUM TO CORROSION PRODUCTS ON WASTE TANK LINERS

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

    Li, D.; Kaplan, D.

    2012-02-29

    The Savannah River Site (SRS) has conducted performance assessment (PA) calculations to determine the risk associated with closing liquid waste tanks. The PA estimates the risk associated with a number of scenarios, making various assumptions. Throughout all of these scenarios, it is assumed that the carbon-steel tank liners holding the liquid waste do not sorb the radionuclides. Tank liners have been shown to form corrosion products, such as Fe-oxyhydroxides (Wiersma and Subramanian 2002). Many corrosion products, including Fe-oxyhydroxides, at the high pH values of tank effluent, take on a very strong negative charge. Given that many radionuclides may have netmore » positive charges, either as free ions or complexed species, it is expected that many radionuclides will sorb to corrosion products associated with tank liners. The objective of this report was to conduct a literature review to investigate whether Pu, U, Np, Am and Tc would sorb to corrosion products on tank liners after they were filled with reducing grout (cementitious material containing slag to promote reducing conditions). The approach was to evaluate radionuclides sorption literature with iron oxyhydroxide phases, such as hematite ({alpha}-Fe{sub 2}O{sub 3}), magnetite (Fe{sub 3}O{sub 4}), goethite ({alpha}-FeOOH) and ferrihydrite (Fe{sub 2}O{sub 3} {center_dot} 0.5H{sub 2}O). The primary interest was the sorption behavior under tank closure conditions where the tanks will be filled with reducing cementitious materials. Because there were no laboratory studies conducted using site specific experimental conditions, (e.g., high pH and HLW tank aqueous and solid phase chemical conditions), it was necessary to extend the literature review to lower pH studies and noncementitious conditions. Consequently, this report relied on existing lower pH trends, existing geochemical modeling, and experimental spectroscopic evidence conducted at lower pH levels. The scope did not include evaluating the

  10. Sustainability of renewable fuel infrastructure: a screening LCA case study of anticorrosive graphene oxide epoxy liners in steel tanks for the storage of biodiesel and its blends.

    PubMed

    Chilkoor, Govinda; Upadhyayula, Venkata K K; Gadhamshetty, Venkataramana; Koratkar, Nikhil; Tysklind, Mats

    2017-02-22

    Biodiesel is a widely used fuel that meets the renewable fuel standards developed under the Energy Policy Act of 2005. However, biodiesel is known to pose a series of abiotic and biotic corrosion risks to storage tanks. A typical practice (incumbent system) used to protect the tanks from these risks include (i) coating the interior surface of the tank with a solvent-free epoxy (SFE) liner, and (ii) adding a biocide to the tank. Herein, we present a screening-level life-cycle assessment study to compare the environmental performance of a graphene oxide (GO)-epoxy (GOE) liner with the incumbent system. TRACI was used as an impact assessment tool to model the midpoint environmental impacts in ten categories: global warming potential (GWP, kg CO 2 eq.); acidification potential (AP, kg SO 2 eq.); potential human health damage impacts due to carcinogens (HH-CP, CTU h ) and non-carcinogens (HH-NCP, CTU h ); potential respiratory effects (REP, kg PM 2.5 eq.); eutrophication potential (EP, kg N eq.); ozone depletion potential (ODP kg CFC-11 eq.); ecotoxicity potential (ETXP, CTU e ); smog formation potential (SFP kg O 3 eq.) and fossil fuel depletion potential (FFDP MJ surplus). The equivalent functional unit of the LCA study was designed to protect 30 m 2 of the interior surface (unalloyed steel sheet) of a 10 000 liter biodiesel tank against abiotic and biotic corrosion during its service life of 20 years. Overall, this LCA study highlights the improved environmental performance for the GOE liner compared to the incumbent system, whereby the GOE liner showed 91% lower impacts in ODP impact category, 59% smaller in REP, 62% smaller in AP, 67-69% smaller in GWP and HH-CP, 72-76% smaller in EP, SFP, and FFDP, and 81-83% smaller ETXP and HH-NCP category results. The scenario analysis study revealed that these potential impacts change by less than 15% when the GOE liners are functionalized with silanized-GO nanosheets or GO-reinforced polyvinyl carbazole to improve the

  11. Filament wound metal lined propellant tanks for future Earth-to-orbit transports

    NASA Technical Reports Server (NTRS)

    Macconochie, Ian O.; Davis, Robert B.; Freeman, William T., Jr.

    1988-01-01

    For future Earth-to-orbit transport vehicles, reusability and lighter weights are sought for the main propellant tanks. To achieve this, a filament wound tank with a metal liner and an intermediate layer of foam-filled honeycomb is proposed. A hydrogen tank is used as an example. To accommodate mismatches in the expansion of liner and overwrap a design is proposed wherin the liner is configured so that the extension of the liner under pressure matches the expected contraction of the same liner due to the presence of a cryogen. In operation, the liner is pressurized at a rate such that the pressure strain matches the contraction due to decrease in temperature. As an alternate approach, compressive pre-stress is placed in the liner such that it will not separate from the overwrap. A finite element program is used to show stresses in the liner and overwrap for various tank pressures for the pre-stressed liner concept. A fracture mechanics analysis is made of the liners to determine tank life. The tank concept shown has a similar weight to the Shuttle external hydrogen tank, but the filament wound tank is expected to be reusable. Integration of the propellant tanks into a future transport vehicle is discussed.

  12. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage tank...

  13. 7 CFR 58.320 - Brine tanks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Brine tanks. 58.320 Section 58.320 Agriculture....320 Brine tanks. Brine tanks used for the treating of parchment liners shall be constructed of... liners. The tank should also be provided with a satisfactory drainage outlet. ...

  14. 7 CFR 58.320 - Brine tanks.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Brine tanks. 58.320 Section 58.320 Agriculture....320 Brine tanks. Brine tanks used for the treating of parchment liners shall be constructed of... liners. The tank should also be provided with a satisfactory drainage outlet. ...

  15. 7 CFR 58.320 - Brine tanks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Brine tanks. 58.320 Section 58.320 Agriculture....320 Brine tanks. Brine tanks used for the treating of parchment liners shall be constructed of... liners. The tank should also be provided with a satisfactory drainage outlet. ...

  16. 7 CFR 58.320 - Brine tanks.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Brine tanks. 58.320 Section 58.320 Agriculture....320 Brine tanks. Brine tanks used for the treating of parchment liners shall be constructed of... liners. The tank should also be provided with a satisfactory drainage outlet. ...

  17. 7 CFR 58.320 - Brine tanks.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Brine tanks. 58.320 Section 58.320 Agriculture....320 Brine tanks. Brine tanks used for the treating of parchment liners shall be constructed of... liners. The tank should also be provided with a satisfactory drainage outlet. ...

  18. Cryogenic glass-filament-wound tank evaluation

    NASA Technical Reports Server (NTRS)

    Morris, E. E.; Landes, R. E.

    1971-01-01

    High-pressure glass-filament-wound fluid storage vessels with thin aluminum liners were designed, fabricated, and tested at ambient and cryogenic temperatures which demonstrated the feasibility of producing such vessels as well as high performance and light weight. Significant developments and advancements were made in solving problems associated with the thin metal liners in the tanks, including liner bonding to the overwrap and high strain magnification at the vessel polar bosses. The vessels had very high burst strengths, and failed in cyclic fatigue tests by local liner fracture and leakage without structural failure of the composite tank wall. The weight of the tanks was only 40 to 55% of comparable 2219-T87 aluminum and Inconel 718 tanks.

  19. Impact of landfill liner time-temperature history on the service life of HDPE geomembranes.

    PubMed

    Rowe, R Kerry; Islam, M Z

    2009-10-01

    The observed temperatures in different landfills are used to establish a number of idealized time-temperature histories for geomembrane liners in municipal solid waste (MSW) landfills. These are then used for estimating the service life of different HDPE geomembranes. The predicted antioxidant depletion times (Stage I) are between 7 and 750 years with the large variation depending on the specific HDPE geomembrane product, exposure conditions, and most importantly, the magnitude and duration of the peak liner temperature. The higher end of the range corresponds to data from geomembranes aged in simulated landfill liner tests and a maximum liner temperature of 37 degrees C. The lower end of the range corresponds to a testing condition where geomembranes were immersed in a synthetic leachate and a maximum liner temperature of 60 degrees C. The total service life of the geomembranes was estimated to be between 20 and 3300 years depending on the time-temperature history examined. The range illustrates the important role that time-temperature history could play in terms of geomembrane service life. The need for long-term monitoring of landfill liner temperature and for geomembrane ageing studies that will provide improved data for assessing the likely long-term performance of geomembranes in MSW landfills are highlighted.

  20. Gun Liner Emplacement With an Elastomeric Material

    DTIC Science & Technology

    2010-04-01

    Introduction The U.S. Army uses liners or coatings in many of its guns currently in service. This includes a chrome coating in the M256 main tank...coatings increase the barrel wear life of those guns by protecting them against the effects of hot propellant gasses. Chrome coatings are applied by...CCM is a chrome -cobalt alloy that is used for medical implants. The tube was machined from a solid bar of metal. The load frame was programmed to

  1. Strength, Fatigue, and Fracture Toughness of Ti-6Al-4V Liner from a Composite Over-Wrapped Pressure Vessel

    NASA Technical Reports Server (NTRS)

    Salem, Jonathan A.; Lerch, Brad; Thesken, John C.; Sutter, Jim; Russell, Richard

    2008-01-01

    It was demonstrated by way of experiment that Composite Over-wrapped Pressure Vessel (COPV) Ti-6Al-4V liner material can sustain the expected service loads and cycles. The experiments were performed as part of investigations on the residual life of COPV tanks being used in Space Shuttle Orbiters. Measured properties included tensile strength, compressive strength, reversed loading cycles to simulate liner proof strains, and cyclic fatigue loading to demonstrate the ability to sustain 1000 cycles after liner buckling. The liner material came from a salvaged 40 in. Columbia (orbiter 102) tank (SN029), and tensile strength measurements were made on both boss-transition (thick) and membrane regions (thin). The average measured yield strength was 131 ksi in the boss-transition and membrane regions, in good agreement with measurements made on 1970 s vintage forged plate stock. However, Young s modulus was 17.4+/-0.3 Msi, somewhat higher than typical handbook values (approx.16 Msi). The fracture toughness, as estimated from a failed fatigue specimen, was 74 ksi/sq in, in reasonable agreement with standardized measurements made on 1970 s vintage forged plate stock. Low cycle fatigue of a buckled test specimen implied that as-imprinted liners can sustain over 4000 load cycles.

  2. Fuel tank for liquefied natural gas

    NASA Technical Reports Server (NTRS)

    DeLay, Thomas K. (Inventor)

    2012-01-01

    A storage tank is provided for storing liquefied natural gas on, for example, a motor vehicle such as a bus or truck. The storage tank includes a metal liner vessel encapsulated by a resin-fiber composite layer. A foam insulating layer, including an outer protective layer of epoxy or of a truck liner material, covers the composite layer. A non-conducting protective coating may be painted on the vessel between the composite layer and the vessel so as to inhibit galvanic corrosion.

  3. 241-AZ Tank Farm Construction Extent of Condition Review for Tank Integrity

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

    Barnes, Travis J.; Boomer, Kayle D.; Gunter, Jason R.

    2013-07-30

    This report provides the results of an extent of condition construction history review for tanks 241-AZ-101 and 241-AZ-102. The construction history of the 241-AZ tank farm has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In the 241-AZ tank farm, the second DST farm constructed, both refractory quality and tank and liner fabrication were improved.

  4. 14 CFR 23.967 - Fuel tank installation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....967 Fuel tank installation. (a) Each fuel tank must be supported so that tank loads are not... tank liner is used, it must be supported so that it is not required to withstand fluid loads; (4... securing or loss of the fuel filler cap. (b) Each tank compartment must be ventilated and drained to...

  5. 14 CFR 23.967 - Fuel tank installation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....967 Fuel tank installation. (a) Each fuel tank must be supported so that tank loads are not... tank liner is used, it must be supported so that it is not required to withstand fluid loads; (4... securing or loss of the fuel filler cap. (b) Each tank compartment must be ventilated and drained to...

  6. 14 CFR 23.967 - Fuel tank installation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....967 Fuel tank installation. (a) Each fuel tank must be supported so that tank loads are not... tank liner is used, it must be supported so that it is not required to withstand fluid loads; (4... securing or loss of the fuel filler cap. (b) Each tank compartment must be ventilated and drained to...

  7. 14 CFR 23.967 - Fuel tank installation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....967 Fuel tank installation. (a) Each fuel tank must be supported so that tank loads are not... tank liner is used, it must be supported so that it is not required to withstand fluid loads; (4... securing or loss of the fuel filler cap. (b) Each tank compartment must be ventilated and drained to...

  8. 14 CFR 23.967 - Fuel tank installation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....967 Fuel tank installation. (a) Each fuel tank must be supported so that tank loads are not... tank liner is used, it must be supported so that it is not required to withstand fluid loads; (4... securing or loss of the fuel filler cap. (b) Each tank compartment must be ventilated and drained to...

  9. OVERVIEW OF ENHANCED HANFORD SINGLE-SHELL TANK (SST) INTEGRITY PROJECT - 12128

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

    VENETZ TJ; BOOMER KD; WASHENFELDER DJ

    2012-01-25

    analysis of current mechanics properties. The work on the liner leak integrity has examined the leaks from 23 tanks with liner failures. Individual leak assessments are being developed for each tank to identify the leak cause and location. Also a common cause study is being performed to take the data from individual tanks to look for trends in the failure. Supporting this work is an assessment of the leak rate from tanks at both Hanford and the Savannah River Site and a new method to locate leak sites in tank liner using ionic conductivity. A separate activity is being conducted to examine the propensity for corrosion in select single shell tanks with aggressive waste layers. The work for these two main efforts will provide the basis for the phase two planning. If the margins identified aren't sufficient to ensure the integrity through the life of the mission, phase two would focus on activities to further enhance the understanding of tank integrity. Also coincident with any phase-two work would be the integrity analysis for the tanks, which would be complete in 2018. With delays in the completion of waste treatment facilities at Hanford, greater reliance on safe, continued storage of waste in the single shell tanks is increased in importance. The goal of integrity assessment would provide basis to continue SST activities till the end of the treatment mission.« less

  10. Combustor liner durability analysis

    NASA Technical Reports Server (NTRS)

    Moreno, V.

    1981-01-01

    An 18 month combustor liner durability analysis program was conducted to evaluate the use of advanced three dimensional transient heat transfer and nonlinear stress-strain analyses for modeling the cyclic thermomechanical response of a simulated combustor liner specimen. Cyclic life prediction technology for creep/fatigue interaction is evaluated for a variety of state-of-the-art tools for crack initiation and propagation. The sensitivity of the initiation models to a change in the operating conditions is also assessed.

  11. Helium High Pressure Tanks at EADS Space Transportation New Technology with Thermoplastic Liner

    DTIC Science & Technology

    2005-07-13

    l’art actuel pour l’application d’un liner thermoplastique sur le réservoir hélium 300 litres pour le lanceur ARIANE 5, réservoir actuellement réalisé à...L à liner thermoplastique ont complètement démontré le respect aux exigences majeures demandées pour le lanceur A5. Ces travaux finalisent la phase

  12. Formed platelet combustor liner construction feasibility, phase A

    NASA Technical Reports Server (NTRS)

    Hayes, W. A.; Janke, D. E.

    1992-01-01

    Environments generated in high pressure liquid rocket engines impose severe requirements on regeneratively cooled combustor liners. Liners fabricated for use in high chamber pressures using conventional processes suffer from limitations that can impair operational cycle life and can adversely affect wall compatibility. Chamber liners fabricated using formed platelet technology provide an alternative to conventional regeneratively cooled liners (an alternative that has many attractive benefits). A formed platelet liner is made from a stacked assembly of platelets with channel features. The assembly is diffusion bonded into a flat panel and then three-dimensionally formed into a section of a chamber. Platelet technology permits the liner to have very precisely controlled and thin hot gas walls and therefore increased heat transfer efficiency. Further cooling efficiencies can be obtained through enhanced design flexibility. These advantages translate into increased cycle life and enhanced wall compatibility. The increased heat transfer efficiency can alternately be used to increase engine performance or turbopump life as a result of pressure drop reductions within the regeneratively cooled liner. Other benefits can be obtained by varying the materials of construction within the platelet liner to enhance material compatibility with operating environment or with adjoining components. Manufacturing cost savings are an additional benefit of a formed platelet liner. This is because of reduced touch labor and reduced schedule when compared to conventional methods of manufacture. The formed platelet technology is not only compatible with current state-of-the art combustion chamber structural support and manifolding schemes, it is also an enabling technology that allows the use of other high performance and potentially low cost methods of construction for the entire combustion chamber assembly. The contract under which this report is submitted contains three phases: (1) phase

  13. FGD liner experiments with wetlands

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

    Mitsch, W.J.; Ahn, C.; Wolfe, W.E.

    1999-07-01

    The construction of artificial wetlands for wastewater treatment often requires impermeable liners not only to protect groundwater resources but also to ensure that there is adequate water in the wetland to support appropriate aquatic life, particularly wetland vegetation. Liners or relatively impervious site soils are very important to the success of constructed treatment wetlands in areas where ground water levels are typically close to the ground surface. This study, carried out at the Olentangy River Wetland Research Park, investigated the use of FGD material from sulfur scrubbers as a possible liner material for constructed wetlands. While several studies have investigatedmore » the use of FGD material to line ponds, no studies have investigated the use of this material as a liner for constructed wetlands. They used experimental mesocosms to see the effect of FGD liner materials in constructed wetlands on water quality and on wetland plant growth. This paper presents the results of nutrient analyses and physicochemical investigation of leachate and surface outflow water samples collected from the mesocosms. Plant growth and biomass of wetland vegetation are also included in this paper. First two year results are reported by Ahn et al. (1998, 1999). The overall goal of this study is the identification of advantages and disadvantages of using FGD by-product as an artificial liner in constructed wetlands.« less

  14. Fracture Mechanics Analysis of LH2 Feed Line Flow Liners

    NASA Technical Reports Server (NTRS)

    James, Mark A.; Dawicke, David S.; Brzowski, Matthew B.; Raju, Ivatury S.; Elliott, Kenny B.; Harris, Charles E.

    2006-01-01

    Inspections of the Space Shuttle Main Engine revealed fatigue cracks growing from slots in the flow liner of the liquid hydrogen (LH2) feed lines. During flight, the flow liners experience complex loading induced by flow of LH2 and the resonance characteristics of the structure. The flow liners are made of Inconel 718 and had previously not been considered a fracture critical component. However, fatigue failure of a flow liner could have catastrophic effect on the Shuttle engines. A fracture mechanics study was performed to determine if a damage tolerance approach to life management was possible and to determine the sensitivity to the load spectra, material properties, and crack size. The load spectra were derived separately from ground tests and material properties were obtained from coupon tests. The stress-intensity factors for the fatigue cracks were determined from a shell-dynamics approach that simulated the dominant resonant frequencies. Life predictions were obtained using the NASGRO life prediction code. The results indicated that adequate life could not be demonstrated for initial crack lengths of the size that could be detected by traditional NDE techniques.

  15. VPS GRCop-84 Liner Development Efforts

    NASA Technical Reports Server (NTRS)

    Elam, Sandra K.; Holmes, Richard; McKechnie, Tim; Hickman, Robert; Pickens, Tim

    2003-01-01

    For the past several years, NASA's Marshall Space Flight Center (MSFC) has been working with Plasma Processes, Inc. (PPI) to fabricate combustion chamber liners using the Vacuum Plasma Spray (VPS) process. Multiple liners of a variety of shapes and sizes have been created. Each liner has been fabricated with GRCop-84 (a copper alloy with chromium and niobium) and a functional gradient coating (FGC) on the hot wall. While the VPS process offers versatility and a reduced fabrication schedule, the material system created with VPS allows the liners to operate at higher temperatures, with maximum blanch resistance and improved cycle life. A subscal unit (5K lbf thrust class) is being cycle tested in a LOX/Hydrogen thrust chamber assembly at MSFC. To date, over 75 hot-fire tests have been accumulated on this article. Tests include conditions normally detrimental to conventional materials, yet the VPS GRCop-84 liner has yet to show any signs of degradation. A larger chamber (15K lbf thrust class) has also been fabricated and is being prepared for hot-fire testing at MSFC near the end of 2003. Linear liners have been successfully created to further demonstrate the versatility of the process. Finally, scale up issues for the VPS process are being tackled with efforts to fabricate a full size, engine class liner. Specifically, a liner for the SSME's Main Combustion Chamber (MCC) has recently been attempted. The SSME size was chosen for convenience, since its design was readily available and its size was sufficient to tackle specific issues. Efforts to fabricate these large liners have already provided valuable lessons for using this process for engine programs. The material quality for these large units is being evaluated with destructive analysis and these results will be available by the end of 2003.

  16. Comprehensive review of geosynthetic clay liner and compacted clay liner

    NASA Astrophysics Data System (ADS)

    Shankar, M. Uma; Muthukumar, M.

    2017-11-01

    Human activity inevitably produces waste materials that must be managed. Some waste can be reused. However many wastes that cannot be used beneficially must be disposed of ensuring environmental safety. One of the common methods of disposal is landfilling. The most common problems of the landfill site are environmental degradation and groundwater contamination caused by leachate produced during the decomposition process of organic material and rainfall. Liner in a landfill is an important component which prevent leachate migration and prevent groundwater contamination. Earthen liners have been widely used to contain waste materials in landfill. Liners and covers for municipal and hazardous waste containment facilities are often constructed with the use of fine-grained, low plasticity soils. Because of low permeability geosynthetic clay liners and compacted clay liners are the main materials used in waste disposal landfills. This paper summaries the important geotechnical characteristics such as hydraulic conductivity, liquid limit and free swell index of geosynthetic clay liner and compacted clay liner based on research findings. This paper also compares geosynthetic clay liner and compacted clay liner based on certain criteria such as thickness, availability of materials, vulnerability to damage etc.

  17. Development and flight test of metal-lined CFRP cryogenic tank for reusable rocket

    NASA Astrophysics Data System (ADS)

    Higuchi, Ken; Takeuchi, Shinsuke; Sato, Eiichi; Naruo, Yoshihiro; Inatani, Yoshifumi; Namiki, Fumiharu; Tanaka, Kohtaro; Watabe, Yoko

    2005-07-01

    A cryogenic tank made of carbon fiber reinforced plastic (CFRP) shell with aluminum thin liner has been designed as a liquid hydrogen (LH2) tank for an ISAS reusable launch vehicle, and the function of it has been proven by repeated flights onboard the test vehicle called reusable vehicle testing (RVT) in October 2003. The liquid hydrogen tank has to be a pressure vessel, because the fuel of the engine of the test vehicle is supplied by fuel pressure. The pressure vessel of a combination of the outer shell of CFRP for strength element at a cryogenic temperature and the inner liner of aluminum for gas barrier has shown excellent weight merit for this purpose. Interfaces such as tank outline shape, bulk capacity, maximum expected operating pressure (MEOP), thermal insulation, pipe arrangement, and measurement of data are also designed to be ready onboard. This research has many aims, not only development of reusable cryogenic composite tank but also the demonstration of repeated operation including thermal cycle and stress cycle, familiarization with test techniques of operation of cryogenic composite tanks, and the accumulation of data for future design of tanks, vehicle structures, safety evaluation, and total operation systems.

  18. Progress in Hanford's Double-Shell Tank Integrity Project

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

    Bryson, D.C.; Washenfelder, D.J.; Boomer, K.D.

    2008-07-01

    The U.S. Department of Energy's Office of River Protection has an extensive integrity assessment program for the Hanford Site Double-Shell Tank System. The DOE Orders and environmental protection regulations provide the guidelines for the activities used to inspect and maintain 28 double-shell tanks (DSTs), the waste evaporator, and ancillary equipment that compose this system. This program has been reviewed by oversight and regulatory bodies and found to comply with the established guidelines. The basis for the DOE Order 435.1-1 for tank integrity comes from the Tank Structural Integrity Panel led by Brookhaven National Laboratory during the late 1990's. These guidelinesmore » established criteria for performing Non-Destructive Examination (NDE), for acceptance of the NDE results, for waste chemistry control, and for monitoring the tanks. The environmental regulations mirror these requirements and allow for the tank integrity program to provide compliant storage of the tanks. Both sets of requirements provide additional guidance for the protection of ancillary equipment. CH2M HILL uses two methods of NDE: visual inspection and Ultrasonic Testing (UT). The visual inspection program examines the primary tank and secondary liner of the DST. The primary tank is examined both on the interior surface above the waste in the tank and on the exterior surface facing the annulus of the DST. The interior surface of the tank liner is examined at the same time as the outer surface of the primary tank. The UT program examines representative areas of the primary tank and secondary liner by deploying equipment in the annulus of the tank. Both programs have led to the development of new equipment for remote inspection of the tanks. Compact camera and enhanced lighting systems have been designed and deployed through narrow access ports (called risers) into the tanks. The UT program has designed two generations of crawlers and equipment for deployment through risers into the

  19. Optimized multisectioned acoustic liners

    NASA Technical Reports Server (NTRS)

    Baumeister, K. J.

    1979-01-01

    New calculations show that segmenting is most efficient at high frequencies with relatively long duct lengths where the attenuation is low for both uniform and segmented liners. Statistical considerations indicate little advantage in using optimized liners with more than two segments while the bandwidth of an optimized two-segment liner is shown to be nearly equal to that of a uniform liner. Multielement liner calculations show a large degradation in performance due to changes in assumed input modal structure. Computer programs are used to generate theoretical attenuations for a number of liner configurations for liners in a rectangular duct with no mean flow. Overall, the use of optimized multisectioned liners fails to offer sufficient advantage over a uniform liner to warrant their use except in low frequency single mode application.

  20. SDU6 Interior Liner Testing & Evaluation

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

    Skidmore, T. E.

    Two liner materials (Marseal® M-3500 and REMA Chemoline® 4CN) proposed for use as a liner inside the Saltstone Disposal Unit 6 (SDU6) were subjected to specific ASTM tests (tensile and lap-shear) after immersion in 50% and 100% simulant solutions for 1000 hours at the Savannah River Ecology Laboratory. Both liner materials exhibited good resistance to the simulant chemistry, at least based on the tests performed and the test duration/conditions imposed. In lap-shear tests, both materials failed in the base material rather than peeling apart, confirming good adhesion. The REMA 4CN bromobutyl elastomer showed superior bonding characteristics and absence of warpingmore » or delamination at the conditions tested. The Marseal M-3500 material (PVC/EVA blend with polyester reinforcement) exhibited deformation and debonding in some locations. The cause of the deformation and delamination observed in the Marseal M-3500 material is not fully known, but possibly attributed to thermomechanical stress at immersion temperatures, and the thermoplastic nature of the material. The immersion temperature (68 °C) is slightly greater than the maximum use temperature limit quoted for the Marseal M- 3500 liner (65 °C), though the basis for the service limit is unknown. The testing performed was limited in scope and only for these two liner materials. These tests were primarily performed to screen for severe incompatibility or short-term degradation in Saltstone bleedwater simulants at bounding solution temperatures. Additional testing is recommended to assess long-term performance and the overall service life of the liner.« less

  1. Novel Materials for Prosthetic Liners

    NASA Technical Reports Server (NTRS)

    Ragolta, Carolina I.; Morford, Megan

    2011-01-01

    Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury that reduce quality of life. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications. Three tests were performed on several types of aerogel to assess the properties of each material. Moisture vapor permeability was tested by incubating four aerogel varieties with an artificial sweat solution at 37.0 C and less than 20% relative humidity for 24 hours. Two aerogel varieties were eliminated from the study due to difficulties in handling the material, and further testing proceeded with Pyrogel in 2.0 and 6.0 mm thicknesses. Force distribution was tested by compressing samples under a load of 4448 N at a rate of 2.5 mm/min. Biofilm formation was tested in a high-shear CDC Biofilm Reactor. Results showed that 2.0 mm Pyrogel blanket allowed 55.7 plus or minus 28.7% of an artificial sweat solution to transpire, and 35.5 plus or minus 27.8% transpired through 6.0 mm Pyrogel blanket. Samples also outperformed the load-bearing capabilities of existing liner materials. No statistically significant difference was found between the two Pyrogel thicknesses for either moisture vapor permeability or force distribution. In addition, biofilm formation results showed no change between the two Pyrogel thicknesses. The breathability and load bearing properties of aerogel make it a suitable material for application to prosthetic liners.

  2. Single-Shell Tanks Leak Integrity Elements/ SX Farm Leak Causes and Locations - 12127

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

    Girardot, Crystal; Harlow, Don; Venetz, Theodore

    2012-07-01

    Washington River Protection Solutions, LLC (WRPS) developed an enhanced single-shell tank (SST) integrity project in 2009. An expert panel on SST integrity was created to provide recommendations supporting the development of the project. One primary recommendation was to expand the leak assessment reports (substitute report or LD-1) to include leak causes and locations. The recommendation has been included in the M-045-91F Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) as one of four targets relating to SST leak integrity. The 241-SX Farm (SX Farm) tanks with leak losses were addressed on an individual tank basis as part of LD-1.more » Currently, 8 out of 23 SSTs that have been reported to having a liner leak are located in SX Farm. This percentage was the highest compared to other tank farms which is why SX Farm was analyzed first. The SX Farm is comprised of fifteen SSTs built 1953-1954. The tanks are arranged in rows of three tanks each, forming a cascade. Each of the SX Farm tanks has a nominal 1-million-gal storage capacity. Of the fifteen tanks in SX Farm, an assessment reported leak losses for the following tanks: 241-SX-107, 241-SX-108, 241-SX-109, 241-SX- 111, 241-SX-112, 241-SX-113, 241-SX-114 and 241-SX-115. The method used to identify leak location consisted of reviewing in-tank and ex-tank leak detection information. This provided the basic data identifying where and when the first leaks were detected. In-tank leak detection consisted of liquid level measurement that can be augmented with photographs which can provide an indication of the vertical leak location on the sidewall. Ex-tank leak detection for the leaking tanks consisted of soil radiation data from laterals and dry-wells near the tank. The in-tank and ex-tank leak detection can provide an indication of the possible leak location radially around and under the tank. Potential leak causes were determined using in-tank and ex-tank information that is not directly

  3. SINGLE-SHELL TANKS LEAK INTEGRITY ELEMENTS/SX FARM LEAK CAUSES AND LOCATIONS - 12127

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

    VENETZ TJ; WASHENFELDER D; JOHNSON J

    2012-01-25

    Washington River Protection Solutions, LLC (WRPS) developed an enhanced single-shell tank (SST) integrity project in 2009. An expert panel on SST integrity was created to provide recommendations supporting the development of the project. One primary recommendation was to expand the leak assessment reports (substitute report or LD-1) to include leak causes and locations. The recommendation has been included in the M-045-9IF Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) as one of four targets relating to SST leak integrity. The 241-SX Farm (SX Farm) tanks with leak losses were addressed on an individual tank basis as part of LD-1.more » Currently, 8 out of 23 SSTs that have been reported to having a liner leak are located in SX Farm. This percentage was the highest compared to other tank farms which is why SX Farm was analyzed first. The SX Farm is comprised of fifteen SSTs built 1953-1954. The tanks are arranged in rows of three tanks each, forming a cascade. Each of the SX Farm tanks has a nominal I-million-gal storage capacity. Of the fifteen tanks in SX Farm, an assessment reported leak losses for the following tanks: 241-SX-107, 241-SX-108, 241-SX-109, 241-SX-111, 241-SX-112, 241-SX-113, 241-SX-114 and 241-SX-115. The method used to identify leak location consisted of reviewing in-tank and ex-tank leak detection information. This provided the basic data identifying where and when the first leaks were detected. In-tank leak detection consisted of liquid level measurement that can be augmented with photographs which can provide an indication of the vertical leak location on the sidewall. Ex-tank leak detection for the leaking tanks consisted of soil radiation data from laterals and drywells near the tank. The in-tank and ex-tank leak detection can provide an indication of the possible leak location radially around and under the tank. Potential leak causes were determined using in-tank and ex-tank information that is not directly

  4. DEVELOPMENT OF ASME SECTION X CODE RULES FOR HIGH PRESSURE COMPOSITE HYDROGEN PRESSURE VESSELS WITH NON-LOAD SHARING LINERS

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

    Rawls, G.; Newhouse, N.; Rana, M.

    2010-04-13

    The Boiler and Pressure Vessel Project Team on Hydrogen Tanks was formed in 2004 to develop Code rules to address the various needs that had been identified for the design and construction of up to 15000 psi hydrogen storage vessel. One of these needs was the development of Code rules for high pressure composite vessels with non-load sharing liners for stationary applications. In 2009, ASME approved new Appendix 8, for Section X Code which contains the rules for these vessels. These vessels are designated as Class III vessels with design pressure ranging from 20.7 MPa (3,000 ps)i to 103.4 MPamore » (15,000 psi) and maximum allowable outside liner diameter of 2.54 m (100 inches). The maximum design life of these vessels is limited to 20 years. Design, fabrication, and examination requirements have been specified, included Acoustic Emission testing at time of manufacture. The Code rules include the design qualification testing of prototype vessels. Qualification includes proof, expansion, burst, cyclic fatigue, creep, flaw, permeability, torque, penetration, and environmental testing.« less

  5. Selected topics in railroad tank car safety. Volume 2 : test plan for accelerated life testing of thermally shielded tank cars

    DOT National Transportation Integrated Search

    1978-08-01

    A test plan for the accelerated life testing of thermally shielded tank cars is described. The test program would be conducted at the DOT Transportation Test Center in Pueblo, Colorado. Eighteen tank cars would be included in the program. Five cars w...

  6. Design of crusher liner based on time - varying uncertainty theory

    NASA Astrophysics Data System (ADS)

    Tang, J. C.; Shi, B. Q.; Yu, H. J.; Wang, R. J.; Zhang, W. Y.

    2017-09-01

    This article puts forward the time-dependent design method considering the load fluctuation factors for the liner based on the time-varying uncertainty theory. In this method, the time-varying uncertainty design model of liner is constructed by introducing the parameters that affect the wear rate, the volatility and the drift rate. Based on the design example, the timevarying design outline of the moving cone liner is obtained. Based on the theory of minimum wear, the gap curve of wear resistant cavity is designed, and the optimized cavity is obtained by the combination of the thickness of the cone and the cavity gap. Taking the PYGB1821 multi cylinder hydraulic cone crusher as an example, it is proved that the service life of the new liner is improved by more than 14.3%.

  7. Composite overwrapped metallic tanks

    NASA Technical Reports Server (NTRS)

    Caudill, C. L.; Kirlin, R. L.

    1972-01-01

    Work is reported for fabricating and testing the fiberglass overwrapped titanium pressure vessel for cryogenic service. Difficulties encountered in the tank liner fabrication phase involved explosive forming, vacuum annealing, chemical milling and electron beam welding. While each of these processes and the nondestructive test methods employed are normally considered to be individually reliable, the combination of poor material together with fabrication and development reversals prevented the full achievement of the desired end results. Eight tanks plus a prototype and tool proofing article were produced. Six of the vessels failed during the hydrostatic sizing operation. One of the remaining tanks was hydrostatically pressurized to burst and the other was pressurized repeatedly at 75 F from 100 psi to the operating pressure until failure occurred. As a result, it is not possible to draw firm conclusions as to the true value of the design concept due to the problems encountered in the program.

  8. Liner mounting assembly

    NASA Technical Reports Server (NTRS)

    Halila, Ely E. (Inventor)

    1994-01-01

    A mounting assembly includes an annular supporting flange disposed coaxially about a centerline axis which has a plurality of circumferentially spaced apart supporting holes therethrough. An annular liner is disposed coaxially with the supporting flange and includes a plurality of circumferentially spaced apart mounting holes aligned with respective ones of the supporting holes. Each of a plurality of mounting pins includes a proximal end fixedly joined to the supporting flange through a respective one of the supporting holes, and a distal end disposed through a respective one of the liner mounting holes for supporting the liner to the supporting flange while unrestrained differential thermal movement of the liner relative to the supporting flange.

  9. Retrospective Study of In-Service CIPP Liners

    EPA Science Inventory

    Cured-in-place pipe (CIPP) has been used for rehabilitation of deteriorating wastewater pipes for nearly 30 years in the US with much success. However, little quantitative data is available regarding the performance of these liners, to verify their estimated design life of 50 yea...

  10. Effects of broadened property fuels on radiant heat flux to gas turbine combustor liners

    NASA Technical Reports Server (NTRS)

    Haggard, J. B., Jr.

    1983-01-01

    The effects of fuel type, inlet air pressure, inlet air temperature, and fuel/air ratio on the combustor radiation were investigated. Combustor liner radiant heat flux measurements were made in the spectral region between 0.14 and 6.5 microns at three locations in a modified commercial aviation can combustor. Two fuels, Jet A and a heavier distillate research fuel called ERBS were used. The use of ERBS fuel as opposed to Jet A under similar operating conditions resulted in increased radiation to the combustor liner and hence increased backside liner temperature. This increased radiation resulted in liner temperature increases always less than 73 C. The increased radiation is shown by way of calculations to be the result of increased soot concentrations in the combustor. The increased liner temperatures indicated can substantially affect engine maintenance costs by reducing combustor liner life up to 1/3 because of the rapid decay in liner material properties when operated beyond their design conditions.

  11. Configuration Effects on Liner Performance

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Jones, Michael G.; Howerton, Brian M.

    2012-01-01

    The acoustic performance of a duct liner depends not only on the intrinsic properties of the liner but also on the configuration of the duct in which it is used. A series of experiments is performed in the NASA Langley Research Center Curved Duct Test Rig (at Mach 0.275) to evaluate the effect of duct configuration on the acoustic performance of single degree of freedom perforate-over-honeycomb liners. The liners form the sidewalls of the duct's test section. Variations of duct configuration include: asymmetric (liner on one side and hard wall opposite) and symmetric (liner on both sides) wall treatment; inlet and exhaust orientation, in which the sound propagates either against or with the flow; and straight and curved flow path. The effect that duct configuration has on the overall acoustic performance, particularly the shift in frequency and magnitude of peak attenuation, is quantified. The redistribution of incident mode content is shown. The liners constitute the side walls of the liner test section and the scatter of incident horizontal order 1 mode by the asymmetric treatment and order 2 mode by the symmetric treatment into order 0 mode is shown. Scatter of order 0 incident modes into higher order modes is also shown. This redistribution of mode content is significant because it indicates that the liner design can be manipulated such that energy is scattered into more highly attenuated modes, thus enhancing liner performance.

  12. Beryllium liner implosion experiments on the Z accelerator in preparation for magnetized liner inertial fusiona)

    NASA Astrophysics Data System (ADS)

    McBride, R. D.; Martin, M. R.; Lemke, R. W.; Greenly, J. B.; Jennings, C. A.; Rovang, D. C.; Sinars, D. B.; Cuneo, M. E.; Herrmann, M. C.; Slutz, S. A.; Nakhleh, C. W.; Ryutov, D. D.; Davis, J.-P.; Flicker, D. G.; Blue, B. E.; Tomlinson, K.; Schroen, D.; Stamm, R. M.; Smith, G. E.; Moore, J. K.; Rogers, T. J.; Robertson, G. K.; Kamm, R. J.; Smith, I. C.; Savage, M.; Stygar, W. A.; Rochau, G. A.; Jones, M.; Lopez, M. R.; Porter, J. L.; Matzen, M. K.

    2013-05-01

    Multiple experimental campaigns have been executed to study the implosions of initially solid beryllium (Be) liners (tubes) on the Z pulsed-power accelerator. The implosions were driven by current pulses that rose from 0 to 20 MA in either 100 or 200 ns (200 ns for pulse shaping experiments). These studies were conducted in support of the recently proposed Magnetized Liner Inertial Fusion concept [Slutz et al., Phys. Plasmas 17, 056303 (2010)], as well as for exploring novel equation-of-state measurement techniques. The experiments used thick-walled liners that had an aspect ratio (initial outer radius divided by initial wall thickness) of either 3.2, 4, or 6. From these studies, we present three new primary results. First, we present radiographic images of imploding Be liners, where each liner contained a thin aluminum sleeve for enhancing the contrast and visibility of the liner's inner surface in the images. These images allow us to assess the stability of the liner's inner surface more accurately and more directly than was previously possible. Second, we present radiographic images taken early in the implosion (prior to any motion of the liner's inner surface) of a shockwave propagating radially inward through the liner wall. Radial mass density profiles from these shock compression experiments are contrasted with profiles from experiments where the Z accelerator's pulse shaping capabilities were used to achieve shockless ("quasi-isentropic") liner compression. Third, we present "micro-Ḃ" measurements of azimuthal magnetic field penetration into the initially vacuum-filled interior of a shocked liner. Our measurements and simulations reveal that the penetration commences shortly after the shockwave breaks out from the liner's inner surface. The field then accelerates this low-density "precursor" plasma to the axis of symmetry.

  13. Beryllium liner implosion experiments on the Z accelerator in preparation for magnetized liner inertial fusion

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

    McBride, R. D.; Martin, M. R.; Lemke, R. W.

    Multiple experimental campaigns have been executed to study the implosions of initially solid beryllium (Be) liners (tubes) on the Z pulsed-power accelerator. The implosions were driven by current pulses that rose from 0 to 20 MA in either 100 or 200 ns (200 ns for pulse shaping experiments). These studies were conducted in support of the recently proposed Magnetized Liner Inertial Fusion concept [Slutz et al., Phys. Plasmas 17, 056303 (2010)], as well as for exploring novel equation-of-state measurement techniques. The experiments used thick-walled liners that had an aspect ratio (initial outer radius divided by initial wall thickness) of eithermore » 3.2, 4, or 6. From these studies, we present three new primary results. First, we present radiographic images of imploding Be liners, where each liner contained a thin aluminum sleeve for enhancing the contrast and visibility of the liner's inner surface in the images. These images allow us to assess the stability of the liner's inner surface more accurately and more directly than was previously possible. Second, we present radiographic images taken early in the implosion (prior to any motion of the liner's inner surface) of a shockwave propagating radially inward through the liner wall. Radial mass density profiles from these shock compression experiments are contrasted with profiles from experiments where the Z accelerator's pulse shaping capabilities were used to achieve shockless (“quasi-isentropic”) liner compression. Third, we present “micro-B-dot ” measurements of azimuthal magnetic field penetration into the initially vacuum-filled interior of a shocked liner. Our measurements and simulations reveal that the penetration commences shortly after the shockwave breaks out from the liner's inner surface. The field then accelerates this low-density “precursor” plasma to the axis of symmetry.« less

  14. FORENSIC INVESTIGATION OF A GENERATION OLD CIPP LINER

    EPA Science Inventory

    There is limited information regarding the in-situ performance of rehabilitation methods used for prolonging the service life of buried municipal pipeline systems. With some CIPP liners nearly 30 years in service, municipalities are expressing a strong interest in the collection ...

  15. Hanford Double-Shell Tank AY-102 Radioactive Waste Leak Investigation Update - 15302

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

    Washenfelder, D. J.; Johnson, J. M.

    2014-12-22

    Tank AY-102 was the first of 28 double-shell radioactive waste storage tanks constructed at the U. S. Department of Energy’s Hanford Site, near Richland, WA. The tank was completed in 1970, and entered service in 1971. In August, 2012, an accumulation of material was discovered at two sites on the floor of the annulus that separates the primary tank from the secondary liner. The material was sampled and determined to originate from the primary tank. This paper summarizes the changes in leak behavior that have occurred during the past two years, inspections to determine the capability of the secondary linermore » to continue safely containing the leakage, and the initial results of testing to determine the leak mechanism.« less

  16. Segmented Liner to Control Mode Scattering

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Jones, Michael G.; Brown, Martha C.

    2013-01-01

    The acoustic performance of duct liners can be improved by segmenting the treatment. In a segmented liner treatment, one stage of liner reduces the target sound and scatters energy into other acoustic modes, which are attenuated by a subsequent stage. The Curved Duct Test Rig is an experimental facility in which sound incident on the liner can be generated in a specific mode and the scatter of energy into other modes can be quantified. A series of experiments is performed in which the baseline configuration is asymmetric, that is, a liner is on one side wall of the test duct and the wall opposite is acoustically hard. Segmented liner treatment is achieved by progressively replacing sections of the hard wall opposite with liner in the axial direction, from 25% of the wall surface to 100%. It is found that the energy scatter from the (0,0) to the (0,1) mode reduces as the percentage of opposite wall treatment increases, and the frequency of peak attenuation shifts toward higher frequency. Similar results are found when the incident mode is of order (0,1) and scatter is into the (0,0) mode. The propagation code CDUCT-LaRC is used to predict the effect of liner segmenting on liner performance. The computational results show energy scatter and the effect of liner segmentation that agrees with the experimental results. The experiments and computations both show that segmenting the liner treatment is effective to control the scatter of incident mode energy into other modes. CDUCT-LaRC is shown to be a valuable tool to predict trends of liner performance with liner configuration.

  17. Polymer/Silicate Nanocomposites Used to Manufacture Gas Storage Tanks With Reduced Permeability

    NASA Technical Reports Server (NTRS)

    Campbell, Sandi G.; Johnston, Chris

    2004-01-01

    Over the past decade, there has been considerable research in the area of polymer-layered silicate nanocomposites. This research has shown that the dispersion of small amounts of an organically modified layered silicate improves the polymer strength, modulus, thermal stability, and barrier properties. There have been several reports on the dispersion of layered silicates in an epoxy matrix. Potential enhancements to the barrier properties of epoxy/silicate nanocomposites make this material attractive for low permeability tankage. Polymer matrix composites (PMCs) have several advantages for cryogenic storage tanks. They are lightweight, strong, and stiff; therefore, a smaller fraction of a vehicle's potential payload capacity is used for propellant storage. Unfortunately, the resins typically used to make PMC tanks have higher gas permeability than metals. This can lead to hydrogen loss through the body of the tank instead of just at welds and fittings. One approach to eliminate this problem is to build composite tanks with thin metal liners. However, although these tanks provide good permeability performance, they suffer from a substantial mismatch in the coefficient of thermal expansion, which can lead to failure of the bond between the liner and the body of the tank. Both problems could be addressed with polymersilicate nanocomposites, which exhibit reduced hydrogen permeability, making them potential candidates for linerless PMC tanks. Through collaboration with Northrop Grumman and Michigan State University, nanocomposite test tanks were manufactured for the NASA Glenn Research Center, and the helium permeability was measured. An organically modified silicate was prepared at Michigan State University and dispersed in an epoxy matrix (EPON 826/JeffamineD230). The epoxy/silicate nanocomposites contained either 0 or 5 wt% of the organically modified silicate. The tanks were made by filament winding carbon fibers with the nanocomposite resin. Helium permeability

  18. Ditching Investigation of a 1/15-Scale Model of the Convair-Liner Airplane

    NASA Technical Reports Server (NTRS)

    Fisher, Lloyd J.; Thompson, William C.

    1950-01-01

    A ditching investigation of a model of the Convair-Liner airplane was made to observe the behavior and determine the safest procedure for making an emergency water landing. The ditching model was designed and constructed by the National Advisory Committee for Aeronautics. Design information on the airplane was furnished by the Consolidated Vultee Aircraft Corporation. A three-view drawing of the airplane is shown. The investigation was made in calm water at the Langley tank no. 2 monorail.

  19. EVALUATION OF LANDFILL-LINER DESIGNS

    EPA Science Inventory

    The effectiveness of landfill-liner designs is evaluated in terms of the slope, drainage length, and saturated hydraulic conductivity of the lateral drainage layer, the saturated hydraulic conductivity of the soil liner, and the fraction of the area under a synthetic liner where ...

  20. Acoustic Liners for Turbine Engines

    NASA Technical Reports Server (NTRS)

    Jones, Michael G (Inventor); Grady, Joseph E (Inventor); Heidmann, James D. (Inventor); Kiser, James D. (Inventor); Miller, Christopher (Inventor)

    2016-01-01

    An improved acoustic liner for turbine engines is disclosed. The acoustic liner may include a straight cell section including a plurality of cells with straight chambers. The acoustic liner may also include a bent cell section including one or more cells that are bent to extend chamber length without increasing the overall height of the acoustic liner by the entire chamber length. In some cases, holes are placed between cell chambers in addition to bending the cells, or instead of bending the cells.

  1. Segmented ceramic liner for induction furnaces

    DOEpatents

    Gorin, Andrew H.; Holcombe, Cressie E.

    1994-01-01

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace.

  2. Segmented ceramic liner for induction furnaces

    DOEpatents

    Gorin, A.H.; Holcombe, C.E.

    1994-07-26

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace. 5 figs.

  3. [Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

    PubMed

    Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

    1989-01-01

    We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide.

  4. ACOUSTIC LINERS FOR TURBOFAN ENGINES

    NASA Technical Reports Server (NTRS)

    Minner, G. L.

    1994-01-01

    This program was developed to design acoustic liners for turbofan engines. This program combines results from theoretical models of wave alternation in acoustically treated passages with experimental data from full-scale fan noise suppressors. By including experimentally obtained information, the program accounts for real effects such as wall boundary layers, duct terminations, and sound modal structure. The program has its greatest use in generating a number of design specifications to be used for evaluation of trade-offs. The program combines theoretical and empirical data in designing annular acoustic liners. First an estimate of the noise output of the fan is made based on basic fan aerodynamic design variables. Then, using a target noise spectrum after alternation and the estimated fan noise spectrum, a design spectrum is calculated as their difference. Next, the design spectrum is combined with knowledge of acoustic liner performance and the liner design variables to specify the acoustic design. Details of the liner design are calculated by combining the required acoustic impedance with a mathematical model relating acoustic impedance to the physical structure of the liner. Input to the noise prediction part of the program consists of basic fan operating parameters, distance that the target spectrum is to be measured and the target spectrum. The liner design portion of the program requires the required alternation spectrum, desired values of length to height and several option selection parameters. Output from the noise prediction portion is a noise spectrum consisting of discrete tones and broadband noise. This may be used as input to the liner design portion of the program. The liner design portion of the program produces backing depths, open area ratios, and face plate thicknesses. This program is written in FORTRAN V and has been implemented in batch mode on a UNIVAC 1100 series computer with a central memory requirement of 12K (decimal) of 36 bit words.

  5. RCRA, superfund and EPCRA hotline training module. Introduction to: Tanks (40 cfr parts 264/265, subpart j) updated July 1996

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

    NONE

    1996-07-01

    The module identifies, based on tank contents and operation, tanks that are regulated under parts 264/265, subpart J. It defines specific terms pertaining to hazardous waste tanks, and provides CFR or Federal Register citations. It distinguishes `new tanks` from `existing tanks` and identifies how this status affects applicable regulations. It discusses secondary containment requirements for liners, vaults, and double-walled tanks, as well as secondary containment for ancillary equipment. It identifies which of the hazardous waste requirements were promulgated under the Hazardous and Solid Waste Amendments (HSWA) and non-HSWA authority and explains how each applies in authorized and unauthorized states.

  6. An analytical model for solute transport through a GCL-based two-layered liner considering biodegradation.

    PubMed

    Guan, C; Xie, H J; Wang, Y Z; Chen, Y M; Jiang, Y S; Tang, X W

    2014-01-01

    An analytical model for solute advection and dispersion in a two-layered liner consisting of a geosynthetic clay liner (GCL) and a soil liner (SL) considering the effect of biodegradation was proposed. The analytical solution was derived by Laplace transformation and was validated over a range of parameters using the finite-layer method based software Pollute v7.0. Results show that if the half-life of the solute in GCL is larger than 1 year, the degradation in GCL can be neglected for solute transport in GCL/SL. When the half-life of GCL is less than 1 year, neglecting the effect of degradation in GCL on solute migration will result in a large difference of relative base concentration of GCL/SL (e.g., 32% for the case with half-life of 0.01 year). The 100-year solute base concentration can be reduced by a factor of 2.2 when the hydraulic conductivity of the SL was reduced by an order of magnitude. The 100-year base concentration was reduced by a factor of 155 when the half life of the contaminant in the SL was reduced by an order of magnitude. The effect of degradation is more important in approving the groundwater protection level than the hydraulic conductivity. The analytical solution can be used for experimental data fitting, verification of complicated numerical models and preliminary design of landfill liner systems. © 2013.

  7. Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Eskridge, Richard; Smith, James; Lee, Michael; Richeson, Jeff; Schmidt, George; Knapp, Charles E.; Kirkpatrick, Ronald C.; Turchi, Peter J.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Magnetized target fusion (MTF) attempts to combine the favorable attributes of magnetic confinement fusion (MCF) for energy confinement with the attributes of inertial confinement fusion (ICF) for efficient compression heating and wall-free containment of the fusing plasma. It uses a material liner to compress and contain a magnetized plasma. For practical applications, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC). For the successful implementation of the scheme, plasma jets of the requisite momentum flux density need to be produced. Their transport over sufficiently large distances (a few meters) needs to be assured. When they collide and merge into a liner, relative differences in velocity, density and temperature of the jets could give rise to instabilities in the development of the liner. Variation in the jet properties must be controlled to ensure that the growth rate of the instabilities are not significant over the time scale of the liner formation before engaging with the target plasma. On impact with the target plasma, some plasma interpenetration might occur between the liner and the target. The operating parameter space needs to be identified to ensure that a reasonably robust and conducting contact surface is formed between the liner and the target. A mismatch in the "impedance" between the liner and the target plasma could give rise to undesirable shock heating of the liner leading to increased entropy (thermal losses) in the liner. Any irregularities in the liner will accentuate the Rayleigh-Taylor instabilities during the compression of the target plasma by the liner.

  8. LINER FOR EXTRUSION BILLET CONTAINERS

    DTIC Science & Technology

    Shrink-fit assembly device for buildup of ceramic-coated liner and sleeve assemblies was tested and modified to develop desired temperatures and...preliminary evaluation of suitability for extrusion liner use. Procedures were developed for welding short, hollow ceramic cylinders of high-strength metal...carbides and borides to form a ceramic extrusion liner of suitable length. Disassembly tooling for rapid separation of shrink-fitted sleeves from a worn

  9. Composite Overwrap Pressure Vessels: Mechanics and Stress Rupture Lifing Philosophy

    NASA Technical Reports Server (NTRS)

    Thesken, John C.; Murthy, Pappu L. N.; Phoenix, Leigh

    2007-01-01

    The NASA Engineering and Safety Center (NESC) has been conducting an independent technical assessment to address safety concerns related to the known stress rupture failure mode of filament wound pressure vessels in use on Shuttle and the International Space Station. The Shuttle's Kevlar-49 fiber overwrapped tanks are of particular concern due to their long usage and the poorly understood stress rupture process in Kevlar-49 filaments. Existing long term data show that the rupture process is a function of stress, temperature and time. However due to the presence of load sharing liners and the complex manufacturing procedures, the state of actual fiber stress in flight hardware and test articles is not clearly known. Indeed non-conservative life predictions have been made where stress rupture data and lifing procedures have ignored the contribution of the liner in favor of applied pressure as the controlling load parameter. With the aid of analytical and finite element results, this paper examines the fundamental mechanical response of composite overwrapped pressure vessels including the influence of elastic-plastic liners and degraded/creeping overwrap properties. Graphical methods are presented describing the non-linear relationship of applied pressure to Kevlar-49 fiber stress/strain during manufacturing, operations and burst loadings. These are applied to experimental measurements made on a variety of vessel systems to demonstrate the correct calibration of fiber stress as a function of pressure. Applying this analysis to the actual qualification burst data for Shuttle flight hardware revealed that the nominal fiber stress at burst was in some cases 23% lower than what had previously been used to predict stress rupture life. These results motivate a detailed discussion of the appropriate stress rupture lifing philosophy for COPVs including the correct transference of stress rupture life data between dissimilar vessels and test articles.

