Sample records for fluid catalytic cracking

  1. Methods applied to investigate the major VCE that occured in the TOTAL refinery's Fluid Catalytic Cracking Unit at La Mede,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    95-35 Methods applied to investigate the major �VCE that occured in the TOTAL refinery's Fluid.V.C.E, occured in the Gas Plant of the TOTAL refinery's Fluid Catalytic Cracking ünit at La Mede, France

  2. Economics for iso-olefin production using the fluid catalytic cracking unit

    SciTech Connect (OSTI)

    McClung, R.G.; Witoshkin, A.; Bogert, D.C.; Winkler, W.S. [Englehard Corp., Iselin, NJ (United States)

    1993-12-31T23:59:59.000Z

    The Clean Air Act of 1990 requires use of oxygenates in some gasolines to improve both CO and hydrocarbon auto tailpipe emissions. Various oxygenates are currently being used by the refining industry. For the fully integrated refinery having a fluid catalytic cracking unit, the most commonly used oxygenates are methyl tertiary butyl ether (MTBE) and tertiary amyl ether (TAME). The FCC unit produces the isobutylene and iso-amylases need for manufacture of both MTBE and TAME. The economics for an assumed refinery processing scheme for several FCC cases are examined giving estimates of income and investments for each case. Up to one-third of the total gasoline pool can be made in reformulated gasoline using TAME and MTBE with the FCC unit as the sole source of feedstock. This processing route is much more economical than the alternative scheme using butane isomerization/iosbutane dehydrogenation.

  3. A lightweight three-phase Fluid Catalytic Cracking riser model for real-time simulation and interactive three-dimensional visualization

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    physical model and a fast numerical solver are proposed for the rendering of fluid catalytic cracking (FCC) dynamics in the riser cylinder reactor part of the FCC unit. For Real Time requirements, a trade, privileged paths for the gas phase, etc. Of course, the rendering is purely qualitative, but accurate enough

  4. Protocol development for evaluation of commercial catalytic cracking catalysts

    SciTech Connect (OSTI)

    Mitchell, M.M. Jr.; Moore, H.F. (Ashland Petroleum Co., KY (USA))

    1988-09-01T23:59:59.000Z

    A complete, new set of testing protocols has been developed for qualification of catalysts for Ashland's commercial catalytic cracking units. The objective of this test development is to identify new generations of improved cracking catalysts. Prior test protocols have classically utilized microactivity (MAT) testing of steamed virgin catalysts, while more advanced methods have utilized fixed fluid bed and/or circulating pilot units. Each of these techniques, however, have been limited by their correlation to commercial operations, weaknesses in metallation and preparation of pseudo-equilibrium catalysts, and mechanical constraints on the use of heavy, vacuum bottoms-containing feedstocks. These new protocols have been baselined, compared to commercial Ashland results on known catalytic cracking catalysts, and utilized to evaluate a range of potentially new catalyst samples.

  5. Catalytic cracking of residual petroleum fractions

    SciTech Connect (OSTI)

    Moore, H.F.; Mayo, S.L.; Goolsby, T.L. (Research and Development Dept., Ashland Petroleum Co., Ashland, KY (US))

    1991-01-01T23:59:59.000Z

    This paper reports on Arabian Light crude oil vacuum bottoms fractionated into five high-boiling fractions by wiped film evaporation, and the fractions subjected to catalytic cracking in a fixed-fluidized bed using a commercial equilibrium cracking catalyst. Density, aromaticity, and heteroatom content generally increased with boiling point, as did metals content except for vanadium and iron which demonstrated possible bimodal distributions. The cracking response of these fractions showed increasing yields of dry gas and coke, with decreasing gasoline yields, as a function of increasing apparent boiling point as would normally be expected. Surprisingly, however, local maxima were observed for wet gas yield and total conversion, with local minima for cycle oil and slurry yields, in the region of the 1200-1263{degrees}F (650-680{degrees}C) middle fraction. All fractions showed significant response to cracking, with coke yields generally being the only negative factor observed.

  6. Cascading of fluid cracking catalysts

    SciTech Connect (OSTI)

    Kovach, S.M.; Miller, C.B.

    1986-05-27T23:59:59.000Z

    A process is described for conversion of hydrocarbon feedstocks by cascading a cracking catalyst containing zeolite in an acidic matrix from one hydrocarbon processing unit to another, wherein there are at least three different interconnected hydrocarbon processing units comprising a first unit having a regeneration zone and a riser zone, a second unit having having a regeneration zone and a riser zone, and a third unit having a riser zone and a regeneration zone, each unit having different processing conditions.

  7. Fluid Catalytic Cracking Power Recovery Computer Simulation

    E-Print Network [OSTI]

    Samurin, N. A.

    1979-01-01T23:59:59.000Z

    operating conditions. The digital computer model simulates the performance of the axial compressor, power recovery expander, regenerator section, and system pressure drops. The program can simulate the process system design conditions for compatibility...

  8. Fluid Catalytic Cracking Power Recovery Computer Simulation 

    E-Print Network [OSTI]

    Samurin, N. A.

    1979-01-01T23:59:59.000Z

    operating conditions. The digital computer model simulates the performance of the axial compressor, power recovery expander, regenerator section, and system pressure drops. The program can simulate the process system design conditions for compatibility...

  9. Diffusion and Catalytic Cracking of 1,3,5 Tri-iso-propyl-benzene in FCC Catalysts

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    1 Diffusion and Catalytic Cracking of 1,3,5 Tri-iso- propyl-benzene in FCC Catalysts S.Al-Khattaf1 describes catalytic cracking experiments developed in a novel CREC Riser Simulator using 1,3,5-Tri-iso

  10. Energy Recovery System for Fluid Catalytic Cracking Units 

    E-Print Network [OSTI]

    Wen, H.; Lou, S. C.

    1982-01-01T23:59:59.000Z

    hot gas expanders. Flue gas from the FCC regenerator passes through a special cyclone separator to remove most of the entrained catalyst fines. It then enters the expander train to generate power for the compressor which supplies air...

  11. Energy Conservation Revamps in Fluid Catalytic Cracking Systems

    E-Print Network [OSTI]

    Wilson, J. W.; Sloan, H. D.

    1984-01-01T23:59:59.000Z

    The FCC process continues as one of the major refinery technologies despite changes in refinery operations. The main fractionator/vapor recovery systems associated with many FCC units have the potential for significant gains in energy efficiency...

  12. Energy Recovery System for Fluid Catalytic Cracking Units

    E-Print Network [OSTI]

    Wen, H.; Lou, S. C.

    1982-01-01T23:59:59.000Z

    hot gas expanders. Flue gas from the FCC regenerator passes through a special cyclone separator to remove most of the entrained catalyst fines. It then enters the expander train to generate power for the compressor which supplies air...

  13. Educating Consumers: New Content on Diesel Vehicles, Diesel Exhaust Fluid, and Selective Catalytic Reduction Technologies on the AFDC (Presentation)

    SciTech Connect (OSTI)

    Brodt-Giles, D.

    2008-08-05T23:59:59.000Z

    Presentation covers new content available on the Alternative Fuels and Advanced Vehicle Data Center regarding diesel vehicles, diesel exhaust fluid, and selective catalytic reduction technologies.

  14. Catalytic gasification studies in a pressurized fluid-bed unit

    SciTech Connect (OSTI)

    Mudge, L.K.; Baker, E.G.; Mitchell, D.H.; Robertus, R.J.; Brown, M.D.