  10. Water movement through an experimental soil liner

    USGS Publications Warehouse

    Krapac, I.G.; Cartwright, K.; Panno, S.V.; Hensel, B.R.; Rehfeldt, K.R.; Herzog, B.L.

    1991-01-01

    A field-scale soil liner was constructed to test whether compacted soil barriers in cover and liner systems could be built to meet the U.S. EPA saturated hydraulic conductivity requirement (???1 x 10-7 cm s-1). The 8 x 15 x 0.9m liner was constructed in 15 cm compacted lifts using a 20,037 kg pad-foot compactor and standard engineering practices. Water infiltration into the liner has been monitored for one year. Monitoring will continue until water break through at the base of the liner occurs. Estimated saturated hydraulic conductivities were 2.5 x 10-9, 4.0 x 10-8, and 5.0 x 10-8 cm s-1 based on measurements of water infiltration into the liner by large- and small-ring infiltrometers and a water balance analysis, respectively. Also investigated in this research was the variability of the liner's hydraulic properties and estimates of the transit times for water and tracers. Small variances exhibited by small-ring flux data suggested that the liner was homogeneous with respect to infiltration fluxes. The predictions of water and tracer breakthrough at the base of the liner ranged from 2.4-12.6 y, depending on the method of calculation and assumptions made. The liner appeared to be saturated to a depth between 18 and 33 cm at the end of the first year of monitoring. Transit time calculations cannot be verified yet, since breakthrough has not occurred. The work conducted so far indicates that compacted soil barriers can be constructed to meet the saturated hydraulic conductivity requirement established by the U.S. EPA.A field-scale soil liner was constructed to test whether compacted soil barriers in cover and liner systems could be built to meet the U.S. EPA saturated hydraulic conductivity requirement (??? 1 ?? 10-7 cm s-1). The 8 ?? 15 ?? 0.9 m liner was constructed in 15 cm compacted lifts using a 20.037 kg pad-foot compactor and standard engineering practices. Water infiltration into the liner has been monitored for one year. Monitoring will continue until water

  11. Pocketing mechanics of SRM nozzle liner

    NASA Technical Reports Server (NTRS)

    Verderaime, V. S.

    1986-01-01

    A systems approach was adopted to study the pocketing phenomena on a solid rocket nozzle liner. The classical thermoelastic analysis was used to identify marginally strained regions on the composite liner erosion surface and at a depth coincident with the peak value of the across ply coefficient of thermal expansion. A failure criterion was introduced which included a thermal term and permitted failure assessment over the charred liner. The method was verified by satisfactory application to a reported related experiment. Liner pocketing mechanism was attributed to very localized material degradation caused during manufacturing process either by reduction of fiber strength and/or by concentration of resin volume fraction. Pocketing scenario over the degraged material was constructed with supporting formulation to predict size of fissures with respect to degraded material size and location in the liner and with burn time. Sensitivities of liner material parameters were determined to influence test programs designed to update mechanical data base of carbon cloth phenolic over the char temperature range.

  12. In vivo degradation of polyethylene liners after gamma sterilization in air.

    PubMed

    Kurtz, Steven M; Rimnac, Clare M; Hozack, William J; Turner, Joseph; Marcolongo, Michele; Goldberg, Victor M; Kraay, Matthew J; Edidin, Avram A

    2005-04-01

    Ultra-high molecular weight polyethylene degrades during storage in air following gamma sterilization, but the extent of in vivo degradation remains unclear. The purpose of this study was to quantify the extent to which the mechanical properties and oxidation of conventional polyethylene acetabular liners treated with gamma sterilization in air change in vivo. Fourteen modular cementless acetabular liners were revised at an average of 10.3 years (range, 5.9 to 13.5 years) after implantation. All liners, which had been machined from GUR 415 resin, had been gamma-sterilized in air; the average shelf life was 0.3 year (range, 0.0 to 0.8 year). After removal, the components were expeditiously frozen to minimize ex vivo changes to the polyethylene prior to characterization. The average duration between freezing and testing was 0.6 year. Mechanical properties and oxidation were measured with use of the small-punch test and Fourier transform infrared spectroscopy, respectively, in the loaded and unloaded regions of the liners. There was substantial regional variation in the mechanical properties and oxidation of the retrieved liners. The ultimate load was observed to vary by >90% near the surface. On the average, the rim and the unloaded bearing showed evidence of severe oxidation near the surface after long-term in vivo aging, but these trends were not typically observed on the loaded bearing surface or near the backside of the liners. The mechanical properties of polyethylene that has been gamma-sterilized in air may decrease substantially in vivo, depending on the location in the liner. The most severe oxidation was observed at the rim, suggesting that the femoral head inhibits access of oxygen-containing body fluids to the bearing surface. This is perhaps why in vivo oxidation has not been associated with clinical performance to date.

  13. High Thermal Conductivity NARloy-Z-Diamond Composite Liner for Advanced Rocket Engines

    NASA Technical Reports Server (NTRS)

    Bhat, Biliyar; Greene, Sandra

    2015-01-01

    NARloy-Z (Cu-3Ag-0.5Zr) alloy is state-of-the-art combustion chamber liner material used in liquid propulsion engines such as the RS-68 and RS-25. The performance of future liquid propulsion systems can be improved significantly by increasing the heat transfer through the combustion chamber liner. Prior work1 done at NASA Marshall Space Flight Center (MSFC) has shown that the thermal conductivity of NARloy-Z alloy can be improved significantly by embedding high thermal conductivity diamond particles in the alloy matrix to form NARloy-Z-diamond composite (fig. 1). NARloy-Z-diamond composite containing 40vol% diamond showed 69% higher thermal conductivity than NARloy-Z. It is 24% lighter than NARloy-Z and hence the density normalized thermal conductivity is 120% better. These attributes will improve the performance and life of the advanced rocket engines significantly. The research work consists of (a) developing design properties (thermal and mechanical) of NARloy-Z-D composite, (b) fabrication of net shape subscale combustion chamber liner, and (c) hot-fire testing of the liner to test performance. Initially, NARloy-Z-D composite slabs were made using the Field Assisted Sintering Technology (FAST) for the purpose of determining design properties. In the next step, a cylindrical shape was fabricated to demonstrate feasibility (fig. 3). The liner consists of six cylinders which are sintered separately and then stacked and diffusion bonded to make the liner (fig. 4). The liner will be heat treated, finish-machined, and assembled into a combustion chamber and hot-fire tested in the MSFC test facility (TF 115) to determine perform.

  14. Variable volume combustor with a conical liner support

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

    Johnson, Thomas Edward; McConnaughhay, Johnie Franklin; Keener, Chrisophter Paul

    The present application provides a variable volume combustor for use with a gas turbine engine. The variable volume combustor may include a liner, a number of micro-mixer fuel nozzles positioned within the liner, and a conical liner support supporting the liner.

  15. Shock wave absorber having a deformable liner

    DOEpatents

    Youngdahl, C.K.; Wiedermann, A.H.; Shin, Y.W.; Kot, C.A.; Ockert, C.E.

    1983-08-26

    This invention discloses a shock wave absorber for a piping system carrying liquid. The absorber has a plastically deformable liner defining the normal flow boundary for an axial segment of the piping system, and a nondeformable housing is spaced outwardly from the liner so as to define a gas-tight space therebetween. The flow capacity of the liner generally corresponds to the flow capacity of the piping system line, but the liner has a noncircular cross section and extends axially of the piping system line a distance between one and twenty times the diameter thereof. Gas pressurizes the gas-tight space equal to the normal liquid pressure in the piping system. The liner has sufficient structural capacity to withstand between one and one-half and two times this normal liquid pressures; but at greater pressures it begins to plastically deform initially with respect to shape to a more circular cross section, and then with respect to material extension by circumferentially stretching the wall of the liner. A high energy shock wave passing through the liner thus plastically deforms the liner radially into the gas space and progressively also as needed in the axial direction of the shock wave to minimize transmission of the shock wave beyond the absorber.

  16. Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Cassibry, Jason; Eskridge, Richard; Kirkpatrick, Ronald C.; Knapp, Charles E.; Lee, Michael; Martin, Adam; Smith, James; Wu, S. T.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    For practical applications of magnetized target fusion, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Quasi-spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a quasi-spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC). Theoretical analysis and computer modeling of the concept are presented. It is shown that, with the appropriate choice of the flow parameters in the liner and the target, the impact between the liner and the target plasma can be made to be shockless in the liner or to generate at most a very weak shock in the liner. Additional information is contained in the original extended abstract.

  17. FOAM-IN-PLACE FORM FITTING HELMET LINERS

    DTIC Science & Technology

    A urethane foam formulation has been developed to produce foamed-in-place helmet liners for Air Force crash or flying helmets. High density urethane...foam helmet liners has been foamed-in-place directly on the flying crew member’s head, producing a perfectly fitting helmet liner with a minimum of...time, labor and inconvenience. These liners were produced at an extremely modest cost. Design and fabrication of a suitable mold in which the helmet

  18. Spherical Cryogenic Hydrogen Tank Preliminary Design Trade Studies

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    A structural analysis, sizing optimization, and weight prediction study was performed by Collier Research Corporation and NASA Glenn on a spherical cryogenic hydrogen tank. The tank consisted of an inner and outer wall separated by a vacuum for thermal insulation purposes. HyperSizer (Collier Research and Development Corporation), a commercial automated structural analysis and sizing software package was used to design the lightest feasible tank for a given overall size and thermomechanical loading environment. Weight trade studies were completed for different panel concepts and metallic and composite material systems. Extensive failure analyses were performed for each combination of dimensional variables, materials, and layups to establish the structural integrity of tank designs. Detailed stress and strain fields were computed from operational temperature changes and pressure loads. The inner tank wall is sized by the resulting biaxial tensile stresses which cause it to be strength driven, and leads to an optimum panel concept that need not be stiffened. Conversely, the outer tank wall is sized by a biaxial compressive stress field, induced by the pressure differential between atmospheric pressure and the vacuum between the tanks, thereby causing the design to be stability driven and thus stiffened to prevent buckling. Induced thermal stresses become a major sizing driver when a composite or hybrid composite/metallic material systems are used for the inner tank wall for purposes such as liners to contain the fuel and reduce hydrogen permeation.

  19. ELECTRICAL LEAK LOCATION METHOD FOR GEOMEMBRANE LINERS

    EPA Science Inventory

    Geomembrane liners are sheets of polymeric materials used to prevent leakage of waste from and infiltration of rainwater into solid waste landfills and surface impoundments. The method described consists of voltage applied between the liner and the earth under the liner which pro...

  20. Progress of the Enhanced Hanford Single Shell Tank (SST) Integrity Project

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

    Venetz, Theodore J.; Washenfelder, Dennis J.; Boomer, Kayle D.

    2015-01-07

    To improve the understanding of the single-shell tanks (SSTs) integrity, Washington River Protection Solutions, LLC (WRPS), the USDOE Hanford Site tank contractor, developed an enhanced Single-Shell Tank Integrity Project (SSTIP) in 2009. An expert panel on SST integrity, consisting of various subject matters experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration. In late 2010, seventeen of these recommendations were used to develop the basis for the M-45-10-1 Changemore » Package for the Hanford Federal Agreement and Compliance Order, which is also known as the Tri-Party Agreement.« less

  1. Elastic Plastic Fracture Analysis of an Aluminum COPV Liner

    NASA Technical Reports Server (NTRS)

    Forth, Scott; Gregg, Bradley; Bailey, Nathaniel

    2012-01-01

    Onboard any space-launch vehicle, composite over-wrapped pressure vessels (COPVs) may be utilized by propulsion or environmental control systems. The failure of a COPV has the potential to be catastrophic, resulting in the loss of vehicle, crew or mission. The latest COPV designs have reduced the wall-thickness of the metallic liner to the point where the material strains plastically during operation. At this time, the only method to determine the damage tolerance lifetime (safe-life) of a plastically responding metallic liner is through full-scale COPV testing. Conducting tests costs substantially more and can be far more time consuming than performing an analysis. As a result of this cost, there is a need to establish a qualifying process through the use of a crack growth analysis tool. This paper will discuss fracture analyses of plastically responding metallic liners in COPVs. Uni-axial strain tests have been completed on laboratory specimens to collect elastic-plastic crack growth data. This data has been modeled with the crack growth analysis tool, NASGRO 6.20 to predict the response of laboratory specimens and subsequently the complexity of a COPV.

  2. Test Method Designed to Evaluate Cylinder Liner-Piston Ring Coatings for Advanced Heat Engines

    NASA Technical Reports Server (NTRS)

    Radil, Kevin C.

    1997-01-01

    Research on advanced heat engine concepts, such as the low-heat-rejection engine, have shown the potential for increased thermal efficiency, reduced emissions, lighter weight, simpler design, and longer life in comparison to current diesel engine designs. A major obstacle in the development of a functional advanced heat engine is overcoming the problems caused by the high combustion temperatures at the piston ring/cylinder liner interface, specifically at top ring reversal (TRR). Therefore, advanced cylinder liner and piston ring materials are needed that can survive under these extreme conditions. To address this need, researchers at the NASA Lewis Research Center have designed a tribological test method to help evaluate candidate piston ring and cylinder liner materials for advanced diesel engines.

  3. Physics Criteria for a Subscale Plasma Liner Experiment

    DOE PAGES

    Hsu, Scott C.; Thio, Yong C. Francis

    2018-02-02

    Spherically imploding plasma liners, formed by merging hypersonic plasma jets, are a proposed standoff driver to compress magnetized target plasmas to fusion conditions (Hsu et al. in IEEE Trans Plasma Sci 40:1287, 2012). Here, in this paper, the parameter space and physics criteria are identified for a subscale, plasma-liner-formation experiment to provide data, e.g., on liner ram-pressure scaling and uniformity, that are relevant for addressing scientific issues of full-scale plasma liners required to achieve fusion conditions. Lastly, based on these criteria, we quantitatively estimate the minimum liner kinetic energy and mass needed, which informed the design of a subscale plasmamore » liner experiment now under development.« less

  4. Physics Criteria for a Subscale Plasma Liner Experiment

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

    Hsu, Scott C.; Thio, Yong C. Francis

    Spherically imploding plasma liners, formed by merging hypersonic plasma jets, are a proposed standoff driver to compress magnetized target plasmas to fusion conditions (Hsu et al. in IEEE Trans Plasma Sci 40:1287, 2012). Here, in this paper, the parameter space and physics criteria are identified for a subscale, plasma-liner-formation experiment to provide data, e.g., on liner ram-pressure scaling and uniformity, that are relevant for addressing scientific issues of full-scale plasma liners required to achieve fusion conditions. Lastly, based on these criteria, we quantitatively estimate the minimum liner kinetic energy and mass needed, which informed the design of a subscale plasmamore » liner experiment now under development.« less

  5. Geosynthetic clay liners shrinkage under simulated daily thermal cycles.

    PubMed

    Sarabadani, Hamid; Rayhani, Mohammad T

    2014-06-01

    Geosynthetic clay liners are used as part of composite liner systems in municipal solid waste landfills and other applications to restrict the escape of contaminants into the surrounding environment. This is attainable provided that the geosynthetic clay liner panels continuously cover the subsoil. Previous case histories, however, have shown that some geosynthetic clay liner panels are prone to significant shrinkage and separation when an overlying geomembrane is exposed to solar radiation. Experimental models were initiated to evaluate the potential shrinkage of different geosynthetic clay liner products placed over sand and clay subsoils, subjected to simulated daily thermal cycles (60°C for 8 hours and 22°C for 16 hours) modelling field conditions in which the liner is exposed to solar radiation. The variation of geosynthetic clay liner shrinkage was evaluated at specified times by a photogrammetry technique. The manufacturing techniques, the initial moisture content, and the aspect ratio (ratio of length to width) of the geosynthetic clay liner were found to considerably affect the shrinkage of geosynthetic clay liners. The particle size distribution of the subsoil and the associated suction at the geosynthetic clay liner-subsoil interface was also found to have significant effects on the shrinkage of the geosynthetic clay liner. © The Author(s) 2014.

  6. High temperature molten salt storage

    NASA Astrophysics Data System (ADS)

    Ives, J.; Newcomb, J. C.; Pard, A. G.

    1985-10-01

    The design of a high-temperature molten salt thermal energy storage (TES) concept, including some materials testing, was developed by Rockwell International's Rocketdyne Division (RD), under contract to SERI, and is described in this document. The main features of the concept are a conical hot tank with a liner and internal insulation that allows unrestricted relative thermal expansion and the use of cathodic protection (impressed voltage) to inhibit corrosion. The RD design uses two tanks and ternary eutectic lithium-sodium-potassium carbonates for sensible heat storage. The tanks were sized for 6 h of storage at a discharge rate of 300 MW, giving 1800 MWh total usable thermal storage capacity. The molten carbonate storage medium is cycled between 425 and 900C. From the design study, no definitive statement can be made as to the cost-effectiveness of cathodic protection. Several anode design issues need to be resolved before cathodic protection can significantly reduce corrosion where the liner comes in contact with molten salts. However, where the tank is exposed to salt vapor, the large corrosion allowance required for the liner without cathodic protection results in a much thicker liner wall and shorter liner life than originally perceived, which affects system costs significantly.

  7. Manufacturing Complicated Shells And Liners

    NASA Technical Reports Server (NTRS)

    Sobol, Paul J.; Faucher, Joseph E.

    1993-01-01

    Explosive forming, wax filling, and any one of welding, diffusion bonding, or brazing used in method of manufacturing large, complicated shell-and-liner vessels or structures. Method conceived for manufacture of film-cooled rocket nozzles but applicable to joining large coaxial shells and liners in general.

  8. Polyurethane gel liner usage in the Oxford Prosthetic Service.

    PubMed

    Hatfield, A G; Morrison, J D

    2001-04-01

    The objective was to investigate which lower limb amputees are using Alpha polyurethane gel liners and the effects of these on comfort and suspension of their prosthesis. A retrospective study was carried out of case records of all patients issued with Alpha cushion and locking liners between 1997 and the end of January 1999. The type of liner used was compared with age, sex, level and cause of amputation, time since amputation, comfort and suspension. Modified Stanmore/Harold-Wood mobility grades; duration of use and number of liners issued per patient were recorded. Sixteen (16) patients were identified who had been prescribed Alpha cushion liners. Improved comfort was reported by all. Forty (40) patients were identified who had been prescribed Alpha locking liners. Twenty (20) of these reported improved comfort and 10 improved suspension. The average time since amputation was 18.5 years for those using cushion liners and 14.1 years for locking liner users. Fifty-two (52) of all 56 patients using Alpha cushion and locking liners had mobility grades of 4 or more. Trauma was the most common cause of amputation. This group is a relatively mobile group of amputees. All those using cushion liners reported improved comfort. Some of the locking liner users reported improved comfort and suspension but this was not universally the case.

  9. Machine Gun Liner Bond Strength

    DTIC Science & Technology

    2007-08-01

    explosive bonding of pure tantalum, several tantalum alloys, and Stellite 25 (an alloy of cobalt, chrome , nickel, and tungsten) in a liner...smoothly as elastic stresses increase in the plug and liner. At a certain level of displacement, the load reaches a peak and then drops sharply. The

  10. Advanced Turbofan Duct Liner Concepts

    NASA Technical Reports Server (NTRS)

    Bielak, Gerald W.; Premo, John W.; Hersh, Alan S.

    1999-01-01

    The Advanced Subsonic Technology Noise Reduction Program goal is to reduce aircraft noise by 10 EPNdB by the year 2000 relative, to 1992 technology. The improvement goal for nacelle attenuation is 25% relative to 1992 technology by 1997 and 50% by 2000. The Advanced Turbofan Duct Liner Concepts Task work by Boeing presented in this document was in support of these goals. The basis for the technical approach was a Boeing study conducted in 1993-94 under NASA/FAA contract NAS1-19349, Task 6, investigating broadband acoustic liner concepts. As a result of this work, it was recommended that linear double layer, linear and perforate triple layer, parallel element, and bulk absorber liners be further investigated to improve nacelle attenuations. NASA LaRC also suggested that "adaptive" liner concepts that would allow "in-situ" acoustic impedance control also be considered. As a result, bias flow and high-temperature liner concepts were also added to the investigation. The major conclusion from the above studies is that improvements in nacelle liner average acoustic impedance characteristics alone will not result in 25% increased nacelle noise reduction relative to 1992 technology. Nacelle design advancements currently being developed by Boeing are expected to add 20-40% more acoustic lining to hardwall regions in current inlets, which is predicted to result in and additional 40-80% attenuation improvement. Similar advancements are expected to allow 10-30% more acoustic lining in current fan ducts with 10-30% more attenuation expected. In addition, Boeing is currently developing a scarf inlet concept which is expected to give an additional 40-80% attenuation improvement for equivalent lining areas.

  11. Think Tanks

    NASA Technical Reports Server (NTRS)

    2001-01-01

    A new inspection robot from Solex Robotics Systems was designed to eliminate hazardous inspections of petroleum and chemical storage tanks. The submersible robot, named Maverick, is used to inspect the bottoms of tanks, keeping the tanks operational during inspection. Maverick is able to provide services that will make manual tank inspections obsolete. While the inspection is conducted, Maverick's remote human operators remain safe outside of the tank. The risk to human health and life is now virtually eliminated. The risk to the environment is also minimal because there is a reduced chance of spillage from emptying and cleaning the tanks, where previously, tons of pollutants were released through the process of draining and refilling.

  12. Development of 1D Liner Compression Code for IDL

    NASA Astrophysics Data System (ADS)

    Shimazu, Akihisa; Slough, John; Pancotti, Anthony

    2015-11-01

    A 1D liner compression code is developed to model liner implosion dynamics in the Inductively Driven Liner Experiment (IDL) where FRC plasmoid is compressed via inductively-driven metal liners. The driver circuit, magnetic field, joule heating, and liner dynamics calculations are performed at each time step in sequence to couple these effects in the code. To obtain more realistic magnetic field results for a given drive coil geometry, 2D and 3D effects are incorporated into the 1D field calculation through use of correction factor table lookup approach. Commercial low-frequency electromagnetic fields solver, ANSYS Maxwell 3D, is used to solve the magnetic field profile for static liner condition at various liner radius in order to derive correction factors for the 1D field calculation in the code. The liner dynamics results from the code is verified to be in good agreement with the results from commercial explicit dynamics solver, ANSYS Explicit Dynamics, and previous liner experiment. The developed code is used to optimize the capacitor bank and driver coil design for better energy transfer and coupling. FRC gain calculations are also performed using the liner compression data from the code for the conceptual design of the reactor sized system for fusion energy gains.

  13. ONERA-NASA Cooperative Effort on Liner Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Primus, Julien; Piot, Estelle; Simon, Frank; Jones, Michael G.; Watson, Willie R

    2013-01-01

    As part of a cooperation between ONERA and NASA, the liner impedance eduction methods developed by the two research centers are compared. The NASA technique relies on an objective function built on acoustic pressure measurements located on the wall opposite the test liner, and the propagation code solves the convected Helmholtz equation in uniform ow using a finite element method that implements a continuous Galerkin discretization. The ONERA method uses an objective function based either on wall acoustic pressure or on acoustic velocity acquired above the liner by Laser Doppler Anemometry, and the propagation code solves the linearized Euler equations by a discontinuous Galerkin discretization. Two acoustic liners are tested in both ONERA and NASA ow ducts and the measured data are treated with the corresponding impedance eduction method. The first liner is a wire mesh facesheet mounted onto a honeycomb core, designed to be linear with respect to incident sound pressure level and to grazing ow velocity. The second one is a conventional, nonlinear, perforate-over-honeycomb single layer liner. Configurations without and with ow are considered. For the nonlinear liner, the comparison of liner impedance educed by NASA and ONERA shows a sensitivity to the experimental conditions, namely to the nature of the source and to the sample width.

  14. LINER galaxy properties and the local environment

    NASA Astrophysics Data System (ADS)

    Coldwell, Georgina V.; Alonso, Sol; Duplancic, Fernanda; Mesa, Valeria

    2018-05-01

    We analyse the properties of a sample of 5560 low-ionization nuclear emission-line region (LINER) galaxies selected from SDSS-DR12 at low red shift, for a complete range of local density environments. The host LINER galaxies were studied and compared with a well-defined control sample of 5553 non-LINER galaxies matched in red shift, luminosity, morphology and local density. By studying the distributions of galaxy colours and the stellar age population, we find that LINERs are redder and older than the control sample over a wide range of densities. In addition, LINERs are older than the control sample, at a given galaxy colour, indicating that some external process could have accelerated the evolution of the stellar population. The analysis of the host properties shows that the control sample exhibits a strong relation between colours, ages and the local density, while more than 90 per cent of the LINERs are redder and older than the mean values, independently of the neighbourhood density. Furthermore, a detailed study in three local density ranges shows that, while control sample galaxies are redder and older as a function of stellar mass and density, LINER galaxies mismatch the known morphology-density relation of galaxies without low-ionization features. The results support the contribution of hot and old stars to the low-ionization emission although the contribution of nuclear activity is not discarded.

  15. Effect of ceramic coating of JT8D combustor liner on maximum liner temperatures and other combustor performance parameters

    NASA Technical Reports Server (NTRS)

    Butze, H. F.; Liebert, C. H.

    1976-01-01

    The effect of ceramic coating of a JT8D combustor liner was investigated at simulated cruise and takeoff conditions with two fuels of widely different aromatic contents. Substantial decreases in maximum liner temperatures and flame radiation values were obtained with the ceramic-coated liner. Small reductions in exhaust gas smoke concentrations were observed with the ceramic-coated liner. Other performance parameters such as combustion efficiency and emissions of unburned hydrocarbons, CO, and NOx were not affected significantly. No deterioration of the ceramic coating was observed after about 6 hours of cyclic operation including several startups and shutdowns.

  16. Surface treatment using metal foil liner

    NASA Technical Reports Server (NTRS)

    Garvey, Ray

    1989-01-01

    A metal foil liner can be used to seal large area surfaces. Characteristics of the two-layer foil liner are discussed. Micrographs for foil-to-foil, foil-to-composite, visible seams, and hidden seams are examined.

  17. Cost Estimate for Gun Liner Emplacement

    DTIC Science & Technology

    2011-08-01

    material. The M2 machine gun has a Stellite 21 liner that covers only about one-half of the barrel length. It has been successful in reducing the...Michael R. M2 Machine Gun Barrel Wear with SLAP Ammunition. To be published in Journal of Materials and Manufacturing Processes. 8. Miller, Mark D...case in point is the use of a Stellite 21 liner in the M2 0.50-cal machine gun . However, liners have generally been difficult to place into gun tubes

  18. LINER FOR EXTRUSION BILLET CONTAINERS

    DTIC Science & Technology

    Rokide-process alumina and zirconia coatings and a Udimet 700 superalloy liner were evaluated by extrusion of 3 1/2-in. billets of Inconel 713C...One coating did with stand extrusion at 3450 F without apparent wear. The Udimet 700 liner did not show wear at 2000 F, but did react with the TZM

  19. Advanced liner-cooling techniques for gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Riddlebaugh, S. M.

    1985-01-01

    Component research for advanced small gas turbine engines is currently underway at the NASA Lewis Research Center. As part of this program, a basic reverse-flow combustor geometry was being maintained while different advanced liner wall cooling techniques were investigated. Performance and liner cooling effectiveness of the experimental combustor configuration featuring counter-flow film-cooled panels is presented and compared with two previously reported combustors featuring: splash film-cooled liner walls; and transpiration cooled liner walls (Lamilloy).

  20. Testing and Characterization of CMC Combustor Liners

    NASA Technical Reports Server (NTRS)

    Robinson, R. Craig; Verrilli, Michael J.

    2003-01-01

    Multiple combustor liner applications, both segmented and fully annular designs, have been configured for exposure in NASA's High Pressure Burner Rig (HPBR). The segmented liners were attached to the rig structure with SiC/SiC fasteners and exposed to simulated gas turbine conditions for nearly 200 hours. Test conditions included pressures of 6 atm., gas velocity of 42 m/s, and gas temperatures near 1450 C. The temperatures of both the cooled and combustion flow sides of the liners were measured using optical and contact measurement techniques. Minor weight loss was observed, but the liners remained structural sound, although damage was noted in some fasteners.

  1. A Conventional Liner Acoustic/Drag Interaction Benchmark Database

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Jones, Michael G.

    2017-01-01

    The aerodynamic drag of acoustic liners has become a significant topic in the design of such for aircraft noise applications. In order to evaluate the benefits of concepts designed to reduce liner drag, it is necessary to establish the baseline performance of liners employing the typical design features of conventional configurations. This paper details a set of experiments in the NASA Langley Grazing Flow Impedance Tube to quantify the relative drag of a number of perforate-over-honeycomb liner configurations at flow speeds of M=0.3 and 0.5. These conventional liners are investigated to determine their resistance factors using a static pressure drop approach. Comparison of the resistance factors gives a relative measurement of liner drag. For these same flow conditions, acoustic measurements are performed with tonal excitation from 400 to 3000 Hz at source sound pressure levels of 140 and 150 dB. Educed impedance and attenuation spectra are used to determine the interaction between acoustic performance and drag.

  2. The Nature of the Energy Source in LINER's

    NASA Technical Reports Server (NTRS)

    Colina, L.; Koratkar, Anuradha

    1996-01-01

    LINER's (low-ionization nuclear emission-line regions) are found in about 30% of all bright galaxies, including luminous infrared galaxies. They form a heterogeneous class powered by a variety of ionizing mechanisms such as low-luminosity AGNs (active galactic nuclei), starbursts, shocks, or any combination of these. In early-type spirals, LINER's are powered by a low-luminosity AGN, or by an AGN surrounded by circumnuclear star-forming regions. In luminous infrared galaxies, LINER's are powered by starbursts with associated wind-related extended shocks, and an AGN may play a minor role, if any. LINER's in some FR I radio galaxies show strong evidence for the presence of a massive central black hole, and there are indications for the existence of shocks in the nuclear disks of these galaxies. Yet, the dominant ionizing mechanism for LINER's in radio-quiet ellipticals and FR I host galaxies is still unclear. Multifrequency high spatial resolution imaging and spectroscopy are essential to discriminate among the different ionizing mechanisms present in LINER's.

  3. Stabilized Liner Compressor: The Return of Linus

    NASA Astrophysics Data System (ADS)

    Turchi, Peter; Frese, Sherry; Frese, Michael; Mielke, Charles; Hinrichs, Mark; Nguyen, Doan

    2015-11-01

    To access the lower cost regime of magneto-inertial fusion at megagauss magnetic field-levels requires the use of dynamic conductors in the form of imploding cylindrical shells, aka, liners. Such liner implosions can compress magnetic flux and plasma to attain fusion conditions, but are subject to Rayleigh-Taylor instabilities, both in the launch and recovery of the liner material and in the final few diameters of implosion. These instabilities were overcome in the Linus program at the Naval Research Laboratory, c. 1979, providing the experimentally-demonstrated basis for repetitive operation and leading to an economical reactor concept at low fusion gain. The recent ARPA-E program for low-cost fusion technology has revived interest in this approach. We shall discuss progress in modeling and design of a Stabilized Liner Compressor (SLC) that extends the earlier work to higher pressures and liner speeds appropriate to potential plasma targets. Sponsored by ARPA-E ALPHA Program.

  4. Graphical Acoustic Liner Design and Analysis Tool

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M. (Inventor); Jones, Michael G. (Inventor)

    2016-01-01

    An interactive liner design and impedance modeling tool comprises software utilized to design acoustic liners for use in constrained spaces, both regularly and irregularly shaped. A graphical user interface allows the acoustic channel geometry to be drawn in a liner volume while the surface impedance calculations are updated and displayed in real-time. A one-dimensional transmission line model may be used as the basis for the impedance calculations.

  5. Drapery assembly including insulated drapery liner

    DOEpatents

    Cukierski, Gwendolyn

    1983-01-01

    A drapery assembly is disclosed for covering a framed wall opening, the assembly including drapery panels hung on a horizontal traverse rod, the rod having a pair of master slides and means for displacing the master slides between open and closed positions. A pair of insulating liner panels are positioned behind the drapery, the remote side edges of the liner panels being connected with the side portions of the opening frame, and the adjacent side edges of the liner panels being connected with a pair of vertically arranged center support members adapted for sliding movement longitudinally of a horizontal track member secured to the upper horizontal portion of the opening frame. Pivotally arranged brackets connect the center support members with the master slides of the traverse rod whereby movement of the master slides to effect opening and closing of the drapery panels effects simultaneous opening and closing of the liner panels.

  6. Optimization and Control of Acoustic Liner Impedance with Bias Flow

    NASA Technical Reports Server (NTRS)

    Wood, Houston; Follet, Jesse

    2000-01-01

    Because communities are impacted by steady increases in aircraft traffic, aircraft noise continues to be a growing problem for the growth of commercial aviation. Research has focused on improving the design of specific high noise source areas of aircraft and on noise control measures to alleviate noise radiated from aircraft to the surrounding environment. Engine duct liners have long been a principal means of attenuating engine noise. The ability to control in-situ the acoustic impedance of a liner would provide a valuable tool to improve the performance of liners. The acoustic impedance of a liner is directly related to the sound absorption qualities of that liner. Increased attenuation rates, the ability to change liner acoustic impedance to match various operating conditions, or the ability to tune a liner to more precisely match design impedance represent some ways that in-situ impedance control could be useful. With this in mind, the research to be investigated will focus on improvements in the ability to control liner impedance using a mean flow through the liner which is referred to as bias flow.

  7. Broadband Liner Optimization for the Source Diagnostic Test Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.

    2012-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more appealing. This paper describes a broadband acoustic liner optimization study for the scale model Source Diagnostic Test fan. Specifically, in-duct attenuation predictions with a statistical fan source model are used to obtain optimum impedance spectra over a number of flow conditions for three liner locations in the bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Typical tonal liner designs targeting single frequencies at one operating condition are first produced to provide baseline performance information. These are followed by multiple broadband design approaches culminating in a broadband liner targeting the full range of frequencies and operating conditions. The broadband liner is found to satisfy the optimum impedance objectives much better than the tonal liner designs. In addition, the broadband liner is found to provide better attenuation than the tonal designs over the full range of frequencies and operating conditions considered. Thus, the current study successfully establishes a process for the initial design and evaluation of novel broadband liner concepts for complex engine configurations.

  8. User experience of transtibial prosthetic liners: A systematic review.

    PubMed

    Richardson, Amy; Dillon, Michael P

    2017-02-01

    The liner is an integral part of a transtibial prosthesis designed to protect the residual limb, enhance comfort and provide suspension. Literature is difficult to interpret and use given the variety of interventions, outcome measures and method designs. Critical appraisal and synthesis of the evidence is needed to help inform decisions about liner prescription based on the user experience. To critically appraise and synthesise research describing the user experience of transtibial prosthetic liners. Systematic review. A comprehensive suite of databases were searched using terms related to amputation level, liner type and user experience. Included studies were in English and measured the first-person experience of using a transtibial liner. Studies were appraised using the McMaster University Critical Review Forms. A total of 18 articles met the inclusion criteria. While the quality of the evidence has improved over time, a number of common issues (e.g. sampling bias, validity of outcome measures, incorrect inferential analysis) reduce our ability to differentiate between the user experience of different transtibial liners. There is insufficient research to differentiate between the user experience of different transtibial liners. High-quality research is needed to inform decisions about liner prescription based on the user experience. Clinical relevance The available evidence suggests that the user experience of commonly reported problems (e.g. sweating) may be very similar between different liners. Aspects of the user experience that differ most between liners (e.g. unwanted noises, rotation within the socket) can help focus attention on what matters most when discussing prescription.

  9. Hazardous waste treatment for spent pot liner

    NASA Astrophysics Data System (ADS)

    Zhao, Xia; Ma, Lei

    2018-01-01

    The spent pot liner is the largest solid waste produced by the electrolytic aluminum industry, composed of a series of substances that accumulate in the containers with reduced aluminum during the process of bauxite purification and refining. More and more spent pot liner is accumulated and needs to be dealt with. This paper discusses the composition and harm of solid waste. This paper expounds the comprehensive utilization value and disposition of the waste pot liner.

  10. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

  11. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

  12. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

  13. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

  14. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

  15. Foam-Metal Liner Attenuation of Low-Speed Fan Noise

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Jones, Michael G.

    2008-01-01

    A foam-metal liner for attenuation of fan noise was developed for and tested on a low speed fan. This type of liner represents a significant advance over traditional liners due to the possibility for placement in close proximity to the rotor. An advantage of placing treatment in this region is the modification of the acoustic near field, thereby inhibiting noise generation mechanisms. This can result in higher attenuation levels than can be achieved by liners located in the nacelle inlet. In addition, foam-metal liners could potentially replace the fan rub-strip and containment components, ultimately reducing engine components and thus weight, which can result in a systematic increase in noise reduction and engine performance. Foam-metal liners have the potential to reduce fan noise by 4 dB based on this study.

  16. Modular liquid-cooled helmet liner for thermal comfort

    NASA Technical Reports Server (NTRS)

    Williams, B. A.; Shitzer, A.

    1974-01-01

    A modular liquid-cooled helmet liner made of eight form-fitting neoprene patches was constructed. The liner was integrated into the sweatband of an Army SPH-4 helicopter aircrew helmet. This assembly was tested on four subjects seated in a hot (47 C), humid (40%) environment. Results indicate a marked reduction in the rate of increase of physiological body functions. Rectal temperature, weight loss, heart rate, and strain indices are all reduced to approximately 50% of uncooled levels. The cooling liner removed from 10% to 30% of total metabolic heat produced. This study also demonstrated the technical feasilibity of using a cooling liner in conjunction with a standard hard helmet. Potential applications of the cooling liner in thermally stressful environments are numerous, notably for helicopter and other aircrews.

  17. Heated Aluminum Tanks Resist Corrosion

    NASA Technical Reports Server (NTRS)

    Johnson, L. E.

    1983-01-01

    Simple expedient of heating foam-insulated aluminum alloy tanks prevents corrosion by salt-laden moisture. Relatively-small temperature difference between such tank and surrounding air will ensure life of tank is extended by many years.

  18. Duct Liner Optimization for Turbomachinery Noise Sources

    DTIC Science & Technology

    1975-11-01

    AD-A279 441lIIIflhIh* NASA TECHNICAL NASA TMA X-72789 MEMORANDUM oo £ 00 r-:. DUCT LINER OPTIMIZATION FOR TURBOMACHINERY w NOISE SOURCES By Harold C...Recipient’s r.atalog No. NASA TM X-72789! 4 Title diid Subtitle 5. Rewrt Date Duct Liner Optimization for Turbomachinery Noise Sources November 1975...profiles is combined wit., a numerical minimization algorithm to predict optimal liner configurations having one, two, and three sections. Source models

  19. Variable-Depth Liner Evaluation Using Two NASA Flow Ducts

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Nark, D. M.; Watson, W. R.; Howerton, B. M.

    2017-01-01

    Four liners are investigated experimentally via tests in the NASA Langley Grazing Flow Impedance Tube. These include an axially-segmented liner and three liners that use reordering of the chambers. Chamber reordering is shown to have a strong effect on the axial sound pressure level profiles, but a limited effect on the overall attenuation. It is also shown that bent chambers can be used to reduce the liner depth with minimal effects on the attenuation. A numerical study is also conducted to explore the effects of a planar and three higher-order mode sources based on the NASA Langley Curved Duct Test Rig geometry. A four-segment liner is designed using the NASA Langley CDL code with a Python-based optimizer. Five additional liner designs, four with rearrangements of the first liner segments and one with a redistribution of the individual chambers, are evaluated for each of the four sources. The liner configuration affects the sound pressure level profile much more than the attenuation spectra for the planar and first two higher-order mode sources, but has a much larger effect on the SPL profiles and attenuation spectra for the last higher-order mode source. Overall, axially variable-depth liners offer the potential to provide improved fan noise reduction, regardless of whether the axially variable depths are achieved via a distributed array of chambers (depths vary from chamber to chamber) or a group of zones (groups of chambers for which the depth is constant).

  20. Statistically Based Approach to Broadband Liner Design and Assessment

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Nark, Douglas M. (Inventor)

    2016-01-01

    A broadband liner design optimization includes utilizing in-duct attenuation predictions with a statistical fan source model to obtain optimum impedance spectra over a number of flow conditions for one or more liner locations in a bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners having impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increasing weighting to specific frequencies and/or operating conditions. One or more broadband design approaches are utilized to produce a broadband liner that targets a full range of frequencies and operating conditions.

  1. Evaluation of a Variable-Impedance Ceramic Matrix Composite Acoustic Liner

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2014-01-01

    As a result of significant progress in the reduction of fan and jet noise, there is growing concern regarding core noise. One method for achieving core noise reduction is via the use of acoustic liners. However, these liners must be constructed with materials suitable for high temperature environments and should be designed for optimum absorption of the broadband core noise spectrum. This paper presents results of tests conducted in the NASA Langley Liner Technology Facility to evaluate a variable-impedance ceramic matrix composite acoustic liner that offers the potential to achieve each of these goals. One concern is the porosity of the ceramic matrix composite material, and whether this might affect the predictability of liners constructed with this material. Comparisons between two variable-depth liners, one constructed with ceramic matrix composite material and the other constructed via stereolithography, are used to demonstrate this material porosity is not a concern. Also, some interesting observations are noted regarding the orientation of variable-depth liners. Finally, two propagation codes are validated via comparisons of predicted and measured acoustic pressure profiles for a variable-depth liner.

  2. Effect of flowable composite liner and glass ionomer liner on class II gingival marginal adaptation of direct composite restorations with different bonding strategies.

    PubMed

    Aggarwal, Vivek; Singla, Mamta; Yadav, Suman; Yadav, Harish

    2014-05-01

    The purpose of the present study was to comparatively evaluate the effect of flowable composite resin liner and resin modified glass ionomer liner on gingival marginal adaptation of class II cavities restored using three bonding agents (Single Bond 3M ESPE, One Coat Self Etching Bond Coltene Whaledent; Adper Easy Bond Self-Etch Adhesive 3M ESPE) and respective composite resins, under cyclic loading. The marginal adaptation was evaluated in terms of 'continuous margin' (CM) at the gingival margin. Ninety class II cavities with margins extending 1mm below the cement-enamel junction were prepared in extracted mandibular third molars. The samples were divided into three groups: no liner placement; 0.5-1mm thick flowable resin liner placement (Filtek Z350 XT flowable resin) on gingival floor and; light cure glass ionomer (Ketac N100) liner. The groups were further subdivided into three sub-groups on the basis of the bonding agents used. Cavities were restored with composite resins (Z350 for Single Bond and Adper Easy Bond; and Synergy D6 Universal, for One Coat Self Etching Bond) in 2mm increments and the samples were mechanically loaded (60N, 1,50,000 cycles). Marginal adaptation was evaluated using a low vacuum scanning electron microscope. Statistical analysis was done with two way ANOVA with Holm-Sidak's correction for multiple comparisons. Placement of flowable composite liner significantly improved the CM values of Single Bond (78±11%) and One Coat Self Etching Bond (77±9%) compared with no liner group, but the values of CM of Adper Easy Bond were not improved (61±12%). Placement of glass ionomer liner significantly improved the values of CM in all the sub-groups (78±9%, 72±10% and 77±10% for Single Bond, One Coat Self Etching Bond & Adper Easy Bond respectively) compared with no liner group. Placement of liners improved the values of 'continuous margin' in the gingival floor of the proximal cavities restored with composite resins using different bonding

  3. Evaluation of Skin Friction Drag for Liner Applications in Aircraft

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Jasinski, Christopher M.

    2016-01-01

    A parameter that is gaining significance in the evaluation of acoustic liner performance is the skin friction drag induced by air flow over the liner surface. Estimates vary widely regarding the amount of drag the liner induces relative to a smooth wall, from less than a 20% increase to nearly 100%, and parameters such as face sheet perforate hole diameter, percent open area, and sheet thickness are expected to figure prominently in the skin friction drag. Even a small increase in liner drag can impose an economic penalty, and current research is focused on developing 'low drag' liner concepts, with the goal being to approach the skin friction drag of a smooth wall. The issue of skin friction drag takes on greater significance as airframe designers investigate the feasibility of putting sound absorbing liners on the non-lifting surfaces of the wings and fuselage, for the purpose of reducing engine noise reflected and scattered toward observers on the ground. Researchers at the NASA Langley Research Center have embarked on investigations of liner skin friction drag with the aims of: developing a systematic drag measurement capability, establishing the drag of current liners, and developing liners that produce reduced drag without compromising acoustic performance. This paper discusses the experimental procedures that have been developed to calculate the drag coefficient based on the change in momentum thickness and the companion research program being carried out to measure the drag directly using a force balance. Liner samples that are evaluated include a solid wall with known roughness and conventional liners with perforated facesheets of varying hole diameter and percent open area.

  4. Diagnostics for the plasma liner experiment.

    PubMed

    Lynn, A G; Merritt, E; Gilmore, M; Hsu, S C; Witherspoon, F D; Cassibry, J T

    2010-10-01

    The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical "plasma liners" via merging high Mach number plasma jets to reach peak liner pressures of ∼0.1 Mbar using ∼1.5 MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n(i)∼10(16) cm(-3), T(e)≈T(i)∼1 eV at the plasma gun mouth to n(i)>10(19) cm(-3), T(e)≈T(i)∼0.5 keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.

  5. The photoionization mechanism of LINERs - Stellar and nonstellar

    NASA Technical Reports Server (NTRS)

    Ho, Luis C.; Filippenko, Alexei V.

    1993-01-01

    We present high quality spectroscopic observations of a sample of 14 LINERs. Starlight removal is achieved by the subtraction of a suitable absorption-line 'template' galaxy, allowing accurate measurements of emission lines. We use these line fluxes to examine the possible excitation mechanisms of LINERs. We suggest that LINERs with weak forbidden O I 6300-A emission may be H II regions photoionized by unusually hot O-type stars. LINERs with forbidden O I/H-alpha approximately greater than 1/6 may be powered by photoionization from a nonstellar continuum. This is supported by the detection of broad H-alpha emission, a correlation between line width and critical density, and pointlike X-ray emission in several of these objects.

  6. RETROSPECTIVE STUDY OF CIPP LINERS USED FOR REHABILITATION IN COLUMBUS, OHIO AND DENVER, COLORADO

    EPA Science Inventory

    Cured-in-place pipe (CIPP) has been successfully used for the rehabilitation of deteriorating wastewater pipes for nearly 30 years in the U.S. However, little quantitative data is available regarding the performance of these liners that can confirm their estimated design life. Wi...

  7. Evaluation of Novel Liner Concepts for Fan and Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Howerton, B. M.

    2016-01-01

    This paper presents a review of four novel liner concepts: soft vanes, over-the-rotor liners, external liners, and flap side-edge liners. A number of similarities in the design and evaluation of these concepts emerged during these investigations. Since these were the first attempts to study these particular liner concepts, there was limited information to guide the design process. In all cases, the target frequencies (or frequency range) were known, but the optimum acoustic impedance and optimum liner placement were typically not known. For these cases, the maximum available surface was used and a c-impedance was targeted based on the assumption the sound field impinges on the surface at normal incidence. This choice proved fruitful for every application. An impedance prediction model was used to design variable-depth liner configurations, and a graphical design code (ILIAD) was developed to aid in this process. The ability to build increasingly complex liner configurations via additive manufacturing was key, such that multiple designs could quickly be tested in a normal incidence impedance tube. The Two-Thickness Method was used to evaluate available bulk materials, such that bulk liners could also be considered for each application. These novel liner concepts provide sufficient noise reduction to warrant further investigations.

  8. High Thermal Conductivity NARloy-Z-Diamond Composite Combustion Chamber Liner For Advanced Rocket Engines

    NASA Technical Reports Server (NTRS)

    Bhat, Biliyar N.; Ellis, David; Singh, Jogender

    2014-01-01

    Advanced high thermal conductivity materials research conducted at NASA Marshall Space Flight Center (MSFC) with state of the art combustion chamber liner material NARloy-Z showed that its thermal conductivity can be increased significantly by adding diamond particles and sintering it at high temperatures. For instance, NARloy-Z containing 40 vol. percent diamond particles, sintered at 975C to full density by using the Field assisted Sintering Technology (FAST) showed 69 percent higher thermal conductivity than baseline NARloy-Z. Furthermore, NARloy-Z-40vol. percent D is 30 percent lighter than NARloy-Z and hence the density normalized thermal conductivity is 140 percent better. These attributes will improve the performance and life of the advanced rocket engines significantly. By one estimate, increased thermal conductivity will directly translate into increased turbopump power up to 2X and increased chamber pressure for improved thrust and ISP, resulting in an expected 20 percent improvement in engine performance. Follow on research is now being conducted to demonstrate the benefits of this high thermal conductivity NARloy-Z-D composite for combustion chamber liner applications in advanced rocket engines. The work consists of a) Optimizing the chemistry and heat treatment for NARloy-Z-D composite, b) Developing design properties (thermal and mechanical) for the optimized NARloy-Z-D, c) Fabrication of net shape subscale combustion chamber liner, and d) Hot fire testing of the liner for performance. FAST is used for consolidating and sintering NARlo-Z-D. The subscale cylindrical liner with built in channels for coolant flow is also fabricated near net shape using the FAST process. The liner will be assembled into a test rig and hot fire tested in the MSFC test facility to determine performance. This paper describes the development of this novel high thermal conductivity NARloy-Z-D composite material, and the advanced net shape technology to fabricate the combustion

  9. Suppression of Helmholtz resonance using inside acoustic liner

    NASA Astrophysics Data System (ADS)

    Hong, Zhiliang; Dai, Xiwen; Zhou, Nianfa; Sun, Xiaofeng; Jing, Xiaodong

    2014-08-01

    When a Helmholtz resonator is exposed to grazing flow, an unstable shear layer at the opening can cause the occurrence of acoustic resonance under appropriate conditions. In this paper, in order to suppress the flow-induced resonance, the effects of inside acoustic liners placed on the side wall or the bottom of a Helmholtz resonator are investigated. Based on the one-dimensional sound propagation theory, the time domain impedance model of a Helmholtz resonator with inside acoustic liner is derived, and then combined with a discrete vortex model the resonant behavior of the resonator under grazing flow is simulated. Besides, an experiment is conducted to validate the present model, showing significant reduction of the peak sound pressure level achieved by the use of the side-wall liners. And the simulation results match reasonably well with the experimental data. The present results reveal that the inside acoustic liner can not only absorb the resonant sound pressure, but also suppress the fluctuation motion of the shear layer over the opening of the resonator. In all, the impact of the acoustic liners is to dampen the instability of the flow-acoustic coupled system. This demonstrates that it is a convenient and effective method for suppressing Helmholtz resonance by using inside acoustic liner.

  10. Ecodesign of Liquid Fuel Tanks

    NASA Astrophysics Data System (ADS)

    Gicevska, Jana; Bazbauers, Gatis; Repele, Mara

    2011-01-01

    The subject of the study is a 10 litre liquid fuel tank made of metal and used for fuel storage and transportation. The study dealt with separate life cycle stages of this product, compared environmental impacts of similar fuel tanks made of metal and plastic, as well as analysed the product's end-of-life cycle stage, studying the waste treatment and disposal scenarios. The aim of this study was to find opportunities for improvement and to develop proposals for the ecodesign of 10 litre liquid fuel tank.

  11. Low-Speed Fan Noise Attenuation from a Foam-Metal Liner

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Jones, Michael G.

    2011-01-01

    A foam-metal liner for attenuation of fan noise was developed for and tested on a low-speed fan. This type of liner represents a significant advance over traditional liners, due to the possibility of placement in close proximity to the rotor. An advantage of placing treatment in this region is that the acoustic near field is modified, thereby inhibiting the noise-generation mechanism. This can result in higher attenuation levels than could be achieved by liners located in the nacelle inlet. In addition, foam-metal liners could potentially replace the fan rub strip and containment components, ultimately reducing engine components and thus weight, which can result in a systematic increase in noise reduction and engine performance. Foam-metal liners have the potential to reduce fan noise by 4 dB based on this study.

  12. Development of advanced materials composites for use as insulations for LH2 tanks

    NASA Technical Reports Server (NTRS)

    Lemons, C. R.; Salmassy, O. K.

    1973-01-01

    A study of thread-reinforced polyurethane foam and glass fabric liner, serving as internally bonded insulation for space shuttle LH2 tanks, is reported. Emphasis was placed on an insulation system capable of reentry and multiple reuse in the shuttle environment. The optimized manufacturing parameters associated with each element of the composite are established and the results, showing successful completion of subscale system evaluation tests using the shuttle flight environmental requirements, are given.

  13. FIELD VERIFICATION OF LINERS FROM SANITARY LANDFILLS

    EPA Science Inventory

    Liner specimens from three existing landfill sites were collected and examined to determine the changes in their physical properties over time and to validate data being developed through laboratory research. Samples examined included a 15-mil PVC liner from a sludge lagoon in Ne...

  14. Development of a Multifidelity Approach to Acoustic Liner Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.

    2017-01-01

    The use of acoustic liners has proven to be extremely effective in reducing aircraft engine fan noise transmission/radiation. However, the introduction of advanced fan designs and shorter engine nacelles has highlighted a need for novel acoustic liner designs that provide increased fan noise reduction over a broader frequency range. To achieve aggressive noise reduction goals, advanced broadband liner designs, such as zone liners and variable impedance liners, will likely depart from conventional uniform impedance configurations. Therefore, educing the impedance of these axial- and/or spanwise-variable impedance liners will require models that account for three-dimensional effects, thereby increasing computational expense. Thus, it would seem advantageous to investigate the use of multifidelity modeling approaches to impedance eduction for these advanced designs. This paper describes an extension of the use of the CDUCT-LaRC code to acoustic liner impedance eduction. The proposed approach is applied to a hardwall insert and conventional liner using simulated data. Educed values compare well with those educed using two extensively tested and validated approaches. The results are very promising and provide justification to further pursue the complementary use of CDUCT-LaRC with the currently used finite element codes to increase the efficiency of the eduction process for configurations involving three-dimensional effects.

  15. Development of Standardized Material Testing Protocols for Prosthetic Liners

    PubMed Central

    Cagle, John C.; Reinhall, Per G.; Hafner, Brian J.; Sanders, Joan E.