    1983-07-01T23:59:59.000Z

    The purpose of the project is to evaluate the technical and economic feasibility of producing specific gas products via the catalytic gasification of biomass. This report presents the results of research conducted from October 1980 to November 1982. In the laboratory scale studis, active catalysts were developed for generation of synthesis gases from wood by steam gasification. A trimetallic catalyst, Ni-Co-Mo on silica-alumina doped with 2 wt % Na, was found to retain activity indefinitely for generation of a methanol synthesis gas from wood at 1380/sup 0/F (750/sup 0/C) and 1 atm (100 kPa) absolute pressure. Catalysts for generation of a methane-rich gas were deactivated rapidly and could not be regenerated as required for economic application. Sodium carbonate and potassium carbonate were effective as catalysts for conversion of wood to synthesis gases and methane-rich gas and should be economically viable. Catalytic gasification conditions were found to be suitable for processing of alternative feedstocks: bagasse, alfalfa, rice hulls, and almond hulls. The PDU was operated successfully at absolute pressures of up to 10 atm (1000 kPa) and temperatures of up to 1380/sup 0/F (750/sup 0/C). Yields of synthesis gases at elevated pressure were greater than those used for previous economic evaluations. A trimetallic catalyst, Ni-Cu-Mo on silica-alumina, did not display a long life as did the doped trimetallic catalyst used in laboratory studies. A computer program for a Radio Shack TRS-80 Model I microcomputer was developed to evaluate rapidly the economics of producing either methane or methanol from wood. The program is based on economic evaluations reported in previous studies. Improved yields from the PDU studies were found to result in a reduction of about 9 cents/gal in methanol cost.

  15. Reaction kinetics of olefin saturation in the hydrodesulfurization of fluid catalytic cracked naphtha

    E-Print Network [OSTI]

    Schumann, Brian Herbert

    1995-01-01T23:59:59.000Z

    . . . 30 . . . 3 I . . . 3 I 13. Run 222-92-70--Comparison ofkw/rto Carbon Number forNormalOlefin . . . . 32 14. Run 222-92-70 ? -Comparison of k w/r to Carbon Number for Iso Olefins . . . . . . . . . . . 32 15. Run 222-92-70 ? -Comparison of k w.../r to Carbon Number for Cycfic Olefins . . . . . . 33 16. Run 963-94-24 ? -Comparison of k w/r to Carbon Number for Normal Olefins . . . . 33 17. Run 963-94-24 ? -Comparison of k w/r to Carbon Number for Iso Olefins . . . . . . . . . . . 34 18. Run 963...

  16. Process and apparatus for cooling during regeneration of fluid cracking catalyst

    SciTech Connect (OSTI)

    Walters, P.W.; Raiche, H.A.; Harness, R.L.; Quodala, G.M.

    1987-10-06T23:59:59.000Z

    This patent describes an apparatus for the regeneration of coke contaminated fluid cracking catalyst. The combination comprises: A. an elongated upflow regeneration vessel, containing a dense bed of catalyst and a regeneration gas grid located within the bed; B. a vertical heat exchanger mounted to the lower side of the vessel adapted to receive hot catalyst directly from the regeneration vessel and adapted to cool the hot catalyst as it passes downwardly through the exchanger; C. a Y junction positioned below the lower end of the heat exchanger; D. a first conduit means for passing cool catalyst downwardly to the Y junction; E. second conduit means for passing cool catalyst from the Y junction upwardly into the dense bed of catalyst in the regeneration vessel, and F. regeneration gas supply means, separate from the second conduit means, for supplying regeneration gas to the gas grid; G. lift gas supply means, separate from the regeneration gas supply means, for introducing lift gas into the second conduit means so as to lift the cool catalyst up through the second conduit means to the regenerator.

  17. Linear elastic fracture mechanics in anisotropic solids : application to fluid-driven crack propagation

    E-Print Network [OSTI]

    Laubie, Hadrien Hyacinthe

    2013-01-01T23:59:59.000Z

    Fracture mechanics is a field of continuum mechanics with the objective to predict how cracks initiate and propagate in solids. It has a wide domain of application. While aerospace engineers want to make sure a defect in ...

  18. Multiphase Equilibrium of Fluids Confined in Fisher-Tropsch Catalytic Systems 

    E-Print Network [OSTI]

    Warrag, Samah

    2014-04-23T23:59:59.000Z

    Equation of state model extended to confined fluid (PR-C) has been utilized in multiphase equilibrium algorithm using FORTRAN. The simulation results provide the composition and the condition of each bulk phase and pore phase for a given initial mixture...