    2017-01-01

    A set of protocols was created to characterize prosthetic liners across six clinically relevant material properties. Properties included compressive elasticity, shear elasticity, tensile elasticity, volumetric elasticity, coefficient of friction (CoF), and thermal conductivity. Eighteen prosthetic liners representing the diverse range of commercial products were evaluated to create test procedures that maximized repeatability, minimized error, and provided clinically meaningful results. Shear and tensile elasticity test designs were augmented with finite element analysis (FEA) to optimize specimen geometries. Results showed that because of the wide range of available liner products, the compressive elasticity and tensile elasticity tests required two test maxima; samples were tested until they met either a strain-based or a stress-based maximum, whichever was reached first. The shear and tensile elasticity tests required that no cyclic conditioning be conducted because of limited endurance of the mounting adhesive with some liner materials. The coefficient of friction test was based on dynamic coefficient of friction, as it proved to be a more reliable measurement than static coefficient of friction. The volumetric elasticity test required that air be released beneath samples in the test chamber before testing. The thermal conductivity test best reflected the clinical environment when thermal grease was omitted and when liner samples were placed under pressure consistent with load bearing conditions. The developed procedures provide a standardized approach for evaluating liner products in the prosthetics industry. Test results can be used to improve clinical selection of liners for individual patients and guide development of new liner products. PMID:28233885

  16. HYDRAULIC CONDUCTIVITY OF THREE GEOSYNTHETIC CLAY LINERS

    EPA Science Inventory

    The hydraulic conductivity of three 2.9 m2 (32 sq ft) geosynthetic clay liners (GCLs) was measured. Tests were performed on individual sheets of the GCLs, on overlapped pieces of GCLs, and on composite liners consisting of a punctured geomembrane overlying a GCL. Hyd...

  17. Acoustic Liner for Turbomachinery Applications

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.; Sutliff, Daniel L.; Jones, Michael G.; Hebsur, Mohan G.

    2010-01-01

    The purpose of this innovation is to reduce aircraft noise in the communities surrounding airports by significantly attenuating the noise generated by the turbomachinery, and enhancing safety by providing a containment barrier for a blade failure. Acoustic liners are used in today's turbofan engines to reduce noise. The amount of noise reduction from an acoustic liner is a function of the treatment area, the liner design, and the material properties, and limited by the constraints of the nacelle or casement design. It is desirable to increase the effective area of the acoustic treatment to increase noise suppression. Modern turbofan engines use wide-chord rotor blades, which means there is considerable treatment area available over the rotor tip. Turbofan engines require containment over the rotors for protection from blade failure. Traditional methods use a material wrap such as Kevlar integrated with rub strips and sometimes metal layers (sandwiches). It is possible to substitute the soft rub-strip material with an open-cell metallic foam that provides noise-reduction benefits and a sacrificial material in the first layer of the containment system. An open-cell foam was evaluated that behaves like a bulk acoustic liner, serves as a tip rub strip, and can be integrated with a rotor containment system. Foams can be integrated with the fan-containment system to provide sufficient safety margins and increased noise attenuation. The major innovation is the integration of the foam with the containment.

  18. Impedance Eduction in Sound Fields With Peripherally Varying Liners and Flow

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Jones, M. G.

    2015-01-01

    A two-dimensional impedance eduction theory is extended to three-dimensional sound fields and peripherally varying duct liners. The approach is to first measure the acoustic pressure field at a series of flush-mounted wall microphones located around the periphery of the flow duct. The numerical solution for the acoustic pressure field at these microphones is also obtained by solving the three-dimensional convected Helmholtz equation using the finite element method. A quadratic objective function based on the difference between the measured and finite element solution is constructed and the unknown impedance function is obtained by minimizing this objective function. Impedance spectra educed for two uniform-structure liners (a wire-mesh and a conventional liner) and a hard-soft-hard peripherally varying liner (for which the soft segment is that of the conventional liner) are presented. Results are presented at three mean flow Mach numbers and fourteen sound source frequencies. The impedance spectra of the uniform-structure liners are also computed using a two-dimensional impedance eduction theory. The primary conclusions of the study are: 1) when measured data is used with the uniform-structure liners, the three-dimensional theory reproduces the same impedance spectra as the two-dimensional theory except for frequencies corresponding to very low or very high liner attenuation; and 2) good agreement between the educed impedance spectra of the uniform structure conventional liner and the soft segment of the peripherally varying liner is obtained.

  19. Evaluation of Parallel-Element, Variable-Impedance, Broadband Acoustic Liner Concepts

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Howerton, Brian M.; Ayle, Earl

    2012-01-01

    Recent trends in aircraft engine design have highlighted the need for acoustic liners that provide broadband sound absorption with reduced liner thickness. Three such liner concepts are evaluated using the NASA normal incidence tube. Two concepts employ additive manufacturing techniques to fabricate liners with variable chamber depths. The first relies on scrubbing losses within narrow chambers to provide acoustic resistance necessary for sound absorption. The second employs wide chambers that provide minimal resistance, and relies on a perforated sheet to provide acoustic resistance. The variable-depth chambers used in both concepts result in reactance spectra near zero. The third liner concept employs mesh-caps (resistive sheets) embedded at variable depths within adjacent honeycomb chambers to achieve a desired impedance spectrum. Each of these liner concepts is suitable for use as a broadband sound absorber design, and a transmission line model is presented that provides good comparison with their respective acoustic impedance spectra. This model can therefore be used to design acoustic liners to accurately achieve selected impedance spectra. Finally, the effects of increasing the perforated facesheet thickness are demonstrated, and the validity of prediction models based on lumped element and wave propagation approaches is investigated. The lumped element model compares favorably with measured results for liners with thin facesheets, but the wave propagation model provides good comparisons for a wide range of facesheet thicknesses.

  20. Energy transfer through a multi-layer liner for shaped charges

    DOEpatents

    Skolnick, Saul; Goodman, Albert

    1985-01-01

    This invention relates to the determination of parameters for selecting materials for use as liners in shaped charges to transfer the greatest amount of energy to the explosive jet. Multi-layer liners constructed of metal in shaped charges for oil well perforators or other applications are selected in accordance with the invention to maximize the penetrating effect of the explosive jet by reference to four parameters: (1) Adjusting the explosive charge to liner mass ratio to achieve a balance between the amount of explosive used in a shaped charge and the areal density of the liner material; (2) Adjusting the ductility of each layer of a multi-layer liner to enhance the formation of a longer energy jet; (3) Buffering the intermediate layers of a multi-layer liner by varying the properties of each layer, e.g., composition, thickness, ductility, acoustic impedance and areal density, to protect the final inside layer of high density material from shattering upon impact of the explosive force and, instead, flow smoothly into a jet; and (4) Adjusting the impedance of the layers in a liner to enhance the transmission and reduce the reflection of explosive energy across the interface between layers.

  1. Hard X-Ray Emission and the Ionizing Source in LINERs

    NASA Technical Reports Server (NTRS)

    Terashima, Yuichi; Ho, Luis C.; Ptak, Andrew F.

    2000-01-01

    We report X-ray fluxes in the 2-10 keV band from LINERs (low-ionization nuclear emission-line regions) and low-luminosity Seyfert galaxies obtained with the ASCA satellite. Observed X-ray luminosities are in the range between 4 x 10(exp 39) and 5 x 10(exp 41) ergs/s, which are significantly smaller than that of the "classical" low-luminosity Seyfert 1 galaxy NGC 4051. We found that X-ray luminosities in 2-10 keV of LINERs with broad H.alpha emission in their optical spectra (LINER 1s) are proportional to their Ha luminosities. This correlation strongly supports the hypothesis that the dominant ionizing source in LINER 1s is photoionization by hard photons from low-luminosity AGNs. On the other hand, the X-ray luminosities of most LINERs without broad H.alpha emission (LINER 2s) in our sample are lower than LINER 1s at a given H.alpha luminosity. The observed X-ray luminosities in these objects are insufficient to power their H.alpha luminosities, suggesting that their primary ionizing source is other than an AGN, or that an AGN, if present, is obscured even at energies above 2 keV.

  2. A Comparative Study of Four Impedance Eduction Methodologies Using Several Test Liners

    NASA Technical Reports Server (NTRS)

    Watson, Willie R.; Jones, Michael G.

    2013-01-01

    A comparative study of four commonly used impedance eduction methods is presented for a range of liner structures and test conditions. Two of the methods are restricted to uniform flow while the other two accommodate both uniform and boundary layer flows. Measurements on five liner structures (a rigid-wall insert, a ceramic tubular liner, a wire mesh liner, a low porosity conventional liner, and a high porosity conventional liner) are obtained using the NASA Langley Grazing Flow Impedance Tube. The educed impedance of each liner is presented for forty-two test conditions (three Mach numbers and fourteen frequencies). In addition, the effects of moving the acoustic source from upstream to downstream and the refractive effects of the mean boundary layer on the wire mesh liner are investigated. The primary conclusions of the study are that: (1) more accurate results are obtained for the upstream source, (2) the uniform flow methods produce nearly identical impedance spectra at and below Mach 0.3 but significant scatter in the educed impedance occurs at the higher Mach number, (3) there is better agreement in educed impedance among the methods for the conventional liners than for the rigid-wall insert, ceramic, or wire mesh liner, and (4) the refractive effects of the mean boundary layer on the educed impedance of the wire mesh liner are generally small except at Mach 0.5.

  3. Effects of Liner Length and Attenuation on NASA Langley Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.

    2016-01-01

    This study explores the effects of liner length and attenuation on the CHE (convected Helmholtz equation) impedance eduction method, in which the surface impedance of an acoustic liner is inferred through an iterative process based on repeated solutions to the convected Helmholtz equation. Wire mesh-over-honeycomb and perforate-over-honeycomb acoustic liners are tested in the NASA Langley Grazing Flow Impedance Tube, and the resultant data are processed using two impedance eduction methods. The first is the CHE method, and the second is a direct method (labeled the KT method) that uses the Kumaresan and Tufts algorithm to compute the impedance directly. The CHE method has been extensively used for acoustic liner evaluation, but experiences anomalous behavior under some test conditions. It is postulated that the anomalies are related to the liner length and/or attenuation. Since the KT method only employs data measured over the length of the liner, it is expected to be unaffected by liner length. A comparison of results achieved with the two impedance eduction methods is used to explore the interactive effects of liner length and attenuation on the CHE impedance eduction method.

  4. A Method for Optimizing Non-Axisymmetric Liners for Multimodal Sound Sources

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Jones, M. G.; Parrott, T. L.; Sobieski, J.

    2002-01-01

    Central processor unit times and memory requirements for a commonly used solver are compared to that of a state-of-the-art, parallel, sparse solver. The sparse solver is then used in conjunction with three constrained optimization methodologies to assess the relative merits of non-axisymmetric versus axisymmetric liner concepts for improving liner acoustic suppression. This assessment is performed with a multimodal noise source (with equal mode amplitudes and phases) in a finite-length rectangular duct without flow. The sparse solver is found to reduce memory requirements by a factor of five and central processing time by a factor of eleven when compared with the commonly used solver. Results show that the optimum impedance of the uniform liner is dominated by the least attenuated mode, whose attenuation is maximized by the Cremer optimum impedance. An optimized, four-segmented liner with impedance segments in a checkerboard arrangement is found to be inferior to an optimized spanwise segmented liner. This optimized spanwise segmented liner is shown to attenuate substantially more sound than the optimized uniform liner and tends to be more effective at the higher frequencies. The most important result of this study is the discovery that when optimized, a spanwise segmented liner with two segments gives attenuations equal to or substantially greater than an optimized axially segmented liner with the same number of segments.

  5. Liner Optimization Studies Using the Ducted Fan Noise Prediction Code TBIEM3D

    NASA Technical Reports Server (NTRS)

    Dunn, M. H.; Farassat, F.

    1998-01-01

    In this paper we demonstrate the usefulness of the ducted fan noise prediction code TBIEM3D as a liner optimization design tool. Boundary conditions on the interior duct wall allow for hard walls or a locally reacting liner with axially segmented, circumferentially uniform impedance. Two liner optimization studies are considered in which farfield noise attenuation due to the presence of a liner is maximized by adjusting the liner impedance. In the first example, the dependence of optimal liner impedance on frequency and liner length is examined. Results show that both the optimal impedance and attenuation levels are significantly influenced by liner length and frequency. In the second example, TBIEM3D is used to compare radiated sound pressure levels between optimal and non-optimal liner cases at conditions designed to simulate take-off. It is shown that significant noise reduction is achieved for most of the sound field by selecting the optimal or near optimal liner impedance. Our results also indicate that there is relatively large region of the impedance plane over which optimal or near optimal liner behavior is attainable. This is an important conclusion for the designer since there are variations in liner characteristics due to manufacturing imprecisions.

  6. Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees

    NASA Astrophysics Data System (ADS)

    Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan

    2017-08-01

    This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction.

  7. Comparison of Acoustic Impedance Eduction Techniques for Locally-Reacting Liners

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Parrott, T. L.; Watson, W. R.

    2003-01-01

    Typical acoustic liners used in current aircraft inlets and aft-fan ducts consist of some type of perforated facesheet bonded to a honeycomb core. A number of techniques for determining the acoustic impedance of these locallyreacting liners have been developed over the last five decades. In addition, a number of models have been developed to predict the acoustic impedance of locallyreacting liners in the presence of grazing flow, and to use that information together with aeroacoustic propagation codes to assess the noise absorption provided by these liners. These prediction models have incorporated the results from databases acquired with specific impedance eduction techniques. Thus, while these prediction models are acceptable for liners that are similar to those tested in these databases, their application to new liner configurations must be viewed with caution. The primary purpose of this paper is to provide a comparison of impedance eduction techniques that have been implemented at various aerospace research laboratories in the United States (NASA Langley Research Center, General Electric Aircraft Engines, B. F. Goodrich and Boeing). A secondary purpose is to provide data for liner configurations that extend the porosity range beyond that which has been previously used in common aircraft engine nacelles. Two sets of liners were designed to study the effects of three parameters: perforate hole diameter, facesheet thickness and porosity. These two sets of liners were constructed for testing in each of the laboratories listed above. The first set of liners was designed to fit into the NASA Langley and Boeing test facilities. The second set was designed to fit into the General Electric Aircraft Engines and B. F. Goodrich test facilities. By using the same parent material, both sets of liners were identical to within the limits of material and fabrication variability. Baseline data were obtained in the normal incidence impedance tubes at NASA Langley and B. F

  8. RQL Sector Rig Testing of SiC/SiC Combustor Liners

    NASA Technical Reports Server (NTRS)

    Verrilli, Michael J.; Martin, Lisa C.; Brewer, David N.

    2002-01-01

    Combustor liners, manufactured from silicon carbide fiber-reinforced silicon carbide (SiC/SiC) were tested for 260 hr using a simulated gas turbine engine cycle. This report documents the results of the last 56 hr of testing. Damage occurred in one of the six different components that make up the combustor liner set, the rich zone liner. Cracks in the rich zone liner initiated at the leading edge due to stresses resulting from the component attachment configuration. Thin film thermocouples and fiber optic pyrometers were used to measure the rich zone liner's temperature and these results are reported.

  9. Elastomer liners for geothermal tubulars Y267 EPDM Liner Program:

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

    Hirasuna, A.R.; Davis, D.L.; Flickinger, J.E.

    1987-12-01

    The elastomer, Y267 EPDM, has been identified as a hydrothermally stable material which can operate at temperatures in excess of 320/sup 0/C. The goal of the Y267 Liner Program was to demonstrate the feasibility of using this material as a liner for mild steel tubulars to prevent or mitigate corrosion. If successful, the usage of EPDM lined pipe by the geothermal community may have a significant impact on operating costs and serve as a viable alternative to the use of alloyed tubulars. Tooling procedures were developed under this program to mold a 0.64 cm (0.25'') thick Y267 EPDM liner intomore » a tubular test section 61 cm (2') in length and 19.1 cm (7.5'') in diameter (ID). A successful effort was made to identify a potential coupling agent to be used to bond the elastomer to the steel tubular wall. This agent was found to withstand the processing conditions associated with curing the elastomer at 288/sup 0/C and to retain a significant level of adhesive strength following hydrothermal testing in a synthetic brine at 260/sup 0/C for a period of 166 hours. Bonding tests were conducted on specimens of mild carbon steel and several alloys including Hastelloy C-276. An objective of the program was to field test the lined section of pipe mentioned above at a geothermal facility in the Imperial Valley. Though a test was conducted, problems encountered during the lining operation precluded an encouraging outcome. The results of the field demonstration were inconclusive. 6 refs., 13 figs., 13 tabs« less

  10. Drag Measurements of Porous Plate Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Wolter, John D.

    2005-01-01

    This paper presents the results of direct drag measurements on a variety of porous plate acoustic liners. The existing literature describes numerous studies of drag on porous walls with injection or suction, but relatively few of drag on porous plates with neither injection nor suction. Furthermore, the porosity of the porous plate in existing studies is much lower than typically used in acoustic liners. In the present work, the acoustic liners consisted of a perforated face sheet covering a bulk acoustic absorber material. Factors that were varied in the experiment were hole diameter, hole pattern, face sheet thickness, bulk material type, and size of the gap (if any) between the face sheet and the absorber material.

  11. Experimental Impedance of Single Liner Elements with Bias Flow

    NASA Technical Reports Server (NTRS)

    Follet, J. I.; Betts, J. F.; Kelly, Jeffrey J.; Thomas, Russell H.

    2000-01-01

    An experimental investigation was conducted to generate a high quality database, from which the effects of a mean bias flow on the acoustic impedance of lumped-element single-degree-of-freedom liners was determined. Acoustic impedance measurements were made using the standard two-microphone method in the NASA Langley Normal Incidence Tube. Each liner consisted of a perforated sheet with a constant-area cavity. Liner resistance was shown to increase and to become less frequency and sound pressure level dependent as the bias flow was increased. The resistance was also consistently lower for a negative bias flow (suction) than for a positive bias flow (blowing) of equal magnitude. The slope of the liner reactance decreased with increased flow.

  12. Flow Duct Data for Validation of Acoustic Liner Codes for Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Ahuja, K. K.; Munro, Scott; Gaeta, R. J., Jr.

    2000-01-01

    The objective of the study reported here was to acquire acoustic and flow data with hard and lined duct wall duct sections for validation of a liner prediction code being developed at NASA LaRC. Both the mean flowfield and acoustic flowfields were determined in a cross-plane of the rectangular duct. A flow duct facility with acoustic drivers connected to a rectangular (4.7 x 2.0 inch) source section and a linear acoustic liner mounted downstream of the source section was used in this study. The liner section was designed to allow liner materials to be placed on all 4 walls of the duct. The test liner was of the locally-reacting type and was made from a ceramic material. The material, consisting of a tubular structure, was provided by NASA LaRC. The liner was approximately 8.89 cm (3.5 inches) thick. For the current study, only the two "short" sides of the duct were lined with liner material. The other two sides were hard walls. Two especially built instrumentation sections were attached on either sides of the liner section to allow acoustic and flow measurements to be made upstream and downstream of the liner. The two instrumentation duct sections were built to allow measurement of acoustic and flow properties at planes perpendicular to flow upstream and downstream of the liner section. The instrumentation section was also designed to provide a streamwise gradient in acoustic (complex) pressure from which the acoustic particle velocity, needed for the model validation, can be computed. Flow measurements included pressure, temperature, and velocity profiles upstream of the liner section. The in-flow sound pressure levels and phases were obtained with a microphone probe equipped with a nose cone in two cross planes upstream of the liner and two cross plane downstream of the liner. In addition to the acoustic measurements at the cross planes. axial centerline acoustic data was acquired using an axially traversing microphone probe which was traversed from a location

  13. Further Development and Assessment of a Broadband Liner Optimization Process

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.

    2016-01-01

    The utilization of advanced fan designs (including higher bypass ratios) and shorter engine nacelles has highlighted a need for increased fan noise reduction over a broader frequency range. Thus, improved broadband liner designs must account for these constraints and, where applicable, take advantage of advanced manufacturing techniques that have opened new possibilities for novel configurations. This work focuses on the use of an established broadband acoustic liner optimization process to design a variable-depth, multi-degree of freedom liner for a high speed fan. Specifically, in-duct attenuation predictions with a statistical source model are used to obtain optimum impedance spectra over the conditions of interest. The predicted optimum impedance information is then used with acoustic liner modeling tools to design a liner aimed at producing impedance spectra that most closely match the predicted optimum values. The multi-degree of freedom design is carried through design, fabrication, and testing. In-duct attenuation predictions compare well with measured data and the multi-degree of freedom liner is shown to outperform a more conventional liner over a range of flow conditions. These promising results provide further confidence in the design tool, as well as the enhancements made to the overall design process.

  14. Construction and performance of a long-term earthen liner experiment

    USGS Publications Warehouse

    Cartwright, Keros; Krapac, Ivan G.; Bonaparte, Rudolph

    1990-01-01

    In land burial schemes, compacted soil barriers with low hydraulic conductivity are commonly used in cover and liner systems to control the movement of liquids and prevent groundwater contamination. An experimental liner measuring 8 x 15 x 0.9 m was constructed with design criteria and equipment to simulate construction of soil liners built at waste disposal facilities. The surface of the liner was flooded with a 29.5 cm deep pond on April 12, 1988. Infiltration of water into the liner has been monitored for two years using 4 large-ring (1.5 m OD) and 32 small-ring (0.28 m OD) infiltrometers, and a water-balance that accounts for total infiltration and evaporation. Average long-term infiltration fluxes based on two years of monitoring are 5.8 x 10-9 cm/s, 6.0 x 10-8 cm/s and 5.6 x 10-8 for the large-ring, small-ring, and water-balance data, respectively. The saturated hydraulic conductivity of the liner based on small-ring data, estimated using Darcy's Law and the Green-Ampt Approximation, is 3 x 10-8 and 4 x 10-8 cm/s, respectively. All sets of data indicate that the liner's performance exceed that which is required by the U.S. EPA.

  15. Optimization of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Schiller, N. H.; Born, J. C.

    2016-01-01

    This paper employs three acoustic propagation codes to explore variable-depth liner configurations for the NASA Langley Grazing Flow Impedance Tube (GFIT). The initial study demonstrates that a variable impedance can acceptably be treated as a uniform impedance if the spatial extent over which this variable impedance occurs is less than one-third of a wavelength of the incident sound. A constrained optimization study is used to design a variable-depth liner and to select an optimization metric. It also provides insight regarding how much attenuation can be achieved with variable-depth liners. Another optimization study is used to design a liner with much finer chamber depth resolution for the Mach 0.0 and 0.3 test conditions. Two liners are designed based on spatial rearrangement of chambers from this liner to determine whether the order is critical. Propagation code predictions suggest this is not the case. Both liners are fabricated via additive manufacturing and tested in the GFIT for the Mach 0.0 condition. Predicted and measured attenuations compare favorably across the full frequency range. These results clearly suggest that the chambers can be arranged in any order, thus offering the potential for innovative liner designs to minimize depth and weight.

  16. Modeling of Broadband Liners Applied to the Advanced Noise Control Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.

    2015-01-01

    The broadband component of fan noise has grown in relevance with an increase in bypass ratio and incorporation of advanced fan designs. Therefore, while the attenuation of fan tones remains a major factor in engine nacelle acoustic liner design, the simultaneous reduction of broadband fan noise levels has received increased interest. As such, a previous investigation focused on improvements to an established broadband acoustic liner optimization process using the Advanced Noise Control Fan (ANCF) rig as a demonstrator. Constant-depth, double-degree of freedom and variable-depth, multi-degree of freedom liner designs were carried through design, fabrication, and testing. This paper addresses a number of areas for further research identified in the initial assessment of the ANCF study. Specifically, incident source specification and uncertainty in some aspects of the predicted liner impedances are addressed. This information is incorporated in updated predictions of the liner performance and comparisons with measurement are greatly improved. Results illustrate the value of the design process in concurrently evaluating the relative costs/benefits of various liner designs. This study also provides further confidence in the integrated use of duct acoustic propagation/radiation and liner modeling tools in the design and evaluation of novel broadband liner concepts for complex engine configurations.

  17. Status of Duct Liner Technology for Application to Aircraft Engine Nacelles

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Jones, Michael G.; Watson, Willie R.

    2005-01-01

    Grazing flows and high acoustic intensities impose unusual design requirements on acoustic liner treatments used in aircraft engine nacelles. Increased sound absorption efficiency (requiring increased accuracy of liner impedance specification) is particularly critical in the face of ever decreasing nacelle wall area available for liner treatments in modern, high-bypass ratio engines. This paper reviews the strategy developed at Langley Research Center for achieving a robust measurement technology that is crucial for validating impedance models for aircraft liners. Specifically, the paper describes the current status of computational and data acquisition technologies for reducing impedance in a flow duct. Comparisons of reduced impedances for a "validation liner" using 1980's and 2000's measurement technology are consistent, but show significant deviations (up to 0.5 c exclusive of liner anti-resonance region) from a first principles impedance prediction model as grazing flow centerline Mach numbers increase up to 0.5. The deviations, in part, are believed related to uncertainty in the choice of grazing flow parameters (e.g. cross-section averaged, core-flow averaged, or centerline Mach number?). Also, there may be an issue with incorporating the impedance discontinuities corresponding to the hard wall to liner interface (i.e. leading and trailing edge of test liner) within the discretized finite element model.

  18. Computer method for design of acoustic liners for turbofan engines

    NASA Technical Reports Server (NTRS)

    Minner, G. L.; Rice, E. J.

    1976-01-01

    A design package is presented for the specification of acoustic liners for turbofans. An estimate of the noise generation was made based on modifications of existing noise correlations, for which the inputs are basic fan aerodynamic design variables. The method does not predict multiple pure tones. A target attenuation spectrum was calculated which was the difference between the estimated generation spectrum and a flat annoyance-weighted goal attenuated spectrum. The target spectrum was combined with a knowledge of acoustic liner performance as a function of the liner design variables to specify the acoustic design. The liner design method at present is limited to annular duct configurations. The detailed structure of the liner was specified by combining the required impedance (which is a result of the previous step) with a mathematical model relating impedance to the detailed structure. The design procedure was developed for a liner constructed of perforated sheet placed over honeycomb backing cavities. A sample calculation was carried through in order to demonstrate the design procedure, and experimental results presented show good agreement with the calculated results of the method.

  19. High-temperature combustor liner tests in structural component response test facility

    NASA Technical Reports Server (NTRS)

    Moorhead, Paul E.

    1988-01-01

    Jet engine combustor liners were tested in the structural component response facility at NASA Lewis. In this facility combustor liners were thermally cycled to simulate a flight envelope of takeoff, cruise, and return to idle. Temperatures were measured with both thermocouples and an infrared thermal imaging system. A conventional stacked-ring louvered combustor liner developed a crack at 1603 cycles. This test was discontinued after 1728 cycles because of distortion of the liner. A segmented or float wall combustor liner tested at the same heat flux showed no significant change after 1600 cycles. Changes are being made in the facility to allow higher temperatures.

  20. Investigation of Liner Characteristics in the NASA Langley Curved Duct Test Rig

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Watson, Willie R.; Jones, Michael G.

    2007-01-01

    The Curved Duct Test Rig (CDTR), which is designed to investigate propagation of sound in a duct with flow, has been developed at NASA Langley Research Center. The duct incorporates an adaptive control system to generate a tone in the duct at a specific frequency with a target Sound Pressure Level and a target mode shape. The size of the duct, the ability to isolate higher order modes, and the ability to modify the duct configuration make this rig unique among experimental duct acoustics facilities. An experiment is described in which the facility performance is evaluated by measuring the sound attenuation by a sample duct liner. The liner sample comprises one wall of the liner test section. Sound in tones from 500 to 2400 Hz, with modes that are parallel to the liner surface of order 0 to 5, and that are normal to the liner surface of order 0 to 2, can be generated incident on the liner test section. Tests are performed in which sound is generated without axial flow in the duct and with flow at a Mach number of 0.275. The attenuation of the liner is determined by comparing the sound power in a hard wall section downstream of the liner test section to the sound power in a hard wall section upstream of the liner test section. These experimentally determined attenuations are compared to numerically determined attenuations calculated by means of a finite element analysis code. The code incorporates liner impedance values educed from measured data from the NASA Langley Grazing Incidence Tube, a test rig that is used for investigating liner performance with flow and with (0,0) mode incident grazing. The analytical and experimental results compare favorably, indicating the validity of the finite element method and demonstrating that finite element prediction tools can be used together with experiment to characterize the liner attenuation.

  1. Long-term behavior of water content and density in an earthen liner

    USGS Publications Warehouse

    Frank, T.E.; Krapac, I.G.; Stark, T.D.; Strack, G.D.

    2005-01-01

    An extensively instrumented compacted earthen liner was constructed at the Illinois State Geological Survey facility in Champaign, III. in 1987. A pond of water 0.31 m deep was maintained on top of the 7.3 m ?? 14.6 m ?? 0.9 m thick liner for 14 years. One of the goals of the project was to evaluate the long-term performance of a compacted earthen liner by monitoring the long-term changes in water content and density. The water content of the earthen liner showed no trend with depth or time. The liner density remained essentially constant from construction through excavation in 2002. The liner did not become fully saturated. Upon excavation of the liner, the degree of saturation was 80.0??6.3% after 14 years of ponding under a hydraulic head of 0.31 m. The results imply that properly designed and constructed earthen liners may reduce the possibility of pollutants leaching from municipal solid waste containment facilities by remaining partially saturated for years and maintaining the placement density. Journal of Geotechnical and Geoenvironmental Engineering ?? ASCE.

  2. Boundary layer effects on liners for aircraft engines

    NASA Astrophysics Data System (ADS)

    Gabard, Gwénaël

    2016-10-01

    The performance of acoustic treatments installed on aircraft engines is strongly influenced by the boundary layer of the grazing flow on the surface of the liner. The parametric study presented in this paper illustrates the extent of this effect and identifies when it is significant. The acoustic modes of a circular duct with flow are calculated using a finite difference method. The parameters are representative of the flow conditions, liners and sound fields found in current turbofan engines. Both the intake and bypass ducts are considered. Results show that there is a complex interplay between the boundary layer thickness, the direction of propagation and the liner impedance and that the boundary layer can have a strong impact on liner performance for typical configurations (including changes of the order of 30 dB on the attenuation of modes associated with tonal fan noise). A modified impedance condition including the effect of a small but finite boundary layer thickness is considered and compared to the standard Myers condition based on an infinitely thin boundary layer. We show how this impedance condition can be implemented in a mode calculation method by introducing auxiliary variables. This condition is able to capture the trends associated with the boundary layer effects and in most cases provides improved predictions of liner performance.

  3. Evaluation of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2015-01-01

    This paper explores the effects of variable-depth geometry on the amount of noise reduction that can be achieved with acoustic liners. Results for two variable-depth liners tested in the NASA Langley Grazing Flow Impedance Tube demonstrate significant broadband noise reduction. An impedance prediction model is combined with two propagation codes to predict corresponding sound pressure level profiles over the length of the Grazing Flow Impedance Tube. The comparison of measured and predicted sound pressure level profiles is sufficiently favorable to support use of these tools for investigation of a number of proposed variable-depth liner configurations. Predicted sound pressure level profiles for these proposed configurations reveal a number of interesting features. Liner orientation clearly affects the sound pressure level profile over the length of the liner, but the effect on the total attenuation is less pronounced. The axial extent of attenuation at an individual frequency continues well beyond the location where the liner depth is optimally tuned to the quarter-wavelength of that frequency. The sound pressure level profile is significantly affected by the way in which variable-depth segments are distributed over the length of the liner. Given the broadband noise reduction capability for these liner configurations, further development of impedance prediction models and propagation codes specifically tuned for this application is warranted.

  4. CONSTRUCTION, MONITORING, AND PERFORMANCE OF TWO SOIL LINERS

    EPA Science Inventory

    A prototype soil liner and a field-scale soil liner were constructed to test whether compacted soil barrier systems could be built to meet the standard set by the U.S. Environmental Protection Agency (EPA) for saturated hydraulic conductivity (< 1 x 10'7 cm/s). In situ ponded inf...

  5. Advanced Computational and Experimental Techniques for Nacelle Liner Performance Evaluation

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Jones, Michael G.; Brown, Martha C.; Nark, Douglas

    2009-01-01

    The Curved Duct Test Rig (CDTR) has been developed to investigate sound propagation through a duct of size comparable to the aft bypass duct of typical aircraft engines. The axial dimension of the bypass duct is often curved and this geometric characteristic is captured in the CDTR. The semiannular bypass duct is simulated by a rectangular test section in which the height corresponds to the circumferential dimension and the width corresponds to the radial dimension. The liner samples are perforate over honeycomb core and are installed on the side walls of the test section. The top and bottom surfaces of the test section are acoustically rigid to simulate a hard wall bifurcation or pylon. A unique feature of the CDTR is the control system that generates sound incident on the liner test section in specific modes. Uniform air flow, at ambient temperature and flow speed Mach 0.275, is introduced through the duct. Experiments to investigate configuration effects such as curvature along the flow path on the acoustic performance of a sample liner are performed in the CDTR and reported in this paper. Combinations of treated and acoustically rigid side walls are investigated. The scattering of modes of the incident wave, both by the curvature and by the asymmetry of wall treatment, is demonstrated in the experimental results. The effect that mode scattering has on total acoustic effectiveness of the liner treatment is also shown. Comparisons of measured liner attenuation with numerical results predicted by an analytic model based on the parabolic approximation to the convected Helmholtz equation are reported. The spectra of attenuation produced by the analytic model are similar to experimental results for both walls treated, straight and curved flow path, with plane wave and higher order modes incident. The numerical model is used to define the optimized resistance and reactance of a liner that significantly improves liner attenuation in the frequency range 1900-2400 Hz. A

  6. Optical fiber Bragg grating-instrumented silicone liner for interface pressure measurement within prosthetic sockets of lower-limb amputees.

    PubMed

    Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan

    2017-08-01

    This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  7. Evaluating the accuracy of wear formulae for acetabular cup liners.

    PubMed

    Wu, James Shih-Shyn; Hsu, Shu-Ling; Chen, Jian-Horng

    2010-02-01

    This study proposes two methods for exploring the wear volume of a worn liner. The first method is a numerical method, in which SolidWorks software is used to create models of the worn out regions of liners at various wear directions and depths. The second method is an experimental one, in which a machining center is used to mill polyoxymethylene to manufacture worn and unworn liner models, then the volumes of the models are measured. The results show that the SolidWorks software is a good tool for presenting the wear pattern and volume of a worn liner. The formula provided by Ilchmann is the most suitable for computing liner volume loss, but is not accurate enough. This study suggests that a more accurate wear formula is required. This is crucial for accurate evaluation of the performance of hip components implanted in patients, as well as for designing new hip components.

  8. Demonstration of a wireless, self-powered, electroacoustic liner system.

    PubMed

    Phipps, Alex; Liu, Fei; Cattafesta, Louis; Sheplak, Mark; Nishida, Toshikazu

    2009-02-01

    This paper demonstrates the system operation of a self-powered active liner for the suppression of aircraft engine noise. The fundamental element of the active liner system is an electromechanical Helmholtz resonator (EMHR), which consists of a Helmholtz resonator with one of its rigid walls replaced with a circular piezoceramic composite plate. For this system demonstration, two EMHR elements are used, one for acoustic impedance tuning and one for energy harvesting. The EMHR used for acoustic impedance tuning is shunted with a variable resistive load, while the EMHR used for energy harvesting is shunted to a flyback power converter and storage element. The desired acoustic impedance conditions are determined externally, and wirelessly transmitted to the liner system. The power for the receiver and the impedance tuning circuitry in the liner are supplied by the harvested energy. Tuning of the active liner is demonstrated at three different sound pressure levels (148, 151, and 153 dB) in order to show the robustness of the energy harvesting and storage system. An acoustic tuning range of approximately 200 Hz is demonstrated for each of the three available power levels.

  9. Shaped Charge Liner Materials: Resources, Processes, Properties, Costs, and Applications

    DTIC Science & Technology

    1991-02-01

    SUBTITLE 5. FUNDING NUMBERS Shaped Charge Liner Materials: Resources, Processes, Properties, Costs, and Applications 2 6. AUTHOC Steven M. Buc 7...summaries of the mineral availability, Cq prmarymetal refinement processeb, material costs in raw form and as finished shaped charge liners , relevant... liner materials. 94-11479 gI 14, SUBJECT TERMS iSt NUMBER OF PAGIS 13chrg wrhad :xplosively formed penetrators material R. PRCE COEV" processing

  10. Experimental Evaluation of Acoustic Engine Liner Models Developed with COMSOL Multiphysics

    NASA Technical Reports Server (NTRS)

    Schiller, Noah H.; Jones, Michael G.; Bertolucci, Brandon

    2017-01-01

    Accurate modeling tools are needed to design new engine liners capable of reducing aircraft noise. The purpose of this study is to determine if a commercially-available finite element package, COMSOL Multiphysics, can be used to accurately model a range of different acoustic engine liner designs, and in the process, collect and document a benchmark dataset that can be used in both current and future code evaluation activities. To achieve these goals, a variety of liner samples, ranging from conventional perforate-over-honeycomb to extended-reaction designs, were installed in one wall of the grazing flow impedance tube at the NASA Langley Research Center. The liners were exposed to high sound pressure levels and grazing flow, and the effect of the liner on the sound field in the flow duct was measured. These measurements were then compared with predictions. While this report only includes comparisons for a subset of the configurations, the full database of all measurements and predictions is available in electronic format upon request. The results demonstrate that both conventional perforate-over-honeycomb and extended-reaction liners can be accurately modeled using COMSOL. Therefore, this modeling tool can be used with confidence to supplement the current suite of acoustic propagation codes, and ultimately develop new acoustic engine liners designed to reduce aircraft noise.

  11. Survivorship of Total Hip Joint Replacements Following Isolated Liner Exchange for Wear.

    PubMed

    Vadei, Leone; Kieser, David C; Frampton, Chris; Hooper, Gary

    2017-11-01

    Liner exchange for articular component wear in total hip joint replacements (THJRs) is a common procedure, often thought to be benign with reliable outcomes. Recent studies, however, suggest high failure rates of liner exchange revisions with significant complications. The primary aim of this study was, therefore, to analyze the survivorship of isolated liner exchange for articular component wear, and secondarily to assess the influence of patient demographics (gender, age, and American Society of Anaesthesiologists [ASA] ratings) on rerevisions following isolated liner exchange for wear. A retrospective review of the 15-year New Zealand Joint Registry (1999-2014) was performed, analyzing the outcomes of isolated liner exchange for articular component wear. The survivorship as defined as rerevision with component exchange was determined and 10-year Kaplan-Meier survivorship curves were constructed. These revision rates were compared to age, gender, and ASA rating groups using a log-rank test. The 10-year survivorship of THJR following liner exchange revision for liner wear was 75.3%. If a rerevision was required, the median time to rerevision was 1.33 years with a rerevision rate of 3.33 per 100 component years (95% confidence interval 2.68-4.08/100 component years). The principle reasons for rerevision were dislocation (48.4%) and acetabular component loosening (20.9%). There was no statistically significant difference in rerevision rates based on gender, age categories, or ASA scores. THJR isolated liner exchange for liner wear is not a benign procedure with a survivorship of 75.3% at 10 years. Surgeons contemplating liner exchange revisions should be cognisant of this risk and should adequately assess component position and stability preoperatively. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Development of a combustor liner composed of ceramic matrix composite (CMC)

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

    Nishio, K.; Igashira, K.I.; Take, K.

    The Research Institute of Advanced Materials Gas-Generator (AMG), which is a joint effort by the Japan Key Technology Center and 14 firms in Japan, has, since fiscal year 1992, been conducting technological studies on an innovative gas generator that will use 20% less fuel, weight 50% less, and emit 70% less NO{sub x} than the conventional gas generator through the use of advanced materials. Within this project, there is an R and D program for applying ceramic matrix composite (CMC) liners to the combustor, which is a major component of the gas generator. In the course of R and D,more » continuous SiC fiber-reinforced SiC composite (SiC{sup F}/SiC) was selected as the most suitable CMD for the combustor liner because of its thermal stability and formability. An evaluation of the applicability of the SiC{sup F}/SiC composite to the combustor liner on the basis of an evaluation of its mechanical properties and stress analysis of a SiC{sup F}/SiC combustor liner was carried out, and trial SiC{sup F}/SiC combustor liners, the largest of which was 500-mm in diameter, were fabricated by the filament winding and PIP (polymer impregnation and pyrolysis) method. Using a SiC{sup F}/SiC liner built to the actual dimensions, a noncooling combustion test was carried out and even when the gas temperature was raised to 1873K at outlet of the liner, no damage was observed after the test. Through their studies, the authors have confirmed the applicability of the selected SiC{sup F}/SiC composite as a combustor liner. In this paper, the authors describe the present state of the R and D of a CMC combustor liner.« less

  13. The vulva skin microclimate: influence of panty liners on temperature, humidity and pH.

    PubMed

    Runeman, Bo; Rybo, Göran; Larkö, Olle; Faergemann, Jan

    2003-01-01

    Many women use panty liners between menstrual periods. The aim of this study was to investigate whether the use of such products might influence the vulva skin. Twelve healthy women were studied on four occasions with three different product constructions and on one occasion without products. Temperature, surface wetness and surface pH were measured on vulva skin. Mean skin temperature when the women were wearing a conventional panty liner (with a non-breathable back sheet) was 35.9 degrees C, compared to 34.4 degrees C when wearing no panty liner at all (p < 0.01) and 34.5 degrees C when using a panty liner with a breathable (i.e. vapour permeable) back sheet (p < 0.01). Skin humidity was significantly higher when the conventional panty liner was used compared to no panty liner or to the breathable panty liner (both cases p < 0.01). The mean pH value at the exterior aspect of the labium majus was 5.8 with the conventional panty liner, 5.2 with no panty liner and 5.3 with the breathable panty liner (p < 0.001 and p < 0.01, respectively). The results indicate that the conventional panty liner changes the vulva skin microclimate, but that the breathable panty liner to a substantial degree keeps the microclimate at an undisturbed level. The actual effect of these differences on microbiological flora will be addressed in a subsequent study.

  14. Comparison of primary zone combustor liner wall temperatures with calculated predictions

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.

    1973-01-01

    Calculated liner temperatures based on a steady-state radiative and convective heat balance at the liner wall were compared with experimental values. Calculated liner temperatures were approximately 8 percent higher than experimental values. A radiometer was used to experimentally determine values of flame temperature and flame emissivity. Film cooling effectiveness was calculated from an empirical turbulent mixing expression assuming a turbulent mixing level of 2 percent. Liner wall temperatures were measured in a rectangular combustor segment 6 by 12 in. and tested at pressures up to 26.7 atm and inlet temperatures up to 922 K.

  15. Axial magnetic field injection in magnetized liner inertial fusion

    NASA Astrophysics Data System (ADS)

    Gourdain, P.-A.; Adams, M. B.; Davies, J. R.; Seyler, C. E.

    2017-10-01

    MagLIF is a fusion concept using a Z-pinch implosion to reach thermonuclear fusion. In current experiments, the implosion is driven by the Z-machine using 19 MA of electrical current with a rise time of 100 ns. MagLIF requires an initial axial magnetic field of 30 T to reduce heat losses to the liner wall during compression and to confine alpha particles during fusion burn. This field is generated well before the current ramp starts and needs to penetrate the transmission lines of the pulsed-power generator, as well as the liner itself. Consequently, the axial field rise time must exceed hundreds of microseconds. Any coil capable of being submitted to such a field for that length of time is inevitably bulky. The space required to fit the coil near the liner, increases the inductance of the load. In turn, the total current delivered to the load decreases since the voltage is limited by driver design. Yet, the large amount of current provided by the Z-machine can be used to produce the required 30 T field by tilting the return current posts surrounding the liner, eliminating the need for a separate coil. However, the problem now is the field penetration time, across the liner wall. This paper discusses why skin effect arguments do not hold in the presence of resistivity gradients. Numerical simulations show that fields larger than 30 T can diffuse across the liner wall in less than 60 ns, demonstrating that external coils can be replaced by return current posts with optimal helicity.

  16. Small gas turbine combustor experimental study - Compliant metal/ceramic liner and performance evaluation

    NASA Technical Reports Server (NTRS)

    Acosta, W. A.; Norgren, C. T.

    1986-01-01

    Combustor research relating to the development of fuel efficient small gas turbine engines capable of meeting future commercial and military aviation needs is currently underway at NASA Lewis. As part of this combustor research, a basic reverse-flow combustor has been used to investigate advanced liner wall cooling techniques. Liner temperature, performance, and exhaust emissions of the experimental combustor utilizing compliant metal/ceramic liners were determined and compared with three previously reported combustors that featured: (1)splash film-cooled liner walls; (2) transpiration cooled liner walls; and (3) counter-flow film cooled panels.

  17. Small gas turbine combustor experimental study: Compliant metal/ceramic liner and performance evaluation

    NASA Technical Reports Server (NTRS)

    Acosta, W. A.; Norgren, C. T.

    1986-01-01

    Combustor research relating to the development of fuel efficient small gas turbine engines capable of meeting future commercial and military aviation needs is currently underway at NASA Lewis. As part of this combustor research, a basic reverse-flow combustor has been used to investigate advanced liner wall cooling techniques. Liner temperature, performance, and exhaust emissions of the experimental combustor utilizing compliant metal/ceramic liners were determined and compared with three previously reported combustors that featured: (1) splash film-cooled liner walls; (2) transpiration cooled liner walls; and (3) counter-flow film cooled panels.

  18. Progress Report on Rotating Liquid Liner Implosion Experiment, 1 June to 31 December 1975.

    DTIC Science & Technology

    A critical question in the use of imploding liner flux compression for controlled fusion has been the stability of the inner surface of the liner ...To study the problem experimentally, the existing NRL Imploding Liner Facility was modified to allow the implosion of rotating liquid metal liners ...Rotational stabilization of lthe inner surface of a decelerating liquid sodium-potassium liner has been demonstrated, with excellent circularity of the

  19. Optimal Spray Application Rates for Ornamental Nursery Liner Production

    USDA-ARS?s Scientific Manuscript database

    Spray deposition and coverage at different application rates for nursery liners of different sizes were investigated to determine the optimal spray application rates. Experiments were conducted on two and three-year old red maple liners. A traditional hydraulic sprayer with vertical booms was used t...

  20. Overview of Hanford Single Shell Tank (SST) Structural Integrity

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

    Rast, Richard S.; Washenfelder, Dennis J.; Johnson, Jeremy M.

    2013-11-14

    To improve the understanding of the single-shell tanks (SSTs) integrity, Washington River Protection Solutions, LLC (WRPS), the USDOE Hanford Site tank contractor, developed an enhanced Single-Shell Tank Integrity Project (SSTIP) in 2009. An expert panel on SST integrity, consisting of various subject matters experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration, Seventeen of these recommendations were used to develop the basis for the M-45-10-1 Change Package for themore » Hanford Federal Agreement and Compliance Order, which is also known as the Tri-Party Agreement. The structural integrity of the tanks is a key element in completing the cleanup mission at the Hanford Site. There are eight primary recommendations related to the structural integrity of Hanford Single-Shell Tanks. Six recommendations are being implemented through current and planned activities. The structural integrity of the Hanford is being evaluated through analysis, monitoring, inspection, materials testing, and construction document review. Structural evaluation in the form of analysis is performed using modern finite element models generated in ANSYS. The analyses consider in-situ, thermal, operating loads and natural phenomena such as earthquakes. Structural analysis of 108 of 149 Hanford Single-Shell Tanks has concluded that the tanks are structurally sound and meet current industry standards. Analysis of the remaining Hanford Single-Shell Tanks is scheduled for FY2014. Hanford Single-Shell Tanks are monitored through a dome deflection program. The program looks for deflections of the tank dome greater than 1/4 inch. No such deflections have been recorded. The tanks are also subjected to visual inspection. Digital cameras record the interior

  1. Experimental Validation of Numerical Simulations for an Acoustic Liner in Grazing Flow

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.; Pastouchenko, Nikolai N.; Jones, Michael G.; Watson, Willie R.

    2013-01-01

    A coordinated experimental and numerical simulation effort is carried out to improve our understanding of the physics of acoustic liners in a grazing flow as well our computational aeroacoustics (CAA) method prediction capability. A numerical simulation code based on advanced CAA methods is developed. In a parallel effort, experiments are performed using the Grazing Flow Impedance Tube at the NASA Langley Research Center. In the experiment, a liner is installed in the upper wall of a rectangular flow duct with a 2 inch by 2.5 inch cross section. Spatial distribution of sound pressure levels and relative phases are measured on the wall opposite the liner in the presence of a Mach 0.3 grazing flow. The computer code is validated by comparing computed results with experimental measurements. Good agreements are found. The numerical simulation code is then used to investigate the physical properties of the acoustic liner. It is shown that an acoustic liner can produce self-noise in the presence of a grazing flow and that a feedback acoustic resonance mechanism is responsible for the generation of this liner self-noise. In addition, the same mechanism also creates additional liner drag. An estimate, based on numerical simulation data, indicates that for a resonant liner with a 10% open area ratio, the drag increase would be about 4% of the turbulent boundary layer drag over a flat wall.

  2. Micro- and Macro-Fluid Dynamics and Acoustics of Resonant Liners

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.; Watson, Willie (Technical Monitor)

    2002-01-01

    The objectives of this project are to perform direct numerical simulation of the micro-fluid and acoustic fields of a resonant acoustic liner and to investigate the physical processes by which incident sound waves are damped by the acoustic liner. We would like to report that our research work and results have fulfilled both objectives of the grant. The following is a summary of the important accomplishments: (1) Two dimensional direct numerical simulation of the flow and acoustic field around the cavity of resonant liner were successfully carried out; (2) The simulations of (1) were extended to include a laminar grazing flow; (3) The numerical simulations provided strong evidence that there are two principal mechanisms by which a resonant liner damps out an incident acoustic wave; (4) A validation test was performed by comparing the computed dissipation coefficients (not impedance) with impedance tube measurements done at GTRI; and (5) Some resources of this grant were used to support the development of new CAA methods. (Our work on numerical simulation of acoustic liners has benefited by the availability of these improved methods).

  3. Color Stability of Silicone or Acrylic Denture Liners: An in Vitro Investigation

    PubMed Central

    Ergun, Gulfem; Nagas, Isil Cekic

    2007-01-01

    Objectives The aim of this study was to compare the color stability of three acrylic based hard liners (Ufi gel hard, Dura-Liner II, Tokuso Rebase) and two silicone based soft liners (Ufi gel permanent, Molloplast B) by using the colorimeter. Methods Sixty disc-shaped samples, with uniform size of 10 mm diameter and 2 mm in thickness were fabricated for each material. Thirty samples were made as control group in distilled water and the remaining thirty samples were weathered in accelerated aging chamber. Color measurements were made before and after distilled water and aging. Data were statistically analyzed using nonparametric Kruskal-Wallis and Mann-Whitney U tests. Results Data showed that there are significant differences among materials in both after distilled water and aging treatments (P<.001). These results indicated that the most discolored liner material was Dura Liner II after aging (ΔE*=16.30) and the least discolored material was Ufi gel permanent after distilled water (ΔE*=0.41). Conclusions Based on the results of this study, silicone based liner materials are considered to be more color stable than acrylic based liner materials. PMID:19212558

  4. Early time studies of cylindrical liner implosions at 1 MA on COBRA

    NASA Astrophysics Data System (ADS)

    Atoyan, L.; Byvank, T.; Cahill, A. D.; Hoyt, C. L.; de Grouchy, P. W. L.; Potter, W. M.; Kusse, B. R.; Hammer, D. A.

    2014-12-01

    Tests of the magnetized liner inertial fusion (MagLIF) concept will make use of the 27 MA Z machine at Sandia National Laboratories, Albuquerque, to implode a cylindrical metal liner to compress and heat preheated, magnetized plasma contained within it. While most pulsed power machines produce much lower currents than the Z-machine, there are issues that can still be addressed on smaller scale facilities. Recent work on the Cornell Beam Research Accelerator (COBRA) has made use of 10 mm long and 4 mm diameter metal liners having different wall thicknesses to study the initiation of plasma on the liner's surface as well as axial magnetic field compression [P.-A. Gourdain et al., Nucl. Fusion 53, 083006 (2013)]. This report presents experimental results with non-imploding liners, investigating the impact the liner's surface structure has on initiation and ablation. Extreme ultraviolet (XUV) imaging and optical 12 frame camera imaging were used to observe and assess emission non-uniformities as they developed. Axial and side-on interferometry was used to determine the distribution of plasma near the liner surface, including the impact of non-uniformities during the plasma initiation and ablation phases of the experiments.

  5. Formation of Imploding Plasma Liners for HEDP and MIF Applications - Diagnostics

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

    Gilmore, Mark; Hsu, Scott; Witherspoon, F. Douglas

    The goal of the plasma liner experiment (PLX) was to explore and demonstrate the feasibility of forming imploding spherical plasma liners that can reach High Energy Density (HED)-relevant (~ 0.1 Mbar) pressures upon stagnation. The plasma liners were to be formed by a spherical array of 30 – 36 railgun-driven hypervelocity plasma jets (Mach 10 – 50). Due to funding and project scope reductions in year two of the project, this initial goal was revised to focus on studies of individual jet propagation, and on two jet merging physics. PLX was a collaboration between a number of partners including Losmore » Alamos National Laboratory, HyperV Technologies, University of New Mexico (UNM), University of Alabama, Huntsville, and University of Nevada, Reno. UNM’s part in the collaboration was primary responsibility for plasma diagnostics. Though full plasma liner experiments could not be performed, the results of single and two jet experiments nevertheless laid important groundwork for future plasma liner investigations. Though challenges were encountered, the results obtained with one and two jets were overwhelmingly positive from a liner formation point of view, and were largely in agreement with predictions of hydrodynamic models.« less

  6. Acoustic Liner Drag: A Parametric Study of Conventional Configurations

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Jones, Michael G.

    2015-01-01

    Interest in the characterization of the aerodynamic drag performance of acoustic liners has increased in the past several years. This paper details experiments in NASA Langley's Grazing Flow Impedance Tube to quantify the relative drag of several conventional perforate-over-honeycomb liner configurations. For a fixed porosity, facesheet hole diameter and cavity depth are varied to study the effect of each. These configurations are selected to span the range of conventional liner geometries used in commercial aircraft engines. Detailed static pressure and acoustic measurements are made for grazing flows up to M=0.5 at 140 dB SPL for tones between 400 and 2800 Hz. These measurements are used to calculate a resistance factor (?) for each configuration. Analysis shows a correlation between perforate hole size and the resistance factor but cavity depth seems to have little influence. Acoustic effects on liner drag are observed to be limited to the lower Mach numbers included in this investigation.

  7. Conductivity and transit time estimates of a soil liner

    USGS Publications Warehouse

    Krapac, I.G.; Cartwright, K.; Panno, S.V.; Hensel, B.R.; Rehfeldt, K.H.; Herzog, B.L.

    1990-01-01

    A field-scale soil linear was built to assess the feasibilty of constructing a liner to meet the saturated hydraulic conductivity requirement of the U.S. EPA (i.e., less than 1 ?? 10-7 cm/s), and to determine the breakthrough and transit times of water and tracers through the liner. The liner, 8 ?? 15 ?? 0.9 m, was constructed in 15-cm compacted lifts using a 20,037-kg pad-foot compactor and standard engineering practices. Estimated saturated hydraulic conductivities were 2.4 ?? 10-9 cm/s, based on data from large-ring infiltrometers; 4.0 ?? 10-8 cm/s from small-ring infiltrometers; and 5.0 ?? 10-8 cm/s from a water-balance analysis. These estimates were derived from 1 year of monitoring water infiltration into the linear. Breakthrough of tracers at the base of the liner was estimated to be between 2 and 13 years, depending on the method of calculation and the assumptions used in the calculation.

  8. Auto-magnetizing liners for magnetized inertial fusion

    DOE PAGES

    Slutz, S. A.; Jennings, C. A.; Awe, T. J.; ...

    2017-01-20

    Here, the MagLIF (Magnetized Liner Inertial Fusion) concept has demonstrated fusion-relevant plasma conditions on the Z accelerator using external field coils to magnetize the fuel before compression. We present a novel concept (AutoMag), which uses a composite liner with helical conduction paths separated by insulating material to provide fuel magnetization from the early part of the drive current, which by design rises slowly enough to avoid electrical breakdown of the insulators. Once the magnetization field is established, the drive current rises more quickly, which causes the insulators to break down allowing the drive current to follow an axial path andmore » implode the liner in the conventional z-pinch manner. There are two important advantages to AutoMag over external field coils for the operation of MagLIF. Low inductance magnetically insulated power feeds can be used to increase the drive current, and AutoMag does not interfere with diagnostic access. Also, AutoMag enables a pathway to energy applications for MagLIF, since expensive field coils will not be damaged each shot. Finally, it should be possible to generate Field Reversed Configurations (FRC) by using both external field coils and AutoMag in opposite polarities. This would provide a means to studying FRC liner implosions on the 100 ns time scale.« less

  9. Combustor liner construction

    NASA Technical Reports Server (NTRS)

    Craig, H. M.; Wagner, W. B.; Strock, W. J. (Inventor)

    1983-01-01

    A combustor liner is fabricated from a plurality of individual segments each containing counter/parallel Finwall material and are arranged circumferentially and axially to define the combustion zone. Each segment is supported by a hook and ring construction to an opened lattice frame with sufficient tolerance between the hook and ring to permit thermal expansion with a minimum of induced stresses.

  10. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Casing and Cementing Requirements § 250.425 What are the requirements for pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure...

  11. Review of Current State of the Art and Key Design Issues With Potential Solutions for Liquid Hydrogen Cryogenic Storage Tank Structures for Aircraft Applications

    NASA Technical Reports Server (NTRS)

    Mital, Subodh K.; Gyekenyesi, John Z.; Arnold, Steven M.; Sullivan, Roy M.; Manderscheid, Jane M.; Murthy, Pappu L. N.

    2006-01-01

    Due to its high specific energy content, liquid hydrogen (LH2) is emerging as an alternative fuel for future aircraft. As a result, there is a need for hydrogen tank storage systems, for these aircraft applications, that are expected to provide sufficient capacity for flight durations ranging from a few minutes to several days. It is understood that the development of a large, lightweight, reusable cryogenic liquid storage tank is crucial to meet the goals of and supply power to hydrogen-fueled aircraft, especially for long flight durations. This report provides an annotated review (including the results of an extensive literature review) of the current state of the art of cryogenic tank materials, structural designs, and insulation systems along with the identification of key challenges with the intent of developing a lightweight and long-term storage system for LH2. The broad classes of insulation systems reviewed include foams (including advanced aerogels) and multilayer insulation (MLI) systems with vacuum. The MLI systems show promise for long-term applications. Structural configurations evaluated include single- and double-wall constructions, including sandwich construction. Potential wall material candidates are monolithic metals as well as polymer matrix composites and discontinuously reinforced metal matrix composites. For short-duration flight applications, simple tank designs may suffice. Alternatively, for longer duration flight applications, a double-wall construction with a vacuum-based insulation system appears to be the most optimum design. The current trends in liner material development are reviewed in the case that a liner is required to minimize or eliminate the loss of hydrogen fuel through permeation.

  12. The Fusion Gain Analysis of the Inductively Driven Liner Compression Based Fusion

    NASA Astrophysics Data System (ADS)

    Shimazu, Akihisa; Slough, John

    2016-10-01

    An analytical analysis of the fusion gain expected in the inductively driven liner compression (IDLC) based fusion is conducted to identify the fusion gain scaling at various operating conditions. The fusion based on the IDLC is a magneto-inertial fusion concept, where a Field-Reversed Configuration (FRC) plasmoid is compressed via the inductively-driven metal liner to drive the FRC to fusion conditions. In the past, an approximate scaling law for the expected fusion gain for the IDLC based fusion was obtained under the key assumptions of (1) D-T fuel at 5-40 keV, (2) adiabatic scaling laws for the FRC dynamics, (3) FRC energy dominated by the pressure balance with the edge magnetic field at the peak compression, and (4) the liner dwell time being liner final diameter divided by the peak liner velocity. In this study, various assumptions made in the previous derivation is relaxed to study the change in the fusion gain scaling from the previous result of G ml1 / 2 El11 / 8 , where ml is the liner mass and El is the peak liner kinetic energy. The implication from the modified fusion gain scaling on the performance of the IDLC fusion reactor system is also explored.

  13. Analysis of Dual Mobility Liner Rim Damage Using Retrieved Components and Cadaver Models.

    PubMed

    Nebergall, Audrey K; Freiberg, Andrew A; Greene, Meridith E; Malchau, Henrik; Muratoglu, Orhun; Rowell, Shannon; Zumbrunn, Thomas; Varadarajan, Kartik M

    2016-07-01

    The objective of this study was to assess the retentive rim of retrieved dual mobility liners for visible evidence of deformation from femoral neck contact and to use cadaver models to determine if anterior soft tissue impingement could contribute to such deformation. Fifteen surgically retrieved polyethylene liners were assessed for evidence of rim deformation. The average time in vivo was 31.4 months, and all patients were revised for reasons other than intraprosthetic dislocation. Liner interaction with the iliopsoas was studied visually and with fluoroscopy in cadaver specimens using a dual mobility system different than the retrieval study. For fluoroscopic visualization, a metal wire was sutured to the iliopsoas and wires were also embedded into grooves on the outer surface of the liner and the inner head. All retrievals showed evidence of femoral neck contact. The cadaver experiments showed that liner motion was impeded by impingement with the iliopsoas tendon in low flexion angles. When observing the hip during maximum hyperextension, 0°, 15°, and 30° of flexion, there was noticeable tenting of the iliopsoas caused by impingement with the liner. Liner rim deformation resulting from contact with the femoral neck likely begins during early in vivo function. The presence of deformation is indicative of a mechanism inhibiting mobility of the liner. The cadaver studies showed that liner motion could be impeded because of its impingement with the iliopsoas. Such soft tissue impingement may be one mechanism by which liner motion is routinely inhibited, which can result in load transfer from the neck to the rim. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Casing and Cementing Requirements § 250.425 What are the requirements for pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal...

  15. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Casing and Cementing Requirements § 250.425 What are the requirements for pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal...

  16. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Casing and Cementing Requirements § 250.425 What are the requirements for pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal...

  17. Modeling of Passive Acoustic Liners from High Fidelity Numerical Simulations

    NASA Astrophysics Data System (ADS)

    Ferrari, Marcello do Areal Souto

    Noise reduction in aviation has been an important focus of study in the last few decades. One common solution is setting up acoustic liners in the internal walls of the engines. However, measurements in the laboratory with liners are expensive and time consuming. The present work proposes a nonlinear physics-based time domain model to predict the acoustic behavior of a given liner in a defined flow condition. The parameters of the model are defined by analysis of accurate numerical solutions of the flow obtained from a high-fidelity numerical code. The length of the cavity is taken into account by using an analytical procedure to account for internal reflections in the interior of the cavity. Vortices and jets originated from internal flow separations are confirmed to be important mechanisms of sound absorption, which defines the overall efficiency of the liner. Numerical simulations at different frequency, geometry and sound pressure level are studied in detail to define the model parameters. Comparisons with high-fidelity numerical simulations show that the proposed model is accurate, robust, and can be used to define a boundary condition simulating a liner in a high-fidelity code.

  18. ELECTRICAL RESISTIVITY TECHNIQUE TO ASSESS THE INTEGRITY OF GEOMEMBRANE LINERS

    EPA Science Inventory

    Two-dimensional electrical modeling of a liner system was performed using computer techniques. The modeling effort examined the voltage distributions in cross sections of lined facilities with different leak locations. Results confirmed that leaks in the liner influenced voltage ...

  19. Landing Gear Door Liners for Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Howerton, Brian M. (Inventor); Van De Ven, Thomas (Inventor)

    2014-01-01

    A landing gear door for retractable landing gear of aircraft includes an acoustic liner. The acoustic liner includes one or more internal cavities or chambers having one or more openings that inhibit the generation of sound at the surface and/or absorb sound generated during operation of the aircraft. The landing gear door may include a plurality of internal chambers having different geometries to thereby absorb broadband noise.

  20. Constraining the Accretion Mode in LINER 1.9s

    NASA Astrophysics Data System (ADS)

    Sabra, Bassem; Der Sahaguian, Elias; Badr, Elie

    2016-01-01

    The accretion mode and the dominant power source in low-ionization nuclear emission-line regions (LINERs), a class of active galactic nuclei (AGN), are still elusive. We focus on a sample of 22 LINER 1.9s (Ho et al. 1997), a subclass of LINERs that show broad Halpha lines, a signature of blackhole-powered accretion, to test the hypothesis that the ionizing continuum emitted by a radiatively inefficient accretion flow (RIAF) could lead to the LINER ultraviolet (UV) emission-line ratios. Optical line-ratio diagrams are a weak diagnostic tool in distinguishing between possible power sources (Sabra et al. 2003). We search the Mikulski Archive for Space Telescopes (MAST) for UV spectra of the objects in the above sample and also perform photoionization simulations using CLOUDY (Ferland et al. 2013). Unfortunately, only one object (NGC 1052; Gabel et al. 2000) of the 22 LINER 1.9s has UV spectra that cover many emission lines; the rest of the objects either do not have any UV spectra, the spectral coverage is in-adequate, or the spectra have very low signal-to-noise ratios. Our photoionization simulations set up two identical grids of clouds with a range of densities and ionization parameters. We illuminate one grid with radiation emitted by a thin accretion disk (AD) and we illuminate the other grid with radiation from a RIAF. We overplot the UV emission-line ratio predictions for AD and RIAF illumination, together with the available line ratios for NGC 1052. Initial results show that UV lines could be used as diagnostics for the accretion mode in AGN. More UV spectral coverage of LINER 1.9s is needed in order to more fully utilize the diagnostic powers of UV emission line ratios.

  1. Contoured-gap coaxial guns for imploding plasma liner experiments

    NASA Astrophysics Data System (ADS)

    Witherspoon, F. D.; Case, A.; Brockington, S.; Cassibry, J. T.; Hsu, S. C.

    2014-10-01

    Arrays of supersonic, high momentum flux plasma jets can be used as standoff compression drivers for generating spherically imploding plasma liners for driving magneto-inertial fusion, hence the name plasma-jet-driven MIF (PJMIF). HyperV developed linear plasma jets for the Plasma Liner Experiment (PLX) at LANL where two guns were successfully tested. Further development at HyperV resulted in achieving the PLX goal of 8000 μg at 50 km/s. Prior work on contoured-gap coaxial guns demonstrated an approach to control the blowby instability and achieved substantial performance improvements. For future plasma liner experiments we propose to use contoured-gap coaxial guns with small Minirailgun injectors. We will describe such a gun for a 60-gun plasma liner experiment. Discussion topics will include impurity control, plasma jet symmetry and topology (esp. related to uniformity and compactness), velocity capability, and techniques planned for achieving gun efficiency of >50% using tailored impedance matched pulse forming networks. Mach2 and UAH SPH code simulations will be included. Work supported by US DOE DE-FG02-05ER54810.

  2. Progress In Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Francis Y. C.; Kirkpatrick, Ronald C.; Knapp, Charles E.; Cassibry, Jason; Eskridge, Richard; Lee, Michael; Smith, James; Martin, Adam; Wu, S. T.; Schmidt, George; hide

    2001-01-01

    Magnetized target fusion (MTF) attempts to combine the favorable attributes of magnetic confinement fusion (MCF) for energy confinement with the attributes of inertial confinement fusion (ICF) for efficient compression heating and wall-free containment of the fusing plasma. It uses a material liner to compress and contain a magnetized plasma. For practical applications, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC).

  3. LOCATING AND REPAIRING LEAKS IN LANDFILL/IMPOUNDMENT FLEXIBLE MEMBRANE LINERS

    EPA Science Inventory

    In the United States, the large quantities of solid and hazardous wastes generated each year are commonly disposed of in landfills and surface impoundments. Geomembrane liners (flexible membrane liners, FMLs) are often used to form an impermeable barrier to prevent migration of c...

  4. Acoustic Panel Liner for an Engine Nacelle

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M. (Inventor); Ayle, Earl (Inventor); Jones, Michael G. (Inventor); Ichihashi, Fumitaka (Inventor)

    2016-01-01

    An acoustic panel liner includes a face sheet, back plate, and liner core positioned there-between, which may be used in an engine nacelle. Elongated chambers contain variable amounts of septa at a calibrated depth or depths. The septa may have varying DC flow resistance. The chambers may have a hexagonal or other polygonal cross sections. The septa, such as mesh caps, may be bonded to an inner wall of a corresponding chamber. The insertion depths may be the same or different. If different, the pattern of distribution of the depths may be randomized.

  5. A Finite Element Theory for Predicting the Attenuation of Extended-Reacting Liners

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Jones, M. G.

    2009-01-01

    A non-modal finite element theory for predicting the attenuation of an extended-reacting liner containing a porous facesheet and located in a no-flow duct is presented. The mathematical approach is to solve separate wave equations in the liner and duct airway and to couple these two solutions by invoking kinematic constraints at the facesheet that are consistent with a continuum theory of fluid motion. Given the liner intrinsic properties, a weak Galerkin finite element formulation with cubic polynomial basis functions is used as the basis for generating a discrete system of acoustic equations that are solved to obtain the coupled acoustic field. A state-of-the-art, asymmetric, parallel, sparse equation solver is implemented that allows tens of thousands of grid points to be analyzed. A grid refinement study is presented to show that the predicted attenuation converges. Excellent comparison of the numerically predicted attenuation to that of a mode theory (using a Haynes 25 metal foam liner) is used to validate the computational approach. Simulations are also presented for fifteen porous plate, extended-reacting liners. The construction of some of the porous plate liners suggest that they should behave as resonant liners while the construction of others suggest that they should behave as broadband attenuators. In each case the finite element theory is observed to predict the proper attenuation trend.

  6. Failure mechanisms and closed reduction of a constrained tripolar acetabular liner.

    PubMed

    Robertson, William J; Mattern, Christopher J; Hur, John; Su, Edwin P; Pellicci, Paul M

    2009-02-01

    Unlike traditional bipolar constrained liners, the Osteonics Omnifit constrained acetabular insert is a tripolar device, consisting of an inner bipolar bearing articulating within an outer, true liner. Every reported failure of the Omnifit tripolar implant has been by failure at the shell-bone interface (Type I failure), failure at the shell-liner interface (Type II failure), or failure of the locking mechanism resulting in dislocation of the bipolar-liner interface (Type III failure). In this report we present two cases of failure of the Omnifit tripolar at the bipolar-femoral head interface. To our knowledge, these are the first reported cases of failure at the bipolar-femoral head interface (Type IV failure). In addition, we described the first successful closed reduction of a Type IV failure.

  7. MEASUREMENT OF THE CURRENT AND SYMMETRY OF THE IMPACT LINER ON THE NTLX EXPERIMENTS

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

    J. STOKES; J. PARKER; ET AL

    A series of four liner implosion experiments, denoted the Near Term Liner Experiments (NTLX) was recently conducted on the Shiva Star capacitor bank at the Air Force Research Laboratory (AFRL). Measurement of the driving currents in these experiments is required for post-shot analysis of the liner implosion and experiments conducted in the target cylinder. A Faraday rotation measurement was fielded on Shiva Star to measure the current and compare with the current measured by a Rogowski coil technique. The Faraday rotation technique measured the 16 MA currents in these experiments with better than 1% precision. In addition, six B-dot probesmore » were fielded at equal angles around a circle in the powerflow channel outside the liner to measure the symmetry of the liner impact on the target cylinder. The B-dot probes measure the local I-dot, which has a jump when the liner impacts the target cylinder. A high-pass filter allows one to measure this jump more accurately. From the relative timing of the jump signals, the offset of the liner axis and the circularity of liner are inferred.« less

  8. Measurement of the current and symmetry of the impact liner on the NTLX experiments

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

    Stokes, J. L.; Tabaka, L. J.; Parker, J. V.

    A series of four liner implosion experiments, denoted the Near Tern Liner Experiments (NTLX) was recently conducted on the Shiva Star capacitor bank at the Air Force Research Laboratory (AFRL). Measurement of the driving currents in these experiments is required for postshot analysis of the liner implosion and experiments conducted in the target cylinder. A Faraday rotation measurement was fielded on Shiva Star to measure the current and compare with the current measured by a Rogowski coil technique. The Faraday rotation technique measured the 16 MA currents in these experiments with better than 1% precision. In addition, six B-dot probesmore » were fielded at equal angles around a circle in the powerflow channel outside the liner to measure the symmetry of the liner impact on the target cylinder. The B-dot probes measure the local Idot, which has a jump when the liner impacts the target cylinder. A high-pass filter allows one to measure this jump more accurately. From the relative timing of the jump signals, the offset of the liner axis and the circularity of liner are inferred.« less

  9. Low cost, SPF aluminum cryogenic tank structure for ALS

    NASA Technical Reports Server (NTRS)

    Anton, Claire E.; Rasmussen, Perry; Thompson, Curt; Latham, Richard; Hamilton, C. Howard; Ren, Ben; Gandhi, Chimata; Hardwick, Dallis

    1992-01-01

    Past production work has shown that cryogenic tank structure for the Shuttle Booster Rockets and the Titan system have very high life cycle costs for the fuel tank structure. The tanks are machined stiffener-skin combination that are subsequently formed into the required contour after machining. The material scrap rate for these configurations are usually high, and the loss of a tank panel due to forming or heat treatment problems is very costly. The idea of reducing the amount of scrap material and scrapped structural members has prompted the introduction of built-up structure for cryogenic tanks to be explored on the ALS program. A build-up structure approach that has shown improvements in life cycle cost over the conventional built-up approach is the use of superplastically formed (SPF) stiffened panels (reducing the overall part count and weight for the tank) resistance spot welded (RSW) to outer tank skin material. The stiffeners provide for general stability of the tank, while the skin material provides hoop direction continuity for the loads.

  10. Labial and Vaginal Microbiology: Effects of Extended Panty Liner Use

    PubMed Central

    Enane, N. A.; Baldwin, S.; Berg, R. W.

    1997-01-01

    Objective: The goals of this study were 1) to better define the labial microflora and 2) to evaluate whether extended non-menstrual use of panty liners would increase genital carriage of undesirable bacteria and predispose to infection. Methods: Healthy female volunteers (224) were prospectively randomized into panty liner wear groups A (Always® deodorant) and B (Always® non-deodorant) and into a control group C (no panty liner wear) with instructions for non-menstrual ± menstrual use ≥5 h daily for 6 months. Selected aerobic bacteria were semiquantitatively cultured from the inner labial groove, the posterior fornix of the vagina, and the cervix pre-study and post-study. Used panty liners were quantitatively cultured, and vaginal secretions were examined by gas chromatography for fatty acid ratios as a measure of microbial flora shifts. Results: At the pre-study, labial microflora in this study population contained significantly higher frequencies of Staphylococcus, coliforms, other gram-negative rods, and enterococci, and a decreased frequency of Gardnerella vaginalis relative to the vaginal microflora. After 6 months use of panty liners the frequencies (and densities) of the selected microorganisms in these two sites had not changed compared to controls, and fatty acid analyses of vaginal secretions gave no evidence of shifts in the microbial flora. Conclusions: Frequencies of selected genital microflora were different for the labia compared to the vagina. No increased carriage of medically important species was detected for either site after 6 months of daily (average 7.8 h) panty liner use. PMID:18476146

  11. Flap Side Edge Liners for Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Khorrami, Mehdi R. (Inventor); Choudhari, Meelan M. (Inventor); Howerton, Brian M. (Inventor)

    2014-01-01

    One or more acoustic liners comprising internal chambers or passageways that absorb energy from a noise source on the aircraft are disclosed. The acoustic liners may be positioned at the ends of flaps of an aircraft wing to provide broadband noise absorption and/or dampen the noise producing unsteady flow features, and to reduce the amount of noise generated due to unsteady flow at the inboard and/or outboard end edges of a flap.

  12. Grazing incidence modeling of a metamaterial-inspired dual-resonance acoustic liner

    NASA Astrophysics Data System (ADS)

    Beck, Benjamin S.

    2014-03-01

    To reduce the noise emitted by commercial aircraft turbofan engines, the inlet and aft nacelle ducts are lined with acoustic absorbing structures called acoustic liners. Traditionally, these structures consist of a perforated facesheet bonded on top of a honeycomb core. These traditional perforate over honeycomb core (POHC) liners create an absorption spectra where the maximum absorption occurs at a frequency that is dictated by the depth of the honeycomb core; which acts as a quarter-wave resonator. Recent advances in turbofan engine design have increased the need for thin acoustic liners that are effective at low frequencies. One design that has been developed uses an acoustic metamaterial architecture to improve the low frequency absorption. Specifically, the liner consists of an array of Helmholtz resonators separated by quarter-wave volumes to create a dual-resonance acoustic liner. While previous work investigated the acoustic behavior under normal incidence, this paper outlines the modeling and predicted transmission loss and absorption of a dual-resonance acoustic metamaterial when subjected to grazing incidence sound.

  13. Consideration of liners and covers in performance assessments

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

    Phifer, Mark A.; Seitz, Robert R.; Suttora, Linda C.

    2014-09-18

    On-site disposal cells are in use and being considered at several United States Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These disposal cells are typically regulated by States and/or the U.S. Environmental Protection Agency under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) in addition to having to comply with requirements in DOE Order 435.1, Radioactive Waste Management due to the radioactive waste. The USDOE-Environmental Management Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnelmore » associated with these CERCLA disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to CERCLA risk assessments and DOE Order 435.1 performance assessments in support of a Record of Decision and Disposal Authorization Statement, respectively. One of the issues considered by the working group, which is addressed in this report, was how to appropriately consider the performance of covers and liners/leachate collections systems in the context of a DOE Order 435.1 performance assessment (PA). This same information may be appropriate for consideration within CERCLA risk assessments for these facilities. These OSDCs are generally developed to meet hazardous waste (HW) disposal design standards under the Resource Conservation and Recovery Act (RCRA) as well as the DOE Order 435.1 performance based standards for disposal of radioactive waste. To meet the standards for HW, the facilities typically include engineered covers and liner/leachate collection systems. Thus, when considering such facilities in the context of a DOE Order 435.1 PA, there is a need to address the evolution of performance of covers and liner/leachate collection systems in the context of meeting a performance standard considering

  14. Effect of ultra-thin liner materials on copper nucleation/wetting and copper grain growth

    NASA Astrophysics Data System (ADS)

    Mueller, Justin E.

    One of the key challenges facing future integrated circuit copper (Cu) interconnect manufacturing is to achieve uniform coverage of PVD Cu seed layer at minimum thickness on a liner and barrier. We have therefore characterized the nucleation and wetting of PVD Cu on various liner surfaces by monitoring in-situ the film's electrical conductance during the initial stages of deposition (0 to 25 nm). Our results showed that the Cu wetting is sensitive to the Cu/liner interfacial properties, while the nucleation depends on the liner microstructure. It was found that a ruthenium (Ru) liner has a good Cu wetting characteristic and allows at the onset nearly layer by layer Cu growth. Because of good wetting, Cu growth is not significantly affected by Ru liner grain size. Tantalum (Ta), however, exhibits poor Cu wetting, which results in an initial stage of three dimensional island growth of Cu. In this case, Cu island coalescing occurs sooner, at a smaller Cu film thickness, when the nucleation site density is increased with a smaller grain size Ta liner. To optimize the seed layer's conductance and step coverage, a liner with combined properties of Ta (for adhesion and barrier formation) and Ru (for wetting and grain growth) may be desired. A hybrid magnetron target has been developed for depositing TaRu liner films at various compositions. The microstructure of the compound liners and their effects on the overgrown Cu seed layer over a wide range of TaRu composition is presented. It was found that below 80% Ru concentration, TaRu films are amorphous. An amorphous liner results in poor Cu nucleation as compared with a crystalline Ta or Ru liner. A comparison of the microstructure of thin Cu films deposited on bcc alpha-Ta and tetragonal beta-Ta surfaces has been carried out. Cu resistivity is lower by 10-15%, accompanied by larger Cu grain size, in as-deposited Cu films of various thickness' (30-120 nm) on beta-Ta as compared to those deposited on alpha-Ta. This is due to

  15. Improved Broadband Liner Optimization Applied to the Advanced Noise Control Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.; Ayle, Earl; Ichihashi, Fumitaka

    2014-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more desirable. This paper describes improvements to a previously established broadband acoustic liner optimization process using the Advanced Noise Control Fan rig as a demonstrator. Specifically, in-duct attenuation predictions with a statistical source model are used to obtain optimum impedance spectra over the conditions of interest. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Constant-depth, double-degree of freedom and variable-depth, multi-degree of freedom designs are carried through design, fabrication, and testing to validate the efficacy of the design process. Results illustrate the value of the design process in concurrently evaluating the relative costs/benefits of these liner designs. This study also provides an application for demonstrating the integrated use of duct acoustic propagation/radiation and liner modeling tools in the design and evaluation of novel broadband liner concepts for complex engine configurations.

  16. Ceramic coating effect on liner metal temperatures of film-cooled annular combustor

    NASA Technical Reports Server (NTRS)

    Claus, R. W.; Wear, J. D.; Liebert, C. H.

    1979-01-01

    An experimental and analytical investigation was conducted to determine the effect of a ceramic coating on the average metal temperatures of full annular, film cooled combustion chamber liner. The investigation was conducted at pressures from 0.50 to 0.062. At all test conditions, experimental results indicate that application of a ceramic coating will result in significantly lower wall temperatures. In a simplified heat transfer analysis, agreement between experimental and calculated liner temperatures was achieved. Simulated spalling of a small portion of the ceramic coating resulted in only small increases in liner temperature because of the thermal conduction of heat from the hotter, uncoated liner metal.

  17. Applied algorithm in the liner inspection of solid rocket motors

    NASA Astrophysics Data System (ADS)

    Hoffmann, Luiz Felipe Simões; Bizarria, Francisco Carlos Parquet; Bizarria, José Walter Parquet

    2018-03-01

    In rocket motors, the bonding between the solid propellant and thermal insulation is accomplished by a thin adhesive layer, known as liner. The liner application method involves a complex sequence of tasks, which includes in its final stage, the surface integrity inspection. Nowadays in Brazil, an expert carries out a thorough visual inspection to detect defects on the liner surface that may compromise the propellant interface bonding. Therefore, this paper proposes an algorithm that uses the photometric stereo technique and the K-nearest neighbor (KNN) classifier to assist the expert in the surface inspection. Photometric stereo allows the surface information recovery of the test images, while the KNN method enables image pixels classification into two classes: non-defect and defect. Tests performed on a computer vision based prototype validate the algorithm. The positive results suggest that the algorithm is feasible and when implemented in a real scenario, will be able to help the expert in detecting defective areas on the liner surface.

  18. 49 CFR 172.331 - Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. 172.331 Section 172.331 Transportation Other Regulations... packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. (a) Each person...

  19. 49 CFR 172.331 - Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. 172.331 Section 172.331 Transportation Other Regulations... packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. (a) Each person...

  20. 49 CFR 172.331 - Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. 172.331 Section 172.331 Transportation Other Regulations... packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. (a) Each person...

  1. 49 CFR 172.331 - Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. 172.331 Section 172.331 Transportation Other Regulations... packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. (a) Each person...

  2. 49 CFR 172.331 - Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. 172.331 Section 172.331 Transportation Other Regulations... packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks. (a) Each person...

  3. Effects of tacky mat contamination on bond degradation for Chemlok/liner and NBR/liner bonds

    NASA Technical Reports Server (NTRS)

    Padilla, A. M.

    1989-01-01

    Tacky mats are placed by the rubber lay-up areas for the solid rocket motor segments. These mats dust off the shoes prior to entering the platform where the lay-up work is performed. The possibility exists that a tacky mat could be touched with gloved hands prior to handling the uncured nitride butadiene rubber (NBR). Tests were run to determine if NBR were accidentally touched would there be any degradation of the liner/NBR bond. The tacky mats were judged solely on the basis of bond degradation caused by either direct or indirect contamination. Test results all indicate that there was no notable NBR/Chemlok or liner/NBR bond degradation on samples that came into contact with the tacky mat material. Testing procedures are described. The tacky mat adhesive composition does not contain fluorocarbons or release agents that would affect bonding.

  4. Thermal model development and validation for rapid filling of high pressure hydrogen tanks

    DOE PAGES

    Johnson, Terry A.; Bozinoski, Radoslav; Ye, Jianjun; ...

    2015-06-30

    This paper describes the development of thermal models for the filling of high pressure hydrogen tanks with experimental validation. Two models are presented; the first uses a one-dimensional, transient, network flow analysis code developed at Sandia National Labs, and the second uses the commercially available CFD analysis tool Fluent. These models were developed to help assess the safety of Type IV high pressure hydrogen tanks during the filling process. The primary concern for these tanks is due to the increased susceptibility to fatigue failure of the liner caused by the fill process. Thus, a thorough understanding of temperature changes ofmore » the hydrogen gas and the heat transfer to the tank walls is essential. The effects of initial pressure, filling time, and fill procedure were investigated to quantify the temperature change and verify the accuracy of the models. In this paper we show that the predictions of mass averaged gas temperature for the one and three-dimensional models compare well with the experiment and both can be used to make predictions for final mass delivery. Furthermore, due to buoyancy and other three-dimensional effects, however, the maximum wall temperature cannot be predicted using one-dimensional tools alone which means that a three-dimensional analysis is required for a safety assessment of the system.« less

  5. Study of Plasma Liner Driven Magnetized Target Fusion Via Advanced Simulations

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

    Samulyak, Roman V.; Brookhaven National Lab.; Parks, Paul

    The feasibility of the plasma liner driven Magnetized Target Fusion (MTF) via terascale numerical simulations will be assessed. In the MTF concept, a plasma liner, formed by merging of a number (60 or more) of radial, highly supersonic plasma jets, implodes on the target in the form of two compact plasma toroids, and compresses it to conditions of the fusion ignition. By avoiding major difficulties associated with both the traditional laser driven inertial confinement fusion and solid liner driven MTF, the plasma liner driven MTF potentially provides a low-cost and fast R&D path towards the demonstration of practical fusion energy.more » High fidelity numerical simulations of full nonlinear models associated with the plasma liner MTF using state-of-art numerical algorithms and terascale computing are necessary in order to resolve uncertainties and provide guidance for future experiments. At Stony Brook University, we have developed unique computational capabilities that ideally suite the MTF problem. The FronTier code, developed in collaboration with BNL and LANL under DOE funding including SciDAC for the simulation of 3D multi-material hydro and MHD flows, has beenbenchmarked and used for fundamental and engineering problems in energy science applications. We have performed 3D simulations of converging supersonic plasma jets, their merger and the formation of the plasma liner, and a study of the corresponding oblique shock problem. We have studied the implosion of the plasma liner on the magnetized plasma target by resolving Rayleigh-Taylor instabilities in 2D and 3D and other relevant physics and estimate thermodynamic conditions of the target at the moment of maximum compression and the hydrodynamic efficiency of the method.« less

  6. Optimization of Microphone Locations for Acoustic Liner Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; June, J. C.

    2015-01-01

    Two impedance eduction methods are explored for use with data acquired in the NASA Langley Grazing Flow Impedance Tube. The first is an indirect method based on the convected Helmholtz equation, and the second is a direct method based on the Kumaresan and Tufts algorithm. Synthesized no-flow data, with random jitter to represent measurement error, are used to evaluate a number of possible microphone locations. Statistical approaches are used to evaluate the suitability of each set of microphone locations. Given the computational resources required, small sample statistics are employed for the indirect method. Since the direct method is much less computationally intensive, a Monte Carlo approach is employed to gather its statistics. A comparison of results achieved with full and reduced sets of microphone locations is used to determine which sets of microphone locations are acceptable. For the indirect method, each array that includes microphones in all three regions (upstream and downstream hard wall sections, and liner test section) provides acceptable results, even when as few as eight microphones are employed. The best arrays employ microphones well away from the leading and trailing edges of the liner. The direct method is constrained to use microphones opposite the liner. Although a number of arrays are acceptable, the optimum set employs 14 microphones positioned well away from the leading and trailing edges of the liner. The selected sets of microphone locations are also evaluated with data measured for ceramic tubular and perforate-over-honeycomb liners at three flow conditions (Mach 0.0, 0.3, and 0.5). They compare favorably with results attained using all 53 microphone locations. Although different optimum microphone locations are selected for the two impedance eduction methods, there is significant overlap. Thus, the union of these two microphone arrays is preferred, as it supports usage of both methods. This array contains 3 microphones in the upstream

  7. Porosity of temporary denture soft liners containing antifungal agents

    PubMed Central

    Lima, Jozely Francisca Mello; Maciel, Janaína Gomes; Hotta, Juliana; Vizoto, Ana Carolina Pero; Honório, Heitor Marques; Urban, Vanessa Migliorini; Neppelenbroek, Karin Hermana

    2016-01-01

    ABSTRACT Incorporation of antifungals in temporary denture soft liners has been recommended for denture stomatitis treatment; however, it may affect their properties. Objective: To evaluate the porosity of a tissue conditioner (Softone) and a temporary resilient liner (Trusoft) modified by minimum inhibitory concentrations (MICs) of antifungal agents for Candida albicans biofilm. Material and Methods: The porosity was measured by water absorption, based on exclusion of the plasticizer effect. Initially, it was determined by sorption isotherms that the adequate storage solution for specimens (65×10×3.3 mm) of both materials was 50% anhydrous calcium chloride (S50). Then, the porosity factor (PF) was calculated for the study groups (n=10) formed by specimens without (control) or with drug incorporation at MICs (nystatin: Ny-0.032 g, chlorhexidine diacetate: Chx-0.064 g, or ketoconazole: Ke-0.128 g each per gram of soft liner powder) after storage in distilled water or S50 for 24 h, seven and 14 d. Data were statistically analyzed by 4-way repeated measures ANOVA and Tukey's test (α=.05). Results: Ke resulted in no significant changes in PF for both liners in water over 14 days (p>0.05). Compared with the controls, Softone and Trusoft PFs were increased at 14-day water immersion only after addition of Ny and Chx, and Chx, respectively (p<0.05). Both materials showed no significant changes in PF in up to 14 days of S50 immersion, compared with the controls (p>0.05). In all experimental conditions, Softone and Trusoft PFs were significantly lower when immersed in S50 compared with distilled water (p<0.05). Conclusions: The addition of antifungals at MICs resulted in no harmful effects for the porosity of both temporary soft liners in different periods of water immersion, except for Chx and Ny in Softone and Chx in Trusoft at 14 days. No deleterious effect was observed for the porosity of both soft liners modified by the drugs at MICs over 14 days of S50 immersion

  8. Acoustic properties and durability of liner materials at non-standard atmospheric conditions

    NASA Technical Reports Server (NTRS)

    Ahuja, K. K.; Gaeta, R. J., Jr.; Hsu, J. S.

    1994-01-01

    This report documents the results of an experimental study on how acoustic properties of certain absorbing liner materials are affected by nonstandard atmospheric conditions. This study was motivated by the need to assess risks associated with incorporating acoustic testing capability in wind tunnels with semicryogenic high Reynolds number aerodynamic and/or low pressure capabilities. The study consisted of three phases: 1) measurement of acoustic properties of selected liner materials at subatmospheric pressure conditions, 2) periodic cold soak and high pressure exposure of liner materials for 250 cycles, and 3) determination of the effect of periodic cold soak on the acoustic properties of the liner materials at subatmospheric conditions and the effect on mechanical resiliency. The selected liner materials were Pyrell foam, Fiberglass, and Kevlar. A vacuum facility was used to create the subatmospheric environment in which an impedance tube was placed to measure acoustic properties of the test materials. An automated cryogenic cooling system was used to simulate periodic cold soak and high pressure exposure. It was found that lower ambient pressure reduced the absorption effectiveness of the liner materials to varying degrees. Also no significant change in the acoustic properties occurred after the periodic cold soak. Furthermore, mechanical resiliency tests indicated no noticeable change.

  9. Acoustic Liner Drag: Measurements on Novel Facesheet Perforate Geometries

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Jones, Michael G.

    2016-01-01

    Interest in characterization of the aerodynamic drag of acoustic liners has increased in the past several years. This paper details experiments in the NASA Langley Grazing Flow Impedance Tube to quantify the relative drag of several perforate-over-honeycomb liner configurations at flow speeds of centerline flow Mach number equals 0.3 and 0.5. Various perforate geometries and orientations are investigated to determine their resistance factors using a static pressure drop approach. Comparison of these resistance factors gives a relative measurement of liner drag. For these same flow conditions, acoustic measurements are performed with tonal excitation from 400 to 3000 hertz at source sound pressure levels of 140 and 150 decibels. Educed impedance and attenuation spectra are used to determine the impact of variations in perforate geometry on acoustic performance.

  10. Metal liner-driven quasi-isentropic compression of deuterium

    NASA Astrophysics Data System (ADS)

    Weinwurm, Marcus; Bland, Simon N.; Chittenden, Jeremy P.

    2013-09-01

    Properties of degenerate hydrogen and deuterium (D) at pressures of the order of terapascals are of key interest to Planetary Science and Inertial Confinement Fusion. In order to recreate these conditions in the laboratory, we present a scheme, where a metal liner drives a cylindrically convergent quasi-isentropic compression in a D fill. We first determined an external pressure history for driving a self-similar implosion of a D shell from a fictitious flow simulation [D. S. Clark and M. Tabak, Nucl. Fusion 47, 1147 (2007)]. Then, it is shown that this D implosion can be recreated inside a beryllium liner by shaping the current pulse. For a peak current of 10.8 MA cold and nearly isochoric D is assembled at around 12 500 kg/m3. Finally, our two-dimensional Gorgon simulations show the robustness of the implosion method to the magneto-Rayleigh-Taylor instability when using a sufficiently thick liner.

  11. Laboratory development and field demonstration of self-sealing/self-healing landfill liner.

    PubMed

    Shi, Caijun; Booth, Rob

    2005-01-01

    The self-sealing/self-healing (SS/SH) barrier concept is based on the principle that two or more parent materials placed in vertical or horizontal layers will react at their interfaces to form insoluble reaction products. These products constitute a seamless impermeable seal, which is resistant to the transmission of leachate and contaminants. A SS/SH liner formulation was developed in the laboratory and demonstrated at the Sudokwon landfill site in South Korea. Laboratory testing results indicated that a seal with a hydraulic conductivity less than 10(-9) m/s formed after two to four weeks of curing at room temperature, and the seal healed itself after it was fractured. The use of the soil from the Sudokwon landfill site instead of sand as the matrix of the parent materials in the SS/SH liner retarded the sealing and healing of the seal, but did not show an obvious effect on the overall sealing and healing capacity of the seal at early stages. The construction and installation of the field demonstration SS/SH liner were carried out in the same way as for a soil cement liner. The quality of the liner was ensured by the enforcement of quality analysis/quality control procedures during installation. A single sealed ring infiltration test was performed on the field demonstration liner 36 days after the installation was completed. The measurement of water infiltration rate indicated that the liner healed after it was fractured. However, the long-term sealing and healing capacity needs to be further investigated.

  12. LINER FOR EXTRUSION BILLET CONTAINERS. Interim Technical Documentary Progress Report, June 5, 1962-September 5, 1962

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

    Spachner, S.A.

    1962-10-31

    A container-sleeve-liner assembly was designed which will provide adequate support for ceramic, ceramic coated metal, or metal liners. The design minimizes mechanical property requirements of liner materials, and permits rapid removal of worn or damaged liners. A high-strength stem was designed and fabricated. Technical literature on high-strength materials was reviewed, and high-strength materials producers were contacted to locate sources and assess applicability of existing materials for refractory metal extrusion liner use. (auth)

  13. Diagnostic Techniques to Elucidate the Aerodynamic Performance of Acoustic Liners

    NASA Technical Reports Server (NTRS)

    June, Jason; Bertolucci, Brandon; Ukeiley, Lawrence; Cattafesta, Louis N., III; Sheplak, Mark

    2017-01-01

    In support of Topic A.2.8 of NASA NRA NNH10ZEA001N, the University of Florida (UF) has investigated the use of flow field optical diagnostic and micromachined sensor-based techniques for assessing the wall shear stress on an acoustic liner. Stereoscopic particle image velocimetry (sPIV) was used to study the velocity field over a liner in the Grazing Flow Impedance Duct (GFID). The results indicate that the use of a control volume based method to determine the wall shear stress is prone to significant error. The skin friction over the liner as measured using velocity curve fitting techniques was shown to be locally reduced behind an orifice, relative to the hard wall case in a streamwise plane centered on the orifice. The capacitive wall shear stress sensor exhibited a linear response for a range of shear stresses over a hard wall. PIV over the liner is consistent with lifting of the near wall turbulent structure as it passes over an orifice, followed by a region of low wall shear stress.

  14. Posttest destructive examination of the steel liner in a 1:6-scale reactor containment model

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

    Lambert, L.D.

    A 1:6-scale model of a nuclear reactor containment model was built and tested at Sandia National Laboratories as part of research program sponsored by the Nuclear Regulatory Commission to investigate containment overpressure test was terminated due to leakage from a large tear in the steel liner. A limited destructive examination of the liner and anchorage system was conducted to gain information about the failure mechanism and is described. Sections of liner were removed in areas where liner distress was evident or where large strains were indicated by instrumentation during the test. The condition of the liner, anchorage system, and concretemore » for each of the regions that were investigated are described. The probable cause of the observed posttest condition of the liner is discussed.« less

  15. Design of the ZTH vacuum liner

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

    Prince, P.P.; Dike, R.S.

    1987-01-01

    The current status of the ZTH vacuum liner design is covered by this report. ZTH will be the first experiment to be installed in the CPRF (Confinement Physics Research Facility) at the Los Alamos National Laboratory and is scheduled to be operational at the rated current of 4 MA in 1992. The vacuum vessel has a 2.4 m major radius and a 40 cm minor radius. Operating parameters which drive the vacuum vessel mechanical design include a 300 C bakeout temperature, an armour support system capable of withstanding 25 kV, a high toroidal resistance, 1250 kPa magnetic loading, a 10more » minute cycle time, and high positional accuracy with respect to the conducting shell. The vacuum vessel design features which satisfy the operating parameters are defined. The liner is constructed of Inconel 625 and has a geometry which alternates sections of thin walled bellows with rigid ribs. These composite sections span between pairs of the 16 diagnostic stations to complete the torus. The thin bellows sections maximize the liner toroidal resistance and the ribs provide support and positional accuracy for the armour in relation to the conducting shell. Heat transfer from the vessel is controlled by a blanket wrap of ceramic fiber insulation and the heat flux is dissipated to a water cooling jacket in the conducting shell.« less

  16. Selected Aspects of Cryogenic Tank Fatigue Calculations for Offshore Application

    NASA Astrophysics Data System (ADS)

    Skrzypacz, J.; Jaszak, P.

    2018-02-01

    The paper presents the way of the fatigue life calculation of a cryogenic tank dedicated for the carriers ship application. The independent tank type C was taken into consideration. The calculation took into account a vast range of the load spectrum resulting in the ship accelerations. The stress at the most critical point of the tank was determined by means of the finite element method. The computation methods and codes used in the design of the LNG tank were presented. The number of fatigue cycles was determined by means of S-N curve. The cumulated linear damage theory was used to determine life factor.

  17. Design, engineering and evaluation of refractory liners for slagging gasifiers. Final report

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

    deTineo, B J; Booth, G; Firestone, R F

    1982-08-01

    The contract for this program was awarded at the end of September 1978. Work was started on 1 October 1978, on Tasks A, B, and E. Task A, Conceptual Liner Designs, and Task B, Test System Design and Construction, were completed. Task C, Liner Tests, and Task D, Liner Design Evaluation, were to begin upon completion of Task B. Task E, Liner Model Development, is inactive after an initial data compilation and theoretical model development effort. It was to be activated as soon as data were available from Task D. Task F, Liner Design Handbook, was active along with Taskmore » A since the reports of both tasks were to use the same format. At this time, Tasks C, D, and F are not to be completed since funding of this project was phased out by DOE directive. The refractory text facility, which was constructed, was tested and found to perform satisfactorily. It is described in detail, including a hazard analysis which was performed. (LTN)« less

  18. Hybrid Composite Cryogenic Tank Structure

    NASA Technical Reports Server (NTRS)

    DeLay, Thomas

    2011-01-01

    A hybrid lightweight composite tank has been created using specially designed materials and manufacturing processes. The tank is produced by using a hybrid structure consisting of at least two reinforced composite material systems. The inner composite layer comprises a distinct fiber and resin matrix suitable for cryogenic use that is a braided-sleeve (and/or a filamentwound layer) aramid fiber preform that is placed on a removable mandrel (outfitted with metallic end fittings) and is infused (vacuum-assisted resin transfer molded) with a polyurethane resin matrix with a high ductility at low temperatures. This inner layer is allowed to cure and is encapsulated with a filamentwound outer composite layer of a distinct fiber resin system. Both inner and outer layer are in intimate contact, and can also be cured at the same time. The outer layer is a material that performs well for low temperature pressure vessels, and it can rely on the inner layer to act as a liner to contain the fluids. The outer layer can be a variety of materials, but the best embodiment may be the use of a continuous tow of carbon fiber (T-1000 carbon, or others), or other high-strength fibers combined with a high ductility epoxy resin matrix, or a polyurethane matrix, which performs well at low temperatures. After curing, the mandrel can be removed from the outer layer. While the hybrid structure is not limited to two particular materials, a preferred version of the tank has been demonstrated on an actual test tank article cycled at high pressures with liquid nitrogen and liquid hydrogen, and the best version is an inner layer of PBO (poly-pphenylenebenzobisoxazole) fibers with a polyurethane matrix and an outer layer of T-1000 carbon with a high elongation epoxy matrix suitable for cryogenic temperatures. A polyurethane matrix has also been used for the outer layer. The construction method is ideal because the fiber and resin of the inner layer has a high strain to failure at cryogenic

  19. Measurement of liner slips, milking time, and milk yield.

    PubMed

    O'Callaghan, E J

    1996-03-01

    Liner slip or rapid air leakage past the mouthpiece of the milking machine liner is related to high rates of new cases of mastitis. A real time technique was developed to monitor the air flow into the milking machine cluster during liner slips as well as to monitor milking time and milk yield using a commercial type pipeline milking system. The air flow into the cluster was measured by recording the pressure differences across an orifice plate placed in the air bypass of an air-milk separator using a differential pressure transducer. Milk yield was recorded by counting the number of milk releases from an electronic milk meter. The release solenoids of the milk meter were linked to a computer. The start and end of milking were manually recorded by switching a two-pole switch connected to a digital input card on the computer, which was programmed to record air flow, milk yield, and milking time. Milk yield, milking time, and air flows during liner slips were recorded simultaneously at each milking unit in an 11-unit herringbone parlor. The system was tested with an experiment with a 4 x 4 Latin square design using four treatments (clusters) and four treatment groups (22 cows per group).

  20. Inductively Driven, 3D Liner Compression of a Magnetized Plasma to Megabar Energy Densities

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

    Slough, John

    To take advantage of the smaller scale, higher density regime of fusion an efficient method for achieving the compressional heating required to reach fusion gain conditions must be found. What is proposed is a more flexible metallic liner compression scheme that minimizes the kinetic energy required to reach fusion. It is believed that it is possible to accomplish this at sub-megajoule energies. This however will require operation at very small scale. To have a realistic hope of inexpensive, repetitive operation, it is essential to have the liner kinetic energy under a megajoule which allows for the survivability of the vacuummore » and power systems. At small scale the implosion speed must be reasonably fast to maintain the magnetized plasma (FRC) equilibrium during compression. For limited liner kinetic energy, it becomes clear that the thinnest liner imploded to the smallest radius consistent with the requirements for FRC equilibrium lifetime is desired. The proposed work is directed toward accomplishing this goal. Typically an axial (Z) current is employed for liner compression. There are however several advantages to using a θ-pinch coil. With the θ-pinch the liner currents are inductively driven which greatly simplifies the apparatus and vacuum system, and avoids difficulties with the post implosion vacuum integrity. With fractional flux leakage, the foil liner automatically provides for the seed axial compression field. To achieve it with optimal switching techniques, and at an accelerated pace however will require additional funding. This extra expense is well justified as the compression technique that will be enabled by this funding is unique in the ability to implode individual segments of the liner at different times. This is highly advantageous as the liner can be imploded in a manner that maximizes the energy transfer to the FRC. Production of shaped liner implosions for additional axial compression can thus be readily accomplished with the

  1. Extended use of the GuideLiner in complex coronary interventions.

    PubMed

    Chan, Pak Hei; Alegria-Barrero, Eduardo; Foin, Nicholas; Paulo, Manuel; Lindsay, Alistair C; Viceconte, Nicola; Di Mario, Carlo

    2015-07-01

    Challenging coronary anatomies including chronic total occlusions (CTO), extreme vessel tortuosity, diseased bypass grafts, and anomalous coronary arteries pose difficulties in coronary interventions. The GuideLiner is a monorail catheter originally developed to facilitate delivery of stents to target lesions in tortuous vessels. We conducted a study on the feasibility and safety of utilising this catheter in a wider array of complex coronary interventions. Consecutive patients undergoing coronary or peripheral interventions where a GuideLiner was used were recruited into this study. Patient demographics, lesion and vessel characteristics, procedural details and outcomes were prospectively entered into our database and analysed. From September 2009 to October 2011, 54 consecutive patients underwent coronary intervention in our institution using a GuideLiner; 21 out of 54 coronary applications were motivated by the need to increase support to cross CTOs, predominantly of the RCA. Anomalous or angulated take-off of the treatment vessels (31%), previously deployed proximal stents (15%), heavy proximal calcification (9%) and tortuosity (7%) accounted for the remaining reasons. One patient had successful renal denervation with the aid of a GuideLiner catheter. Procedural success was 98% in our series with no device-related periprocedural complications such as ostial dissection or myocardial necrosis. The use of a GuideLiner facilitates the approach to complex coronary interventions including chronic total occlusion and saphenous vein graft intervention by providing greater back-up support and easier engagement of coronary ostia.

  2. The vulvar skin microenvironment: influence of different panty liners on temperature, pH and microflora.

    PubMed

    Runeman, Bo; Rybo, Göran; Forsgren-Brusk, Ulla; Larkö, Olle; Larsson, Peter; Faergemann, Jan

    2004-01-01

    The aim of this study was to confirm findings that vapour-impermeable panty liners might impair skin climate, and to assess their impact on the skin microflora. Temperature, surface pH and aerobic microflora were measured on vulvar skin of 102 women. The mean skin temperature was 1.1 degrees C higher when using a vapour-impermeable panty liner compared with not using one. Use of panty liners with vapour-permeable back sheets and acidic cores resulted in skin temperature, pH and microflora levels that were very close to those observed in persons not using liners. The temperature, pH and total number of microorganisms were significantly lower for users of vapour-permeable panty liners than for users of vapour-impermeable ones (p <0.05, p<0.001 and p<0.001, respectively). The microorganism densities were usually higher when using the vapour-impermeable panty liner, but mean differences were minor. The use of panty liners seems not to imply a microbial risk for normal, healthy women.

  3. Skin-Inspired Hydrogel-Elastomer Composite with Application in a Moisture Permeable Prosthetic Limb Liner

    NASA Astrophysics Data System (ADS)

    Ruiz, Esteban

    Recent advances in fields such as 3D printing, and biomaterials, have enabled the development of a moisture permeable prosthetic liner. This project demonstrates the feasibility of the invention by addressing the three primary areas of risk including the mechanical strength, the permeability, and the ability to manufacture. The key enabling technology which allows the liner to operate is the skin inspired hydrogel elastomer composite. The skin inspiration is reflected in the molecular arrangement of the double network of polymers which mimics collagen-elastin toughening in the natural epidermis. A custom formulation for a novel tough double network nanocomposite reinforced hydrogel was developed to improve manufacturability of the liner. The liner features this double network nanocomposite reinforced hydrogel as a permeable membrane which is reinforced on either side by perforated silicone layers manufactured by 3d printing assisted casting. Uniaxial compression tests were conducted on the individual hydrogels, as well as a representative sample of off the shelf prosthetic liners for comparison. Permeability testing was also done on the same set of materials and compared to literature values for traditional hydrogels. This work led to the manufacture of three generations of liner prototypes, with the second and third liner prototype being tested with human participants.

  4. One-dimensional MHD simulations of MTF systems with compact toroid targets and spherical liners

    NASA Astrophysics Data System (ADS)

    Khalzov, Ivan; Zindler, Ryan; Barsky, Sandra; Delage, Michael; Laberge, Michel

    2017-10-01

    One-dimensional (1D) MHD code is developed in General Fusion (GF) for coupled plasma-liner simulations in magnetized target fusion (MTF) systems. The main goal of these simulations is to search for optimal parameters of MTF reactor, in which spherical liquid metal liner compresses compact toroid plasma. The code uses Lagrangian description for both liner and plasma. The liner is represented as a set of spherical shells with fixed masses while plasma is discretized as a set of nested tori with circular cross sections and fixed number of particles between them. All physical fields are 1D functions of either spherical (liner) or small toroidal (plasma) radius. Motion of liner and plasma shells is calculated self-consistently based on applied forces and equations of state. Magnetic field is determined by 1D profiles of poloidal and toroidal fluxes - they are advected with shells and diffuse according to local resistivity, this also accounts for flux leakage into the liner. Different plasma transport models are implemented, this allows for comparison with ongoing GF experiments. Fusion power calculation is included into the code. We performed a series of parameter scans in order to establish the underlying dependencies of the MTF system and find the optimal reactor design point.