  19. Fluid-Bed Testing of Greatpoint Energy's Direct Oxygen Injection Catalytic Gasification Process for Synthetic Natural Gas and Hydrogen Coproduction Year 6 - Activity 1.14 - Development of a National Center for Hydrogen Technology

    SciTech Connect (OSTI)

    Swanson, Michael; Henderson, Ann

    2012-04-01T23:59:59.000Z

    The GreatPoint Energy (GPE) concept for producing synthetic natural gas and hydrogen from coal involves the catalytic gasification of coal and carbon. GPE’s technology “refines” coal by employing a novel catalyst to “crack” the carbon bonds and transform the coal into cleanburning methane (natural gas) and hydrogen. The GPE mild “catalytic” gasifier design and operating conditions result in reactor components that are less expensive and produce pipeline-grade methane and relatively high purity hydrogen. The system operates extremely efficiently on very low cost carbon sources such as lignites, subbituminous coals, tar sands, petcoke, and petroleum residual oil. In addition, GPE’s catalytic coal gasification process eliminates troublesome ash removal and slagging problems, reduces maintenance requirements, and increases thermal efficiency, significantly reducing the size of the air separation plant (a system that alone accounts for 20% of the capital cost of most gasification systems) in the catalytic gasification process. Energy & Environmental Research Center (EERC) pilot-scale gasification facilities were used to demonstrate how coal and catalyst are fed into a fluid-bed reactor with pressurized steam and a small amount of oxygen to “fluidize” the mixture and ensure constant contact between the catalyst and the carbon particles. In this environment, the catalyst facilitates multiple chemical reactions between the carbon and the steam on the surface of the coal. These reactions generate a mixture of predominantly methane, hydrogen, and carbon dioxide. Product gases from the process are sent to a gas-cleaning system where CO{sub 2} and other contaminants are removed. In a full-scale system, catalyst would be recovered from the bottom of the gasifier and recycled back into the fluid-bed reactor. The by-products (such as sulfur, nitrogen, and CO{sub 2}) would be captured and could be sold to the chemicals and petroleum industries, resulting in near-zero hazardous air or water pollution. This technology would also be conducive to the efficient coproduction of methane and hydrogen while also generating a relatively pure CO{sub 2} stream suitable for enhanced oil recovery (EOR) or sequestration. Specific results of bench-scale testing in the 4- to 38-lb/hr range in the EERC pilot system demonstrated high methane yields approaching 15 mol%, with high hydrogen yields approaching 50%. This was compared to an existing catalytic gasification model developed by GPE for its process. Long-term operation was demonstrated on both Powder River Basin subbituminous coal and on petcoke feedstocks utilizing oxygen injection without creating significant bed agglomeration. Carbon conversion was greater than 80% while operating at temperatures less than 1400°F, even with the shorter-than-desired reactor height. Initial designs for the GPE gasification concept called for a height that could not be accommodated by the EERC pilot facility. More gas-phase residence time should allow the syngas to be converted even more to methane. Another goal of producing significant quantities of highly concentrated catalyzed char for catalyst recovery and material handling studies was also successful. A Pd–Cu membrane was also successfully tested and demonstrated to produce 2.54 lb/day of hydrogen permeate, exceeding the desired hydrogen permeate production rate of 2.0 lb/day while being tested on actual coal-derived syngas that had been cleaned with advanced warm-gas cleanup systems. The membranes did not appear to suffer any performance degradation after exposure to the cleaned, warm syngas over a nominal 100-hour test.

  20. Linked multicontinuum and crack tensor approach for modeling of coupled geomechanics, fluid flow and transport in fractured rock

    E-Print Network [OSTI]

    Rutqvist, J.

    2014-01-01T23:59:59.000Z

    and Mining Sciences & Geomechanics Abstracts, 1983, 20:and Mining Sciences & Geomechanics Abstracts, 1985, BerrymanL W. Coupling fluid flow and geomechanics in dual-porosity

  1. Catalytic reactor

    DOE Patents [OSTI]

    Aaron, Timothy Mark (East Amherst, NY); Shah, Minish Mahendra (East Amherst, NY); Jibb, Richard John (Amherst, NY)

    2009-03-10T23:59:59.000Z

    A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

  2. Saber's heavy oil cracking refinery project

    SciTech Connect (OSTI)

    Benefield, C.S.; Glasscock, W.L.

    1983-03-01T23:59:59.000Z

    Perhaps more than any other industry, petroleum refining has been subjected to the radical swings in business and political climates of the past several decades. Because of the huge investments and long lead times to construct refining facilities, stable government policies, predictable petroleum prices, secure feedstock supplies and markets, and reliable cost estimates are necessary ingredients to effectively plan new refinery projects. However, over the past ten years the political and economic climates have provided anything but these conditions. Yet, refiners have demonstrated a willingness to undertake risks by continuing to expand and modernize their refineries. The refining business -- just as most businesses -- responds to economic incentives. These incentives, when present, result in new technology and capacity additions. In the 1940's, significant technology advances were commercialized to refine higher-octane motor gasolines. Such processes as continuous catalytic cracking (Houdry Process Corporation), fluid catalytic cracking (Standard Oil Development Company), HF alkylation (UOP and Phillips Petroleum Company), and catalytic reforming (UOP) began to supply a growing gasoline market, generated from the war effort and the ever increasing numbers of automobiles on the road. The post-war economy of the 1950's and 1960's further escalated demand for refined products, products which had to meet higher performance specifications and be produced from a wider range of raw materials. The refining industry met the challenge by introducing hydro-processing technology, such as hydrocracking developed in 1960. But, the era must be characterized by the large crude processing capacity additions, required to meet demand from the rapidly expanding U.S. economy. In 1950, refining capacity was 6.2 million BPD. By 1970, capacity had grown to 11.9 million BPD, an increase of 91%.

  3. Concentric catalytic combustor

    DOE Patents [OSTI]

    Bruck, Gerald J. (Oviedo, FL); Laster, Walter R. (Oviedo, FL)

    2009-03-24T23:59:59.000Z

    A catalytic combustor (28) includes a tubular pressure boundary element (90) having a longitudinal flow axis (e.g., 56) separating a first portion (94) of a first fluid flow (e.g., 24) from a second portion (95) of the first fluid flow. The pressure boundary element includes a wall (96) having a plurality of separate longitudinally oriented flow paths (98) annularly disposed within the wall and conducting respective portions (100, 101) of a second fluid flow (e.g., 26) therethrough. A catalytic material (32) is disposed on a surface (e.g., 102, 103) of the pressure boundary element exposed to at least one of the first and second portions of the first fluid flow.

  4. Simulation of FCC riser flow with multiphase heat transfer and cracking reactions.

    SciTech Connect (OSTI)

    Chang, S. L.; Zhou, C. Q.; Energy Systems

    2003-08-01T23:59:59.000Z

    A validated Computational Fluid Dynamics (CFD) code ICRKFLO was developed for simulations of three-dimensional three-phase reacting flows in Fluid Catalytic Cracking (FCC) riser reactors. It calculates the product yields based on local flow properties by solving the fundamental conservation principles of mass, momentum, and energy for the flow properties associated with the gas, liquid, and solid phases. Unique phenomenological models and numerical techniques were developed specifically for the FCC flow simulation. The models include a spray vaporization model, a particle-solid interaction model, and an interfacial heat transfer model. The numerical techniques include a time-integral approach to overcome numerical stiffness problems in chemical kinetics rate calculations and a hybrid hydrodynamic-kinetic treatment to facilitate detailed kinetics calculations of cracking reactions. ICRKFLO has been validated with extensive test data from two pilot and one commercial FCC units. It is proven to be useful for advanced development of FCC riser reactors.