  5. The Behavior of Shaped Charges with Open-Poled Hemispherical Liners

    DTIC Science & Technology

    1990-11-01

    Racketenpanzcrbuchse .................................. 14 8. The Japanese SAKURA Bomb .................................... 15 9 . ERF-16’s I-MeV Test...84 A- 9 . Liner and Plug Design for Rounds 4134 and 4146 ....................... 85 A-10. Liner and Plug Design for Round 4141...km/see) .......... 50 8. Cumulative Momentum and Energy (Cutoff Velocity = 3.5 km/sec) .......... 50 9 . Measured Tip Mass and Velocity

  6. OVERVIEW OF HANFORD SINGLE SHELL TANK (SST) STRUCTURAL INTEGRITY - 12123

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

    RAST RS; RINKER MW; WASHENFELDER DJ

    2012-01-25

    To improve the understanding of the single-shell tanks (SSTs) integrity, Washington River Protection Solutions, LLC (WRPS), the USDOE Hanford Site tank contractor, developed an enhanced Single-Shell Tank Integrity Project in 2009. An expert panel on SST integrity, consisting of various subject matters experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration. Seventeen of these recommendations were used to develop the basis for the M-45-10-1 Change Package for the Hanfordmore » Federal Agreement and Compliance Order, which is also known as the Tri-Party Agreement. The structural integrity of the tanks is a key element in completing the cleanup mission at the Hanford Site. There are eight primary recommendations related to the structural integrity of Hanford SSTs. Six recommendations are being implemented through current and planned activities. The structural integrity of the Hanford SSTs is being evaluated through analysis, monitoring, inspection, materials testing, and construction document review. Structural evaluation in the form of analysis is performed using modern finite element models generated in ANSYS{reg_sign} The analyses consider in-situ, thermal, operating loads and natural phenomena such as earthquakes. Structural analysis of 108 of 149 Hanford SSTs has concluded that the tanks are structurally sound and meet current industry standards. Analyses of the remaining Hanford SSTs are scheduled for FY2013. Hanford SSTs are monitored through a dome deflection program. The program looks for deflections of the tank dome greater than 1/4 inch. No such deflections have been recorded. The tanks are also subjected to visual inspection. Digital cameras record the interior surface of the concrete tank domes, looking for

  7. Molding Helmet Liners from Nylon Cloth Made from 1050 Denier Type 700 Nylon Yarns

    DTIC Science & Technology

    Helmet liners were satisfactorily molded from 14 ounce, 2 x 2 basket- weave nylon fabric made of 1050 denier, 168 filaments, 3 to 4 Z turns per inch...type 700 nylon yarn. These helmets liners satisfied the autoclave and the ballistics resistant requirements of Military Specification MIL-L-41800, Liner , Soldier’s Steel Helmet, 1 May 1961.

  8. Porosity of temporary denture soft liners containing antifungal agents.

    PubMed

    Lima, Jozely Francisca Mello; Maciel, Janaína Gomes; Hotta, Juliana; Vizoto, Ana Carolina Pero; Honório, Heitor Marques; Urban, Vanessa Migliorini; Neppelenbroek, Karin Hermana

    2016-01-01

    To evaluate the porosity of a tissue conditioner (Softone) and a temporary resilient liner (Trusoft) modified by minimum inhibitory concentrations (MICs) of antifungal agents for Candida albicans biofilm. The porosity was measured by water absorption, based on exclusion of the plasticizer effect. Initially, it was determined by sorption isotherms that the adequate storage solution for specimens (65×10×3.3 mm) of both materials was 50% anhydrous calcium chloride (S50). Then, the porosity factor (PF) was calculated for the study groups (n=10) formed by specimens without (control) or with drug incorporation at MICs (nystatin: Ny-0.032 g, chlorhexidine diacetate: Chx-0.064 g, or ketoconazole: Ke-0.128 g each per gram of soft liner powder) after storage in distilled water or S50 for 24 h, seven and 14 d. Data were statistically analyzed by 4-way repeated measures ANOVA and Tukey's test (α=.05). Ke resulted in no significant changes in PF for both liners in water over 14 days (p>0.05). Compared with the controls, Softone and Trusoft PFs were increased at 14-day water immersion only after addition of Ny and Chx, and Chx, respectively (p<0.05). Both materials showed no significant changes in PF in up to 14 days of S50 immersion, compared with the controls (p>0.05). In all experimental conditions, Softone and Trusoft PFs were significantly lower when immersed in S50 compared with distilled water (p<0.05). The addition of antifungals at MICs resulted in no harmful effects for the porosity of both temporary soft liners in different periods of water immersion, except for Chx and Ny in Softone and Chx in Trusoft at 14 days. No deleterious effect was observed for the porosity of both soft liners modified by the drugs at MICs over 14 days of S50 immersion.

  9. Liners and Low Luminosity AGN in the ROSAT Database

    NASA Technical Reports Server (NTRS)

    Elvis, Martin; West, Donald K. (Technical Monitor)

    2003-01-01

    This program has led to a series of papers being written and published in the Astrophysical Journal. Together these papers try to explain major parts of the LINER and low luminosity AGN puzzle. One paper ('Accretion Disk Instabilities, Cold Dark Matter Models, and Their Role in Quasar Evolution', Hatziminaoglou E., Siemiginowska A., & Elvis M., 2001, ApJ, 547, 90) describes an analytical model for the evolution of the quasar luminosity function. By combining the Press-Schechter formalism for the masses of initial structures with the luminosity distribution for a population of single mass black holes given by an unstable accretion disk an almost complete end-to-end physics-based model of quasar evolution is produced. In this model black holes spend 75% of their time in a low accretion state (at L(Edd)). This low state population of black holes is likely to be observed as the LINER and low luminosity AGNs in the local universe. Another paper ('Broad Emission Line Regions in AGN: the Link with the Accretion Power', Nicastro F., 2000, ApJ Letters, 530, L65) gives a physical basis for why low state black holes appear as LINERS. By linking the Lightman-Eardley instability in an accretion disk to the ori.gin of a wind that contains the broad emission line cloud material this model explains the large widths seen in these lines as being the Keplerian velocity of the disk at the instability radius. For LINERS the key is that below an accretion rate of 10(exp -3)M(sub Edd)the Lightman-Eardley instability falls within the innermost stable orbit of the disk, and so leaves the entire disk stable. No wind occurs, and so no broad emission lines are seen. Most LINERS are likely to be black holes in this low state. Tests of this model are being considered.

  10. Investigation of the effect of a power feed vacuum gap in solid liner experiments at 1 MA

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

    Bott-Suzuki, S. C., E-mail: sbottsuzuki@ucsd.edu, E-mail: sbottsuzuki@p3ucsd.com; Cordaro, S. W.; Caballero Bendixsen, L. S.

    We present an experimental study of plasma initiation of a solid metal liner at the 1 MA level. In contrast to previous work, we introduce a vacuum gap at one of the liner connections to the power feed to investigate how this affects plasma initiation and to infer how this may affect the symmetry of the liner in compression experiments. We observed that the vacuum gap causes non-uniform plasma initiation both azimuthally and axially in liners, diagnosed by gated optical imaging. Using magnetic field probes external to the liner, we also determined that the optical emission is strongly linked to themore » current distribution in the liner. The apparent persistent of azimuthal non-uniformities may have implications for fusion-scale liner experiments.« less

  11. Development and Validation of an Interactive Liner Design and Impedance Modeling Tool

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Jones, Michael G.; Buckley, James L.

    2012-01-01

    The Interactive Liner Impedance Analysis and Design (ILIAD) tool is a LabVIEW-based software package used to design the composite surface impedance of a series of small-diameter quarter-wavelength resonators incorporating variable depth and sharp bends. Such structures are useful for packaging broadband acoustic liners into constrained spaces for turbofan engine noise control applications. ILIAD s graphical user interface allows the acoustic channel geometry to be drawn in the liner volume while the surface impedance and absorption coefficient calculations are updated in real-time. A one-dimensional transmission line model serves as the basis for the impedance calculation and can be applied to many liner configurations. Experimentally, tonal and broadband acoustic data were acquired in the NASA Langley Normal Incidence Tube over the frequency range of 500 to 3000 Hz at 120 and 140 dB SPL. Normalized impedance spectra were measured using the Two-Microphone Method for the various combinations of channel configurations. Comparisons between the computed and measured impedances show excellent agreement for broadband liners comprised of multiple, variable-depth channels. The software can be used to design arrays of resonators that can be packaged into complex geometries heretofore unsuitable for effective acoustic treatment.

  12. Aerogel Use as a Skin Protective Liner In Space Suits and Prosthetic Limbs Project

    NASA Technical Reports Server (NTRS)

    Roberson, Luke Bennett

    2014-01-01

    Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications for use in space suits and orthopedics. Three tests were performed on several types of aerogel to assess the properties of each material, and our initial findings demonstrated that these materrials would be excellent candidates for liner applications for prosthetics and space suits. The project is currently on hold until additional funding is obtained for application testing at the VH Hospitals in Tampa

  13. Rotating Liner Engine: Improving Efficiency of Heavy Duty Diesels by Significant Friction Reduction, and Extending the Life of Heavy Duty Engines.

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

    Dardalis, Dimitrios

    2013-12-31

    This report describes the work on converting a 4 cylinder Cummins ISB engine into a single cylinder Rotating Liner Engine functioning prototype that can be used to measure the friction benefits of rotating the cylinder liner in a high pressure compression ignition engine. A similar baseline engine was also prepared, and preliminary testing was done. Even though the fabrication of the single cylinder prototype was behind schedule due to machine shop delays, the fundamental soundness of the design elements are proven, and the engine has successfully functioned. However, the testing approach of the two engines, as envisioned by the originalmore » proposal, proved impossible due to torsional vibration resonance caused by the single active piston. A new approach for proper testing has been proposed,« less

  14. Energy efficient engine pin fin and ceramic composite segmented liner combustor sector rig test report

    NASA Technical Reports Server (NTRS)

    Dubiel, D. J.; Lohmann, R. P.; Tanrikut, S.; Morris, P. M.

    1986-01-01

    Under the NASA-sponsored Energy Efficient Engine program, Pratt and Whitney has successfully completed a comprehensive test program using a 90-degree sector combustor rig that featured an advanced two-stage combustor with a succession of advanced segmented liners. Building on the successful characteristics of the first generation counter-parallel Finwall cooled segmented liner, design features of an improved performance metallic segmented liner were substantiated through representative high pressure and temperature testing in a combustor atmosphere. This second generation liner was substantially lighter and lower in cost than the predecessor configuration. The final test in this series provided an evaluation of ceramic composite liner segments in a representative combustor environment. It was demonstrated that the unique properties of ceramic composites, low density, high fracture toughness, and thermal fatigue resistance can be advantageously exploited in high temperature components. Overall, this Combustor Section Rig Test program has provided a firm basis for the design of advanced combustor liners.

  15. Fracture Test Methods for Plastically Responding COPV Liners

    NASA Technical Reports Server (NTRS)

    Dawicke, David S.; Lewis, Joseph C.

    2009-01-01

    An experimental procedure for evaluating the validity of using uniaxial tests to provide a conservative bound on the fatigue crack growth rate behavior small cracks in bi-axially loaded Composite Overwrapped Pressure Vessel (COPV) liners is described. The experimental procedure included the use of a laser notch to quickly generate small surface fatigue cracks with the desired size and aspect ratios. An out-of-plane constraint system was designed to allow fully reversed, fully plastic testing of thin sheet uniaxial coupons. Finally, a method was developed to determine to initiate small cracks in the liner of COPVs.

  16. Diagnosing magnetized liner inertial fusion experiments on Z

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

    Hansen, Stephanie B.; Gomez, Matthew R.; Sefkow, Adam B.

    The Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (~10 12 DD neutrons) from multi-keV deuterium plasmasinertially confined by slow (~10 cm/μs), stable, cylindrical implosions. Moreover, effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 10 10. Further analysis of extensive power, imaging, and spectroscopicx-ray measurements provides a detailed picture of ~3 keV temperatures, 0.3 g/cm 3 densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  17. Diagnosing magnetized liner inertial fusion experiments on Z

    DOE PAGES

    Hansen, Stephanie B.; Gomez, Matthew R.; Sefkow, Adam B.; ...

    2015-05-14

    The Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (~10 12 DD neutrons) from multi-keV deuterium plasmasinertially confined by slow (~10 cm/μs), stable, cylindrical implosions. Moreover, effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 10 10. Further analysis of extensive power, imaging, and spectroscopicx-ray measurements provides a detailed picture of ~3 keV temperatures, 0.3 g/cm 3 densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  18. Design and preliminary results of a semitranspiration cooled (Lamilloy) liner for a high-pressure high-temperature combustor

    NASA Technical Reports Server (NTRS)

    Wear, J. D.; Trout, A. M.; Smith, J. M.; Jones, R. E.

    1978-01-01

    A Lamilloy combustor liner was designed, fabricated and tested in a combustor at pressures up to 8 atmospheres. The liner was fabricated of a three layer Lamilloy structure and designed to replace a conventional step louver liner. The liner is to be used in a combustor that provides hot gases to a turbine cooling test facility at pressures up to 40 atmospheres. The Lamilloy liner was tested extensively at lower pressures and demonstrated lower metal temperatures than the conventional liner, while at the same time requiring about 40 percent less cooling air flow. Tests conducted at combustor exit temperatures in excess of 2200 K have not indicated any cooling or durability problems with the Lamilloy linear.

  19. 49 CFR 172.330 - Tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Tank cars and multi-unit tank car tanks. 172.330..., TRAINING REQUIREMENTS, AND SECURITY PLANS Marking § 172.330 Tank cars and multi-unit tank car tanks. (a... material— (1) In a tank car unless the following conditions are met: (i) The tank car must be marked on...

  20. 49 CFR 172.330 - Tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Tank cars and multi-unit tank car tanks. 172.330..., TRAINING REQUIREMENTS, AND SECURITY PLANS Marking § 172.330 Tank cars and multi-unit tank car tanks. (a... material— (1) In a tank car unless the following conditions are met: (i) The tank car must be marked on...

  1. 49 CFR 172.330 - Tank cars and multi-unit tank car tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Tank cars and multi-unit tank car tanks. 172.330..., TRAINING REQUIREMENTS, AND SECURITY PLANS Marking § 172.330 Tank cars and multi-unit tank car tanks. (a... material— (1) In a tank car unless the following conditions are met: (i) The tank car must be marked on...

  2. Friction Stir Welding of GR-Cop 84 for Combustion Chamber Liners

    NASA Technical Reports Server (NTRS)

    Russell, Carolyn K.; Carter, Robert; Ellis, David L.; Goudy, Richard

    2004-01-01

    GRCop-84 is a copper-chromium-niobium alloy developed by the Glenn Research Center for liquid rocket engine combustion chamber liners. GRCop-84 exhibits superior properties over conventional copper-base alloys in a liquid hydrogen-oxygen operating environment. The Next Generation Launch Technology program has funded a program to demonstrate scale-up production capabilities of GR-Cop 84 to levels suitable for main combustion chamber production for the prototype rocket engine. This paper describes a novel method of manufacturing the main combustion chamber liner. The process consists of several steps: extrude the GR-Cop 84 powder into billets, roll the billets into plates, bump form the plates into cylinder halves and friction stir weld the halves into a cylinder. The cylinder is then metal spun formed to near net liner dimensions followed by finish machining to the final configuration. This paper describes the friction stir weld process development including tooling and non-destructive inspection techniques, culminating in the successful production of a liner preform completed through spin forming.

  3. Plasma Liner Research for MTF at NASA Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. F.; Eskridge, R.; Lee, M.; Martin, A.; Smith, J.; Cassibry, J. T.; Wu, S. T.; Kirkpatrick, R. C.; Knapp, C. E.; Turchi, P. J.; hide

    2002-01-01

    The current research effort at NASA Marshall Space Flight Center (MSFC) in MTF is directed towards exploring the critical physics issues of potential embodiments of MTF for propulsion, especially standoff drivers involving plasma liners for MTF. There are several possible approaches for forming plasma liners. One approach consists of using a spherical array of plasma jets to form a spherical plasma shell imploding towards the center of a magnetized plasma, a compact toroid. Current experimental plan and status to explore the physics of forming a 2-D plasma liner (shell) by merging plasma jets are described. A first-generation coaxial plasma guns (Mark-1) to launch the required plasma jets have been built and tested. Plasma jets have been launched reproducibly with a low jitter, and velocities in excess of 50 km/s for the leading edge of the plasma jet. Some further refinements are being explored for the plasma gun, Successful completion of these single-gun tests will be followed by an experimental exploration of the problems of launching a multiple number of these jets simultaneously to form a cylindrical plasma liner.

  4. A review of bias flow liners for acoustic damping in gas turbine combustors

    NASA Astrophysics Data System (ADS)

    Lahiri, C.; Bake, F.

    2017-07-01

    The optimized design of bias flow liner is a key element for the development of low emission combustion systems in modern gas turbines and aero-engines. The research of bias flow liners has a fairly long history concerning both the parameter dependencies as well as the methods to model the acoustic behaviour of bias flow liners under the variety of different bias and grazing flow conditions. In order to establish an overview over the state of the art, this paper provides a comprehensive review about the published research on bias flow liners and modelling approaches with an extensive study of the most relevant parameters determining the acoustic behaviour of these liners. The paper starts with a historical description of available investigations aiming on the characterization of the bias flow absorption principle. This chronological compendium is extended by the recent and ongoing developments in this field. In a next step the fundamental acoustic property of bias flow liner in terms of the wall impedance is introduced and the different derivations and formulations of this impedance yielding the different published model descriptions are explained and compared. Finally, a parametric study reveals the most relevant parameters for the acoustic damping behaviour of bias flow liners and how this is reflected by the various model representations. Although the general trend of the investigated acoustic behaviour is captured by the different models fairly well for a certain range of parameters, in the transition region between the resonance dominated and the purely bias flow related regime all models lack the correct damping prediction. This seems to be connected to the proper implementation of the reactance as a function of bias flow Mach number.

  5. Shop fabricated corrosion-resistant underground storage tanks

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

    Geyer, W.B.; Stellmach, W.A.

    1995-12-31

    Integral corrosion resistance has long been incorporated into shop fabricated steel underground storage tank design. Since 1969, an industry standard has been the sti-P{sub 3}{reg_sign} (P3) tank. However, the past decade has seen the development of several alternative corrosion resistant and secondary containment technologies. Fiberglass-coated steel composite tanks, and jacketed tanks utilizing various materials as a secondary wall, provide corrosion resistance without the cathodic protection monitoring requirements mandated by the EPA for single-wall P3 tanks. On the other hand, the P3 tank is the only tank technology commonly marketed today with an integral ability to verify its corrosion resistance overmore » the life of the tank. Many existing USTs remain to be replaced or upgraded with corrosion resistance (and other requirements) by the end of 1998. Steel tanks built and installed prior to the advent of pre-engineered, factory-supplied protection against corrosion can be retrofitted with cathodic protection or can be internally lined. Specific installation standards developed by the steel tank industry and the petroleum industry must be followed so as to assure the integrity of the various corrosion resistant technologies developed by the Steel Tank Institute. The technologies describes in this paper will ensure compliance with the corrosion protection requirements of new storage tanks.« less

  6. 49 CFR 174.63 - Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car tanks. 174.63 Section 174.63 Transportation Other....63 Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

  7. 49 CFR 174.63 - Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car tanks. 174.63 Section 174.63 Transportation Other....63 Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

  8. 49 CFR 174.63 - Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car tanks. 174.63 Section 174.63 Transportation Other....63 Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

  9. 49 CFR 174.63 - Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car tanks. 174.63 Section 174.63 Transportation Other....63 Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

  10. 49 CFR 174.63 - Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car tanks. 174.63 Section 174.63 Transportation Other....63 Portable tanks, IM portable tanks, IBCs, Large Packagings, cargo tanks, and multi-unit tank car...

  11. Early time studies of cylindrical liner implosions at 1 MA on COBRA

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

    Atoyan, L., E-mail: la296@cornell.edu; Byvank, T., E-mail: la296@cornell.edu; Cahill, A. D., E-mail: la296@cornell.edu

    Tests of the magnetized liner inertial fusion (MagLIF) concept will make use of the 27 MA Z machine at Sandia National Laboratories, Albuquerque, to implode a cylindrical metal liner to compress and heat preheated, magnetized plasma contained within it. While most pulsed power machines produce much lower currents than the Z-machine, there are issues that can still be addressed on smaller scale facilities. Recent work on the Cornell Beam Research Accelerator (COBRA) has made use of 10 mm long and 4 mm diameter metal liners having different wall thicknesses to study the initiation of plasma on the liner’s surface asmore » well as axial magnetic field compression [P.-A. Gourdain et al., Nucl. Fusion 53, 083006 (2013)]. This report presents experimental results with non-imploding liners, investigating the impact the liner’s surface structure has on initiation and ablation. Extreme ultraviolet (XUV) imaging and optical 12 frame camera imaging were used to observe and assess emission non-uniformities as they developed. Axial and side-on interferometry was used to determine the distribution of plasma near the liner surface, including the impact of non-uniformities during the plasma initiation and ablation phases of the experiments.« less

  12. 75 FR 1596 - Grant of Authority for Subzone Status, Reynolds Packaging LLC (Aluminum Foil Liner Stock...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ... Status, Reynolds Packaging LLC (Aluminum Foil Liner Stock), Louisville, Kentucky Pursuant to its...-purpose subzone at the aluminum foil liner stock manufacturing and distribution facilities of Reynolds... manufacturing and distribution of aluminum foil liner stock and aluminum foil at the facilities of Reynolds...

  13. Extent of fungal growth on fiberglass duct liners with and without biocides under challenging environmental conditions.

    PubMed

    Samimi, Behzad S; Ross, Kristen

    2003-03-01

    Eight brands of fiberglass duct liners, including three that contained biocides, were exposed to challenging environmental conditions that would promote fungal growth. Twenty-four rectangular sheet metal ducts in three groups of eight ducts per group were lined with the eight selected liners. Each group of ducts was exposed to one of the three test conditions within an environmental chamber for a period of 15 days. These conditions were a) 75 percent RH, b) 75 percent RH plus water spray, c) 75 percent RH plus dry nutrient, and d) 75 percent RH plus water plus nutrient. Viable spores of Aspergillus niger were aerosolized into each duct as seed. On the 16th day, air and surface samples for fungal spores were collected from inside ducts. The results of air sampling using N6 sampler and visual inspection indicated that two out of three biocide-containing liners, Permacote and Toughgard, inhibited fungal growth but only under condition A. The third biocide-containing liner, Aeroflex Plus, was effective even when it was wet (conditions A and B). All three biocide-containing liners failed to inhibit fungal growth under conditions C and D. Among the five other types of liners that did not contain biocides, ATCO Flex with a smooth Mylar coating was more preferable, exhibiting lower fungal activity during conditions A, B, and C. All liners failed under condition D when nutrient and water were added together. Surface sampling using adhesive tape failed to produce representative results, apparently due to rough/porous surface of duct liners. It was concluded that duct liners with biocide treatment could be less promoting to microbial growth under high humidity as long as their surfaces remain clean and water-free. A liner with an impermeable and smooth surface seems to be less subject to microbial growth under most conditions than biocide-containing liners having porous and/or rough surfaces.

  14. Effect of long-time immersion of soft denture liners in water on viscoelastic properties.

    PubMed

    Iwasaki, Naohiko; Yamaki, Chisato; Takahashi, Hidekazu; Oki, Meiko; Suzuki, Tetsuya

    2017-09-26

    Aim of this study was to investigate the effect of long-time immersion of soft denture liners in 37°C water on viscoelastic properties. Six silicone-based and two acrylic resin-based soft denture liners were selected. Cylindrical specimens were stored in distilled water at 37°C for 6 months. Viscoelastic properties, which were instantaneous and delayed elastic displacements, viscous flow, and residual displacement, were determined using a creep meter, and analyzed with 2-way analysis of variance and Tukey's comparison (α=0.05). Viscoelastic properties and their time-dependent changes were varied among materials examined. The observed viscoelastic properties of three from six silicone-based liners did not significantly change after 6-month immersion, but those of two acrylic resin-based liners significantly changed with the increase of immersion time. However, the sum of initial instantaneous elastic displacement and delayed elastic displacement of two acrylic resin-based liners during 6-month immersion changed less than 10%, which might indicate clinically sufficient elastic performance.

  15. A systematic review of the effect of daily panty liner use on the vulvovaginal environment.

    PubMed

    Pontes, Ana C; Amaral, Rose L G; Giraldo, Paulo C; Beghini, Joziani; Giraldo, Helena P D; Cordeiro, Etienne S

    2014-10-01

    Whether panty liners predispose to vulvovaginitis is unclear. To clarify the effects of the use of panty liners on the female genital tract. Several electronic databases (including PubMed and Embase) were searched to identify studies published in English before May 3, 2012. Case-control studies, randomized controlled trials, and cohort studies comparing young women who did and did not use panty liners in the intermenstrual period were included. The quality of the studies was assessed using the Newcastle-Ottawa Scale or the Jadad Scale. Data from suitable studies were extracted for analysis. Five articles met the inclusion criteria. Four studies-all of which included only healthy women-found no significant clinical implications arising from the use of panty liners. The fifth study was of women with recurrent candidiasis and showed that use of panty liners was associated with new candidiasis episodes. The intermenstrual use of panty liners does not seem to have a negative effect on the vulvovaginal area. Copyright © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  16. The effectiveness of cut-proof glove liners: cut and puncture resistance, dexterity, and sensibility.

    PubMed

    Salkin, J A; Stuchin, S A; Kummer, F J; Reininger, R

    1995-11-01

    Five types of commercial glove liners (within double latex gloves) were compared to single and double latex gloves for cut and puncture resistance and for relative manual dexterity and degree of sensibility. An apparatus was constructed to test glove-pseudofinger constructs in either a cutting or puncture mode. Cutting forces, cutting speed, and type of blade (serrated or scalpel blade) were varied and the time to cut-through measured by an electrical conductivity circuit. Penetration forces were similarly determined with a scalpel blade and a suture needle using a spring scale loading apparatus. Dexterity was measured with an object placement task among a group of orthopedic surgeons. Sensibility was assessed with Semmes-Weinstein monofilaments, two-point discrimination, and vibrametry using standard techniques and rating scales. A subjective evaluation was performed at the end of testing. Time to cut-through for the liners ranged from 2 to 30 seconds for a rapid oscillating scalpel and 4 to 40 seconds for a rapid oscillating serrated knife under minimal loads. When a 1 kg load was added, times to cut-through ranged from 0.4 to 1.0 second. In most cases, the liners were superior to double latex. On average, 100% more force was required to penetrate the liners with a scalpel and 50% more force was required to penetrate the liners with a suture needle compared to double latex. Object placement task times were not significantly liners compared to double latex gloves. Semmes-Weinstein monofilaments, two-point discrimination, and vibrametry showed no difference in sensibility among the various liners and double latex gloves. Subjects felt that the liners were minimally to moderately impairing. An acclimation period may be required for their effective use.

  17. Diagnosing magnetized liner inertial fusion experiments on Z

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

    Hansen, S. B., E-mail: sbhanse@sandia.gov; Gomez, M. R.; Sefkow, A. B.

    Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (∼10{sup 12} DD neutrons) from multi-keV deuterium plasmas inertially confined by slow (∼10 cm/μs), stable, cylindrical implosions. Effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 10{sup 10}. Analysis of extensive power, imaging, and spectroscopic x-ray measurements provides a detailed picture of ∼3 keV temperatures, 0.3 g/cm{sup 3} densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  18. The effect of accelerated ageing on colour stability of visible light-cured (VLC) chairside denture liners.

    PubMed

    Kostoulas, Ioannis; Polyzois, Gregory; Mitsoudis, Anastasios; Kavoura, Victoria; Frangou, Maria

    2012-06-01

    The purpose of this study was to assess the colour stability of seven visible light-cured (VLC) hard and soft denture liners by an in vitro accelerated ageing test and compare them with two autopolymerised hard and soft liners. Ten specimens of each material were fabricated. The initial colour was measured with a tri-stimulus colorimeter. One set of five specimens was placed in distilled water at 37°C in the dark for 15 days, while the remaining were subjected to UV/visible light-accelerated ageing initially for 24 h and then for 144 h. Colour change (ΔΕ) was calculated. Data were statistically analysed by anova, Tukey and t-tests at α = 0.05. All the liners showed clinically acceptable colour change (ΔΕ ≤ 6.8) in distilled water. The colour changes after ageing for Triad DuaLine, Lightdon U, Ufi Gel H and Light Liner Hard were clinically unacceptable (ΔΕ ≥ 6.8), whereas LightLiner Soft, Astron LC Soft, Triad Resiline and Flexacryl Soft presented slighter and clinically acceptable colour change (ΔΕ ≤ 6.8). Accelerated ageing affected significantly the colour stability of all denture liners tested except Astron LC Soft. Soft VLC denture liners were more colour-stable than hard VLC liners. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

  19. Liner for extrusion billet containers. Interim Technical Documentary Progress Report, February 1--April 30, 1963

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

    Spachner, S. A.

    1963-05-01

    A shrink-fit assembly device for buildup of ceramiccoated liner and sleeve assemblies was tested and modified to develop desired temperatures and suitable heat distribution in sleeves, which were heated. Nine different compositions of fiber metal reinforced ceramic compacts were produced for preliminary evaluation of suitability for extrusion liner use. Procedures were developed for welding short, hollow ceramic cylinders of high-strength metal carbides and borides to form a ceramic extrusion liner of suitable length. Dissassembly tooling for rapid separation of shrink-fitted sleeves from a worn liner was designed, fabricated, and tested. Preliminary extrusion testing of an alumina-coated liner was carried out,more » using SAE 4340 steel billets extruded to rod at 12 : 1 and 16 : 1 ratios. No coating wear was noted after extrusion of 3 billets. (auth)« less

  20. Mass ablation and magnetic flux losses through a magnetized plasma-liner wall interface

    NASA Astrophysics Data System (ADS)

    García-Rubio, F.; Sanz, J.

    2017-07-01

    The understanding of energy and magnetic flux losses in a magnetized plasma medium confined by a cold wall is of great interest in the success of magnetized liner inertial fusion (MagLIF). In a MagLIF scheme, the fuel is magnetized and subsonically compressed by a cylindrical liner. Magnetic flux conservation is degraded by the presence of gradient-driven transport processes such as thermoelectric effects (Nernst) and magnetic field diffusion. In previous publications [Velikovich et al., Phys. Plasmas 22, 042702 (2015)], the evolution of a hot magnetized plasma in contact with a cold solid wall (liner) was studied using the classical collisional Braginskii's plasma transport equations in one dimension. The Nernst term degraded the magnetic flux conservation, while both thermal energy and magnetic flux losses were reduced with the electron Hall parameter ωeτe with a power-law asymptotic scaling (ωeτe)-1/2. In the analysis made in the present paper, we consider a similar situation, but with the liner being treated differently. Instead of a cold solid wall acting as a heat sink, we model the liner as a cold dense plasma with low thermal conduction (that could represent the cryogenic fuel layer added on the inner surface of the liner in a high-gain MagLIF configuration). Mass ablation comes into play, which adds notably differences to the previous analysis. The direction of the plasma motion is inverted, but the Nernst term still convects the magnetic field towards the liner. Magnetization suppresses the Nernst velocity and improves the magnetic flux conservation. Thermal energy in the hot plasma is lost in heating the ablated material. When the electron Hall parameter is large, mass ablation scales as (ωeτe)-3/10, while both the energy and magnetic flux losses are reduced with a power-law asymptotic scaling (ωeτe)-7/10.

  1. Cavity Adaptation of Water-Based Restoratives Placed as Liners under a Resin Composite

    PubMed Central

    Gaintantzopoulou, Maria D.; Eliades, George

    2017-01-01

    Purpose. To investigate the cavity adaptation of mineral trioxide (ProRoot MTA/MT), tricalcium silicate (Biodentine/BD), and glass ionomer (Equia Fil/EF) cements used as liners and the interfacial integrity between those liners and a composite resin placed as the main restorative material. Materials and Methods. Standardized class I cavities (n: 8 per group) were prepared in upper premolars. Cavities were lined with a 1 mm thick layer of each of the tested materials and restored with Optibond FL adhesive and Herculite Precis composite resin. Cavity adaptation of the restorations was investigated by computerized X-ray microtomography. The regions of interest (ROI) were set at the cavity-liner (CL) interface and the liner-resin (LR) interface. The percentage void volume fraction (%VVF) in the ROI was calculated. The specimens were then sectioned and the interfaces were evaluated by reflection optical microscopy, to measure the % length (%LD) of the interfacial gaps. Selected samples were further evaluated by scanning electron microscopy. Statistical analysis was performed by two-way ANOVA and Student-Newman-Keuls multiple comparison test (a = 0.05). Results. MT showed significantly higher %VVF and %LD values in CL interfaces than BD and EF (p < 0.05). No significant differences were found among the materials for the same values at the LR interfaces. Conclusions. When used as a composite liner, ProRoot MTA showed inferior cavity adaptation at dentin/liner interface when compared to Biodentine and Equia Fil. PMID:28465685

  2. Experimental Study of Magnetic Field Production and Dielectric Breakdown of Auto-Magnetizing Liners

    NASA Astrophysics Data System (ADS)

    Shipley, Gabriel; Awe, Thomas; Hutchinson, Trevor; Hutsel, Brian; Slutz, Stephen; Lamppa, Derek

    2017-10-01

    AutoMag liners premagnetize the fuel in MagLIF targets and provide enhanced x-ray diagnostic access and increased current delivery without requiring external field coils. AutoMag liners are composite liners made with discrete metallic helical conduction paths separated by insulating material. First, a low dI/dt ``foot'' current pulse (1 MA in 100 ns) premagnetizes the fuel. Next, a higher dI/dt pulse with larger induced electric field initiates breakdown on the composite liner's; surface, switching the current from helical to axial to implode the liner. Experiments on MYKONOS have tested the premagnetization and breakdown phases of AutoMag and demonstrate axial magnetic fields above 90 Tesla for a 550 kA peak current pulse. Electric fields of 17 MV/m have been generated before breakdown. AutoMag may enhance MagLIF performance by increasing the premagnetization strength significantly above 30 T, thus reducing thermal-conduction losses and mitigating anomalous diffusion of magnetic field out of hotter fuel regions, by, for example, the Nernst thermoelectric effect. This project was funded in part by Sandia's Laboratory Directed Research and Development Program (Projects No. 200169 and 195306).

  3. Interface toughness of a zirconia-veneer system and the effect of a liner application.

    PubMed

    Wang, Gaoqi; Zhang, Song; Bian, Cuirong; Kong, Hui

    2014-09-01

    Chipping of veneering porcelain and delamination of a zirconia-veneer interface are 2 common clinical failure modes for zirconia-based restorations and may be partially due to weak interface bonding. The effect of liner on the bond strength of the interface has not been clearly identified. The purpose of the research was to evaluate the interface toughness between the zirconia core and veneering porcelain by means of a fracture mechanics test and to assess the effect of liner on the bond strength of the interface. Thirty bilayered beam-shape specimens were prepared and divided into 2 groups according to liner application. The specimens in each group were subdivided into 3 subgroups in accordance with 3 different veneer thicknesses. A fracture mechanics test was used on each specimen, and the energy release rate, G, and phase angle, ψ, were calculated according to the experimental results. A video microscope was used to monitor the crack propagation, and a scanning electron microscope was used to identify the fracture mode after testing. Two-way ANOVA and the Tukey honestly significant difference test were performed to analyze the experimental data (α=.05) . At each phase angle, the interfaces without a liner had higher mean G values than the interfaces with a liner. Both of the interfaces showed mixed failure mode with thin layers of a veneer or a liner that remained on the zirconia surfaces. Liner application before veneering reduced the interface toughness between zirconia and veneer. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  4. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations...) You must test each drilling liner (and liner-lap) to a pressure at least equal to the anticipated... drilling or other down-hole operations until you obtain a satisfactory pressure test. If the pressure...

  5. The effect of release liner materials on adhesive contaminants, paper recycling and recycled paper properties

    Treesearch

    Richard Venditti; Richard Gilbert; Andy Zhang; Said Abubakr

    2000-01-01

    Release liner waste material is found in post-consumer waste streams and is also a significant component of the preconsumer waste stream generated in the manufacturing of adhesive products. To date, very little has been reported pertaining to the behavior of release liner in paper recycling. In this study, the effect of the release liner material on the behavior of...

  6. Comparison of Two Acoustic Waveguide Methods for Determining Liner Impedance

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Watson, Willie R.; Tracy, Maureen B.; Parrott, Tony L.

    2001-01-01

    Acoustic measurements taken in a flow impedance tube are used to assess the relative accuracy of two waveguide methods for impedance eduction in the presence of grazing flow. The aeroacoustic environment is assumed to contain forward and backward-traveling acoustic waves, consisting of multiple modes, and uniform mean flow. Both methods require a measurement of the complex acoustic pressure profile over the length of the test liner. The Single Mode Method assumes that the sound pressure level and phase decay-rates of a single progressive mode can be extracted from this measured complex acoustic pressure profile. No a priori assumptions are made in the Finite Element. Method regarding the modal or reflection content in the measured acoustic pressure profile. The integrity of each method is initially demonstrated by how well their no-flow impedances match those acquired in a normal incidence impedance tube. These tests were conducted using ceramic tubular and conventional perforate liners. Ceramic tubular liners were included because of their impedance insensitivity to mean flow effects. Conversely, the conventional perforate liner was included because its impedance is known to be sensitive to mean flow velocity effects. Excellent comparisons between impedance values educed with the two waveguide methods in the absence of mean flow and the corresponding values educed with the normal incident impedance tube were observed. The two methods are then compared for mean flow Mach numbers up to 0.5, and are shown to give consistent results for both types of test liners. The quality of the results indicates that the Single Mode Method should be used when the measured acoustic pressure profile is clearly dominated by a single progressive mode, and the Finite Element Method should be used for all other cases.

  7. Damage Control Plan for International Space Station Recharge Tank Assembly Composite Overwrapped Pressure Vessel

    NASA Technical Reports Server (NTRS)

    Cook, Anthony J.

    2011-01-01

    As NASA has retired the Space Shuttle Program, a new method of transporting compressed gaseous nitrogen and oxygen needed to be created for delivery of these crucial life support resources to the International Space Station (ISS). One of the methods selected by NASA includes the use of highly pressurized, unprotected Recharge Tank Assemblies (RTAs) utilizing Composite Overwrapped Pressure Vessels (COPVs). A COPV consists of a thin liner wrapped with a fiber composite and resin or epoxy. It is typically lighter weight than an all metal pressure vessel of similar volume and therefore provides a higher-efficiency means for gas storage. However COPVs are known to be susceptible to damage resulting from handling, tool drop impacts, or impacts from other objects. As a result, a comprehensive Damage Control Plan has been established to mitigate damage to the RTA COPV throughout its life cycle. The DCP is intended to evaluate and mitigate defined threats during manufacturing, shipping and handling, test, assembly level integration, shipment while pressurized, launch vehicle integration and mission operations by defining credible threats and methods for preventing potential damage while still maintaining the primary goal of resupplying ISS gas resources. A comprehensive threat assessment is performed to identify all threats posed to the COPV during the different phases of its lifecycle. The threat assessment is then used as the basis for creating a series of general inspection, surveillance and reporting requirements which apply across all phases of the COPV's life, targeted requirements only applicable to specific work phases and a series of training courses for both ground personnel and crew aboard the ISS. A particularly important area of emphasis deals with creating DCP requirements for a highly pressurized, large and unprotected RTA COPV for use during Inter Vehicular Activities (IVA) operations in the micro gravity environment while supplying pressurized gas to the

  8. Performance evaluation of a newly developed variable rate sprayer for nursery liner applications

    USDA-ARS?s Scientific Manuscript database

    An experimental variable-rate sprayer designed for liner applications was tested by comparing its spray deposit, coverage, and droplet density inside canopies of six nursery liner varieties with constant-rate applications. Spray samplers, including water sensitive papers (WSP) and nylon screens, wer...

  9. Numerical Investigation of the Acoustic Damping of Plane Acoustic Waves by Perforated Liners with Bias Flow

    NASA Astrophysics Data System (ADS)

    Zhao, Dan; Zhong, Zhi Yuan

    Perforated liners are extensively used in aero-engines and gas turbine combustors to suppress combustion instabilities. These liners, typically subjected to a low Mach number bias flow (a cooling flow through perforated holes), are fitted along the bounding walls of a combustor to convert acoustic energy into flow energy by generating vorticity at the rims of the perforated apertures. To investigate the acoustic damping of such liners with bias flow on plane acoustic waves, a time-domain numerical model is developed to compute acoustic wave propagation in a cylindrical duct with a single-layer liner attached. The damping mechanism of the liner is characterized in real-time by using a 'compliance', developed especially for this work. It is a rational function representation of the frequency-domain homogeneous compliance adapted from the Rayleigh conductivity of a single aperture with mean bias flow in the z-domain. The liner 'compliance' model is then incorporated into partial differential equations of the duct system, which are solved by using the method of lines. The numerical results are then evaluated by comparing with the numerical results of Eldredge and Dowling's frequency-domain model. Good agreement is observed. This confirms that the model and the approach developed are suitable for real-time characterizing the acoustic damping of perforated liners.

  10. Experiment to Form and Characterize a Section of a Spherically Imploding Plasma Liner

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

    Hsu, S. C.; Langendorf, S. J.; Yates, K. C.

    Here, we describe an experiment to form and characterize a section of a spherically imploding plasma liner by merging six supersonic plasma jets that are launched by newly designed contoured-gap coaxial plasma guns. This experiment is a prelude to forming a fully spherical imploding plasma liner using many dozens of plasma guns, as a standoff driver for plasma-jet-driven magneto-inertial fusion. The objectives of the six-jet experiments are to assess the evolution and scalings of liner Mach number and uniformity, which are important metrics for spherically imploding plasma liners to compress magnetized target plasmas to fusion conditions. Lastly, this article describesmore » the design of the coaxial plasma guns, experimental characterization of the plasma jets, six-jet experimental setup and diagnostics, initial diagnostic data from three- and six-jet experiments, and the high-level objectives of associated numerical modeling.« less

  11. Experiment to Form and Characterize a Section of a Spherically Imploding Plasma Liner

    DOE PAGES

    Hsu, S. C.; Langendorf, S. J.; Yates, K. C.; ...

    2017-12-18

    Here, we describe an experiment to form and characterize a section of a spherically imploding plasma liner by merging six supersonic plasma jets that are launched by newly designed contoured-gap coaxial plasma guns. This experiment is a prelude to forming a fully spherical imploding plasma liner using many dozens of plasma guns, as a standoff driver for plasma-jet-driven magneto-inertial fusion. The objectives of the six-jet experiments are to assess the evolution and scalings of liner Mach number and uniformity, which are important metrics for spherically imploding plasma liners to compress magnetized target plasmas to fusion conditions. Lastly, this article describesmore » the design of the coaxial plasma guns, experimental characterization of the plasma jets, six-jet experimental setup and diagnostics, initial diagnostic data from three- and six-jet experiments, and the high-level objectives of associated numerical modeling.« less

  12. A Physics Exploratory Experiment on Plasma Liner Formation

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Knapp, Charles E.; Kirkpatrick, Ronald C.; Siemon, Richard E.; Turchi, Peter

    2002-01-01

    Momentum flux for imploding a target plasma in magnetized target fusion (MTF) may be delivered by an array of plasma guns launching plasma jets that would merge to form an imploding plasma shell (liner). In this paper, we examine what would be a worthwhile experiment to do in order to explore the dynamics of merging plasma jets to form a plasma liner as a first step in establishing an experimental database for plasma-jets driven magnetized target fusion (PJETS-MTF). Using past experience in fusion energy research as a model, we envisage a four-phase program to advance the art of PJETS-MTF to fusion breakeven Q is approximately 1). The experiment (PLX (Plasma Liner Physics Exploratory Experiment)) described in this paper serves as Phase I of this four-phase program. The logic underlying the selection of the experimental parameters is presented. The experiment consists of using twelve plasma guns arranged in a circle, launching plasma jets towards the center of a vacuum chamber. The velocity of the plasma jets chosen is 200 km/s, and each jet is to carry a mass of 0.2 mg - 0.4 mg. A candidate plasma accelerator for launching these jets consists of a coaxial plasma gun of the Marshall type.

  13. Image flows and one-liner graphical image representation.

    PubMed

    Makhervaks, Vadim; Barequet, Gill; Bruckstein, Alfred

    2002-10-01

    This paper introduces a novel graphical image representation consisting of a single curve-the one-liner. The first step of the algorithm involves the detection and ranking of image edges. A new edge exploration technique is used to perform both tasks simultaneously. This process is based on image flows. It uses a gradient vector field and a new operator to explore image edges. Estimation of the derivatives of the image is performed by using local Taylor expansions in conjunction with a weighted least-squares method. This process finds all the possible image edges without any pruning, and collects information that allows the edges found to be prioritized. This enables the most important edges to be selected to form a skeleton of the representation sought. The next step connects the selected edges into one continuous curve-the one-liner. It orders the selected edges and determines the curves connecting them. These two problems are solved separately. Since the abstract graph setting of the first problem is NP-complete, we reduce it to a variant of the traveling salesman problem and compute an approximate solution to it. We solve the second problem by using Dijkstra's shortest-path algorithm. The full software implementation for the entire one-liner determination process is available.

  14. A finite element simulation of sound attenuation in a finite duct with a peripherally variable liner

    NASA Technical Reports Server (NTRS)

    Watson, W. R.

    1977-01-01

    Using multimodal analysis, a variational finite element method is presented for analyzing sound attenuation in a three-dimensional finite duct with a peripherally variable liner in the absence of flow. A rectangular element, with cubic shaped functions, is employed. Once a small portion of a peripheral liner is removed, the attenuation rate near the frequency where maximum attenuation occurs drops significantly. The positioning of the liner segments affects the attenuation characteristics of the liner. Effects of the duct termination are important in the low frequency ranges. The main effect of peripheral variation of the liner is a broadening of the attenuation characteristics in the midfrequency range. Because of matrix size limitations of the presently available computer program, the eigenvalue equations should be solved out of core in order to handle realistic sources.

  15. Performance of a Liner-on-Target Injector for Staged Z-Pinch Experiments

    NASA Astrophysics Data System (ADS)

    Conti, F.; Valenzuela, J. C.; Narkis, J.; Krasheninnikov, I.; Beg, F.; Wessel, F. J.; Ruskov, E.; Rahman, H. U.; McGee, E.

    2016-10-01

    We present the design and characterization of a compact liner-on-target injector, used in the Staged Z-pinch experiments conducted on the UNR-NTF Zebra Facility. Previous experiments and analysis indicate that high-Z gas liners produce a uniform and efficient implosion on a low-Z target plasma. The liner gas shell is produced by an annular solenoid valve and a converging-diverging nozzle designed to achieve a collimated, supersonic, Mach-5 flow. The on-axis target is produced by a coaxial plasma gun, where a high voltage pulse is applied to ionize neutral gas and accelerate the plasma by the J-> × B-> force. Measurements of the liner and target dynamics, resolved by interferometry in space and time, fast imaging, and collection of the emitted light, are presented. The results are compared to the predictions from Computational Fluid Dynamics and MHD simulations that model the injector. Optimization of the design parameters, for upcoming Staged Z-pinch experiments, will be discussed. Advanced Research Projects Agency - Energy, DE-AR0000569.

  16. Do Changes in the Production Process Affect the Outcome of Ceramic Liners: A 3-Year Follow-Up Study.

    PubMed

    Schmidt-Braekling, Tom; Renner, Lisa; Mintz, Douglas N; Waldstein, Wenzel; Endo, Yoshimi; Boettner, Friedrich

    2017-04-01

    In 2011, the current liner was withdrawn from the market because of the potential risk for liner fracture secondary to increased pressures used to assemble the metal locking ring. The present study provides a short-term follow-up of patients with this implant. We retrospectively evaluated 63 consecutive hips in 53 patients operated by a single surgeon using a recalled ceramic-on-ceramic bearing. There were 30 women and 23 men with an average age of 50.6 years (range 20.3-63.5 years). The mean follow-up was 36.8 months. Six hips in 6 patients were revised (9.5%) because of a liner-fracture during the follow-up period. All liner fractures were identified on computer tomography imaging. Nine patients had self-reported episodes of squeaking (14.3%). All 6 patients that underwent revision surgery for liner fracture described squeaking before revision. There were no revisions for other causes. Two of the revised patients had a subsequent dislocation (33%). The recalled ceramic liner lots have an increased liner fracture rate. Patients with mechanical symptoms or squeaking should undergo computer tomography to rule out liner facture. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. USER'S GUIDE TO FLEXIBLE MEMBRANE LINER ADVISORY EXPERT SYSTEM: FLEX VERSION 3.0

    EPA Science Inventory

    The guide is a user manual for the Flexible Membrane Liner Advisory Expert System (FLEX). The system assists in determining if a proposed synthetic liner material will be chemically resistant to a proposed or anticipated leachate from a hazardous waste land disposal site. More sp...

  18. Investigation of a Bio-Inspired Liner Concept

    NASA Technical Reports Server (NTRS)

    Koch, L. Danielle

    2017-01-01

    Four samples of natural reeds, Phragmites australis, were tested in the NASA Langley and Glenn Normal Incidence Impedance Tubes in order to experimentally determine the acoustic absorption coefficients as a function of frequency from 400 to 3000 Hz. Six samples that mimicked the geometry of the assemblies of natural reeds were also designed and additively manufactured from ASA thermoplastic and tested. Results indicate that structures can be manufactured of synthetic materials that mimic the geometry and the low frequency acoustic absorption of natural reeds. This accomplishment demonstrates that a new class of structures can now be considered for a wide range of industrial products that need thin, lightweight, broadband acoustic absorption effective at frequencies below 1000 Hz. Aircraft engine acoustic liners and aircraft cabin acoustic liners, in particular, are two aviation applications that might benefit from further development of this concept.

  19. Analytical and experimental studies of an optimum multisegment phased liner noise suppression concept

    NASA Technical Reports Server (NTRS)

    Sawdy, D. T.; Beckemeyer, R. J.; Patterson, J. D.

    1976-01-01

    Results are presented from detailed analytical studies made to define methods for obtaining improved multisegment lining performance by taking advantage of relative placement of each lining segment. Properly phased liner segments reflect and spatially redistribute the incident acoustic energy and thus provide additional attenuation. A mathematical model was developed for rectangular ducts with uniform mean flow. Segmented acoustic fields were represented by duct eigenfunction expansions, and mode-matching was used to ensure continuity of the total field. Parametric studies were performed to identify attenuation mechanisms and define preliminary liner configurations. An optimization procedure was used to determine optimum liner impedance values for a given total lining length, Mach number, and incident modal distribution. Optimal segmented liners are presented and it is shown that, provided the sound source is well-defined and flow environment is known, conventional infinite duct optimum attenuation rates can be improved. To confirm these results, an experimental program was conducted in a laboratory test facility. The measured data are presented in the form of analytical-experimental correlations. Excellent agreement between theory and experiment verifies and substantiates the analytical prediction techniques. The results indicate that phased liners may be of immediate benefit in the development of improved aircraft exhaust duct noise suppressors.

  20. Competition policy on liner shipping : final review

    DOT National Transportation Integrated Search

    2002-04-16

    If there is one topic that elicits strong reactions in the maritime sector, it is the practice of carriers to commonly fix prices and regulate capacity in international liner shipping. Proponents of these practices vigorously defend these as necessar...

  1. Experimental demonstration of the stabilizing effect of dielectric coatings on magnetically accelerated imploding metallic liners

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

    Awe, Thomas James; Peterson, Kyle J.; Yu, Edmund P.

    Enhanced implosion stability has been experimentally demonstrated for magnetically accelerated liners that are coated with 70 μm of dielectric. The dielectric tamps liner-mass redistribution from electrothermal instabilities and also buffers coupling of the drive magnetic field to the magneto-Rayleigh-Taylor instability. A dielectric-coated and axially premagnetized beryllium liner was radiographed at a convergence ratio [CR=R in,0/R in(z,t)] of 20, which is the highest CR ever directly observed for a strengthless magnetically driven liner. Lastly, the inner-wall radius R in(z,t) displayed unprecedented uniformity, varying from 95 to 130 μm over the 4.0 mm axial height captured by the radiograph.

  2. Experimental demonstration of the stabilizing effect of dielectric coatings on magnetically accelerated imploding metallic liners

    DOE PAGES

    Awe, Thomas James; Peterson, Kyle J.; Yu, Edmund P.; ...

    2016-02-10

    Enhanced implosion stability has been experimentally demonstrated for magnetically accelerated liners that are coated with 70 μm of dielectric. The dielectric tamps liner-mass redistribution from electrothermal instabilities and also buffers coupling of the drive magnetic field to the magneto-Rayleigh-Taylor instability. A dielectric-coated and axially premagnetized beryllium liner was radiographed at a convergence ratio [CR=R in,0/R in(z,t)] of 20, which is the highest CR ever directly observed for a strengthless magnetically driven liner. Lastly, the inner-wall radius R in(z,t) displayed unprecedented uniformity, varying from 95 to 130 μm over the 4.0 mm axial height captured by the radiograph.

  3. Acoustic Characteristics of Various Treatment Panel Designs for HSCT Ejector Liner Acoustic Technology Development Program

    NASA Technical Reports Server (NTRS)

    Salikuddin, M.; Kraft, R. E.; Syed, A. a.; Vu, D. D.; Mungur, P.; Langenbrunner, L. E.; Majjigi, R. K.

    2006-01-01

    The objectives of the initial effort (Phase I) of HSR Liner Technology Program, the selection of promising liner concepts, design and fabrication of these concepts for laboratory tests, testing these liners in the laboratory by using impedance tube and flow ducts, and developing empirical impedance/suppression correlation, are successfully completed. Acoustic and aerodynamic criteria for the liner design are established. Based on these criteria several liners are designed. The liner concepts designed and fabricated include Single-Degree-of-Freedom (SDOF), Two-Degree-of-Freedom (2DOF), and Bulk Absorber. Two types of SDOF treatment are fabricated, one with a perforated type face plate and the other with a wiremesh (woven) type faceplate. In addition, special configurations of these concepts are also included in the design. Several treatment panels are designed for parametric study. In these panels the facesheets of different porosity, hole diameter, and sheet thickness are utilized. Several deep panels (i.e., 1 in. deep) are designed and instrumented to measure DC flow resistance and insitu impedance in the presence of grazing flow. Basic components of these panels (i.e., facesheets, bulk materials, etc.) are also procured and tested. The results include DC flow resistance, normal impedance, and insertion loss.

  4. Numerical study on the lubrication performance of compression ring-cylinder liner system with spherical dimples

    PubMed Central

    Liu, Cheng; Zhang, Yong-Fang; Li, Sha; Müller, Norbert

    2017-01-01

    The effects of surface texture on the lubrication performance of a compression ring-cylinder liner system are studied in this paper. By considering the surface roughness of the compression ring and cylinder liner, a mixed lubrication model is presented to investigate the tribological behaviors of a barrel-shaped compression ring-cylinder liner system with spherical dimples on the liner. In order to determine the rupture and reformulation positions of fluid film accurately, the Jacoboson-Floberg-Olsson (JFO) cavitation boundary condition is applied to the mixed lubrication model for ensuring the mass-conservative law. On this basis, the minimum oil film thickness and average friction forces in the compression ring-cylinder liner system are investigated under the engine-like conditions by changing the dimple area density, radius, and depth. The wear load, average friction forces, and power loss of the compression ring-cylinder liner system with and without dimples are also compared for different compression ring face profiles. The results show that the spherical dimples can produce a larger reduction of friction in mixed lubrication region, and reduce power loss significantly in the middle of the strokes. In addition, higher reduction percentages of average friction forces and wear are obtained for smaller crown height or larger axial width. PMID:28732042

  5. Development of Experimental and Computational Aeroacoustic Tools for Advanced Liner Evaluation

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Watson, Willie R.; Nark, Douglas N.; Parrott, Tony L.; Gerhold, Carl H.; Brown, Martha C.