  5. Method and apparatus for a catalytic firebox reactor

    DOE Patents [OSTI]

    Smith, Lance L. (North Haven, CT); Etemad, Shahrokh (Trumbull, CT); Ulkarim, Hasan (Hamden, CT); Castaldi, Marco J. (Bridgeport, CT); Pfefferle, William C. (Madison, CT)

    2001-01-01T23:59:59.000Z

    A catalytic firebox reactor employing an exothermic catalytic reaction channel and multiple cooling conduits for creating a partially reacted fuel/oxidant mixture. An oxidation catalyst is deposited on the walls forming the boundary between the multiple cooling conduits and the exothermic catalytic reaction channel, on the side of the walls facing the exothermic catalytic reaction channel. This configuration allows the oxidation catalyst to be backside cooled by any fluid passing through the cooling conduits. The heat of reaction is added to both the fluid in the exothermic catalytic reaction channel and the fluid passing through the cooling conduits. After discharge of the fluids from the exothermic catalytic reaction channel, the fluids mix to create a single combined flow. A further innovation in the reactor incorporates geometric changes in the exothermic catalytic reaction channel to provide streamwise variation of the velocity of the fluids in the reactor.

  6. Carbenium ion intermediates in catalytic cracking

    E-Print Network [OSTI]

    Zardkoohi, Minoo

    1987-01-01T23:59:59.000Z

    C, (d) 300 C, (e) 400 C C HNR spectra of sec-butyl chloride antimony pentafluoride mixture 16 13C NMR spectrum of C- ethene on H-ZSN5 . . . . 19 C CPNAS spectrum of tri-phenylmethyl chloride adsorbed on silica-alumina Schematic representation... &Vdk' 800 me )OO 0 - 100 -200 PPll Fig. 5 l~C CPNAS spectrum of tri-phenylmethyl chloride adsorbed on silica-alumina. 21 times, techniques which allow for moderately higher reso- lution are required. One such technique is combined cross...

  7. The complexity of catalytically "cracking" cellulose | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chain length affects oxygen's departure in key reaction for building bio-fuels Replacing fossil fuels in industrial applications could reduce economic, environmental and security...

  8. The complexity of catalytically "cracking" cellulose | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    However, transforming bio-feedstock into fuels means quickly and efficiently removing oxygen atoms. World energy consumption is predicted to grow by more than 50 percent between...

  9. Catalytic Distillation

    E-Print Network [OSTI]

    Smith, L. A., Jr.; Hearn, D.; Wynegar, D. P.

    1984-01-01T23:59:59.000Z

    Catalytic Distillation' refers to a chemical process which performs both a catalyzed reaction and primary fractionation of the reaction components simultaneously. A structured catalyst which also is an effective distillation component has been...

  10. Ashland Oil Inc. has new heavy oil cracking technology

    SciTech Connect (OSTI)

    Not Available

    1980-04-21T23:59:59.000Z

    Ashland's new ''Reduced Crude Conversion'' is a fluid catalytic cracking process that permits more efficient use of the bottoms of the crude barrel, including the production of a given amount of gasoline from 20% less crude. Gasoline yields go from 49.8% for Arabian light crudes to 56.9% for Murban crudes. The new process, details of which have not been revealed, operates at ''high'' temperatures and about 1 atm; requires no feed hydrogen (and therefore, according to Ashland, compares favorably with hydrocracking); is not inhibited by catalyst poisons such as nickel and vanadium, even though these metals might adhere to the proprietary catalyst; and probably uses a zeolite catalyst. Ashland is planning a $70 million, 40,000 bbl/day unit which is scheduled to go on stream in 1982 at its Catlettsburg, Ky., refinery.

  11. Methodology for extracting local constants from petroleum cracking flows

    DOE Patents [OSTI]

    Chang, Shen-Lin (Woodridge, IL); Lottes, Steven A. (Naperville, IL); Zhou, Chenn Q. (Munster, IN)