    2006-01-01

    Acoustic liners in aircraft engine nacelles suppress radiated noise. Therefore, as air travel increases, increasingly sophisticated tools are needed to maximize noise suppression. During the last 30 years, NASA has invested significant effort in development of experimental and computational acoustic liner evaluation tools. The Curved Duct Test Rig is a 152-mm by 381- mm curved duct that supports liner evaluation at Mach numbers up to 0.3 and source SPLs up to 140 dB, in the presence of user-selected modes. The Grazing Flow Impedance Tube is a 51- mm by 63-mm duct currently being fabricated to operate at Mach numbers up to 0.6 with source SPLs up to at least 140 dB, and will replace the existing 51-mm by 51-mm duct. Together, these test rigs allow evaluation of advanced acoustic liners over a range of conditions representative of those observed in aircraft engine nacelles. Data acquired with these test ducts are processed using three aeroacoustic propagation codes. Two are based on finite element solutions to convected Helmholtz and linearized Euler equations. The third is based on a parabolic approximation to the convected Helmholtz equation. The current status of these computational tools and their associated usage with the Langley test rigs is provided.

  6. The Aerodynamic Performance of an Over-the-Rotor Liner With Circumferential Grooves on a High Bypass Ratio Turbofan Rotor

    NASA Technical Reports Server (NTRS)

    Bozak, Richard F.; Hughes, Christopher E.; Buckley, James

    2013-01-01

    While liners have been utilized throughout turbofan ducts to attenuate fan noise, additional attenuation is obtainable by placing an acoustic liner over-the-rotor. Previous experiments have shown significant fan performance losses when acoustic liners are installed over-the-rotor. The fan blades induce an oscillating flow in the acoustic liners which results in a performance loss near the blade tip. An over-the-rotor liner was designed with circumferential grooves between the fan blade tips and the acoustic liner to reduce the oscillating flow in the acoustic liner. An experiment was conducted in the W-8 Single-Stage Axial Compressor Facility at NASA Glenn Research Center on a 1.5 pressure ratio fan to evaluate the impact of this over-the-rotor treatment design on fan aerodynamic performance. The addition of a circumferentially grooved over-the-rotor design between the fan blades and the acoustic liner reduced the performance loss, in terms of fan adiabatic efficiency, to less than 1 percent which is within the repeatability of this experiment.

  7. The Aerodynamic Performance of an Over-The-Rotor Liner with Circumferential Grooves on a High Bypass Ratio Turbofan Rotor

    NASA Technical Reports Server (NTRS)

    Bozak, Rick; Hughes, Christopher; Buckley, James

    2013-01-01

    While liners have been utilized throughout turbofan ducts to attenuate fan noise, additional attenuation is obtainable by placing an acoustic liner over-the-rotor. Previous experiments have shown significant fan performance losses when acoustic liners are installed over-the-rotor. The fan blades induce an oscillating flow in the acoustic liners which results in a performance loss near the blade tip. An over-the-rotor liner was designed with circumferential grooves between the fan blade tips and the acoustic liner to reduce the oscillating flow in the acoustic liner. An experiment was conducted in the W-8 Single-Stage Axial Compressor Facility at NASA Glenn Research Center on a 1.5 pressure ratio fan to evaluate the impact of this over-the-rotor treatment design on fan aerodynamic performance. The addition of a circumferentially grooved over-the-rotor design between the fan blades and the acoustic liner reduced the performance loss, in terms of fan adiabatic efficiency, to less than 1% which is within the repeatability of this experiment.

  8. Evaluation of tensile bond strength of heat cure and autopolymerizing silicone-based resilient denture liners before and after thermocycling.

    PubMed

    Madan, Nishtha; Datta, Kusum

    2012-01-01

    To assess the effect of simulated mouth conditions reproduced with thermocycling on the tensile bond strength of two silicone based resilient denture liners with acrylic resin bases. Two silicone-based soft denture liners (Mollosil - Chairside autopolymerization and Molloplast B - Heat polymerization) were tested. For each liner, 30 specimens with a cross-sectional area of 10 Χ 10 mm and thickness 3 mm were processed between two acrylic blocks (Trevalon). Specimens were divided into a control group that was stored for 24 hours in water at 37°C and a test group that was thermocycled (2500 cycles) between baths of 5° and 55°C. Tensile bond strength (kg/cm²) was determined in a universal testing machine using crosshead speed of 5 mm/min. The student t-test was used to determine the significance of the difference in bond strength between the two liners. The mean tensile bond strength for control and thermocycled specimens of the two liners were: Mollosil (6.82 kg/cm² and 8.41 kg/cm²) and Molloplast-B (16.30 kg/cm² and 13.67 kg/cm²), respectively. Comparison of bond strength of control specimens with thermocycled specimens of the liners indicated a significant difference for both Mollosil (P=0.045) and Molloplast-B (P=0.027). Comparison between control specimens of both liners and thermocycled specimens of both liners indicated a highly significant difference (P<0.001). Heat polymerized resilient denture liner Molloplast-B had higher tensile bond strength than autopolymerizing liner Mollosil regardless of thermocycling. The bond strength of Mollosil increased after thermocycling while that of Molloplast-B decreased after thermocycling. Although heat-polymerized denture liners require more processing time than autopolymerizing liners, but they display much better adhesion properties to denture base resin and should thus be preferred when soft liner has to be used for a longer duration of time.

  9. Fabrication of Low-Density Foam Liners in Hohlraums for NIF Targets

    DOE PAGES

    Bhandarkar, Suhas; Baumann, Ted; Alfonso, Noel; ...

    2018-01-15

    Low-density foam liners are seen as a means to mitigate hohlraum wall motion that can interfere with the inner set of beams that are pointed toward the middle section of the hohlraum. These liners need to meet several requirements, most notably the material choice and the maximum allowable solid fraction and thickness, which necessitate development of new processing capabilities. In this paper, we discuss our strategy and work on fabrication of a tantalum oxide foam liner and its assembly into targets for the National Ignition Facility (NIF). Finally, in particular, we discuss our approach to finding solutions to the uniquemore » challenges that come up in working with such low-density materials so as to be able establish a viable platform for production of cryogenic targets for NIF with foam-lined hohlraums.« less

  10. Fabrication of Low-Density Foam Liners in Hohlraums for NIF Targets

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

    Bhandarkar, Suhas; Baumann, Ted; Alfonso, Noel

    Low-density foam liners are seen as a means to mitigate hohlraum wall motion that can interfere with the inner set of beams that are pointed toward the middle section of the hohlraum. These liners need to meet several requirements, most notably the material choice and the maximum allowable solid fraction and thickness, which necessitate development of new processing capabilities. In this paper, we discuss our strategy and work on fabrication of a tantalum oxide foam liner and its assembly into targets for the National Ignition Facility (NIF). Finally, in particular, we discuss our approach to finding solutions to the uniquemore » challenges that come up in working with such low-density materials so as to be able establish a viable platform for production of cryogenic targets for NIF with foam-lined hohlraums.« less

  11. Development of Lightweight, Compact, Structurally-Integrated Acoustic Liners for Broadband Low-Frequency Noise Mitigation

    NASA Astrophysics Data System (ADS)

    Chambers, Andrew T.

    Airborne noise with a low dominant frequency content (< 500 Hz) has detrimental effects in many applications, but is as yet beyond the scope of conventional acoustic noise mitigation techniques using liners, foams or claddings owing to mass and volume considerations. Its low evanescence contributes significantly to environmental noise pollution, and unwanted structural vibrations causing diminished efficiency, comfort, payload integrity and mission capabilities. An alternative approach using liner configurations with realistic mass and volume constraints having innovative 'folded' core geometries is investigated to ascertain its low-frequency noise absorption characteristics. In contrast to mass-driven approaches, the folded core approach relies on tailoring interactions between acoustic resonances to tune the liner's impedance to suit the dominant low-frequency content of the source. This allows to keep non-structural mass-addition to a minimum, while retaining an overall thickness comparable to conventional liners for these low-frequency liner designs. The relative acoustic performance of various candidate folded core designs is evaluated by means of a new composite metric termed the Low-Frequency Performance (LFP) factor, which is educed from the absorption coefficient spectrum obtained using Zwikker-Kosten Transmission Line (ZKTL) theory-based numerical studies. An LFP-based software tool is developed to determine optimal 3D cavity packing for a prescribed liner volume and target frequency range. ZKTL-based parametric studies on core dimensions and face sheet porosity are utilized for detailed design of test articles. Experimental verification of absorption coefficient spectra conducted using 3D printed test articles in a normal incidence acoustic impedance tube yield good correlation with simulations. More than 100 Hz of continuous bandwidth with an absorption coefficient greater than 0.6 is shown to be possible in the 300 to 400 Hz range with a 38.1-mm (1

  12. Theory of formation of helical structures in a perfectly conducting, premagnetized Z-pinch liner

    NASA Astrophysics Data System (ADS)

    Yu, Edmund; Velikovich, Alexander; Peterson, Kyle

    2014-10-01

    The magnetized liner inertial fusion (MagLIF) concept uses an azimuthal magnetic field to collapse a thick metallic liner containing preheated fusion fuel. A critical component of the concept is an axial magnetic field, permeating both the fuel and surrounding liner, which reduces the compression necessary to achieve fusion conditions. Recent experiments demonstrate that a liner premagnetized with a 10 T axial field develops helical structures with a pitch significantly larger than an estimate of Bz /Bθ would suggest. The cause of the helical perturbations is still not understood. In this work, we present an analytic, linear theory in which we model the liner as a perfectly conducting metal, and study how bumps and divots on its surface redirect current flow, resulting in perturbations to B as well as j × B . We show that in the presence of axial and azimuthal magnetic field, the theory predicts divots will grow and deform at an angle determined by the magnetic field. We compare theoretical results with three dimensional, resistive MHD simulations. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under DE-AC04-94AL85000.

  13. Azimuthal Current Density Distribution Resulting from a Power Feed Vacuum Gap in Metallic Liner Experiments at 1 MA

    NASA Astrophysics Data System (ADS)

    Bott-Suzuki, Simon; Cordaro, S. W.; Caballero Bendixsen, L. S.; Atoyan, L.; Byvank, T.; Potter, W.; Kusse, B. R.; Greenly, J. B.; Hammer, D. A.; Chittenden, J. P.; Jennings, C. A.

    2015-11-01

    We present a study investigating the initiation of plasma in solid, metallic liners where the liner thickness is large compared to the collisionless skin depth. A vacuum gap is introduced in the power feed and we investigate the effect of this on the azimuthal initiation of plasma in the liner. We present optical emission data from aluminum liners on the 1 MA, 100ns COBRA generator. We use radial and axial gated imaging and streak photography, which show a dependence of onset of emission with the size of a small power-feed vacuum gap. The evolution of ``hot-spots'' generated from breakdown vacuum gap evolves relatively slowly and azimuthal uniformity is not observed on the experimental time-scale. We also show measurements of the B-field both outside and inside the liner, using miniature Bdot probes, which show a dependence on the liner diameter and thickness, and a correlation to the details of the breakdown. These data will be compared to magneto-hydrodynamic simulations to infer how such non-uniformities may affect full liner implosion experiments.

  14. Adsorption of oils, heavy metals and dyes by recovered carbon powder from spent pot liner of aluminum smelter plant.

    PubMed

    Mazumder, B; Devi, Sasmita Rani

    2008-07-01

    Aluminum smelter plants employ Hall-Heroult electrolysis cells for electrolysis of molten cryolite to recover aluminum metal by electrolysis. These cells use carbon cathode blocks as a lining material inside. At the end of service life of the cells, pot lines are discarded and new carbon blocks are laid for fresh charging. These used carbon cathode blocks, known as spent pot liners, are heavily infested with toxic elements such as fluoride, cyanide, alkali, etc. Therefore, their disposal in open field poses great environmental risk. A simple process has been developed for decontamination of these spent pot liners and to recover its carbon value. The experiments indicated that this carbon, in the form of fine powder (around 20 micron in size) can absorb toxic elements like heavy metals, dyes, oils, etc. to a great extent and thus can be used for mitigating environmental pollution occuring due to various toxic wastes.

  15. Application of fiber Bragg grating sensors to real-time strain measurement of cryogenic tanks

    NASA Astrophysics Data System (ADS)

    Takeda, Nobuo; Mizutani, Tadahito; Hayashi, Kentaro; Okabe, Yoji

    2003-08-01

    Although many researches of strain measurement using fiber Bragg grating (FBG) sensors were conducted, there were few applications of FBG sensors to spacecraft in operation. It is very significant to develop an onboard system for the real-time strain measurement during the flight operation. In the present research, the real-time strain measurement of a composite liquid hydrogen (LH2) tank, which consisted of CFRP and aluminum liner, was attempted. Adhesive property of the FBG sensors was investigated first of all. As a result, UV coated FBG sensors and polyurethane adhesive were adopted. Then, reflection spectra from FBG sensors were measured through the tensile test at liquid helium (LHe) temperature. Since the center wavelength shifted in proportion to the applied strain, the FBG sensor was suitable as a precise strain sensor even at LHe temperature. Next, the development of an onboard FBG demodulator was discussed. This onboard demodulator was designed for weight saving to be mounted on a reusable rocket vehicle test (RVT) operated by the Institute of Space and Astronautical Science (ISAS). FBG sensors were bonded on the surface of the composite LH2 tank for the RVT. Then, strain measurement using the onboard demodulator was conducted through the cryogenic pressure test of the tank and compared with the result measured using the optical spectrum analyzer (OSA).

  16. On the attenuation of sound by three-dimensionally segmented acoustic liners in a rectangular duct

    NASA Technical Reports Server (NTRS)

    Koch, W.

    1979-01-01

    Axial segmentation of acoustically absorbing liners in rectangular, circular or annual duct configurations is a very useful concept for obtaining higher noise attenuation with respect to the bandwidth of absorption as well as the maximum attenuation. As a consequence, advanced liner concepts are proposed which induce a modal energy transfer in both cross-sectional directions to further reduce the noise radiated from turbofan engines. However, these advanced liner concepts require three-dimensional geometries which are difficult to treat theoretically. A very simple three-dimensional problem is investigated analytically. The results show a strong dependence on the positioning of the liner for some incident source modes while the effect of three-dimensional segmentation appears to be negligible over the frequency range considered.

  17. Excitation Mechanisms of Near-Infrared Emission Lines in LINER Galaxies

    NASA Astrophysics Data System (ADS)

    Boehle, Anna

    2017-01-01

    I will present high spatial resolution, integral field spectroscopic observations of the nearby LINER (low ionization nuclear emission line region) galaxy NGC 404. LINERs are found at the centers of ~1/3 of galaxies within 40 Mpc, but their physical nature is not well understood. Although NGC 404 is thought to host a intermediate mass black hole at its center, it is unclear whether accretion onto the black hole or another mechanism such as shock excitation drives its LINER emission. We use the OSIRIS near-infrared integral field spectrograph at Keck Observatory behind laser guide star adaptive optics to map the strength and kinematics of [FeII], H2, and hydrogen recombination lines in the nucleus of NGC 404. These observations have a spatial pixel sampling of 0.5 pc and span the central 30 pc of the galaxy. We find that the ionized and molecular gas show differences in their morphology and kinematics on parsec scales. In particular, there are regions with line ratios of [FeII]/Pa-β that are much higher than previously seen in spatially integrated spectra, significantly restricting the possible excitation mechanisms of the near-infrared emission lines in this source. We are also applying these analysis techniques to 10 additional nearby LINERs, a part of a larger sample of 14 sources, to understand what drives the emission lines in these active galaxies. As a part of this program, I worked on the upgrade of the detector in the OSIRIS spectrograph, which has allowed observations for this survey obtained since January 2016 to be taken with increased instrument sensitivity of a factor of ~2 at J-band wavelengths (1.2 - 1.4 microns) and ~1.6 at H- and K-band wavelengths (1.5 - 2.4 microns). I will present results from the LINER survey, the OSIRIS detector upgrade, and also touch on related work using stellar orbits around the Milky Way supermassive black hole Sgr A* to constrain the mass and distance to our own Galactic Center.

  18. Graphite-fiber-reinforced polyimide liners of various compositions in plain spherical bearings

    NASA Technical Reports Server (NTRS)

    Sliney, H. E.; Jacobson, T. P.

    1978-01-01

    A plain spherical bearing design with a ball diameter of 28.6 mm, a race length of 12.7 mm, and a 1.7-mm-thick, molded composite liner was evaluated. The liner material is a self-lubricating composite of graphite-fiber-reinforced polyimide resin (GFRPI). The liner is prepared by transfer molding a mixture of one part chopped graphite fiber and one part partially polymerized resin into the space between the bearing ball and the outer race and then completing the polymerization under heat and pressure. Several liner compositions were evaluated: two types of polyimide, condensation and addition; two types of graphite fiber, low and high modulus; and four powder additives - cadmium oxide, cadmium iodide, graphite fluoride, and molybdenum disulfide. The bearings were oscillated + or - 15 deg at 1 Hz for 20 kilocycles under a radial unit load of 29 MN sq m (4200 psi) in dry air at 25, 200, or 315 C. Both types of fiber and polyimide gave low friction and wear. A simple equation was developed to fit the wear-time data and adequately predicted wear to 100 kilocycles.

  19. BrainLiner: A Neuroinformatics Platform for Sharing Time-Aligned Brain-Behavior Data

    PubMed Central

    Takemiya, Makoto; Majima, Kei; Tsukamoto, Mitsuaki; Kamitani, Yukiyasu

    2016-01-01

    Data-driven neuroscience aims to find statistical relationships between brain activity and task behavior from large-scale datasets. To facilitate high-throughput data processing and modeling, we created BrainLiner as a web platform for sharing time-aligned, brain-behavior data. Using an HDF5-based data format, BrainLiner treats brain activity and data related to behavior with the same salience, aligning both behavioral and brain activity data on a common time axis. This facilitates learning the relationship between behavior and brain activity. Using a common data file format also simplifies data processing and analyses. Properties describing data are unambiguously defined using a schema, allowing machine-readable definition of data. The BrainLiner platform allows users to upload and download data, as well as to explore and search for data from the web platform. A WebGL-based data explorer can visualize highly detailed neurophysiological data from within the web browser, and a data-driven search feature allows users to search for similar time windows of data. This increases transparency, and allows for visual inspection of neural coding. BrainLiner thus provides an essential set of tools for data sharing and data-driven modeling. PMID:26858636

  20. Magnetic pressure effects in a plasma-liner interface

    NASA Astrophysics Data System (ADS)

    García-Rubio, F.; Sanz, J.

    2018-04-01

    A theoretical analysis of magnetic pressure effects in a magnetized liner inertial fusion-like plasma is presented. In previous publications [F. García-Rubio and J. Sanz, Phys. Plasmas 24, 072710 (2017)], the evolution of a hot magnetized plasma in contact with a cold unmagnetized plasma, aiming to represent the hot spot and liner, respectively, was investigated in planar geometry. The analysis was made in a double limit low Mach and high thermal to magnetic pressure ratio β. In this paper, the analysis is extended to an arbitrary pressure ratio. Nernst, Ettingshausen, and Joule effects come into play in the energy balance. The region close to the liner is governed by thermal conduction, while the Joule dissipation becomes predominant far from it when the pressure ratio is low. Mass ablation, thermal energy, and magnetic flux losses are reduced with plasma magnetization, characterized by the electron Hall parameter ω e τ e , until β values of order unity are reached. From this point forward, increasing the electron Hall parameter no longer improves the magnetic flux conservation, and mass ablation is enhanced due to the magnetic pressure gradients. A thoughtful simplification of the problem that allows to reduce the order of the system of governing equations while still retaining the finite β effects is presented and compared to the exact case.

  1. Autofrettage to Counteract Coefficient of Thermal Expansion Mismatch in Cryogenic Pressurized Pipes with Metallic Liners

    NASA Technical Reports Server (NTRS)

    Wen, Ed; Barbero, Ever; Tygielski, Phlip; Turner, James E. (Technical Monitor)

    2001-01-01

    Composite feedlines with metal liners have the potential to reduce weight/cost while providing the same level of permeation resistance and material compatibility of all-metal feedlines carrying cryogenic propellants in spacecraft. The major technical challenges are the large difference in Coefficient of Thermal Expansion between the liner and the composite, and the manufacturing method required to make a very thin liner with the required strength and dimensional tolerance. This study investigates the use of autofrettage (compressive preload) to counteract Coefficient of Thermal Expansion when pre-pressurization procedures cannot be used to solve this problem. Promising materials (aluminum 2219, Inconel 718, nickel, nickel alloy) and manufacturing techniques (chemical milling, electroplating) are evaluated to determine the best liner candidates. Robust, autofrettaged feedlines with a low Coefficient of Thermal Expansion liner (Inconel 718 or nickel alloy) are shown to successfully counteract mismatch at LOX temperature. A new concept, autofrettage by temperature, is introduced for high Coefficient of Thermal Expansion materials (aluminum and pure nickel) where pressure cannot be used to add compressive preload.

  2. One-dimensional magnetohydrodynamics of a cylindrical liner imploded by an azimuthal magnetic field and compressing an axial field

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

    Hamann, F., E-mail: franck.hamann@cea.fr; Combis, P.; Videau, L.

    The one-dimensional magnetohydrodynamics of a plasma cylindrical liner is addressed in the case of a two components magnetic field. The azimuthal component is responsible for the implosion of the liner and the axial field is compressed inside the liner. A complete set of analytical profiles for the magnetic field components, the density, and the local velocity are proposed at the scale of the liner thickness. Numerical simulations are also presented to test the validity of the analytical formulas.

  3. Findings from the X-33 Hydrogen Tank Failure Investigation

    NASA Technical Reports Server (NTRS)

    Niedermeyer, Melinda; Munafo, Paul M. (Technical Monitor)

    2001-01-01

    The X-33 Hydrogen tank failed during test in November of 1999 at MSFC. The tank completed the structural loading phase of the test successfully and was drained of hydrogen prior to the failure. The failure initiated in the acreage of Lobe 1 and was instantaneous, peeling the outer skin and core away from the inner skin. It was determined there were several factors that provided the opportunity for the tank to fail in this way. The factor giving life to these opportunistic circumstances was hydrogen infiltration into the core of the tank. The mechanism for this phenomenon will be discussed in this presentation.

  4. Effect of Different Liners on Fracture Resistance of Premolars Restored with Conventional and Short Fiber-Reinforced Composite Resins.

    PubMed

    Shafiei, Fereshteh; Doozandeh, Maryam; Ghaffaripour, Dordaneh

    2018-01-11

    To see whether applying four different liners under short fiber-reinforced composite (SFRC), everX Posterior, compared to conventional composite resin, Z250, affected their strengthening property in premolar MOD cavities. Mesio-occluso-distal (MOD) cavities were prepared in 120 sound maxillary premolars divided into 10 groups (n = 12) in terms of two composite resin types and 4 liners or no liner. For each composite resin, in 5 groups no liner, resin-modified glass ionomer (RMGI), conventional flowable composite (COFL), self-adhesive flowable composite resin (SAFL), and self-adhesive resin cement (SARC) were applied prior to restoring incrementally. After water storage and thermocycling, static fracture resistance was tested. Data (in Newtons) were analyzed using two-way ANOVA (α = 0.05). Fracture resistance was significantly affected by composite resin type (p = 0.02), but not by the liner (p > 0.05). The interaction of the two factors was not statistically significant (p > 0.05). SFRC exhibited higher fracture strength (1470 ± 200 N) compared to conventional composite resin (1350 ± 290), irrespective of the application of liners. Application of SARC and SAFL liners led to a higher number of restorable fractures for both composite resins. The four liners can be used without interfering with the higher efficacy of SFRC, compared to conventional composite resins, to improve the fracture strength of premolar MOD cavities. © 2018 by the American College of Prosthodontists.

  5. A Computational Study of the Flow Physics of Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Tam, Christopher

    2006-01-01

    The present investigation is a continuation of a previous joint project between the Florida State University and the NASA Langley Research Center Liner Physics Team. In the previous project, a study of acoustic liners, in two dimensions, inside a normal incidence impedance tube was carried out. The study consisted of two parts. The NASA team was responsible for the experimental part of the project. This involved performing measurements in an impedance tube with a large aspect ratio slit resonator. The FSU team was responsible for the computation part of the project. This involved performing direct numerical simulation (DNS) of the NASA experiment in two dimensions using CAA methodology. It was agreed that upon completion of numerical simulation, the computed values of the liner impedance were to be sent to NASA for validation with experimental results. On following this procedure good agreements were found between numerical results and experimental measurements over a wide range of frequencies and sound-pressure-level. Broadband incident sound waves were also simulated numerically and measured experimentally. Overall, good agreements were also found.

  6. Summary of JAYGO mixing and FSM-1 application of castable inhibitor and liner

    NASA Technical Reports Server (NTRS)

    Evans, Kurt B.

    1990-01-01

    Two JAYGO planetary mixers (12 and 42 gallon) are being qualified to mix STW5-3224 liner and STW5-3223 castable inhibitor. These mixers are an integral part of a mix process which allows for safe addition of the asbestos component. An essential part of the engineering evaluation (ETP-0347) of these mixers is the generation of static test fire data. Ultimately, these results will help confirm the adequacy of these mixers for production mixing of liner and inhibitor. (These data are not required for qualification of the Certification Test Plan CTP-0125). The details on the mixing, inhibiting, and sling-lining of JAYGO-mixed castable inhibitor and liner which were applied to the FSM-1 segments are presented. The objectives are the following: (1) to document processing events surrounding the JAYO mixing of castable inhibitor and liner, and the subsequent inhibiting and sling lining onto the FSM-1 segments; and (2) to substantiate the measured properties of these JAYGO-mixed materials (rheological and mechanical) and compare these properties to existing production database.

  7. Tank car accident data analysis

    DOT National Transportation Integrated Search

    1991-06-01

    This report presents the results of a study of accidents involving railroad tank cars. The study is part of an overall effort to provide improved safety of rail transportation at reduced life-cycle costs. A major goal of the study is to provide a tec...

  8. Large Engine Technology Program. Task 21: Rich Burn Liner for Near Term Experimental Evaluations

    NASA Technical Reports Server (NTRS)

    Hautman, D. J.; Padget, F. C.; Kwoka, D.; Siskind, K. S.; Lohmann, R. P.

    2005-01-01

    The objective of the task reported herein, which was conducted as part of the NASA sponsored Large Engine Technology program, was to define and evaluate a near-term rich-zone liner construction based on currently available materials and fabrication processes for a Rich-Quench-Lean combustor. This liner must be capable of operation at the temperatures and pressures of simulated HSCT flight conditions but only needs sufficient durability for limited duration testing in combustor rigs and demonstrator engines in the near future. This must be achieved at realistic cooling airflow rates since the approach must not compromise the emissions, performance, and operability of the test combustors, relative to the product engine goals. The effort was initiated with an analytical screening of three different liner construction concepts. These included a full cylinder metallic liner and one with multiple segments of monolithic ceramic, both of which incorporated convective cooling on the external surface using combustor airflow that bypassed the rich zone. The third approach was a metallic platelet construction with internal convective cooling. These three metal liner/jacket combinations were tested in a modified version of an existing Rich-Quench-Lean combustor rig to obtain data for heat transfer model refinement and durability verification.

  9. Hydrocarbon-fuel/combustion-chamber-liner materials compatibility

    NASA Technical Reports Server (NTRS)

    Gage, Mark L.

    1990-01-01

    Results of material compatibility experiments using hydrocarbon fuels in contact with copper-based combustion chamber liner materials are presented. Mil-Spec RP-1, n- dodecane, propane, and methane fuels were tested in contact with OFHC, NASA-Z, and ZrCu coppers. Two distinct test methods were employed. Static tests, in which copper coupons were exposed to fuel for long durations at constant temperature and pressure, provided compatibility data in a precisely controlled environment. Dynamic tests, using the Aerojet Carbothermal Test Facility, provided fuel and copper compatibility data under realistic booster engine service conditions. Tests were conducted using very pure grades of each fuel and fuels to which a contaminant, e.g., ethylene or methyl mercaptan, was added to define the role played by fuel impurities. Conclusions are reached as to degradation mechanisms and effects, methods for the elimination of these mechanisms, selection of copper alloy combustion chamber liners, and hydrocarbon fuel purchase specifications.

  10. Magnesium fluoride reduction-vessel liners. Final report

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

    Latham-Brown, C.E.

    1986-03-26

    The work described in this report details a program that demonstrated a method by which magnesium fluoride, the by-product of the reduction reaction of uranium tetrafluoride to uranium metal could be used to replace the present graphite used to line the reduction vessel. Utilization of magnesium fluoride (MgF2) as a reduction-vessel liner has the potential to decrease carbon contamination and thereby reduce DU derby rejects due to chemistry. Additionally, there would be the elimination of the cost of the graphite crucible liner and the associated disposal costs by replacement with the by-product of the reduction reaction, which is magnesium fluoride.more » The process would ultimately result in reduced manufacturing costs for derby metal and higher yield of finished penetrators. This was to be accomplished in such a manner as to produce uranium metal derbies which would be accommodated into the present Nuclear Metals-Carolina Metals penetrator production process with minimal changes in equipment and procedures.« less

  11. Plasma-Jet-Driven Magneto-Inertial Fusion (PJMIF): Physics and Design for a Plasma Liner Formation Experiment

    NASA Astrophysics Data System (ADS)

    Hsu, Scott; Cassibry, Jason; Witherspoon, F. Douglas

    2014-10-01

    Spherically imploding plasma liners are a potential standoff compression driver for magneto-inertial fusion, which is a hybrid of and operates in an intermediate density between those of magnetic and inertial fusion. We propose to use an array of merging supersonic plasma jets to form a spherically imploding plasma liner. The jets are to be formed by pulsed coaxial guns with contoured electrodes that are placed sufficiently far from the location of target compression such that no hardware is repetitively destroyed. As such, the repetition rate can be higher (e.g., 1 Hz) and ultimately the power-plant economics can be more attractive than most other MIF approaches. During the R&D phase, a high experimental shot rate at reasonably low cost (e.g., < 1 k/shot) may be achieved with excellent diagnostic access, thus enabling a rapid learning rate. After some background on PJMIF and its prospects for reactor-relevant energy gain, this poster describes the physics objectives and design of a proposed 60-gun plasma-liner-formation experiment, which will provide experimental data on: (i) scaling of peak liner ram pressure versus initial jet parameters, (ii) liner non-uniformity characterization and control, and (iii) control of liner profiles for eventual gain optimization.

  12. Micro-beam friction liner and method of transferring energy

    DOEpatents

    Mentesana, Charles [Leawood, KS

    2007-07-17

    A micro-beam friction liner adapted to increase performance and efficiency and reduce wear in a piezoelectric motor or actuator or other device using a traveling or standing wave to transfer energy in the form of torque and momentum. The micro-beam friction liner comprises a dense array of micro-beam projections having first ends fixed relative to a rotor and second ends projecting substantially toward a plurality of teeth of a stator, wherein the micro-beam projections are compressed and bent during piezoelectric movement of the stator teeth, thereby storing the energy, and then react against the stator teeth to convert the stored energy stored to rotational energy in the rotor.

  13. Issues with Strong Compression of Plasma Target by Stabilized Imploding Liner

    NASA Astrophysics Data System (ADS)

    Turchi, Peter; Frese, Sherry; Frese, Michael

    2017-10-01

    Strong compression (10:1 in radius) of an FRC by imploding liquid metal liners, stabilized against Rayleigh-Taylor modes, using different scalings for loss based on Bohm vs 100X classical diffusion rates, predict useful compressions with implosion times half the initial energy lifetime. The elongation (length-to-diameter ratio) near peak compression needed to satisfy empirical stability criterion and also retain alpha-particles is about ten. The present paper extends these considerations to issues of the initial FRC, including stability conditions (S*/E) and allowable angular speeds. Furthermore, efficient recovery of the implosion energy and alpha-particle work, in order to reduce the necessary nuclear gain for an economical power reactor, is seen as an important element of the stabilized liner implosion concept for fusion. We describe recent progress in design and construction of the high energy-density prototype of a Stabilized Liner Compressor (SLC) leading to repetitive laboratory experiments to develop the plasma target. Supported by ARPA-E ALPHA Program.

  14. Simulation Study of Structure and Properties of Plasma Liners for the PLX- α Project

    NASA Astrophysics Data System (ADS)

    Samulyak, Roman; Shih, Wen; Hsu, Scott; PLX-Alpha Team

    2017-10-01

    Detailed numerical studies of the propagation and merger of high-Mach-number plasma jets and the formation and implosion of plasma liners have been performed using the FronTier code in support of the Plasma Liner Experiment-ALPHA (PLX- α) project. Physics models include radiation, physical diffusion, plasma-EOS models, and an anisotropic diffusion model that mimics deviations from fully collisional hydrodynamics in outer layers of plasma jets. Detailed structure and non-uniformity of plasma liners of due to primary and secondary shock waves have been studies as well as averaged quantities of ram pressure and Mach number. Synthetic data from simulations have been compared with available experimental data from a multi-chord interferometer and survey and high-resolution spectrometers. Numerical studies of the sensitivity of liner properties to experimental errors in the initial masses of jets and the synchronization of plasma gun valves have also been performed. Supported by the ARPA-E ALPHA program.

  15. Formation of metal and dielectric liners using a solution process for deep trench capacitors.

    PubMed

    Ham, Yong-Hyun; Kim, Dong-Pyo; Baek, Kyu-Ha; Park, Kun-Sik; Kim, Moonkeun; Kwon, Kwang-Ho; Shin, Hong-Sik; Lee, Kijun; Do, Lee-Mi

    2012-07-01

    We demonstrated the feasibility of metal and dielectric liners using a solution process for deep trench capacitor application. The deep Si trench via with size of 10.3 microm and depth of 71 microm were fabricated by Bosch process in deep reactive ion etch (DRIE) system. The aspect ratio was about 7. Then, nano-Ag ink and poly(4-vinylphenol) (PVPh) were used to form metal and dielectric liners, respectively. The thicknesses of the Ag and PVPh liners were about 144 and 830 nm, respectively. When the curing temperature of Ag film increased from 120 to 150 degrees C, the sheet resistance decreased rapidly from 2.47 to 0.72 Omega/sq and then slightly decreased to 0.6 Omega/sq with further increasing the curing temperature beyond 150 degrees C. The proposed liner formation method using solution process is a simple and cost effective process for the high capacity of deep trench capacitor.

  16. Wear versus Thickness and Other Features of 5-Mrad Crosslinked UHMWPE Acetabular Liners

    PubMed Central

    Shen, Fu-Wen; Lu, Zhen

    2010-01-01

    Background The low wear rates of crosslinked polyethylenes provide the potential to use larger diameters to resist dislocation. However, this requires the use of thinner liners in the acetabular component, with concern that higher contact stresses will increase wear, offsetting the benefits of the crosslinking. Questions/purposes We asked the following questions: Is the wear of conventional and crosslinked polyethylene liners affected by ball diameter, rigidity of backing, and liner thickness? Are the stresses in the liner affected by thickness? Methods Wear rates were measured in a hip simulator and stresses were calculated using finite element modeling. Results Without crosslinking, the wear rate was 4% to 10% greater with a 36-mm diameter than a 28-mm diameter. With crosslinking, wear was 9% lower with a 36-mm diameter without metal backing and 4% greater with metal backing. Reducing the thickness from 6 mm to 3 mm increased the contact stress by 46%, but the wear rate decreased by 19%. Conclusions The reduction in wear with 5 Mrad of crosslinking was not offset by increasing the diameter from 28 mm to 36 mm or by using a liner as thin as 3 mm. Clinical Relevance The results indicate, for a properly positioned 5-Mrad crosslinked acetabular component and within the range of dimensions evaluated, neither wear nor stresses in the polyethylene are limiting factors in the use of larger-diameter, thinner cups to resist dislocation. PMID:20848244

  17. A semi-analytic model of magnetized liner inertial fusion

    DOE PAGES

    McBride, Ryan D.; Slutz, Stephen A.

    2015-05-21

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primarymore » fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.« less

  18. A semi-analytic model of magnetized liner inertial fusion

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

    McBride, Ryan D.; Slutz, Stephen A.

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primarymore » fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.« less

  19. A finite element model to assess transtibial prosthetic sockets with elastomeric liners.

    PubMed

    Cagle, John C; Reinhall, Per G; Allyn, Kate J; McLean, Jake; Hinrichs, Paul; Hafner, Brian J; Sanders, Joan E

    2017-12-13

    People with transtibial amputation often experience skin breakdown due to the pressures and shear stresses that occur at the limb-socket interface. The purpose of this research was to create a transtibial finite element model (FEM) of a contemporary prosthesis that included complete socket geometry, two frictional interactions (limb-liner and liner-socket), and an elastomeric liner. Magnetic resonance imaging scans from three people with characteristic transtibial limb shapes (i.e., short-conical, long-conical, and cylindrical) were acquired and used to develop the models. Each model was evaluated with two loading profiles to identify locations of focused stresses during stance phase. The models identified five locations on the participants' residual limbs where peak stresses matched locations of mechanically induced skin issues they experienced in the 9 months prior to being scanned. The peak contact pressure across all simulations was 98 kPa and the maximum resultant shear stress was 50 kPa, showing reasonable agreement with interface stress measurements reported in the literature. Future research could take advantage of the developed FEM to assess the influence of changes in limb volume or liner material properties on interface stress distributions. Graphical abstract Residual limb finite element model. Left: model components. Right: interface pressures during stance phase.

  20. Method and apparatus for monitoring the integrity of a geomembrane liner using time domain reflectometry

    DOEpatents

    Morrison, John L [Idaho Falls, ID

    2001-04-24

    Leaks are detected in a multi-layered geomembrane liner by a two-dimensional time domain reflectometry (TDR) technique. The TDR geomembrane liner is constructed with an electrically conductive detection layer positioned between two electrically non-conductive dielectric layers, which are each positioned between the detection layer and an electrically conductive reference layer. The integrity of the TDR geomembrane liner is determined by generating electrical pulses within the detection layer and measuring the time delay for any reflected electrical energy caused by absorption of moisture by a dielectric layer.

  1. Method and Apparatus for Monitoring the Integrity of a Geomembrane Liner using time Domain Reflectometry

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

    Morris, John L.

    1998-11-09

    Leaks are detected in a multi-layered geomembrane liner by a two-dimensional time domain reflectometry (TDR) technique. The TDR geomembrane liner is constructed with an electrically conductive detection layer positioned between two electrically non-conductive dielectric layers, which are each positioned between the detection layer and an electrically conductive reference layer. The integrity of the TDR geomembrane liner is determined by generating electrical pulses within the detection layer and measuring the time delay for any reflected electrical energy caused by absorption of moisture by a dielectric layer.

  2. Investigation of Spheromak Plasma Cooling through Metallic Liner Spallation during Compression

    NASA Astrophysics Data System (ADS)

    Ross, Keeton; Mossman, Alex; Young, William; Ivanov, Russ; O'Shea, Peter; Howard, Stephen

    2016-10-01

    Various magnetic-target fusion (MTF) reactor concepts involve a preliminary magnetic confinement stage, followed by a metallic liner implosion that compresses the plasma to fusion conditions. The process is repeated to produce a pulsed, net-gain energy system. General Fusion, Inc. is pursuing one scheme that involves the compression of spheromak plasmas inside a liner formed by a collapsing vortex of liquid Pb-Li. The compression is driven by focused acoustic waves launched by gas-driven piston impacts. Here we describe a project to exploring the effects of possible liner spallation during compression on the spheromaks temperature, lifetime, and stability. We employ a 1 J, 10 ns pulsed YAG laser at 532nm focused onto a thin film of Li or Al to inject a known quantity of metallic impurities into a spheromak plasma and then measure the response. Diagnostics including visible and ultraviolet spectrometers, ion Doppler, B-probes, and Thomson scattering are used for plasma characterization. We then plan to apply the trends measured under these controlled conditions to evaluate the role of wall impurities during `field shots', where spheromaks are compressed through a chemically driven implosion of an aluminum flux conserver. The hope is that with further study we could more accurately include the effect of wall impurities on the fusion yield of a reactor-scale MTF system. Experimental procedures and results are presented, along with their relation to other liner-driven, MTF schemes. -/a

  3. Tanks focus area multiyear program plan FY97-FY99

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

    NONE

    1996-08-01

    The U.S. Department of Energy (DOE) continues to face a major tank remediation problem with approximately 332 tanks storing over 378,000 ml of high-level waste (HLW) and transuranic (TRU) waste across the DOE complex. Most of the tanks have significantly exceeded their life spans. Approximately 90 tanks across the DOE complex are known or assumed to have leaked. Some of the tank contents are potentially explosive. These tanks must be remediated and made safe. How- ever, regulatory drivers are more ambitious than baseline technologies and budgets will support. Therefore, the Tanks Focus Area (TFA) began operation in October 1994. Themore » focus area manages, coordinates, and leverages technology development to provide integrated solutions to remediate problems that will accelerate safe and cost-effective cleanup and closure of DOE`s national tank system. The TFA is responsible for technology development to support DOE`s four major tank sites: Hanford Site (Washington), INEL (Idaho), Oak Ridge Reservation (ORR) (Tennessee), and Savannah River Site (SRS) (South Carolina). Its technical scope covers the major functions that comprise a complete tank remediation system: safety, characterization, retrieval, pretreatment, immobilization, and closure.« less

  4. Hanford Double-Shell Tank Inspection Annual Report Calendar Year 2012

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

    Petermann, Tasha M.; Boomer, Kayle D.; Washenfelder, D. J.

    2013-12-02

    The double-shell tanks (DSTs) were constructed between 1968 and 1986. They will have exceeded their design life before the waste can be removed and trasferred to the Waste Treatment and Immobilization Plant for vitrification. The Double-Shell Tank Integrity Project has been established to evaluate tank aging, and ensure that each tank is structurally sound for continued use. This is the first issue of the Double-Shell Tank Inspection Annual Report. The purpose of this issue is to summarize the results of DST inspections conducted from the beginnng of the inspection program through the end of CY2012. Hereafter, the report will bemore » updated annually with summaries of the past year's DST inspection activities.« less

  5. Survey of Technologies for Monitoring Containment Liners and Covers

    EPA Pesticide Factsheets

    The report provides information on innovative long-term monitoring technologies to detect contaminant releases beneath a liner containment system and identify potential problems with the integrity of final containment covers.

  6. Lunar habitat concept employing the space shuttle external tank.

    PubMed

    King, C B; Butterfield, A J; Hypes, W D; Nealy, J E; Simonsen, L C

    1990-01-01

    The space shuttle external tank, which consists of a liquid oxygen tank, an intertank structure, and a liquid hydrogen tank, is an expendable structure used for approximately 8.5 min during each launch. A concept for outfitting the liquid oxygen tank-intertank unit for a 12-person lunar habitat is described. The concept utilizes existing structures and openings for both man and equipment access without compromising the structural integrity of the tank. Living quarters, instrumentation, environmental control and life support, thermal control, and propulsion systems are installed at Space Station Freedom. The unmanned habitat is then transported to low lunar orbit and autonomously soft landed on the lunar surface. Design studies indicate that this concept is feasible by the year 2000 with concurrent development of a space transfer vehicle and manned cargo lander for crew changeover and resupply.

  7. The effect of denture base surface pretreatments on bond strengths of two long term resilient liners

    PubMed Central

    Parkhedkar, Rambhau

    2011-01-01

    PURPOSE Purpose of this study was to evaluate effect of two surface treatments, sandblasting and monomer treatment, on tensile bond strength between two long term resilient liners and poly (methyl methacrylate) denture base resin. MATERIALS AND METHODS Two resilient liners Super-Soft and Molloplast-B were selected.Sixty acrylic resin (Trevalon) specimens with cross sectional area of 10×10 mm were prepared and divided into two groups of 30 specimens each. Each group was surface treated (n = 10) by sandblasting (250 µ alumina particles), monomer treatment (for 180 sec) and control (no surface treatment). Resilient liners were processed between 2 poly(methyl methacrylate) surfaces, in the dimensions of 10×10×3 mm. Tensile strength was determined with Instron Universal testing machine, at a crosshead speed of 5 mm/min; and the modes of failure (adhesive, cohesive or mixed) were recorded. The data were analyzed using one-way ANOVA, followed by Tukey HSD test (α = 0.05). RESULTS Monomer pretreatment of acrylic resin produced significantly higher bond strengths when compared to sandblasting and control for both resilient liners (P < .001). Sandblasting significantly decreased the bond strength for both the liners when compared to monomer pretreatment and control (P < .001). Mean bond strength of Super-Soft lined specimens was significantly higher than Molloplast-B in various surface treatment groups (P < .05). CONCLUSION Surface pretreatment of the acrylic resin with monomer prior to resilient liner application is an effective method to increase bond strength between the base and soft liner. Sandblasting, on the contrary, is not recommended as it weakens the bond between the two. PMID:21503188

  8. Recyclability of mixed office waste papers containing pressure sensitive adhesives and silicone release liners

    Treesearch

    Julie Hess; Roberta Sena-Gomes; Lisa Davie; Marguerite Sykes

    2001-01-01

    Increased use of pressure sensitive adhesives for labels and stamps has introduced another contaminant into the office paper stream: silicone- coated release liners. This study examines methods and conditions for removal of contaminants, including these liners, from a typical batch of discarded office papers. Removal of contaminants contained in the furnish were...

  9. Evaluation of two polyimides and of an improved liner retention design for self-lubricating bushings

    NASA Technical Reports Server (NTRS)

    Sliney, H. E.

    1984-01-01

    Two different polyimide polymers were studied and the effectiveness of a design feature to improve retention of the self lubricating composite liners under high load was evaluated. The basic bearing design consisted of a molded layer of chopped graphite-fiber-reinforced-polyimide (GFRP) composite bonded to the bore of a steel bushing. The friction, wear, and load carrying ability of the bushings were determined in oscillating tests at 25, 260 and 315 C at radial unit loads up to 260 MPa. Friction coefficients were typically 0.15 to 0.25. Bushings with liners containing a new partially fluorinated polymer were functional, but had a lower load capacity and higher wear rate than those containing a more conventional, high temperature polyimide. The liner retention design feature reduced the tendency of the liners to crack and work out of the contact zone under high oscillating loads.

  10. Adaptive Back Sheet Material for Acoustic Liner Applications-ARMD Seedling Fund Phase I Final Report

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Jones, Michael G.; Farrar, Dawnielle

    2014-01-01

    A recently developed piezo-electric composite film is evaluated for its usefulness in application in acoustic liners. Researchers at the NASA Langley Research Center Liner Technology Facility developed experiments to measure the electrical response of the material to acoustic excitation and the vibrational response of the material to electrical excitation. The robustness of the piezo-electric film was also assessed. The material's electrical response to acoustic excitation is found to be comparable to a commercial microphone in the range of frequencies from 500 to 3000 Hz. However, the vibrational response to electrical excitation in the frequency range of interest is an order of magnitude less than may be necessary for application to acoustic liners. Nevertheless, experimental results indicate that the potential exists for the material to produce a measurable change in the impedance spectrum of a liner. Work continues to improve the authority of the piezo-electric film.

  11. Transition duct system with metal liners for delivering hot-temperature gases in a combustion turbine engine

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

    Wiebe, David J.

    A transition duct system (10) for delivering hot-temperature gases from a plurality of combustors in a combustion turbine engine is provided. The system includes an exit piece (16) for each combustor. The exit piece may include a straight path segment (26) and an arcuate connecting segment (36). A respective straight metal liner (92) and an arcuate metal liner (94) may be each inwardly disposed onto a metal outer shell (38) along the straight path segment and the arcuate connecting segment (36) of the exit piece. Structural arrangements are provided to securely attach the respective liners in the presence of substantialmore » flow path pressurization. Cost-effective serviceability of the transition duct systems is realizable since the liners can be readily removed and replaced as needed.« less

  12. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

    NASA Astrophysics Data System (ADS)

    Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.; Jordan, N. M.; Lau, Y. Y.; Gilgenbach, R. M.

    2015-11-01

    In this work, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ˜600 kA with ˜200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. This technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.

  13. The Usability of a Pressure-Indicating Film to Measure the Teat Load Caused by a Collapsing Liner

    PubMed Central

    Demba, Susanne; Elsholz, Sabrina; Ammon, Christian; Rose-Meierhöfer, Sandra

    2016-01-01

    Prevention of damage to the teat and mastitis requires determination of the teat load caused by a collapsing liner. The aim of this study was to test a pressure-indicating film designed to measure the pressure between a collapsing liner and artificial teats. The Ultra Super Low and the Extreme Low pressure-indicating films were tested on two types of artificial teat. The experiments were performed with a conventional milking cluster equipped with round silicone liners. For each teat and film type, 30 repetitions were performed. Each repetition was performed with a new piece of film. Kruskal-Wallis tests were performed to detect differences between the pressure values for the different teats. The area of regions where pressure-indication color developed was calculated to determine the most suitable film type. Both film types measured the pressure applied to both artificial teats by the teat cup liner. Thus, the pressure-indicating films can be used to measure the pressure between a collapsing liner and an artificial teat. Based on the results of the present investigation, a pressure-indicating film with the measurement ranges of both film types combined would be an optimal tool to measure the overall pressure between an artificial teat and a collapsing liner. PMID:27690033

  14. Purpose-built PDC bit successfully drills 7-in liner equipment and formation: An integrated solution

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

    Puennel, J.G.A.; Huppertz, A.; Huizing, J.

    1996-12-31

    Historically, drilling out the 7-in, liner equipment has been a time consuming operation with a limited success ratio. The success of the operation is highly dependent on the type of drill bit employed. Tungsten carbide mills and mill tooth rock bits required from 7.5 to 11.5 hours respectively to drill the pack-off bushings, landing collar, shoe track and shoe. Rates of penetration dropped dramatically when drilling the float equipment. While conventional PDC bits have drilled the liner equipment successfully (averaging 9.7 hours), severe bit damage invariably prevented them from continuing to drill the formation at cost-effective penetration rates. This papermore » describes the integrated development and application of an IADC M433 Class PDC bit, which was designed specifically to drill out the 7-in. liner equipment and continue drilling the formation at satisfactory penetration rates. The development was the result of a joint investigation There the operator and bit/liner manufacturers shared their expertise in solving a drilling problem, The heavy-set bit was developed following drill-off tests conducted to investigate the drillability of the 7-in. liner equipment. Key features of the new bit and its application onshore The Netherlands will be presented and analyzed.« less

  15. X-ray Measurements of Laser Irradiated Foam Filled Liners

    NASA Astrophysics Data System (ADS)

    Patankar, Siddharth; Mariscal, Derek; Goyon, Clement; Baker, Kevin; MacLaren, Stephan; Hammer, Jim; Baumann, Ted; Amendt, Peter; Menapace, Joseph; Berger, Bob; Afeyan, Bedros; Tabak, Max; Dixit, Sham; Kim, Sung Ho; Moody, John; Jones, Ogden

    2016-10-01

    Low-density foam liners are being investigated as sources of efficient x-rays. Understanding the laser-foam interaction is key to modeling and optimizing foam composition and density for x-ray production with reduced backscatter. We report on the experimental results of laser-irradiated foam liners filled with SiO2 and Ta2O5 foams at densities between 2 to 30mg/cc. The foam liners consist of polyimide tubes filled with low-density foams and sealed with a gold foil at one end. The open end of the tube is driven with 250J of 527nm laser light in a 2ns 2-step pulse using the Jupiter Laser Facility at LLNL. A full aperture backscatter system is used to diagnose the coupled energy and losses. A streaked x-ray camera and filtered x-ray pinhole cameras are used to measure laser penetration into the low-density foam for different mass densities. A HOPG crystal spectrometer is used to estimate a thermal electron temperature. Comparisons with beam propagation and x-ray emission simulations are presented. This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, with funding support from the Laboratory Directed Research and Development Program under project 15.

  16. Duct modes damping through an adjustable electroacoustic liner under grazing incidence

    NASA Astrophysics Data System (ADS)

    Boulandet, R.; Lissek, H.; Karkar, S.; Collet, M.; Matten, G.; Ouisse, M.; Versaevel, M.

    2018-07-01

    This paper deals with active sound attenuation in lined ducts with flow and its application to duct modes damping in aircraft engine nacelles. It presents an active lining concept based on an arrangement of electroacoustic absorbers flush mounted in the duct wall. Such feedback-controlled loudspeaker membranes are used to achieve locally reacting impedances with adjustable resistance and reactance. A broadband impedance model is formulated from the loudspeaker parameters and a design procedure is proposed to achieve specified acoustic resistances and reactances. The performance is studied for multimodal excitation by simulation using the finite element method and the results are compared to measurements made in a flow duct facility. This electroacoustic liner has an attenuation potential comparable to that of a conventional passive liner, but also offers greater flexibility to achieve the target acoustic impedance in the low frequencies. In addition, it is adaptive in real time to track variable engine speeds. It is shown with the liner prototype that the duct modes can be attenuated over a bandwidth of two octaves around the resonance frequency of the loudspeakers.

  17. The impact of different types of textile liners used in protective footwear on the subjective sensations of firefighters.

    PubMed

    Irzmańska, Emilia

    2015-03-01

    The paper presents ergonomic evaluation of footwear used with three types of textile liners differing in terms of design and material composition. Two novel textile composite liners with enhanced hygienic properties were compared with a standard liner used in firefighter boots. The study involved 45 healthy firefighters from fire and rescue units who wore protective footwear with one of the three types of liners. The study was conducted in a laboratory under a normal atmosphere. The ergonomic properties of the protective footwear and liners were evaluated according to the standard EN ISO 20344:2012 as well as using an additional questionnaire concerning the thermal and moisture sensations experienced while wearing the footwear. The study was conducted on a much larger group of subjects (45) than that required by the ISO standard (3) to increase the reliability of subjective evaluations. Some statistically significant differences were found between the different types of textile liners used in firefighter boots. It was confirmed that the ergonomic properties of protective footwear worn in the workplace may be improved by the use of appropriate textile components. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  18. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

    DOE PAGES

    Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.; ...

    2015-11-19

    In this study, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ~600 kA with ~200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. As amore » result, this technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.« less

  19. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

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

    Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.

    In this study, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ~600 kA with ~200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. As amore » result, this technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.« less

  20. The PLX- α project: demonstrating the viability of spherically imploding plasma liners as an MIF driver

    NASA Astrophysics Data System (ADS)

    Hsu, S. C.; Witherspoon, F. D.; Cassibry, J. T.; Gilmore, M.; Samulyak, R.; Stoltz, P.; the PLX-α Team

    2015-11-01

    Under ARPA-E's ALPHA program, the Plasma Liner Experiment-ALPHA (PLX- α) project aims to demonstrate the viability and scalability of spherically imploding plasma liners as a standoff, high-implosion-velocity magneto-inertial-fusion (MIF) driver that is potentially compatible with both low- and high- β targets. The project has three major objectives: (a) advancing existing contoured-gap coaxial-gun technology to achieve higher operational reliability/precision and better control/reproducibility of plasma-jet properties and profiles; (2) conducting ~ π / 2 -solid-angle plasma-liner experiments with 9 guns to demonstrate (along with extrapolations from modeling) that the jet-merging process leads to Mach-number degradation and liner uniformity that are acceptable for MIF; and (3) conducting 4 π experiments with up to 60 guns to demonstrate the formation of an imploding spherical plasma liner for the first time, and to provide empirical ram-pressure and uniformity scaling data for benchmarking our codes and informing us whether the scalings justify further development beyond ALPHA. This talk will provide an overview of the PLX- α project as well as key research results to date. Supported by ARPA-E's ALPHA program; original PLX construction supported by DOE Fusion Energy Sciences.

  1. Megagauss-level magnetic field production in cm-scale auto-magnetizing helical liners pulsed to 500 kA in 125 ns

    NASA Astrophysics Data System (ADS)

    Shipley, G. A.; Awe, T. J.; Hutsel, B. T.; Slutz, S. A.; Lamppa, D. C.; Greenly, J. B.; Hutchinson, T. M.

    2018-05-01

    Auto-magnetizing (AutoMag) liners [Slutz et al., Phys. Plasmas 24, 012704 (2017)] are designed to generate up to 100 T of axial magnetic field in the fuel for Magnetized Liner Inertial Fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010)] without the need for external field coils. AutoMag liners (cylindrical tubes) are composed of discrete metallic helical conduction paths separated by electrically insulating material. Initially, helical current in the AutoMag liner produces internal axial magnetic field during a long (100 to 300 ns) current prepulse with an average current rise rate d I / d t = 5 k A / n s . After the cold fuel is magnetized, a rapidly rising current ( 200 k A / n s ) generates a calculated electric field of 64 M V / m between the helices. Such field is sufficient to force dielectric breakdown of the insulating material after which liner current is reoriented from helical to predominantly axial which ceases the AutoMag axial magnetic field production mechanism and the z-pinch liner implodes. Proof of concept experiments have been executed on the Mykonos linear transformer driver to measure the axial field produced by a variety of AutoMag liners and to evaluate what physical processes drive dielectric breakdown. A range of field strengths have been generated in various cm-scale liners in agreement with magnetic transient simulations including a measured field above 90 T at I = 350 kA. By varying the helical pitch angle, insulator material, and insulator geometry, favorable liner designs have been identified for which breakdown occurs under predictable and reproducible field conditions.

  2. UNVEILING THE PHYSICS OF LOW-LUMINOSITY AGNs THROUGH X-RAY VARIABILITY: LINER VERSUS SEYFERT 2

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

    Hernández-García, L.; Masegosa, J.; Márquez, I.

    X-ray variability is very common in active galactic nuclei (AGNs), but these variations may not occur similarly in different families of AGNs. We aim to disentangle the structure of low-ionization nuclear emission-line regions (LINERs) compared to Seyfert 2s by the study of their spectral properties and X-ray variations. We assembled the X-ray spectral parameters and variability patterns, which were obtained from simultaneous spectral fittings. Major differences are observed in the X-ray luminosities and the Eddington ratios, which are higher in Seyfert 2s. Short-term X-ray variations were not detected, while long-term changes are common in LINERs and Seyfert 2s. Compton-thick sourcesmore » generally do not show variations, most probably because the AGN is not accesible in the 0.5–10 keV energy band. The changes are mostly related to variations in the nuclear continuum, but other patterns of variability show that variations in the absorbers and at soft energies can be present in a few cases. We conclude that the X-ray variations may occur similarly in LINERs and Seyfert 2s, i.e., they are related to the nuclear continuum, although they might have different accretion mechanisms. Variations at UV frequencies are detected in LINER nuclei but not in Seyfert 2s. This is suggestive of at least some LINERs having an unobstructed view of the inner disk where the UV emission might take place, with UV variations being common in them. This result might be compatible with the disappeareance of the torus and/or the broad-line region in at least some LINERs.« less

  3. Demonstration of laser speckle system on burner liner cyclic rig

    NASA Technical Reports Server (NTRS)

    Stetson, K. A.

    1986-01-01

    A demonstration test was conducted to apply speckle photogrammetry to the measurement of strains on a sample of combustor liner material in a cyclic fatigue rig. A system for recording specklegrams was assembled and shipped to the NASA Lewis Research Center, where it was set up and operated during rig tests. Data in the form of recorded specklegrams were sent back to United Technologies Research Center for processing to extract strains. Difficulties were found in the form of warping and bowing of the sample during the tests which degraded the data. Steps were taken by NASA personnel to correct this problem and further tests were run. Final data processing indicated erratic patterns of strain on the burner liner sample.

  4. Dynamic Response and Residual Helmet Liner Crush Using Cadaver Heads and Standard Headforms.

    PubMed

    Bonin, S J; Luck, J F; Bass, C R; Gardiner, J C; Onar-Thomas, A; Asfour, S S; Siegmund, G P

    2017-03-01

    Biomechanical headforms are used for helmet certification testing and reconstructing helmeted head impacts; however, their biofidelity and direct applicability to human head and helmet responses remain unclear. Dynamic responses of cadaver heads and three headforms and residual foam liner deformations were compared during motorcycle helmet impacts. Instrumented, helmeted heads/headforms were dropped onto the forehead region against an instrumented flat anvil at 75, 150, and 195 J. Helmets were CT scanned to quantify maximum liner crush depth and crush volume. General linear models were used to quantify the effect of head type and impact energy on linear acceleration, head injury criterion (HIC), force, maximum liner crush depth, and liner crush volume and regression models were used to quantify the relationship between acceleration and both maximum crush depth and crush volume. The cadaver heads generated larger peak accelerations than all three headforms, larger HICs than the International Organization for Standardization (ISO), larger forces than the Hybrid III and ISO, larger maximum crush depth than the ISO, and larger crush volumes than the DOT. These significant differences between the cadaver heads and headforms need to be accounted for when attempting to estimate an impact exposure using a helmet's residual crush depth or volume.

  5. A Comparison Study of Normal-Incidence Acoustic Impedance Measurements of a Perforate Liner

    NASA Technical Reports Server (NTRS)

    Schultz, Todd; Liu, Fei; Cattafesta, Louis; Sheplak, Mark; Jones, Michael

    2009-01-01

    The eduction of the acoustic impedance for liner configurations is fundamental to the reduction of noise from modern jet engines. Ultimately, this property must be measured accurately for use in analytical and numerical propagation models of aircraft engine noise. Thus any standardized measurement techniques must be validated by providing reliable and consistent results for different facilities and sample sizes. This paper compares normal-incidence acoustic impedance measurements using the two-microphone method of ten nominally identical individual liner samples from two facilities, namely 50.8 mm and 25.4 mm square waveguides at NASA Langley Research Center and the University of Florida, respectively. The liner chosen for this investigation is a simple single-degree-of-freedom perforate liner with resonance and anti-resonance frequencies near 1.1 kHz and 2.2 kHz, respectively. The results show that the ten measurements have the most variation around the anti-resonance frequency, where statistically significant differences exist between the averaged results from the two facilities. However, the sample-to-sample variation is comparable in magnitude to the predicted cross-sectional area-dependent cavity dissipation differences between facilities, providing evidence that the size of the present samples does not significantly influence the results away from anti-resonance.

  6. Mathematical Modelling of Liner Piston Maintenance Activity using Field Data to Minimize Overhauling Time and Human Energy Consumption

    NASA Astrophysics Data System (ADS)

    Belkhode, Pramod Namdeorao

    2017-06-01

    Field data based model is proposed to reduce the overhauling time and human energy consumed in liner piston maintenance activity so as to increase the productivity of liner piston maintenance activity. The independent variables affecting the phenomenon such as anthropometric parameters of workers (Eastman Kodak Co. Ltd in Section VIA Appendix-A: Anthropometric Data. Ergonomic Design for People at Work, Van Nostrans Reinhold, New York, 1), workers parameters, specification of liner piston data, specification of tools used in liner piston maintenance activity, specification of solvents, axial clearance of big end bearing and bolt elongation, workstation data (Eastman Kodak Co. Ltd in Work Place Ergonomic Design for People at Work, Van Nostrans Reinhold, New York, 2) and extraneous variables, namely, temperature, humidity at workplace, illumination at workplace and noise at workplace (Eastman Kodak Co. Ltd in Chapter V Environment Ergonomic Design for People at Work, Van Nostrans Reinhold, New York, 3) are taken into account. The model is formulated for dependent variables of liner piston maintenance activity to minimize the overhauling time and human energy consumption so as to improve the productivity of liner piston maintenance activity. The developed model can predict the performance of liner piston maintenance activity which involves man and machine system (Schenck in Theories of Engineering Experimentation, Mc-Graw Hill, New York 4). The model is then optimized by optimization technique and the sensitivity analysis of the model has also been estimated.

  7. Liner cooling research at NASA Lewis Research Center. [for gas turbine combustion chambers

    NASA Technical Reports Server (NTRS)

    Acosta, Waldo A.

    1987-01-01

    Described are recently completed and current advanced liner research applicable to advanced small gas turbine engines. Research relating to the evolution of fuel efficient small gas turbine engines capable of meeting future commercial and military aviation needs is currently under way at NASA Lewis Research Center. As part of this research, a reverse-flow combustor geometry was maintained while different advanced liner wall cooling techniques were investigated and compared to a baseline combustor. The performance of the combustors featuring counterflow film-cooled (CFFC) panels, transpiration cooled liner walls (TRANS), and compliant metal/ceramic (CMC) walls was obtained over a range of simulated flight conditions of a 16:1 pressure ratio gas turbine engine and fuel/air ratios up to 0.034. All the combustors featured an identical fuel injection system, identical geometric configuration outline, and similar designed internal aerothermodynamics.

  8. Results From a Parametric Acoustic Liner Experiment Using P and W GEN1 HSR Mixer/Ejector Model

    NASA Technical Reports Server (NTRS)

    Boyd, Kathleen C.; Wolter, John D.

    2004-01-01

    This report documents the results of an acoustic liner test performed using a Gen 1 HSR mixer/ejector model installed on the Jet Exit Rig in the Nozzle Acoustic Test Rig in the Aeroacoustic Propulsion Laboratory or NASA Glenn Research Center. Acoustic liner effectiveness and single-component thrust performance results are discussed. Results from 26 different types of single-degree-of-freedom and bulk material liners are compared with each other and against a hardwall baseline. Design parameters involving all aspects of the facesheet, the backing cavity, and the type of bulk material were varied in order to study the effects of these design features on the acoustic impedance, acoustic effectiveness and on nozzle thrust performance. Overall, the bulk absorber liners are more effective at reducing the jet noise than the single-degree-of-freedom liners. Many of the design parameters had little effect on acoustic effectiveness, such as facesheeet hole diameter and honeycomb cell size. A relatively large variation in the impedance of the bulk absorber in a bulk liner is required to have a significant impact on the noise reduction. The thrust results exhibit a number of consistent trends, supporting the validity of this new addition to the facility. In general, the thrust results indicate that thrust performance benefits from increased facesheet thickness and decreased facesheet porosity.

  9. Slope Stability of Geosynthetic Clay Liner Test Plots

    EPA Science Inventory

    Fourteen full-scale field test plots containing five types of geosynthetic clay liners (GCLs) were constructed on 2H:IV and 3H:IV slopes for the purpose of assessing slope stability. The test plots were designed to simulate typical final cover systems for landfill. Slides occurr...

  10. Seismic Response Analysis of an Unanchored Steel Tank under Horizontal Excitation

    NASA Astrophysics Data System (ADS)

    Rulin, Zhang; Xudong, Cheng; Youhai, Guan

    2017-06-01

    The seismic performance of liquid storage tank affects the safety of people’s life and property. A 3-D finite element method (FEM) model of storage tank is established, which considers the liquid-solid coupling effect. Then, the displacement and stress distribution along the tank wall is studied under El Centro earthquake. Results show that, large amplitude sloshing with long period appears on liquid surface. The elephant-foot deformation occurs near the tank bottom, and at the elephant-foot deformation position maximum hoop stress and axial stress appear. The maximum axial compressive stress is very close to the allowable critical stress calculated by the design code, and may be local buckling failure occurs. The research can provide some reference for the seismic design of storage tanks.

  11. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  12. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  13. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  14. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  15. Megagauss-level magnetic field production in cm-scale auto-magnetizing helical liners pulsed to 500 kA in 125 ns

    DOE PAGES

    Shipley, Gabriel A.; Awe, Thomas James; Hutsel, Brian Thomas; ...

    2018-05-03

    We present Auto-magnetizing (AutoMag) liners [Slutz et al., Phys. Plasmas 24, 012704 (2017)] are designed to generate up to 100 T of axial magnetic field in the fuel for Magnetized Liner Inertial Fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010)] without the need for external field coils. AutoMag liners (cylindrical tubes) are composed of discrete metallic helical conduction paths separated by electrically insulating material. Initially, helical current in the AutoMag liner produces internal axial magnetic field during a long (100 to 300 ns) current prepulse with an average current rise rate dI/dt=5 kA/ns. After the cold fuel is magnetized,more » a rapidly rising current (200 kA/ns) generates a calculated electric field of 64 MV/m between the helices. Such field is sufficient to force dielectric breakdown of the insulating material after which liner current is reoriented from helical to predominantly axial which ceases the AutoMag axial magnetic field production mechanism and the z-pinch liner implodes. Proof of concept experiments have been executed on the Mykonos linear transformer driver to measure the axial field produced by a variety of AutoMag liners and to evaluate what physical processes drive dielectric breakdown. Lastly, a range of field strengths have been generated in various cm-scale liners in agreement with magnetic transient simulations including a measured field above 90 T at I = 350 kA. By varying the helical pitch angle, insulator material, and insulator geometry, favorable liner designs have been identified for which breakdown occurs under predictable and reproducible field conditions.« less

  16. Megagauss-level magnetic field production in cm-scale auto-magnetizing helical liners pulsed to 500 kA in 125 ns

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

    Shipley, Gabriel A.; Awe, Thomas James; Hutsel, Brian Thomas

    We present Auto-magnetizing (AutoMag) liners [Slutz et al., Phys. Plasmas 24, 012704 (2017)] are designed to generate up to 100 T of axial magnetic field in the fuel for Magnetized Liner Inertial Fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010)] without the need for external field coils. AutoMag liners (cylindrical tubes) are composed of discrete metallic helical conduction paths separated by electrically insulating material. Initially, helical current in the AutoMag liner produces internal axial magnetic field during a long (100 to 300 ns) current prepulse with an average current rise rate dI/dt=5 kA/ns. After the cold fuel is magnetized,more » a rapidly rising current (200 kA/ns) generates a calculated electric field of 64 MV/m between the helices. Such field is sufficient to force dielectric breakdown of the insulating material after which liner current is reoriented from helical to predominantly axial which ceases the AutoMag axial magnetic field production mechanism and the z-pinch liner implodes. Proof of concept experiments have been executed on the Mykonos linear transformer driver to measure the axial field produced by a variety of AutoMag liners and to evaluate what physical processes drive dielectric breakdown. Lastly, a range of field strengths have been generated in various cm-scale liners in agreement with magnetic transient simulations including a measured field above 90 T at I = 350 kA. By varying the helical pitch angle, insulator material, and insulator geometry, favorable liner designs have been identified for which breakdown occurs under predictable and reproducible field conditions.« less

  17. Development And Characterization Of A Liner-On-Target Injector For Staged Z-Pinch Experiments

    NASA Astrophysics Data System (ADS)

    Valenzuela, J. C.; Conti, F.; Krasheninnikov, I.; Narkis, J.; Beg, F.; Wessel, F. J.; Rahman, H. U.

    2016-10-01

    We present the design and optimization of a liner-on-target injector for Staged Z-pinch experiments. The injector is composed of an annular high atomic number (e.g. Ar, Kr) gas-puff and an on-axis plasma gun that delivers the ionized deuterium target. The liner nozzle injector has been carefully studied using Computational Fluid Dynamics (CFD) simulations to produce a highly collimated 1 cm radius gas profile that satisfies the theoretical requirement for best performance on the 1 MA Zebra current driver. The CFD simulations produce density profiles as a function of the nozzle shape and gas. These profiles are initialized in the MHD MACH2 code to find the optimal liner density for a stable, uniform implosion. We use a simple Snowplow model to study the plasma sheath acceleration in a coaxial plasma gun to help us properly design the target injector. We have performed line-integrated density measurements using a CW He-Ne laser to characterize the liner gas and the plasma gun density as a function of time. The measurements are compared with models and calculations and benchmarked accordingly. Advanced Research Projects Agency - Energy, DE-AR0000569.

  18. TankSIM: A Cryogenic Tank Performance Prediction Program

    NASA Technical Reports Server (NTRS)

    Bolshinskiy, L. G.; Hedayat, A.; Hastings, L. J.; Moder, J. P.; Schnell, A. R.; Sutherlin, S. G.

    2015-01-01

    Accurate prediction of the thermodynamic state of the cryogenic propellants in launch vehicle tanks is necessary for mission planning and successful execution. Cryogenic propellant storage and transfer in space environments requires that tank pressure be controlled. The pressure rise rate is determined by the complex interaction of external heat leak, fluid temperature stratification, and interfacial heat and mass transfer. If the required storage duration of a space mission is longer than the period in which the tank pressure reaches its allowable maximum, an appropriate pressure control method must be applied. Therefore, predictions of the pressurization rate and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning of future space exploration missions. This paper describes an analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. It is written in the FORTRAN 90 language and can be compiled with any Visual FORTRAN compiler. A thermodynamic vent system (TVS) is used to achieve tank pressure control. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, and mixing. Details of the TankSIM program and comparisons of its predictions with test data for liquid hydrogen and liquid methane will be presented in the final paper.

  19. Compact, Lightweight, Ceramic Matrix Composite (CMC) Based Acoustic Liners for Reducing Subsonic Jet Aircraft Engine Noise

    NASA Technical Reports Server (NTRS)

    Kiser, J. Douglas; Grady, Joseph E.; Miller, Christopher J.; Hultgren, Lennart S.; Jones, Michael G.

    2016-01-01

    Recent developments have reduced fan and jet noise contributions to overall subsonic aircraft jet-engine noise. Now, aircraft designers are turning their attention toward reducing engine core noise. The NASA Glenn Research Center and NASA Langley Research Center have teamed to investigate the development of a compact, lightweight acoustic liner based on oxide/oxide ceramic matrix composite (CMC) materials. The NASA team has built upon an existing oxide/oxide CMC sandwich structure concept that provides monotonal noise reduction. Oxide/oxide composites have good high temperature strength and oxidation resistance, which could allow them to perform as core liners at temperatures up to 1000C (1832F), and even higher depending on the selection of the composite constituents. NASA has initiated the evaluation of CMC-based liners that use cells of different lengths (variable-depth channels) or effective lengths to achieve broadband noise reduction. Reducing the overall liner thickness is also a major goal, to minimize the volume occupied by the liner. As a first step toward demonstrating the feasibility of our concepts, an oxide/oxide CMC acoustic testing article with different channel lengths was tested. Our approach, summary of test results, current status, and goals for the future are reported.

  20. Device and method for imploding a microsphere with a fast liner

    DOEpatents

    Thode, Lester E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner to drive the fast liner to implode a microsphere.

  1. 27 CFR 24.229 - Tank car and tank truck requirements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Tank car and tank truck... BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Spirits § 24.229 Tank car and tank truck requirements. Railroad tank cars and tank trucks used to transport spirits for use in wine production will be constructed...

  2. 27 CFR 24.229 - Tank car and tank truck requirements.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Tank car and tank truck... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.229 Tank car and tank truck requirements. Railroad tank cars and tank trucks used to transport spirits for use in wine production will be constructed...

  3. 27 CFR 24.229 - Tank car and tank truck requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Tank car and tank truck... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.229 Tank car and tank truck requirements. Railroad tank cars and tank trucks used to transport spirits for use in wine production will be constructed...

  4. 27 CFR 24.229 - Tank car and tank truck requirements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Tank car and tank truck... BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Spirits § 24.229 Tank car and tank truck requirements. Railroad tank cars and tank trucks used to transport spirits for use in wine production will be constructed...

  5. 27 CFR 24.229 - Tank car and tank truck requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Tank car and tank truck... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.229 Tank car and tank truck requirements. Railroad tank cars and tank trucks used to transport spirits for use in wine production will be constructed...

  6. MTF Driven by Plasma Liner Dynamically Formed by the Merging of Plasma Jets: An Overview

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Eskridge, Richard; Martin, Adam; Smith, James; Lee, Michael; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    One approach for standoff delivery of the momentum flux for compressing the target in MTF consists of using a spherical array of plasma jets to form a spherical plasma shell imploding towards the center of a magnetized plasma, a compact toroid (Figure 1). A 3-year experiment (PLX-1) to explore the physics of forming a 2-D plasma liner (shell) by merging plasma jets is described. An overview showing how this 3-year project (PLX-1) fits into the program plan at the national and international level for realizing MTF for energy and propulsion is discussed. Assuming that there will be a parallel program in demonstrating and establishing the underlying physics principles of MTF using whatever liner is appropriate (e.g. a solid liner) with a goal of demonstrating breakeven by 2010, the current research effort at NASA MSFC attempts to complement such a program by addressing the issues of practical embodiment of MTF for propulsion. Successful conclusion of PLX-1 will be followed by a Physics Feasibility Experiment (PLX-2) for the Plasma Liner Driven MTF.

  7. A Requirements-Driven Optimization Method for Acoustic Liners Using Analytic Derivatives

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.; Lopes, Leonard V.

    2017-01-01

    More than ever, there is flexibility and freedom in acoustic liner design. Subject to practical considerations, liner design variables may be manipulated to achieve a target attenuation spectrum. But characteristics of the ideal attenuation spectrum can be difficult to know. Many multidisciplinary system effects govern how engine noise sources contribute to community noise. Given a hardwall fan noise source to be suppressed, and using an analytical certification noise model to compute a community noise measure of merit, the optimal attenuation spectrum can be derived using multidisciplinary systems analysis methods. In a previous paper on this subject, a method deriving the ideal target attenuation spectrum that minimizes noise perceived by observers on the ground was described. A simple code-wrapping approach was used to evaluate a community noise objective function for an external optimizer. Gradients were evaluated using a finite difference formula. The subject of this paper is an application of analytic derivatives that supply precise gradients to an optimization process. Analytic derivatives improve the efficiency and accuracy of gradient-based optimization methods and allow consideration of more design variables. In addition, the benefit of variable impedance liners is explored using a multi-objective optimization.

  8. Reflected wave manipulation by inhomogeneous impedance via varying-depth acoustic liners

    NASA Astrophysics Data System (ADS)

    Guo, Jingwen; Zhang, Xin; Fang, Yi; Fattah, Ryu

    2018-05-01

    Acoustic liners, consisting of a perforated panel affixed to a honeycomb core with a rigid back plate, are widely used for noise attenuation purpose. In this study, by exploiting inhomogeneous impedance properties, we report an experimental and numerical study on a liner-type acoustic metasurface, which possesses the functionality of both reflected wave manipulation and sound energy attenuation simultaneously. To realize the inhomogeneous acoustic impedance, an acoustic metasurface constructed by varying-depth acoustic liners is designed and fabricated. The reflected sound pressure fields induced by the metasurface are obtained in both experiments and simulations. A complete characterization of this metasurface is performed, including the effects of depth gradient, incident angle, and incident frequency. Anomalous reflection, apparent negative reflection, and conversion from an incident wave to a surface wave with strong energy dissipation are achieved by the structure. Moreover, our proposed structure can overcome the single frequency performance limitation that exists in conventional metasurfaces and performs well in a broadband frequency range. The proposed acoustic metasurface offers flexibility in controlling the direction of sound wave propagation with energy dissipation property and holds promise for various applications of noise reduction.

  9. Backside Wear Analysis of Retrieved Acetabular Liners with a Press-Fit Locking Mechanism in Comparison to Wear Simulation In Vitro.

    PubMed

    Puente Reyna, Ana Laura; Jäger, Marcus; Floerkemeier, Thilo; Frecher, Sven; Delank, Karl-Stefan; Schilling, Christoph; Grupp, Thomas M

    2016-01-01

    Backside wear due to micromotion and poor conformity between the liner and its titanium alloy shell may contribute to the high rates of retroacetabular osteolysis and consequent aseptic loosening. The purpose of our study was to understand the wear process on the backside of polyethylene liners from two acetabular cup systems, whose locking mechanism is based on a press-fit cone in combination with a rough titanium conical inner surface on the fixation area. A direct comparison between in vitro wear simulator tests (equivalent to 3 years of use) and retrieved liners (average 13.1 months in situ) was done in order to evaluate the backside wear characteristics and behavior of these systems. Similar wear scores between in vitro tested and retrieved liners were observed. The results showed that this locking mechanism did not significantly produce wear marks at the backside of the polyethylene liners due to micromotion. In all the analyzed liners, the most common wear modes observed were small scratches at the cranial fixation zone directly below the rough titanium inner surface of the shell. It was concluded that most of the wear marks were produced during the insertion and removal of the liner, rather than during its time in situ.

  10. Fusion-neutron measurements for magnetized liner inertial fusion experiments on the Z accelerator

    DOE PAGES

    Hahn, K. D.; Chandler, G. A.; Ruiz, C. L.; ...

    2016-05-26

    Several magnetized liner inertial fusion (MagLIF) experiments have been conducted on the Z accelerator at Sandia National Laboratories since late 2013. Measurements of the primary DD (2.45 MeV) neutrons for these experiments suggest that the neutron production is thermonuclear. Primary DD yields up to 3e12 with ion temperatures ~2-3 keV have been achieved. Measurements of the secondary DT (14 MeV) neutrons indicate that the fuel is significantly magnetized. Measurements of down-scattered neutrons from the beryllium liner suggest ρR liner ~ 1g/cm 2. Neutron bang times, estimated from neutron time-of-flight (nTOF) measurements, coincide with peak x-ray production. Furthermore, plans to improvemore » and expand the Z neutron diagnostic suite include neutron burn-history diagnostics, increased sensitivity and higher precision nTOF detectors, and neutron recoil-based yield and spectral measurements.« less

  11. Fusion-neutron measurements for magnetized liner inertial fusion experiments on the Z accelerator

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

    Hahn, K. D.; Chandler, G. A.; Ruiz, C. L.

    Several magnetized liner inertial fusion (MagLIF) experiments have been conducted on the Z accelerator at Sandia National Laboratories since late 2013. Measurements of the primary DD (2.45 MeV) neutrons for these experiments suggest that the neutron production is thermonuclear. Primary DD yields up to 3e12 with ion temperatures ~2-3 keV have been achieved. Measurements of the secondary DT (14 MeV) neutrons indicate that the fuel is significantly magnetized. Measurements of down-scattered neutrons from the beryllium liner suggest ρR liner ~ 1g/cm 2. Neutron bang times, estimated from neutron time-of-flight (nTOF) measurements, coincide with peak x-ray production. Furthermore, plans to improvemore » and expand the Z neutron diagnostic suite include neutron burn-history diagnostics, increased sensitivity and higher precision nTOF detectors, and neutron recoil-based yield and spectral measurements.« less

  12. Hybrid mode-scattering/sound-absorbing segmented liner system and method

    NASA Technical Reports Server (NTRS)

    Walker, Bruce E. (Inventor); Hersh, Alan S. (Inventor); Rice, Edward J. (Inventor)

    1999-01-01

    A hybrid mode-scattering/sound-absorbing segmented liner system and method in which an initial sound field within a duct is steered or scattered into higher-order modes in a first mode-scattering segment such that it is more readily and effectively absorbed in a second sound-absorbing segment. The mode-scattering segment is preferably a series of active control components positioned along the annulus of the duct, each of which includes a controller and a resonator into which a piezoelectric transducer generates the steering noise. The sound-absorbing segment is positioned acoustically downstream of the mode-scattering segment, and preferably comprises a honeycomb-backed passive acoustic liner. The invention is particularly adapted for use in turbofan engines, both in the inlet and exhaust.

  13. X-ray backlighting of imploding aluminium liners on PTS facility

    NASA Astrophysics Data System (ADS)

    Yang, Qingguo; Liu, Dongbing; Mu, Jian; Huang, Xianbin; Dan, Jiakun; Xie, Xudong; Deng, Wu; Feng, Shuping; Wang, Meng; Ye, Yan; Peng, Qixian; Li, Zeren

    2016-09-01

    The x-ray backlighting systems, including a 1.865 keV (Si Heα line) spherically bent crystal imaging system and an ˜8.3 keV (Cu Heα line) point-projection imaging system, newly fielded on the Primary Test Stand facility are introduced and its preliminary experimental results in radiography of the aluminium (Al) liners with seeded sinusoidal perturbations are presented. The x-ray backlighter source is created using a 1 TW, 1 kJ Nd: glass high power laser, kilo-joule laser system, recently constructed at China Academy of Engineering Physics. The ablation melt and instability of the imploding Al liner outer edge under the driving current of ˜7.5 MA are successfully observed using these two backlighting systems, respectively.

  14. Three Year RSA Evaluation of Vitamin E Diffused Highly Cross-linked Polyethylene Liners and Cup Stability.

    PubMed

    Sillesen, Nanna H; Greene, Meridith E; Nebergall, Audrey K; Nielsen, Poul T; Laursen, Mogens B; Troelsen, Anders; Malchau, Henrik

    2015-07-01

    Vitamin E diffusion into highly cross-linked polyethylene (E-XLPE) is a method for enhancing oxidative stability of acetabular liners. The purpose of this study was to evaluate in vivo penetration of E-XLPE using radiostereometric analysis (RSA). Eighty-four hips were recruited into a prospective 10-year RSA. This is the first evaluation of the multicenter cohort after 3-years. All patients received E-XLPE liners (E1, Biomet) and porous-titanium coated cups (Regenerex, Biomet). There was no difference (P=0.450) in median femoral head penetration into the E-XLPE liners at 3-years comparing cobalt-chrome heads (-0.028mm; inter-quartile range (IQR) - 0.065 to 0.047) with ceramic heads (-0.043mm, IQR - 0.143to0.042). The 3-year follow-up indicates minimal E-XLPE liner penetration regardless of head material and minimal early cup movement. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Numerical and Physical Modeling of the Response of Resonator Liners to Intense Sound and Grazing Flow

    NASA Technical Reports Server (NTRS)

    Hersh, Alan S.; Tam, Christopher

    2009-01-01

    Two significant advances have been made in the application of computational aeroacoustics methodology to acoustic liner technology. The first is that temperature effects for discrete sound are not the same as for broadband noise. For discrete sound, the normalized resistance appears to be insensitive to temperature except at high SPL. However, reactance is lower, significantly lower in absolute value, at high temperature. The second is the numerical investigation the acoustic performance of a liner by direct numerical simulation. Liner impedance is affected by the non-uniformity of the incident sound waves. This identifies the importance of pressure gradient. Preliminary design one and two-dimensional impedance models were developed to design sound absorbing liners in the presence of intense sound and grazing flow. The two-dimensional model offers the potential to empirically determine incident sound pressure face-plate distance from resonator orifices. This represents an important initial step in improving our understanding of how to effectively use the Dean Two-Microphone impedance measurement method.

  16. Acoustic-Liner Admittance in a Duct

    NASA Technical Reports Server (NTRS)

    Watson, W. R.

    1986-01-01

    Method calculates admittance from easily obtainable values. New method for calculating acoustic-liner admittance in rectangular duct with grazing flow based on finite-element discretization of acoustic field and reposing of unknown admittance value as linear eigenvalue problem on admittance value. Problem solved by Gaussian elimination. Unlike existing methods, present method extendable to mean flows with two-dimensional boundary layers as well. In presence of shear, results of method compared well with results of Runge-Kutta integration technique.

  17. Microstructural change in electroformed copper liners of shaped charges upon plastic deformation at ultra-high strain rate

    NASA Astrophysics Data System (ADS)

    Tian, W. H.; Hu, S. L.; Fan, A. L.; Wang, Z.

    2002-01-01

    Transmission electron microscopy (TEM) observations were carried out for examining the as-formed and post-deformed microstructures in a variety of electroformed copper liners of shaped charges. The deformation was carried out at an ultra-high strain rate. Specifically, the electron backscattering Kikuchi pattern (EBSP) technique was utilized to examine the micro-texture of these materials. TEM observations revealed that these electroformed copper liners of shaped charges have a grain size of about 1-3 mum, EBSP analysis demonstrated that the as-grown copper liners of shaped charges exhibit a l 10) fiber micro-texture which is parallel to the normal direction of the surface of the liners of shaped charges. Having undergone plastic deformation at ultra-high strain rate (10(7) s(-1)), the specimens which were recovered from the copper slugs were found to have grain size of the same order as that before deformation. EBSP analysis revealed that the (110) fiber texture existed in the as-formed copper liners disappears in the course of deformation. TEM examination results indicate that dynamic recovery and recrystallization play a significant role in this deformation process.

  18. Aerodynamic design of the contoured wind-tunnel liner for the NASA supercritical, laminar-flow-control, swept-wing experiment

    NASA Technical Reports Server (NTRS)

    Newman, P. A.; Anderson, E. C.; Peterson, J. B., Jr.

    1984-01-01

    An overview is presented of the entire procedure developed for the aerodynamic design of the contoured wind tunnel liner for the NASA supercritical, laminar flow control (LFC), swept wing experiment. This numerical design procedure is based upon the simple idea of streamlining and incorporates several transonic and boundary layer analysis codes. The liner, presently installed in the Langley 8 Foot Transonic Pressure Tunnel, is about 54 ft long and extends from within the existing contraction cone, through the test section, and into the diffuser. LFC model testing has begun and preliminary results indicate that the liner is performing as intended. The liner design results presented in this paper, however, are examples of the calculated requirements and the hardware implementation of them.

  19. Final Report: Research Study on Development of Environmental Friendly Spray-on Foam Insulation (SOFI) for the External Tank (ET)

    NASA Technical Reports Server (NTRS)

    Stuckey, James M.

    1996-01-01

    The selection and quantification of four foams using a more environmentally friendly HCFC-141b blowing agent replacing foams that used the CFC-11 blowing agent for the external tank (ET) LWT has been addressed along with problems and solutions that were encountered during verification. The effort on two lower density spray foams for the ET SLWT are presented, but predicted weight savings were not encouraging. Suggestions for possible problem solving are included along with a new approach for selecting foams for qualification as back-up foams for the foams used on the ET LWT. We investigated three resins for use as thermally sprayed coatings for corrosion prevention on metal. The best coating was obtained with a thermoplastic polyimide resin. This coating has a good chance of meeting ET requirements. Possible third generation blowing agents have been shown usable in polyurethane spray and pour foams, and solubility in isocyannate foam components are acceptable. We considered aerogels as insulation materials on space vehicles, and suggested a liner for a liquid oxygen (LOX) composite tank.

  20. Matching an Inductive Accumulator and a System of Acceleration of a Liner with Limitation of the Breaking Voltage,

    DTIC Science & Technology

    In this work calculations are made of the efficiencies of acceleration of a liner from an inductive accumulator in the mode theta-pinch and Z-pinch...to the speed of the liner . Estimations have been made of the necessary power at the moment of switching the current on the basis of considerations of...the stability of the pinch effect of the liner . The level of energies necessary for the creation of a thermonuclear reactor on the basis of theta

  1. 49 CFR 180.519 - Periodic retest and inspection of tank cars other than single-unit tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Periodic retest and inspection of tank cars other than single-unit tank car tanks. 180.519 Section 180.519 Transportation Other Regulations Relating to... of Tank Cars § 180.519 Periodic retest and inspection of tank cars other than single-unit tank car...

  2. 3D printed liner for treatment of periprosthetic joint infections.

    PubMed

    Kim, Tae Won B; Lopez, Osvaldo J; Sharkey, Jillian P; Marden, Kyle R; Murshed, Muhammad Ridwan; Ranganathan, Shivakumar I

    2017-05-01

    In the United States, long standing deep infections of joint arthroplasty, such as total knee and total hip replacements, are treated with two-stage exchange. This requires the removal of the prior implant, placement of an antibiotic eluting spacer block made of polymethylmethacrylate (PMMA), followed by re-implantation of a new implant after treatment with intravenous antibiotics for six to eight weeks. Unfortunately, the use of PMMA as a spacer material has limitations in terms of mechanical and drug-eluting properties. PMMA is brittle and elutes most of the antibiotics within the first few days. Furthermore, the polymerization reaction for PMMA is highly exothermic, thereby limiting the use to heat-stable antibiotics. We hypothesize that the use of a 3D printed polymeric liner made of polylactic acid (PLA) would overcome the limitations of PMMA because it is a stronger and a less brittle material than PMMA. Furthermore, the liner can also act as a controlled drug delivery vehicle by using built in reservoirs and a network of micro-channels as well as by incorporating antibiotics directly into the polymer during manufacturing stage. Finally, the liner can be 3D printed according to the anatomy of the patient and thereby has the potential to transform the manner in which periprosthetic joint infections are currently treated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Increasing the endurance of electrodes of heating salt tanks

    NASA Astrophysics Data System (ADS)

    Kulikov, A. I.

    1997-05-01

    Electrodes used for heating, melting, and sustaining the requisite temperature regime in salt tanks for heat treatment of metals and alloys operate under severe conditions (heating to 1300°C, aggressive medium of the melts of salts of alkali and alkali-earth metals). This causes early failure of the electrodes, and the heat treatment unit is stopped for repair. For example, the design service life of electrodes for SVS 2.3/13I tanks is two months, but as a rule it does not exceed one month of continuous operation. The replacement of conventional low-carbon electrode steel (for example, of grade 10) by a more expensive heat- and corrosion-resistant steel has not proved effective but rather increased the cost of the electrodes and hence the cost of the produced parts. In this connection, it is interesting to get acquainted with works devoted to increasing the service life of salt-tank electrodes for heat treatment shops of machine-building and tool plants. The present paper describes such an attempt.

  4. Vibration Considerations for Cryogenic Tanks Using Glass Bubbles Insulation

    NASA Technical Reports Server (NTRS)

    Werlink, Rudolph J.; Fesmire, James E.; Sass, Jared P.

    2011-01-01

    The use of glass bubbles as an efficient and practical thermal insulation system has been previously demonstrated in cryogenic storage tanks. One such example is a spherical, vacuum-jacketed liquid hydrogen vessel of 218,000 liter capacity where the boiloff rate has been reduced by approximately 50 percent. Further applications may include non-stationary tanks such as mobile tankers and tanks with extreme duty cycles or exposed to significant vibration environments. Space rocket launch events and mobile tanker life cycles represent two harsh cases of mechanical vibration exposure. A number of bulk fill insulation materials including glass bubbles, perlite powders, and aerogel granules were tested for vibration effects and mechanical behavior using a custom design holding fixture subjected to random vibration on an Electrodynamic Shaker. The settling effects for mixtures of insulation materials were also investigated. The vibration test results and granular particle analysis are presented with considerations and implications for future cryogenic tank applications. A thermal performance update on field demonstration testing of a 218,000 L liquid hydrogen storage tank, retrofitted with glass bubbles, is presented. KEYWORDS: Glass bubble, perlite, aerogel, insulation, liquid hydrogen, storage tank, mobile tanker, vibration.

  5. Attenuation of FJ44 Turbofan Engine Noise with a Foam-Metal Liner Installed Over-the-Rotor

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Elliott, Dave M.; Jones, Michael G.; Hartley, Thomas C.

    2009-01-01

    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was used as a demonstrator for a Foam-Metal Liner (FML) installed in close proximity to the fan. Two FML designs were tested and compared to the hardwall baseline. Traditional single degree-of-freedom liner designs were also evaluated to provide a comparison. Farfield acoustic levels and limited engine performance results are presented in this paper. The results show that the FML achieved up to 5 dB Acoustic Power Level (PWL) overall attenuation in the forward quadrant, equivalent to the traditional liner design. An earlier report presented the test set-up and conditions.

  6. Evolution of helical perturbations in a thin-shell model of an imploding liner

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

    Ryutov, D. D.; Dorf, M. A.

    A thin-shell model of the liner stability has been revisited and applied to the stability of the helical perturbations. Several stages of the implosion have been identified, starting from a long initial “latent” phase of an almost resting liner, continuing to the second stage of a rapid contraction and significant perturbation growth, and then transitioning to the third stage where perturbations become ballistic and highly non-linear. The stage of stagnation and rebound is beyond the scope of this paper. An importance of vorticity conservation during the late stages is emphasized. Nonlinear evolution of perturbations is followed up to the pointmore » of the formation of cusp structures. Effects of in-surface flows and of their enhancement due to the vorticity conservation are discussed. It is shown that the pre-machined perturbations created only on the outer surface of the liner grow much slower than one could anticipate. The limitations on the thin-shell description are discussed.« less

  7. Evaluate the Effect of Commercially Available Denture Cleansers on Surface Hardness and Roughness of Denture Liners at Various Time Intervals

    PubMed Central

    Mohammed, Hilal S.; Singh, Sumeet; Hari, Prasad A.; Amarnath, G. S.; Kundapur, Vinaya; Pasha, Naveed; Anand, M.

    2016-01-01

    Background and objective: Chemical cleansing by denture cleansers is first choice for denture plaque control. The most common problems while using denture cleansers are hardening, porosity, odor sorption, water sorption, solubility, and colour change, bacterial and fungal growth. Chemical cleansing procedures have been found to have an effect on the physical and mechanical properties of denture liners. Thus, this study was conducted to evaluate the effect of commercially available denture cleansers on surface hardness and roughness of acrylic and silicon based denture liners at various time interval. Method: Two autopolymerising denture liners Kooliner (acrylic) and GC reline soft (silicon) were tested with two commercially available denture cleansers, polident and efferdent plus. Total of 120 specimens were prepared and all the specimens were divided into six groups based on the relining materials and denture cleansers used. Surface hardness and surface roughness was tested using Shore A durometer and profilometer respectively at the end of day 1, day 7, day 30 and day 90. All the specimens were stored in artificial saliva throughout the study. Cleanser solution was prepared daily by adding Polident and Efferdent plus denture cleanser tablet into 250ml of enough very warm (not hot) water. Acrylic and silicon liner groups were cleansed in a solution of denture cleanser and water for 15 minutes daily, rinsed with water and stored in artificial saliva at room temperature. The data was analyzed with one way ANOVA and independent t-test. Result: The acrylic soft lining showed gradual hardening and increase in surface roughness after immersion in denture cleanser and also with time. Acrylic liner material showed maximum hardness and roughness with Polident followed by Efferdent plus and water (control group). Silicone lining material showed a slight difference in hardness and roughness between the test group and control group. There was a slight increase in hardness in

  8. Evaluation of multidimensional transport through a field-scale compacted soil liner

    USGS Publications Warehouse

    Willingham, T.W.; Werth, C.J.; Valocchi, A.J.; Krapac, I.G.; Toupiol, C.; Stark, T.D.; Daniel, D.E.

    2004-01-01

    A field-scale compacted soil liner was constructed at the University of Illinois at Urbana-Champaign by the U.S. Environmental Protection Agency (USEPA) and Illinois State Geological Survey in 1988 to investigate chemical transport rates through low permeability compacted clay liners (CCLs). Four tracers (bromide and three benzoic acid tracers) were each added to one of four large ring infiltrometers (LRIs) while tritium was added to the pond water (excluding the infiltrometers). Results from the long-term transport of Br- from the localized source zone of LRI are presented in this paper. Core samples were taken radially outward from the center of the Br- LRI and concentration depth profiles were obtained. Transport properties were evaluated using an axially symmetric transport model. Results indicate that (1) transport was diffusion controlled; (2) transport due to advection was negligible and well within the regulatory limits of ksat???1 ?? 10-7 cm/s; (3) diffusion rates in the horizontal and vertical directions were the same; and (4) small positioning errors due to compression during soil sampling did not affect the best fit advection and diffusion values. The best-fit diffusion coefficient for bromide was equal to the molecular diffusion coefficient multiplied by a tortuosity factor of 0.27, which is within 8% of the tortuosity factor (0.25) found in a related study where tritium transport through the same liner was evaluated. This suggests that the governing mechanisms for the transport of tritium and bromide through the CCL were similar. These results are significant because they address transport through a composite liner from a localized source zone which occurs when defects or punctures in the geomembrane of a composite system are present. ?? ASCE.

  9. The influence of head diameter and wall thickness on deformations of metallic acetabular press-fit cups and UHMWPE liners: a finite element analysis.

    PubMed

    Goebel, Paul; Kluess, Daniel; Wieding, Jan; Souffrant, Robert; Heyer, Horst; Sander, Manuela; Bader, Rainer

    2013-03-01

    To increase the range of motion of total hip endoprostheses, prosthetic heads need to be enlarged, which implies that the cup and/or liner thickness must decrease. This may have negative effects on the wear rate, because the acetabular cups and liners could deform during press-fit implantation and hip joint loading. We compared the metal cup and polyethylene liner deformations that occurred when different wall thicknesses were used in order to evaluate the resulting changes in the clearance of the articulating region. A parametric finite element model utilized three cup and liner wall thicknesses to analyze cup and liner deformations after press-fit implantation into the pelvic bone. The resultant hip joint force during heel strike was applied while the femur was fixed, accounting for physiological muscle forces. The deformation behavior of the liner under joint loading was therefore assessed as a function of the head diameter and the resulting clearance. Press-fit implantation showed diametral cup deformations of 0.096, 0.034, and 0.014 mm for cup wall thicknesses of 3, 5, and 7 mm, respectively. The largest deformations (average 0.084 ± 0.003 mm) of liners with thicknesses of 4, 6, and 8 mm occurred with the smallest cup wall thickness (3 mm). The smallest liner deformation (0.011 mm) was obtained with largest cup and liner wall thicknesses. Under joint loading, liner deformations in thin-walled acetabular cups (3 mm) reduced the initial clearance by about 50 %. Acetabular press-fit cups with wall thicknesses of ≤5 mm should only be used in combination with polyethylene liners >6 mm thick in order to minimize the reduction in clearance.

  10. Ram-pressure scaling and non-uniformity characterization of a spherically imploding liner formed by hypervelocity plasma jets

    NASA Astrophysics Data System (ADS)

    Cassibry, Jason; Dougherty, Jesse; Thompson, Seth; Hsu, Scott; Witherspoon, F. D.; University of AL in Huntsville Team; Los Alamos National Laboratory Team; HyperV Technologies Corp. Team

    2014-10-01

    Three-dimensional modeling of plasma liner formation and implosion is performed using the Smoothed Particle Hydrodynamics Code (SPHC) with radiation, thermal transport, and tabular equations of state (EOS), accounting for ionization, in support of a proposed 60-gun plasma liner formation experiment for plasma-jet driven magneto-inertial fusion (PJMIF). Previous SPHC modeling showed that ideal gas law scaling of peak stagnation pressure increased linearly with density and number of jets, quadratically with jet radius and velocity, and inversely with the initial jet length, while results with tabular EOS, thermal transport, and radiation have greater sensitivity to the initial jet distribution. A series of simulations are conducted to study the effects of initial jet conditions on peak ram pressure and liner non-uniformity during plasma liner implosion. The growth rate of large-amplitude density perturbations introduced by the discrete jets are computed and compared with predictions by the Bell-Plesset equation.

  11. Effect of low-stiffness closeout overwrap on rocket thrust-chamber life

    NASA Technical Reports Server (NTRS)

    Kasper, H. J.; Nota-Donato, J. J.

    1979-01-01

    Three rocket thrust chambers with copper liners and a thrust level of 20.9 kN were cyclically test fired to failure. Two of the liners were made from oxygen free, high conductivity (OFHC) copper and from annealed Amzirc. The milled coolant channels were closed out with a thin copper closeout over which a fiberglass composite was wrapped to provide hoop strength only. Experimental data are presented, along with the results of a preliminary analysis that was performed before fabrication to evaluate the life extending potential of a thin copper closeout with a fiberglass overwrap.

  12. Energy storage-boiler tank

    NASA Astrophysics Data System (ADS)

    Chubb, T. A.; Nemecek, J. J.; Simmons, D. E.

    1980-03-01

    Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed.

  13. Energy storage-boiler tank

    NASA Technical Reports Server (NTRS)

    Chubb, T. A.; Nemecek, J. J.; Simmons, D. E.

    1980-01-01

    Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed.

  14. Electric Plasma Arc-Lamp Combustor Liner Durability Test System Developed

    NASA Technical Reports Server (NTRS)

    Goldsby, Jon C.; Halbig, Michael C.

    2000-01-01

    Silicon carbide matrix composites are candidate materials for high-temperature combustor liners. Because through-the-thickness thermal gradients are the primary cause of stress on combustor liners, a unique test facility was developed at the NASA Glenn Research Center at Lewis Field to simulate in-service pure thermal stress distributions in fiber reinforced silicon carbide cylinders. It was developed initially under Phase II of the High- Speed Research Program. This test stand can accommodate 8-in.-long test cylinders that have outer diameters of 4 in. and a wall thickness of about 0.08 to 0.12 in. One cylinder at a time is loaded vertically into the test stand. Water-cooled plates enclose the open ends of the cylinder and provide cooling. Load plates on the exterior side of the water-cooled plates provide support and compression loads. To evaluate a combustor liner material s potential performance, researchers induce thermal gradients with an axisymmetric, direct-current, electric arc within the cylinder while refrigerated air at a rate of 1.5 lb/sec impinges on the outside surface of the cylinder. The achievable through-the-thickness thermal gradient is predicted to be in excess of 200 C. The 8-in. long, 0.5-in.-diameter plasma arc emits full spectrum visible light; radiant intensity exceeds 300 Watts per square centimeters to produce temperatures in excess of 1500 C on materials with emissivity near unity. Because the system does not rely upon the combustion of fuels to achieve the related thermal conditions, ancillary environmental reactions with the sample are eliminated. The system incorporates a standard mechanical test frame, which can impose constant as well cyclical axial stresses up to 2200 lb upon the test piece. Silicon-carbide-fiber reinforced silicon carbide matrix composite cylinders were instrumented with thin-film thermocouples to obtain through-the-thickness thermal flux measurements. Inside wall temperatures reached 1200 C with only 250 A of

  15. Development of variable-rate sprayer for nursery liner applications

    USDA-ARS?s Scientific Manuscript database

    Sensor-guided application technologies are needed to achieve constant spray deposition for the rapid growth of nursery liner trees during a growing season. An experimental real-time variable-rate sprayer that implemented 20 Hz ultrasonic sensors and pulse width modulation (PWM) solenoid valve-contro...

  16. Dual Tank Fuel System

    DOEpatents

    Wagner, Richard William; Burkhard, James Frank; Dauer, Kenneth John

    1999-11-16

    A dual tank fuel system has primary and secondary fuel tanks, with the primary tank including a filler pipe to receive fuel and a discharge line to deliver fuel to an engine, and with a balance pipe interconnecting the primary tank and the secondary tank. The balance pipe opens close to the bottom of each tank to direct fuel from the primary tank to the secondary tank as the primary tank is filled, and to direct fuel from the secondary tank to the primary tank as fuel is discharged from the primary tank through the discharge line. A vent line has branches connected to each tank to direct fuel vapor from the tanks as the tanks are filled, and to admit air to the tanks as fuel is delivered to the engine.

  17. AN EVALUATION OF POTENTIAL LINER MATERIALS FOR ELIMINATING FCCI IN IRRADIATED METALLIC NUCLEAR FUEL ELEMENTS

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

    D. D. Keiser; J. I. Cole

    2007-09-01

    Metallic nuclear fuels are being looked at as part of the Global Nuclear Energy Program for transmuting longlive transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products. In order to optimize the performance of these fuels, the concept of using liners to eliminate the fuel/cladding chemical interactions that can occur during irradiation of a fuel element has been investigated. The potential liner materials Zr and V have been tested using solid-solid diffusion couples, consisting of liner materials butted against fuel alloys and against cladding materials. The couples were annealed at the relatively high temperature of 700°C. Thismore » temperature would be the absolute maximum temperature present at the fuel/cladding interface for a fuel element in-reactor. Analysis was performed using a scanning electron microscope equipped with energy-dispersive and wavelengthdispersive spectrometers (SEM/EDS/WDS) to evaluate any developed diffusion structures. At 700°C, minimal interaction was observed between the metallic fuels and either Zr or V. Similarly, limited interaction was observed between the Zr and V and the cladding materials. The best performing liner material appeared to be the V, based on amounts of interaction.« less

  18. Spin-rolling, welding, and heat treatment of aluminium 2219 for Ariane 5 GAM high pressure vessel liners

    NASA Astrophysics Data System (ADS)

    Radtke, W.

    1992-10-01

    Cylindrical liners made of Al 2219 may be spinrolled if both recrystallization and metastable precipitates can be avoided during forging or preparatory heat treatment. So welding is to be limited to circumferential joints. Pore-free welds are attainable immediately after hydroxide layer removal by diamond cutting without grease application. The EB vacuum is favorable to porosity suppression. A complete heat treatment of the liner incorporating solutionizing, water quenching and ageing leads to 100 percent weld efficiency. Pressure stabilization avoids buckling. Subsequent carbon fiber winding, curing and plastic prestressing of the liner results in an efficient high pressure vessel for hydrogen service.

  19. Modelling the impact of liner shipping network perturbations on container cargo routing: Southeast Asia to Europe application.

    PubMed

    Achurra-Gonzalez, Pablo E; Novati, Matteo; Foulser-Piggott, Roxane; Graham, Daniel J; Bowman, Gary; Bell, Michael G H; Angeloudis, Panagiotis

    2016-06-03

    Understanding how container routing stands to be impacted by different scenarios of liner shipping network perturbations such as natural disasters or new major infrastructure developments is of key importance for decision-making in the liner shipping industry. The variety of actors and processes within modern supply chains and the complexity of their relationships have previously led to the development of simulation-based models, whose application has been largely compromised by their dependency on extensive and often confidential sets of data. This study proposes the application of optimisation techniques less dependent on complex data sets in order to develop a quantitative framework to assess the impacts of disruptive events on liner shipping networks. We provide a categorization of liner network perturbations, differentiating between systemic and external and formulate a container assignment model that minimises routing costs extending previous implementations to allow feasible solutions when routing capacity is reduced below transport demand. We develop a base case network for the Southeast Asia to Europe liner shipping trade and review of accidents related to port disruptions for two scenarios of seismic and political conflict hazards. Numerical results identify alternative routing paths and costs in the aftermath of port disruptions scenarios and suggest higher vulnerability of intra-regional connectivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Approaches to consider covers and liners in a low-level waste disposal facility performance assessment

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

    Seitz, Roger; Phifer, Mark; Suttora, Linda

    2015-03-17

    On-site disposal cells are in use and being considered at several USDOE sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These disposal cells are typically regulated by States and/or the USEPA in addition to having to comply with requirements in DOE Order 435.1, Radioactive Waste Management. The USDOE-EM Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) disposal cells and work towards more consistent assumptions, as appropriate, for technical andmore » policy considerations related to performance and risk assessments in support of a Record of Decision and Disposal Authorization Statement. One task completed by the working group addressed approaches for considering the performance of covers and liners/leachate collection systems in the context of a performance assessment (PA). A document has been prepared which provides recommendations for a general approach to address covers and liners/leachate collection systems in a PA and how to integrate assessments with defense-in-depth considerations such as design, operations and waste acceptance criteria to address uncertainties. Specific information and references are provided for details needed to address the evolution of individual components of cover and liner/leachate collection systems. This information is then synthesized into recommendations for best practices for cover and liner system design and examples of approaches to address the performance of covers and liners as part of a performance assessment of the disposal system.« less

  1. Durability, Performance, and Emission of Diesel Engines Using Carbon Fiber Piston and Liner

    NASA Technical Reports Server (NTRS)

    Afify, E. M.; Roberts, W. L.

    1999-01-01

    This report summarizes the research conducted by NC State University in investigating the durability, performance and emission of a carbon fiber piston and liner in our single cylinder research Diesel engine. Both the piston and liner were supplied to NC State University by NASA LaRC and manufactured by C-CAT under a separate contract to NASA LaRC. The carbon-carbon material used to manufacture the piston and liner has significantly lower thermal conductivity, coefficient of thermal expansion, and superior strength characteristics at elevated temperatures when compared to conventional piston materials such as aluminum. The results of the carbon-carbon fiber piston testing were compared to a baseline configuration, which used a conventional aluminum piston in a steel liner. The parameters measured were the brake specific fuel consumption, ignition delay, frictional horsepower, volumetric efficiency, and durability characteristics of the two pistons. Testing was performed using a naturally aspirated Labeco Direct Injection single cylinder diesel engine. Two test cases were performed over a range of loads and speeds. The fixed test condition between the aluminum and carbon-carbon piston configurations was the brake mean effective pressure. The measured data was the fuel consumption rate, volumetric efficiency, load, speed, cylinder pressure, needle lift, and exhaust gas temperature. The cylinder pressure, and fuel consumption, exhaust gas temperature, and needle lift were recorded using a National Instruments DAQ board and a PC. All test cases used Diesel no. 2 for fuel.

  2. One-dimensional radiation-hydrodynamic simulations of imploding spherical plasma liners with detailed equation-of-state modeling

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

    Davis, J. S.; Hsu, S. C.; Golovkin, I. E.

    2012-10-15

    This work extends the one-dimensional radiation-hydrodynamic imploding spherical argon plasma liner simulations of Awe et al.[Phys. Plasmas 18, 072705 (2011)] by using a detailed tabular equation-of-state (EOS) model, whereas Awe et al. used a polytropic EOS model. Results using the tabular EOS model give lower stagnation pressures by a factor of 3.9-8.6 and lower peak ion temperatures compared to the polytropic EOS results. Both local thermodynamic equilibrium (LTE) and non-LTE EOS models were used in this work, giving similar results on stagnation pressure. The lower stagnation pressures using a tabular EOS model are attributed to a reduction in the liner'smore » ability to compress arising from the energy sink introduced by ionization and electron excitation, which are not accounted for in a polytropic EOS model. Variation of the plasma liner species for the same initial liner geometry, mass density, and velocity was also explored using the LTE tabular EOS model, showing that the highest stagnation pressure is achieved with the highest atomic mass species for the constraints imposed.« less

  3. IET. Stack interior. Masons lay fire brick liner, leaving air ...

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

    IET. Stack interior. Masons lay fire brick liner, leaving air layer between bricks and concrete wall. Date: May 20, 1955. INEEL negative no. 55-1306 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  4. SLIDE PRESENTATION: LIMITATIONS OF USE OF GEOSYNTHETIC CLAY LINERS (GCLS)

    EPA Science Inventory

    This presentation describes the design and construction issues pertaining to the use of geosynthetic clay liners (GCLSs) in waste containment. The presentation covers new materials, potential design and construction pitfalls and a summary of ongoing research.

  5. Oxide ceramic femoral heads contribute to the oxidation of polyethylene liners in artificial hip joints.

    PubMed

    Pezzotti, Giuseppe; Zhu, Wenliang; Sugano, Nobuhiko; Marin, Elia; Yamamoto, Kengo; Nishiike, Naomichi; Hori, Tsubasa; Rondinella, Alfredo; McEntire, Bryan J; Bock, Ryan; Sonny Bal, B

    2018-06-01

    Experimental evidence demonstrates that a loss of stoichiometry at the surface of oxide bioceramic femoral heads enhances the oxidation rate of polyethylene acetabular liners in artificial hip joints. Contradicting the common notion that ceramics are bioinert, three independent experiments confirmed substantial chemical interactions between the ceramic femoral heads and their polyethylene counterparts. The experiments reported herein included hydrothermal tests, frictional tests, and hip-simulator experiments. It was discovered that oxide and non-oxide femoral heads differently affected the oxidation processes at the surface of the polyethylene liners, all other testing parameters being equal. Analytical data from X-ray photoelectron (XPS), cathodoluminescence (CL), Fourier-transform infrared (FTIR), and Raman spectroscopies unequivocally and consistently showed that the oxidation rate of polyethylene liners was greater when coupled with oxide as opposed to non-oxide ceramic heads. XPS analyses of O-Al-O bond fractions at the surface of a zirconia-toughened alumina (ZTA) short-term (20 months in vivo) femoral heads retrieval showed a ~50% reduction in favor of oxygen vacancy O-Al-V O and hydroxylated Al-O-H bonds. Off-stoichiometry drifts were confirmed in vitro under both static and dynamic conditions. They triggered oxidation and tangibly affected an advanced highly cross-linked sequentially irradiated and annealed ultra-high molecular weight polyethylene (UHMWPE) liner (increase in oxidation index up to ΔOI~1.2 after 5 × 10 5 cycles under dynamic swing conditions). Second-generation UHMWPE liners infused with vitamin E were also affected by the free flow of oxygen from the oxide femoral heads, although to a lesser extent. The fundamental findings of this study, which were also confirmed on retrievals, call for revised standards in material design and testing. Adopting these new criteria will provide an improved understanding of the importance of off

  6. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... tank. (2) A new vessel of 70,000 tons DWT or more must have at least two slop tanks. (b) Capacity. Slop tanks must have the total capacity to retain oily mixtures from cargo tank washings, oil residue, and ballast water containing an oily mixture of 3 percent or more of the oil carrying capacity. Two percent...

  7. Review and Evaluation of Analyses on the Economic Impact of Rate and Service Cooperation by Ocean Liner Companies

    DOT National Transportation Integrated Search

    1984-03-01

    The literature on liner shipping companies is reviewed and discussed. The first section of the report examines the argument that liner shipping has unique characteristics that require a special public policy as regards monopoly and anti-trust legisla...

  8. Analysis of Potential for Titanium Liner Buckling after Proof in a Large Kevlar/Epoxy COPV

    NASA Technical Reports Server (NTRS)

    Phoenix, S. Leigh; Kezirian, Michael T.

    2009-01-01

    We analyze the potential for liner buckling in a 40-in Kevlar49/epoxy overwrapped spherical pressure vessel (COPV) due to long, local depressions or valleys in the titanium liner, which appeared after proof testing (autofrettage). We begin by presenting the geometric characteristics of approximately 20 mil (0.02 in.) deep depressions measured by laser profilometry in several vessels. While such depths were more typical, depths of more than 40 mils (0.02 in.) were seen near the equator in one particular vessel. Such depressions are largely the result of overlap of the edges of overwrap bands (with rectangular cross-section prepreg tows) from the first or second wrap patterns particularly where they start and end. We then discuss the physical mechanisms of formation of the depressions during the autofrettage process in terms of uneven void compaction in the overwrap around the tow overlap lines and the resulting 10-fold increase in through-thickness stiffness of the overwrap. We consider the effects of liner plastic yielding mechanisms in the liner on residual bending moments and interface pressures with the overwrap both at the peak proof pressure (approx.6500 psi) and when reducing the pressure to 0 psi. During depressurization the Bauschinger phenomenon becomes very important whereby extensive yielding in tension reduces the magnitude of the yield threshold in compression by 30 to 40%, compared to the virgin annealed state of the liner titanium. In the absence of a depression, the liner is elastically stable in compression even at liner overwrap interface pressures nominally 6 times the approx. 1000 psi interface pressure that exists at 0 psi. Using a model based on a plate-on-an-elastic-foundation, we develop an extensive analysis of the possible destabilizing effects of a frozen-in valley. The analysis treats the modifying effects of the residual bending moments and interface pressures remaining after the proof hold as well as the Bauschinger effect on the

  9. Influence of the mechanical properties of resilient denture liners on the retention of overdenture attachments.

    PubMed

    Kubo, Keitaro; Koike, Takashi; Ueda, Takayuki; Sakurai, Kaoru

    2018-03-15

    Information is lacking about the selection criteria for silicone resilient denture liners applied as a matrix material for attachments on overdentures. The purpose of this in vitro study was to investigate the mechanical properties of silicone resilient denture liners and their influence on the initial retention force of overdenture attachments and the reduction in retention force over time. Nine types of silicone resilient denture liner were injected and fixed to the matrix section of an experimental denture base. They were then fitted to an epoxy resin model that simulated the residual ridge with a patrix ball attachment (n=10). The retention force of the denture was measured with a digital force gauge, and the maximum force of traction (N) was regarded as the initial retention force. The retention force reduction (N) after repeated insertion and removal (n=5) was calculated by subtracting the retention force after 3348 cycles (3-year simulated insertion and removal) from the initial retention force. The intaglio of the matrix was observed with a scanning electron microscope (SEM) before and after the 3348 cycles. Four mechanical properties (hardness, strain-in-compression, tensile strength, and arithmetic mean roughness) of the resilient denture liners were measured. One-way ANOVA of the initial retention force of each lining material was performed, followed by the Scheffe test (α=.05). Pearson correlation analysis was used (α=.05) to analyze correlations of the initial retention force with the retention force reduction after insertion and removal and the mechanical properties of each material. Multiple regression analysis with the stepwise method extracted the initial retention force and the retention force reduction as dependent variables, and the resilient denture liner mechanical properties as explanatory variables (α=.05). The initial retention force of the resilient denture liners was 1.3 to 5.4 N. Multiple comparisons showed significant differences in

  10. Tank System Integrated Model: A Cryogenic Tank Performance Prediction Program

    NASA Technical Reports Server (NTRS)

    Bolshinskiy, L. G.; Hedayat, A.; Hastings, L. J.; Sutherlin, S. G.; Schnell, A. R.; Moder, J. P.

    2017-01-01

    Accurate predictions of the thermodynamic state of the cryogenic propellants, pressurization rate, and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning for future space exploration missions. This Technical Memorandum (TM) presents the analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, mixing, and condensation on the tank wall. This TM also includes comparisons of TankSIM program predictions with the test data andexamples of multiphase mission calculations.

  11. Injector design for liner-on-target gas-puff experiments

    NASA Astrophysics Data System (ADS)

    Valenzuela, J. C.; Krasheninnikov, I.; Conti, F.; Wessel, F.; Fadeev, V.; Narkis, J.; Ross, M. P.; Rahman, H. U.; Ruskov, E.; Beg, F. N.

    2017-11-01

    We present the design of a gas-puff injector for liner-on-target experiments. The injector is composed of an annular high atomic number (e.g., Ar and Kr) gas and an on-axis plasma gun that delivers an ionized deuterium target. The annular supersonic nozzle injector has been studied using Computational Fluid Dynamics (CFD) simulations to produce a highly collimated (M > 5), ˜1 cm radius gas profile that satisfies the theoretical requirement for best performance on ˜1-MA current generators. The CFD simulations allowed us to study output density profiles as a function of the nozzle shape, gas pressure, and gas composition. We have performed line-integrated density measurements using a continuous wave (CW) He-Ne laser to characterize the liner gas density. The measurements agree well with the CFD values. We have used a simple snowplow model to study the plasma sheath acceleration in a coaxial plasma gun to help us properly design the target injector.

  12. Injector design for liner-on-target gas-puff experiments.

    PubMed

    Valenzuela, J C; Krasheninnikov, I; Conti, F; Wessel, F; Fadeev, V; Narkis, J; Ross, M P; Rahman, H U; Ruskov, E; Beg, F N

    2017-11-01

    We present the design of a gas-puff injector for liner-on-target experiments. The injector is composed of an annular high atomic number (e.g., Ar and Kr) gas and an on-axis plasma gun that delivers an ionized deuterium target. The annular supersonic nozzle injector has been studied using Computational Fluid Dynamics (CFD) simulations to produce a highly collimated (M > 5), ∼1 cm radius gas profile that satisfies the theoretical requirement for best performance on ∼1-MA current generators. The CFD simulations allowed us to study output density profiles as a function of the nozzle shape, gas pressure, and gas composition. We have performed line-integrated density measurements using a continuous wave (CW) He-Ne laser to characterize the liner gas density. The measurements agree well with the CFD values. We have used a simple snowplow model to study the plasma sheath acceleration in a coaxial plasma gun to help us properly design the target injector.

  13. Ageing of structural materials in tokamaks: TEXTOR liner study

    NASA Astrophysics Data System (ADS)

    Weckmann, A.; Petersson, P.; Rubel, M.; Fortuna-Zaleśna, E.; Zielinski, W.; Romelczyk-Baishya, B.; Grigore, E.; Ruset, C.; Kreter, A.

    2017-12-01

    After the final shut-down of the tokamak TEXTOR, all of its machine parts became accessible for comprehensive studies. This unique opportunity enabled the study of the Inconel 625 liner by a wide range of methods. The aim was to evaluate eventual alteration of surface and bulk characteristics from recessed wall elements that may influence the machine performance. The surface was covered with stratified layers consisting mainly of boron, carbon, oxygen, and in some cases also silicon. Wall conditioning and limiter materials hence predominantly define deposition on the liner. Deposited layers on recessed wall elements reach micrometre thickness within decades, peel off and may contribute to the dust inventory in tokamaks. Deuterium content was about 4,7 at% on average most probably due to wall conditioning with deuterated gas, and very low concentration in the Inconel substrate. Inconel 625 retained its mechanical strength despite 26 years of cyclic heating, stresses and particle bombardment.

  14. Wear of a 5 megarad cross-linked polyethylene liner: a 6-year RSA study.

    PubMed

    Callary, Stuart A; Campbell, David G; Mercer, Graham; Nilsson, Kjell G; Field, John R

    2013-07-01

    One cross-linked polyethylene (XLPE) liner is manufactured using a lower dose of radiation, 5 Mrad, which may result in less cross-linking. The reported in vivo wear rate of this XLPE liner in patients undergoing THA has varied, and has included some patients in each reported cohort who had greater than 0.1 mm/year of wear, which is an historical threshold for osteolysis. Previous studies have measured wear on plain radiographs, an approach that has limited sensitivity. We therefore measured the amount and direction of wear at 6 years using Radiostereometric analysis (RSA) in patients who had THAs that included a cross-linked polyethylene liner manufactured using 5 Mrad radiation. We prospectively reviewed wear in 30 patients who underwent primary THAs with the same design of cross-linked acetabular liner and a 28-mm articulation. Tantalum markers were inserted during surgery and all patients had RSA radiographic examinations at 1 week, 6 months, 1, 2, and 6 years postoperatively. The mean proximal, two-dimensional (2-D) and three-dimensional (3-D) wear rates calculated between 1 year and 6 years were 0.014, 0.014, and 0.018 mm/per year, respectively. The direction of the head penetration recorded between 1 week and 6 years was in a proximal direction for all patients, proximolateral for 16 of 24 patients, and proximomedial for eight of 24 patients. The proximal, 2-D and 3-D wear of a XLPE liner produced using 5 Mrad of radiation was low but measurable by RSA after 6 years. No patients had proximal 2-D or 3-D wear rates exceeding 0.1 mm/year. Further followup is needed to evaluate the effect of XLPE wear particles on the development of long-term osteolysis.

  15. Collaboration with Williams International to Demonstrate the Characteristics of a Foam-Metal-Liner Installed Over-the-Rotor of a Turbofan Engine

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel; Elliott, Dave; Jones, Mike; Hartley, Tom

    2008-01-01

    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was used as a demonstrator for foam-metal liner installed in close proximity to the fan. Two foam metal liner designs were tested and compared to the hardwall. Traditional Single-Degree-of-Freedom liner designs were also evaluated to provide a comparison. Normalized information on farfield acoustics is presented in this paper. The results show that up to 5 dB PWL overall attenuation was achieved in the forward quadrant. In general, the foam-metal liners performed better when the fan tip speed was below sonic.

  16. Ultraviolet spectrophotometry of three LINERs

    NASA Technical Reports Server (NTRS)

    Goodrich, R. W.; Keel, W. C.

    1986-01-01

    Three galaxies known to be LINERs were observed spectroscopically in the ultraviolet in an attempt to detect the presumed nonthermal continuum source thought to be the source of photoionization in the nuclei. NGC 4501 was found to be too faint for study with the IUE spectrographs, while NGC 5005 had an extended ultraviolet light profile. Comparison with the optical light profile of NGC 5005 indicates that the ultraviolet source is distributed spatially in the same manner as the optical starlight, probably indicating that the ultraviolet excess is due to a component of hot stars in the nucleus. These stars contribute detectable absorption features longward of 2500 A; together with optical data, the IUE spectra suggest a burst of star formation about 1 billion yr ago, with a lower rate continuing to produce a few OB stars. In NGC 4579, a point source contributing most of the ultraviolet excess is found that is much different than the optical light distribution. Furthermore, the ultraviolet to X-ray spectral index in NGC 4579 is 1.4, compatible with the UV to X-ray indices found for samples of Seyfert galaxies. This provides compelling evidence for the detection of the photoionizing continuum in NGC 4579 and draws the research fields of normal galaxies and active galactic nuclei closer together. The emission-line spectrum of NGC 4579 is compared with calculations from a photoionization code, CLOUDY, and several shock models. The photoionization code is found to give superior results, adding to the increasing weight of evidence that the LINER phenomenon is essentially a scaled-down version of the Seyfert phenomenon.

  17. Impact of Inner Surface Perturbations on the Stability of Cylindrical Liner Implosion

    NASA Astrophysics Data System (ADS)

    Weis, Matthew; Peterson, Kyle; Hess, Mark; Lau, Y. Y.; Zhang, Peng; Gilgenbach, Ronald

    2015-11-01

    This paper studies the effects of initial perturbations on the inner liner surface (ILS) of an imploding cylindrical liner. In MagLIF, nonuniform preheat of the fuel could provide an additional source of spatial nonuniformity on the ILS. A blast wave generated by the laser preheat might trigger the Richtmyer-Meshkov instability (RM) on the ILS which then serves as another seed to the Rayleigh-Taylor instability (RT) during the stagnation (deceleration) phase of the implosion. Another scenario is that the shock initiated from the outer liner surface, during current rise, propagates inward and is reflected at the ILS. This reflected shock would carry the initial ILS perturbations which then serve as an additional seed for the magneto-RT (MRT) during the acceleration phase of the implosion. These potentially dangerous interactions are analyzed using the 2D HYDRA code. The effects of axial magnetic fields, of the initial surface roughness spectrum, and of gas fill or water fill (to examine deceleration phase RT) are studied. M. R. Weis was supported by the Sandia National Laboratories. This work was also supported by DoE Grant DE-SC0012328.

  18. Semi-analytic modeling and simulation of magnetized liner inertial fusion

    NASA Astrophysics Data System (ADS)

    McBride, R. D.; Slutz, S. A.; Hansen, S. B.

    2013-10-01

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) pre-heat of the fuel; (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, and internal magnetic pressure and heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) deuterium-deuterium and deuterium-tritium primary fusion reactions; and (9) magnetized alpha-particle heating. We will first show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper. We will then use this model to illustrate the MagLIF parameter space, energetics, and efficiencies, and to show the experimental challenges that we will likely be facing as we begin testing MagLIF using the infrastructure presently available at the Z facility. Finally, we will demonstrate how this scenario could likely change as various facility upgrades are made over the next three to five years and beyond. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  19. Fretting and Corrosion Between a Metal Shell and Metal Liner May Explain the High Rate of Failure of R3 Modular Metal-on-Metal Hips.

    PubMed

    Ilo, Kevin C; Derby, Emma J; Whittaker, Robert K; Blunn, Gordon W; Skinner, John A; Hart, Alister J

    2017-05-01

    The R3 acetabular system used with its metal liner has higher revision rates when compared to its ceramic and polyethylene liner. In June 2012, the medical and healthcare products regulatory agency issued an alert regarding the metal liner of the R3 acetabular system. Six retrieved R3 acetabular systems with metal liners underwent detailed visual analysis using macroscopic and microscopic techniques. Visual analysis discovered corrosion on the backside of the metal liners. There was a distinct border to the areas of corrosion that conformed to antirotation tab insertions on the inner surface of the acetabular shell, which are for the polyethylene liner. Scanning electron microscopy indicated evidence of crevice corrosion, and energy-dispersive X-ray analysis confirmed corrosion debris rich in titanium. The high failure rate of the metal liner option of the R3 acetabular system may be attributed to corrosion on the backside of the liner which appear to result from geometry and design characteristics of the acetabular shell. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. 49 CFR 179.400 - General specification applicable to cryogenic liquid tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... liquid tank car tanks. 179.400 Section 179.400 Transportation Other Regulations Relating to... MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and... liquid tank car tanks. ...

  1. 49 CFR 179.100 - General specifications applicable to pressure tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... car tanks. 179.100 Section 179.100 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100 General specifications applicable to pressure tank car tanks. ...

  2. 49 CFR 179.100 - General specifications applicable to pressure tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... car tanks. 179.100 Section 179.100 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100 General specifications applicable to pressure tank car tanks. ...

  3. 49 CFR 179.100 - General specifications applicable to pressure tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... car tanks. 179.100 Section 179.100 Transportation Other Regulations Relating to Transportation... REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100 General specifications applicable to pressure tank car tanks. ...

  4. 49 CFR 179.100 - General specifications applicable to pressure tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... car tanks. 179.100 Section 179.100 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100 General specifications applicable to pressure tank car tanks. ...

  5. The Application of a Novel Ceramic Liner Improves Bonding between Zirconia and Veneering Porcelain

    PubMed Central

    Lee, Hee-Sung

    2017-01-01

    The adhesion of porcelain to zirconia is a key factor in the success of bilayered restorations. In this study, the efficacy of a novel experimental liner (EL) containing zirconia for improved bonding between zirconia and veneering porcelain was tested. Four ELs containing various concentrations (0, 3.0, 6.0, and 9.0 wt %) of zirconia were prepared. Testing determined the most effective EL (EL3 containing 3.0 wt % zirconia) in terms of shear bond strength value (n = 15). Three different bar-shaped zirconia/porcelain bilayer specimens were prepared for a three-point flexural strength (TPFS) test (n = 15): no-liner (NL), commercial liner (CL), and EL3. Specimens were tested for TPFS with the porcelain under tension and the maximum load was measured at the first sign of fracture. The strength data were analyzed using one-way ANOVA and Tukey’s test (α = 0.05) as well as Weibull distribution. When compared to NL, the CL application had no effect, while the EL3 application had a significant positive effect (p < 0.001) on the flexural strength. Weibull analysis also revealed the highest shape and scale parameters for group EL3. Within the limitations of this study, the novel ceramic liner containing 3.0 wt % zirconia (EL3) significantly enhanced the zirconia/porcelain interfacial bonding. PMID:28869512

  6. Life Cycle, Morphology, Ontogenesis, and Phylogeny of Bromeliothrix metopoides nov. gen., nov. spec., a Peculiar Ciliate (Protista, Colpodea) from Tank Bromeliads (Bromeliaceae)

    PubMed Central

    FOISSNER, Wilhelm

    2011-01-01

    Summary Bromeliothrix metopoides was discovered in tank bromeliads from Central and South America. Pure cultures could be established in various media stimulating growth of its food, i.e. bacteria and heterotrophic flagellates of the genus Polytomella. The new ciliate was investigated in the light- and scanning electron microscope, with various silver impregnation techniques, and with molecular methods, using the small-subunit rDNA. The morphology and its changes during the life cycle are documented by 167 figures and a detailed morphometry. Bromeliothrix metopoides is about 27–55 × 22–36 μm in size and has a complex life cycle with Metopus-shaped, bacteriophagous theronts and trophonts (microstomes) and obovate, flagellate-feeding macrostomes having a large, triangular oral apparatus. The thin-walled resting cysts of the theronts and trophonts are uniquely ellipsoidal, while the thick-walled cyst of the macrostome morph is globular. Reproduction occurs in freely motile condition either by binary fission or polytomy, producing a unique, motile “division chain” composed of four globular offspring, of which the central ones are connected by a curious, plug-like holdfast. Division is associated with a complete reorganization of the parental oral and somatic infraciliature. Stomatogenesis is merotelokinetal as in other members of the order Colpodida. The right polykinetid is generated by the rightmost postoral kinety, while the left polykinetid is produced by the two left postoral kineties and five left side kineties. The division in freely motile condition resembles the Exocolpodidae Foissner et al., 2002, to which Bromeliothrix is tentatively assigned, differing from Exocolpoda mainly by the formation of a macrostome morph and a division chain. Bromeliothrix has a ciliary and silverline pattern typical for members of the family Colpodidae. This matches the molecular classification which, however, hardly reflects the outstanding division and life cycle

  7. Life Cycle, Morphology, Ontogenesis, and Phylogeny of Bromeliothrix metopoides nov. gen., nov. spec., a Peculiar Ciliate (Protista, Colpodea) from Tank Bromeliads (Bromeliaceae).

    PubMed

    Foissner, Wilhelm

    2010-11-15

    Bromeliothrix metopoides was discovered in tank bromeliads from Central and South America. Pure cultures could be established in various media stimulating growth of its food, i.e. bacteria and heterotrophic flagellates of the genus Polytomella. The new ciliate was investigated in the light- and scanning electron microscope, with various silver impregnation techniques, and with molecular methods, using the small-subunit rDNA. The morphology and its changes during the life cycle are documented by 167 figures and a detailed morphometry. Bromeliothrix metopoides is about 27-55 × 22-36 μm in size and has a complex life cycle with Metopus-shaped, bacteriophagous theronts and trophonts (microstomes) and obovate, flagellate-feeding macrostomes having a large, triangular oral apparatus. The thin-walled resting cysts of the theronts and trophonts are uniquely ellipsoidal, while the thick-walled cyst of the macrostome morph is globular. Reproduction occurs in freely motile condition either by binary fission or polytomy, producing a unique, motile "division chain" composed of four globular offspring, of which the central ones are connected by a curious, plug-like holdfast. Division is associated with a complete reorganization of the parental oral and somatic infraciliature. Stomatogenesis is merotelokinetal as in other members of the order Colpodida. The right polykinetid is generated by the rightmost postoral kinety, while the left polykinetid is produced by the two left postoral kineties and five left side kineties. The division in freely motile condition resembles the Exocolpodidae Foissner et al., 2002, to which Bromeliothrix is tentatively assigned, differing from Exocolpoda mainly by the formation of a macrostome morph and a division chain. Bromeliothrix has a ciliary and silverline pattern typical for members of the family Colpodidae. This matches the molecular classification which, however, hardly reflects the outstanding division and life cycle, suggesting some

  8. Method of providing a lunar habitat from an external tank

    NASA Technical Reports Server (NTRS)

    King, Charles B. (Inventor); Hypes, Warren D. (Inventor); Simonsen, Lisa C. (Inventor); Butterfield, Ansel J. (Inventor); Nealy, John E. (Inventor); Hall, Jr., John B. (Inventor)

    1992-01-01

    A lunar habitat is provided by placing an external tank of an orbiter in a low Earth orbit where the hydrogen tank is separated from the intertank and oxygen tank which form a base structure. The base structure is then outfitted with an air lock, living quarters, a thermal control system, an environmental control and life support system, and a propulsion system. After the mounting of an outer sheath about the base structure to act as a micrometeoroid shield, the base structure is propelled to a soft landing on the moon. The sheath is mounted at a distance from the base structure to provide a space therebetween which is filled with regolith after landing. Conveniently, a space station is used to outfit the base structure. Various elements of the oxygen tank and intertank are used in outfitting.

  9. Transition duct system with arcuate ceramic liner for delivering hot-temperature gases in a combustion turbine engine

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

    Wiebe, David J.

    A transition duct system (10) for delivering hot-temperature gases from a plurality of combustors in a combustion turbine engine is provided. The system includes an exit piece (16) for each combustor. The exit piece may include an arcuate connecting segment (36). An arcuate ceramic liner (60) may be inwardly disposed onto a metal outer shell (38) along the arcuate connecting segment of the exit piece. Structural arrangements are provided to securely attach the ceramic liner in the presence of substantial flow path pressurization. Cost-effective serviceability of the transition duct systems is realizable since the liner can be readily removed andmore » replaced as needed.« less

  10. Comparison between initial Magnetized Liner Inertial Fusion experiments and integrated simulations

    NASA Astrophysics Data System (ADS)

    Sefkow, A. B.; Gomez, M. R.; Geissel, M.; Hahn, K. D.; Hansen, S. B.; Harding, E. C.; Peterson, K. J.; Slutz, S. A.; Koning, J. M.; Marinak, M. M.

    2014-10-01

    The Magnetized Liner Inertial Fusion (MagLIF) approach to ICF has obtained thermonuclear fusion yields using the Z facility. Integrated magnetohydrodynamic simulations provided the design for the first neutron-producing experiments using capabilities that presently exist, and the initial experiments measured stagnation radii rstag < 75 μm, temperatures around 3 keV, and isotropic neutron yields up to YnDD = 2 ×1012 from imploded liners reaching peak velocities around 70 km/s over an implosion time of about 60 ns. We present comparisons between the experimental observables and post-shot degraded integrated simulations. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  11. Monitoring and analysis of liquid storage in LNG tank based on different support springs

    NASA Astrophysics Data System (ADS)

    He, Hua; Sun, Jianping; Li, Ke; Wu, Zheng; Chen, Qidong; Chen, Guodong; Cao, Can

    2018-04-01

    With the rapid development of social modernization, LNG vehicles are springing up in daily life. However, it is difficult to monitor and judge the liquid storage tanks accurately and quickly. Based on this, this paper presents a new method of liquid storage monitoring, LNG tank on-line vibration monitoring system. By collecting the vibration frequency of LNG tank and tank liquid and supporting spring system, the liquid storage quality in the tank can be calculated. In this experiment, various vibration modes of the tank spring system are fully taken into account. The vibration effects of different types of support springs on the LNG tank system were investigated. The results show that the spring model has a great influence on the test results. This study provides a technical reference for the selection of suitable support springs for liquid storage monitoring.

  12. Fusion Ignition Rocket Engine with Ballistic Ablative Lithium Liner

    NASA Technical Reports Server (NTRS)

    Martin, Adam; Eskridge, Richard; Fimognari, Peter J., III.

    2005-01-01

    Thermo-nuclear fusion may be the key to a high Isp, high specific power (low alpha) propulsion system. In a fusion system energy is liberated within, and imparted directly to, the propellant. In principle, this can overcome the performance limitations inherent in systems that require thermal power transfer across a material boundary, and/or multiple power conversion stages (NTR, NEP). A thermo-nuclear propulsion system, which attempts to overcome some of the problems inherent in the ORION concept, is described. A passive tapered liner is launched behind a vehicle, through a hole in a pusher-plate, that is connected to the vehicle by a shock-absorbing mechanism. A dense FRC plasmoid is then accelerated to high velocity (in excess of 1,000 km/s) and shot through the hole into the liner, when it has reached a given point down-range. The kinetic energy of the FRC is converted into thermal and magnetic-field energy, igniting a fusion bum in the magnetically confined plasma. The fusion reaction serves as an ignition source for the liner, which is made out of detonable materials. The energy liberated in this process is converted to thrust by the pusher-plate, as in the classic ORION concept. However with this concept, the vehicle does not carry a magazine of pre-fabricated pulse-units. A magnetic nozzle may also be used, in place of the pusher-plate. Estimates of the conditions needed to achieve a sufficient gain will be presented, along with a description of the driver characteristics. The incorporation of this concept into the propulsion system of a spacecraft will also be discussed.

  13. 49 CFR 179.102 - Special commodity requirements for pressure tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... car tanks. 179.102 Section 179.102 Transportation Other Regulations Relating to Transportation... REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102 Special commodity requirements for pressure tank car tanks. (a) In addition to...

  14. A sub-tank water-saving drinking water station

    NASA Astrophysics Data System (ADS)

    Zhang, Ting

    2017-05-01

    "Thousands of boiling water" problem has been affecting people's quality of life and good health, and now most of the drinking fountains cannot effectively solve this problem, at the same time, ordinary drinking water also has high energy consumption, there are problems such as yin and yang water. Our newly designed dispenser uses a two-tank heating system. Hot water after heating, into the insulation tank for insulation, when the water tank in the water tank below a certain water level, the cold water and then enter the heating tank heating. Through the water flow, tank volume and other data to calculate the time required for each out of water, so as to determine the best position of the water level control, summed up the optimal program, so that water can be continuously uninterrupted supply. Two cans are placed up and down the way, in the same capacity on the basis of the capacity of the container, the appropriate to reduce its size, and increase the bottom radius, reduce the height of its single tank to ensure that the overall height of two cans compared with the traditional single change. Double anti-dry design, to ensure the safety of the use of drinking water. Heating tank heating circuit on and off by the tank of the float switch control, so that the water heating time from the tank water level control, to avoid the "thousands of boiling water" generation. The entry of cold water is controlled by two solenoid valves in the inlet pipe, and the opening and closing of the solenoid valve is controlled by the float switch in the two tanks. That is, the entry of cold water is determined by the water level of the two tanks. By designing the control scheme cleverly, Yin and yang water generation. Our design completely put an end to the "thousands of boiling water", yin and yang water, greatly improving the drinking water quality, for people's drinking water safety provides a guarantee, in line with the concept of green and healthy development. And in the small

  15. Testing and design life analysis of polyurea liner materials

    NASA Astrophysics Data System (ADS)

    Ghasemi Motlagh, Siavash

    Certainly, water pipes, as part of an underground infrastructure system, play a key role in maintaining quality of life, health, and wellbeing of human kind. As these potable water pipes reach the end of their useful life, they create high maintenance costs, loss of flow capacity, decreased water quality, and increased dissatisfaction. There are several different pipeline renewal techniques available for different applications, among which linings are most commonly used for the renewal of water pipes. Polyurea is a lining material applied to the interior surface of the deteriorated host pipe using spray-on technique. It is applied to structurally enhance the host pipe and provide a barrier coating against further corrosion or deterioration. The purpose of this study was to establish a relationship between stress, strain and time. The results obtained from these tests were used in predicting the strength of the polyurea material during its planned 50-year design life. In addition to this, based on the 10,000 hours experimental data, curve fitting and Findley power law models were employed to predict long-term behavior of the material. Experimental results indicated that the tested polyurea material offers a good balance of strength and stiffness and can be utilized in structural enhancement applications of potable water pipes.

  16. A tank-to-wheel analysis tool for energy and emissions studies in road vehicles.

    PubMed

    Silva, C M; Gonçalves, G A; Farias, T L; Mendes-Lopes, J M C

    2006-08-15

    Currently, oil based fuels are the primary energy source of road transport. The growing need for oil independence and CO(2) mitigation has lead to the increasing importance of alternative fuel usage. CO(2) is produced not only as the fuel is used in the vehicle (tank-to-wheel contribution), but also upstream, from the fuel extraction to the refueling station (well-to-tank contribution), and the life cycle of the fuel production (well-to-wheel contribution) must be considered in order to analyse the global impact of the fuel utilization. A road vehicle tank-to-wheel analysis tool that may be integrated with well-to-tank models was developed in the present study. The integration in a demonstration case study allowed to perform a life cycle assessment concerning the utilization of diesel and natural gas fuels in a specific network line of a bus transit company operating in the city of Porto, Portugal.

  17. Cross-hole fracture connectivity assessed using hydraulic responses during liner installations in crystalline bedrock boreholes

    NASA Astrophysics Data System (ADS)

    Persaud, Elisha; Levison, Jana; Pehme, Peeter; Novakowski, Kentner; Parker, Beth

    2018-01-01

    In order to continually improve the current understanding of flow and transport in crystalline bedrock environments, developing and improving fracture system characterization techniques is an important area of study. The presented research examines the installation of flexible, impermeable FLUTe™ liners as a means for assessing cross-hole fracture connectivity. FLUTe™ liners are used to generate a new style of hydraulic pulse, with pressure response monitored in a nearby network of open boreholes drilled in gneissic rock of the Canadian Shield in eastern Ontario, Canada. Borehole liners were installed in six existing 10-15 cm diameter boreholes located 10-35 m apart and drilled to depths ranging between 25-45 m. Liner installation tests were completed consecutively with the number of observation wells available for each test ranging between one and six. The collected pressure response data have been analyzed to identify significant groundwater flow paths between source and observation boreholes as well as to estimate inter-well transmissivity and storativity using a conventional type-curve analysis. While the applied solution relies on a number of general assumptions, it has been found that reasonable comparison can be made to previously completed pulse interference and pumping tests. Results of this research indicate areas where method refinement is necessary, but, nonetheless, highlight the potential for use in crystalline bedrock environments. This method may provide value to future site characterization efforts given that it is complementary to, and can be used in conjunction with, other currently employed borehole liner applications, such as the removal of cross-connection at contaminated sites and the assessment of discrete fracture distributions when boreholes are sealed, recreating natural hydraulic gradient conditions.

  18. Modeling the interactions between a prosthetic socket, polyurethane liners and the residual limb in transtibial amputees using non-linear finite element analysis.

    PubMed

    Simpson, G; Fisher, C; Wright, D K

    2001-01-01

    Continuing earlier studies into the relationship between the residual limb, liner and socket in transtibial amputees, we describe a geometrically accurate non-linear model simulating the donning of a liner and then a socket. The socket is rigid and rectified and the liner is a polyurethane geltype which is accurately described using non-linear (Mooney-Rivlin) material properties. The soft tissue of the residual limb is modelled as homogeneous, non-linear and hyperelastic and the bone structure within the residual limb is taken as rigid. The work gives an indication of how the stress induced by the process of donning the rigid socket is redistributed by the liner. Ultimately we hope to understand how the liner design might be modified to reduce discomfort. The ANSYS finite element code, version 5.6 is used.

  19. Effect of different surface treatments on tensile bond strength of silicone-based soft denture liner.

    PubMed

    Akin, Hakan; Tugut, Faik; Mutaf, Burcu; Akin, Gulsah; Ozdemir, A Kemal

    2011-11-01

    Failure of the bond between the acrylic resin and resilient liner material is commonly encountered in clinical practice. The purpose of this study was to investigate the effect of different surface treatments (sandblasting, Er:YAG, Nd:YAG, and KTP lasers) on tensile bond strength of silicone-based soft denture liner. Polymethyl methacrylate test specimens were fabricated and each received one of eight surface treatments: untreated (control), sandblasted, Er:YAG laser irradiated, sandblasted + Er:YAG laser irradiated, Nd:YAG laser irradiated, sandblasted + Nd:YAG laser irradiated, KTP laser irradiated, and sandblasted + KTP laser irradiated. The resilient liner specimens (n = 15) were processed between two polymethyl methacrylate (PMMA) blocks. Bonding strength of the liners to PMMA were compared by tensile test with the use of a universal testing machine at a crosshead speed of 5 mm/min. Kruskal-Wallis and Wilcoxon tests were used to analyze the data (α = 0.05). Altering the polymethyl methacrylate surface by Er:YAG laser significantly increased the bond strengths in polymethyl methacrylate/silicone specimens, however, sandblasting before applying a lining material had a weakening effect on the bond. In addition, Nd:YAG and KTP lasers were found to be ineffective for increasing the strength of the bond.

  20. 49 CFR 179.102 - Special commodity requirements for pressure tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... car tanks. 179.102 Section 179.102 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102 Special commodity requirements for pressure tank car tanks. (a) In addition to §§ 179.100 and...

  1. 49 CFR 179.102 - Special commodity requirements for pressure tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... car tanks. 179.102 Section 179.102 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102 Special commodity requirements for pressure tank car tanks. (a) In addition to §§ 179.100 and...

  2. 49 CFR 179.102 - Special commodity requirements for pressure tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... car tanks. 179.102 Section 179.102 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.102 Special commodity requirements for pressure tank car tanks. (a) In addition to §§ 179.100 and...

  3. HEATING AND COOLING SYSTEM FOR CALUTRON

    DOEpatents

    Starr, A.M.

    1960-06-28

    An apparatus is invented for heating or cooling the electrostatic liner conventionally disposed in a calutron tank. The apparatus is additionally arranged to mount the liner in its intended position in a readily detachable manner so as to facilitate disassembly of the calutron.

  4. VizieR Online Data Catalog: SFR & AGN in most luminous local universe LINERs (Povic+, 2016)

    NASA Astrophysics Data System (ADS)

    Povic, M.; Marquez, I.; Netzer, H.; Masegosa, J.; Nordon, R.; Perez, E.; Schoenell, W.

    2018-02-01

    The sources were initially selected from the SDSS/DR4 (Kauffmann et al., 2003MNRAS.341...33K; Brinchmann et al., 2004MNRAS.351.1151B) catalogue in Garching MPA-JHU based on the SDSS (http://www.sdss.org/) DR4 data (Adelman-McCarthy et al. (2006ApJS..162...38A, Cat. II/267), and references therein). LINERs were first selected using both [NII]6584/Hα and [OI]6300/Hα criteria of Kewley et al. (2006MNRAS.372..961K). Taking into account the completeness of the SDSS survey, only LINERs with 0.04LINERs ionized by pAGB stars, we selected only those galaxies with Hα EW(Hα)>2.5Å (Cid-Fernandes et al., 2011MNRAS.413.1687C). (8 data files).

  5. 27 CFR 24.230 - Examination of tank car or tank truck.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Examination of tank car or... TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Spirits § 24.230 Examination of tank car or tank truck. Upon arrival of a tank car or tank truck at the bonded wine premises, the proprietor shall...

  6. 27 CFR 24.230 - Examination of tank car or tank truck.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Examination of tank car or... TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Spirits § 24.230 Examination of tank car or tank truck. Upon arrival of a tank car or tank truck at the bonded wine premises, the proprietor shall...

  7. 27 CFR 24.230 - Examination of tank car or tank truck.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Examination of tank car or... TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.230 Examination of tank car or tank truck. Upon arrival of a tank car or tank truck at the bonded wine premises, the proprietor shall...

  8. 27 CFR 24.230 - Examination of tank car or tank truck.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Examination of tank car or... TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.230 Examination of tank car or tank truck. Upon arrival of a tank car or tank truck at the bonded wine premises, the proprietor shall...

  9. 27 CFR 24.230 - Examination of tank car or tank truck.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Examination of tank car or... TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.230 Examination of tank car or tank truck. Upon arrival of a tank car or tank truck at the bonded wine premises, the proprietor shall...

  10. 49 CFR 179.500 - Specification DOT-107A * * * * seamless steel tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... car tanks. 179.500 Section 179.500 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.500 Specification DOT-107A * * * * seamless steel tank car tanks. ...

  11. 49 CFR 179.101 - Individual specification requirements applicable to pressure tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... to pressure tank car tanks. 179.101 Section 179.101 Transportation Other Regulations Relating to... MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT... tank car tanks. Editorial Note: At 66 FR 45186, Aug. 28, 2001, an amendment published amending a table...

  12. 49 CFR 179.400 - General specification applicable to cryogenic liquid tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... liquid tank car tanks. 179.400 Section 179.400 Transportation Other Regulations Relating to... (CONTINUED) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400 General specification applicable to cryogenic liquid tank car...

  13. 49 CFR 179.500 - Specification DOT-107A * * * * seamless steel tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... car tanks. 179.500 Section 179.500 Transportation Other Regulations Relating to Transportation... REGULATIONS SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.500 Specification DOT-107A * * * * seamless steel tank car tanks. ...

  14. 49 CFR 179.500 - Specification DOT-107A * * * * seamless steel tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... car tanks. 179.500 Section 179.500 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.500 Specification DOT-107A * * * * seamless steel tank car tanks. ...

  15. 49 CFR 179.500 - Specification DOT-107A * * * * seamless steel tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... car tanks. 179.500 Section 179.500 Transportation Other Regulations Relating to Transportation...) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.500 Specification DOT-107A * * * * seamless steel tank car tanks. ...

  16. 49 CFR 179.400 - General specification applicable to cryogenic liquid tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... liquid tank car tanks. 179.400 Section 179.400 Transportation Other Regulations Relating to... (CONTINUED) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400 General specification applicable to cryogenic liquid tank car...

  17. 49 CFR 179.400 - General specification applicable to cryogenic liquid tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... liquid tank car tanks. 179.400 Section 179.400 Transportation Other Regulations Relating to... (CONTINUED) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400 General specification applicable to cryogenic liquid tank car...

  18. Double-Shell Tank Visual Inspection Changes Resulting from the Tank 241-AY-102 Primary Tank Leak

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

    Girardot, Crystal L.; Washenfelder, Dennis J.; Johnson, Jeremy M.

    2013-11-14

    As part of the Double-Shell Tank (DST) Integrity Program, remote visual inspections are utilized to perform qualitative in-service inspections of the DSTs in order to provide a general overview of the condition of the tanks. During routine visual inspections of tank 241-AY-102 (AY-102) in August 2012, anomalies were identified on the annulus floor which resulted in further evaluations. In October 2012, Washington River Protection Solutions, LLC determined that the primary tank of AY-102 was leaking. Following identification of the tank AY-102 probable leak cause, evaluations considered the adequacy of the existing annulus inspection frequency with respect to the circumstances ofmore » the tank AY-102 1eak and the advancing age of the DST structures. The evaluations concluded that the interval between annulus inspections should be shortened for all DSTs, and each annulus inspection should cover > 95 percent of annulus floor area, and the portion of the primary tank (i.e., dome, sidewall, lower knuckle, and insulating refractory) that is visible from the annulus inspection risers. In March 2013, enhanced visual inspections were performed for the six oldest tanks: 241-AY-101, 241-AZ-101,241-AZ-102, 241-SY-101, 241-SY-102, and 241-SY-103, and no evidence of leakage from the primary tank were observed. Prior to October 2012, the approach for conducting visual examinations of DSTs was to perform a video examination of each tank's interior and annulus regions approximately every five years (not to exceed seven years between inspections). Also, the annulus inspection only covered about 42 percent of the annulus floor.« less

  19. Dynamic Behaviour and Seismic Response of Ground Supported Cylindrical Water Tanks

    NASA Astrophysics Data System (ADS)

    Asha, Joseph; Glory, Joseph

    2018-05-01

    Liquid storage tank such as in water distribution systems, petroleum plants etc., constitute a vital component of life line systems. Reducing earthquake effects on liquid storage tanks, to minimize the environmental and economic impact of these effects, have always been an important engineering concern. In this paper, the dynamic behavior of cylindrical ground supported concrete water tanks with different aspect ratios is investigated using finite element software ANSYS. The natural frequencies and modal responses are obtained for impulsive and convective modes of vibration. The natural frequency of vibration of the tank is observed to be the lowest at maximum water depth. The fundamental impulsive frequency increases as water level reduces and for water level less than 1/3 of tank height, there is significantly no change in impulsive frequency. The effect of wall flexibility on dynamic behavior of the tank is investigated by performing the modal analysis of flexible and rigid tanks. For a partially filled tank, the results of the present study are of significant relevance. The response of the tank to the transient loading as horizontal ground motion of El Centro earthquake is studied for various water heights. As the height of water on the tank increases, the ultimate maximum seismic response parameters are also observed to be increased. The location of maximum hoop stress varies in accordance with the variations in input ground motion and water fill condition whereas shear and bending moment are maximum at the base.

  20. 33 CFR 157.147 - Similar tank design: Inspections on foreign tank vessels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Similar tank design: Inspections... § 157.147 Similar tank design: Inspections on foreign tank vessels. (a) If a foreign tank vessel has..., for only one of those tanks to be inspected under § 157.140(a)(1). (b) Only one tank of a group of...

  1. 27 CFR 27.174 - Tank cars and tank trucks to be sealed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Tank cars and tank trucks... Tank cars and tank trucks to be sealed. Where a shipment of distilled spirits from customs custody to the distilled spirits plant is made in a tank car or tank truck, all openings affording access to the...

  2. 27 CFR 27.174 - Tank cars and tank trucks to be sealed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Tank cars and tank trucks... Tank cars and tank trucks to be sealed. Where a shipment of distilled spirits from customs custody to the distilled spirits plant is made in a tank car or tank truck, all openings affording access to the...

  3. 27 CFR 27.174 - Tank cars and tank trucks to be sealed.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Tank cars and tank trucks... Tank cars and tank trucks to be sealed. Where a shipment of distilled spirits from customs custody to the distilled spirits plant is made in a tank car or tank truck, all openings affording access to the...

  4. 46 CFR 153.250 - Double-bottom and deep tanks as cargo tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Double-bottom and deep tanks as cargo tanks. 153.250... Equipment Cargo Tanks § 153.250 Double-bottom and deep tanks as cargo tanks. Except in those cases in which Commandant (CG-522) specifically approves another arrangement, such as a double-bottom or deep tank as a...

  5. 46 CFR 153.250 - Double-bottom and deep tanks as cargo tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Double-bottom and deep tanks as cargo tanks. 153.250... Equipment Cargo Tanks § 153.250 Double-bottom and deep tanks as cargo tanks. Except in those cases in which Commandant (CG-ENG) specifically approves another arrangement, such as a double-bottom or deep tank as a...

  6. 46 CFR 153.250 - Double-bottom and deep tanks as cargo tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Double-bottom and deep tanks as cargo tanks. 153.250... Equipment Cargo Tanks § 153.250 Double-bottom and deep tanks as cargo tanks. Except in those cases in which Commandant (CG-522) specifically approves another arrangement, such as a double-bottom or deep tank as a...

  7. 46 CFR 153.250 - Double-bottom and deep tanks as cargo tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Double-bottom and deep tanks as cargo tanks. 153.250... Equipment Cargo Tanks § 153.250 Double-bottom and deep tanks as cargo tanks. Except in those cases in which Commandant (CG-ENG) specifically approves another arrangement, such as a double-bottom or deep tank as a...

  8. 46 CFR 153.250 - Double-bottom and deep tanks as cargo tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Double-bottom and deep tanks as cargo tanks. 153.250... Equipment Cargo Tanks § 153.250 Double-bottom and deep tanks as cargo tanks. Except in those cases in which Commandant (CG-ENG) specifically approves another arrangement, such as a double-bottom or deep tank as a...

  9. 49 CFR 179.301 - Individual specification requirements for multi-unit tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-unit tank car tanks. 179.301 Section 179.301 Transportation Other Regulations Relating to... (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.301 Individual specification requirements for multi-unit tank car tanks. (a) In addition to...

  10. 49 CFR 179.301 - Individual specification requirements for multi-unit tank car tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-unit tank car tanks. 179.301 Section 179.301 Transportation Other Regulations Relating to... MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.301 Individual specification requirements for multi-unit tank car tanks. (a) In...

  11. 49 CFR 179.301 - Individual specification requirements for multi-unit tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-unit tank car tanks. 179.301 Section 179.301 Transportation Other Regulations Relating to... (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.301 Individual specification requirements for multi-unit tank car tanks. (a) In addition to...

  12. 49 CFR 179.301 - Individual specification requirements for multi-unit tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-unit tank car tanks. 179.301 Section 179.301 Transportation Other Regulations Relating to... (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.301 Individual specification requirements for multi-unit tank car tanks. (a) In addition to...

  13. 241-AY-101 Tank Construction Extent of Condition Review for Tank Integrity

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

    Barnes, Travis J.; Gunter, Jason R.

    2013-08-26

    This report provides the results of an extent of condition construction history review for tank 241-AY-101. The construction history of tank 241-AY-101 has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In tank 241-AY-101, the second double-shell tank constructed, similar issues as those with tank 241-AY-102 construction reoccurred. The overall extent of similary and affect on tank 241-AY-101 integrity is described herein.

  14. 241-AP Tank Farm Construction Extent of Condition Review for Tank Integrity

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

    Barnes, Travis J.; Gunter, Jason R.; Reeploeg, Gretchen E.

    2014-04-04

    This report provides the results of an extent of condition construction history review for the 241-AP tank farm. The construction history of the 241-AP tank farm has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In the 241-AP tank farm, the sixth double-shell tank farm constructed, tank bottom flatness, refractory material quality, post-weld stress relieving, and primary tank bottom weld rejection were improved.

  15. Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners.

    PubMed

    Arora, Rajesh; Kapur, Ravi; Sibal, Nikhil; Juneja, Sumit

    2012-09-01

    The advent of the esthetic era and advances in adhesive technology saw the emergence of resin composite materials. But the problem of polymerization shrinkage remained. This was due to the contraction of the resin during curing inducing internal and interfacial stresses at the tooth restoration interface, leading to gap formation and subsequent micro-leakage. A number of techniques and modifications in the material have been proposed to minimize polymerization shrinkage and microleakage. In this study, the hypothesis that the placement of resin-modified glass ionomer cement (RMGIC) or flowable composite, as liner, beneath the packable composite, on the gingival surface of the tooth [coronal or apical to cementoenamel junction (CEJ)], could reduce the microleakage in class II composite restorations, was tested. Sixty recently extracted noncarious human mandibular molars were used. The teeth were randomly divided into three groups (20 specimens each): Group I (Filtek P60 with RMGIC liner), group II (Filtek P60 with Filtek Z350 liner) and Group III (Filtek P60 without liner). The teeth of each group were further subdivided into two subgroups (equal number of cavities). Subgroup A gingival seat 1 mm occlusal to CEJ on mesial side. Subgroup B gingival seat 1 mm apical to CEJ on distal side. It was concluded that in class II composite restorations gingival microleakage is more at the dentinal surface than on enamel. The use of a flowable composite and RMGIC, as liners, beneath the packable composite, in class II composite restorations, significantly reduces the microleakage when margins are in dentin, but the reverse is true, when the margins are in enamel. How to cite this article: Arora R, Kapur R, Sibal N, Juneja S. Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners. Int J Clin Pediatr Dent 2012;5(3):178-184.

  16. 49 CFR 180.519 - Periodic retest and inspection of tank cars other than single-unit tank car tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Periodic retest and inspection of tank cars other than single-unit tank car tanks. 180.519 Section 180.519 Transportation Other Regulations Relating to... (CONTINUED) CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS Qualification and Maintenance of Tank Cars...

  17. 49 CFR 180.519 - Periodic retest and inspection of tank cars other than single-unit tank car tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Periodic retest and inspection of tank cars other than single-unit tank car tanks. 180.519 Section 180.519 Transportation Other Regulations Relating to... (CONTINUED) CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS Qualification and Maintenance of Tank Cars...

  18. 49 CFR 180.519 - Periodic retest and inspection of tank cars other than single-unit tank car tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Periodic retest and inspection of tank cars other than single-unit tank car tanks. 180.519 Section 180.519 Transportation Other Regulations Relating to... (CONTINUED) CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS Qualification and Maintenance of Tank Cars...

  19. 49 CFR 180.519 - Periodic retest and inspection of tank cars other than single-unit tank car tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Periodic retest and inspection of tank cars other than single-unit tank car tanks. 180.519 Section 180.519 Transportation Other Regulations Relating to... (CONTINUED) CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS Qualification and Maintenance of Tank Cars...

  20. 49 CFR 179.500 - Specification DOT-107A * * * * seamless steel tank car tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Specification DOT-107A * * * * seamless steel tank...) SPECIFICATIONS FOR TANK CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.500 Specification DOT-107A * * * * seamless steel tank car tanks. ...