    2000-01-01T23:59:59.000Z

    A methodology provides for the extraction of local chemical kinetic model constants for use in a reacting flow computational fluid dynamics (CFD) computer code with chemical kinetic computations to optimize the operating conditions or design of the system, including retrofit design improvements to existing systems. The coupled CFD and kinetic computer code are used in combination with data obtained from a matrix of experimental tests to extract the kinetic constants. Local fluid dynamic effects are implicitly included in the extracted local kinetic constants for each particular application system to which the methodology is applied. The extracted local kinetic model constants work well over a fairly broad range of operating conditions for specific and complex reaction sets in specific and complex reactor systems. While disclosed in terms of use in a Fluid Catalytic Cracking (FCC) riser, the inventive methodology has application in virtually any reaction set to extract constants for any particular application and reaction set formulation. The methodology includes the step of: (1) selecting the test data sets for various conditions; (2) establishing the general trend of the parametric effect on the measured product yields; (3) calculating product yields for the selected test conditions using coupled computational fluid dynamics and chemical kinetics; (4) adjusting the local kinetic constants to match calculated product yields with experimental data; and (5) validating the determined set of local kinetic constants by comparing the calculated results with experimental data from additional test runs at different operating conditions.

  12. Methods of cracking a crude product to produce additional crude products

    DOE Patents [OSTI]

    Mo, Weijian (Sugar Land, TX); Roes, Augustinus Wilhelmus Maria (Houston, TX); Nair, Vijay (Katy, TX)

    2009-09-08T23:59:59.000Z

    A method for producing a crude product is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce one or more crude products. At least one of the crude products has a boiling range distribution from 38.degree. C. and 343.degree. C. as determined by ASTM Method D5307. The crude product having the boiling range distribution from 38.degree. C. and 343.degree. C. is catalytically cracked to produce one or more additional crude products. At least one of the additional crude products is a second gas stream. The second gas stream has a boiling point of at most 38.degree. C. at 0.101 MPa.

  13. CATALYTIC BIOMASS LIQUEFACTION

    E-Print Network [OSTI]

    Ergun, Sabri

    2013-01-01T23:59:59.000Z

    LBL-11 019 UC-61 CATALYTIC BIOMASS LIQUEFACTION Sabri Ergun,Catalytic Liquefaction of Biomass,n M, Seth, R. Djafar, G.of California. CATALYTIC BIOMASS LIQUEFACTION QUARTERLY

  14. Piloted rich-catalytic lean-burn hybrid combustor

    DOE Patents [OSTI]

    Newburry, Donald Maurice (Orlando, FL)

    2002-01-01T23:59:59.000Z

    A catalytic combustor assembly which includes, an air source, a fuel delivery means, a catalytic reactor assembly, a mixing chamber, and a means for igniting a fuel/air mixture. The catalytic reactor assembly is in fluid communication with the air source and fuel delivery means and has a fuel/air plenum which is coated with a catalytic material. The fuel/air plenum has cooling air conduits passing therethrough which have an upstream end. The upstream end of the cooling conduits is in fluid communication with the air source but not the fuel delivery means.

  15. Catalytic Coherence

    E-Print Network [OSTI]

    Johan Aberg

    2014-10-20T23:59:59.000Z

    Due to conservation of energy we cannot directly turn a quantum system with a definite energy into a superposition of different energies. However, if we have access to an additional resource in terms of a system with a high degree of coherence, as for standard models of laser light, we can overcome this limitation. The question is to what extent coherence gets degraded when utilized. Here it is shown that coherence can be turned into a catalyst, meaning that we can use it repeatedly without ever diminishing its power to enable coherent operations. This finding stands in contrast to the degradation of other quantum resources, and has direct consequences for quantum thermodynamics, as it shows that latent energy that may be locked into superpositions of energy eigenstates can be released catalytically.

  16. CATALYTIC LIQUEFACTION OF BIOMASS

    E-Print Network [OSTI]

    Seth, Manu

    2012-01-01T23:59:59.000Z

    liquid Fuels from Biomass: "Catalyst Screening and KineticUC-61 (l, RCO osn CDL or BIOMASS CATALYTIC LIQUEFACTION ManuCATALYTIC LIQUEFACTION OF BIOMASS Manu Seth, Roger Djafar,

  17. CATALYTIC BIOMASS LIQUEFACTION

    E-Print Network [OSTI]

    Ergun, Sabri

    2013-01-01T23:59:59.000Z

    Solvent Systems Catalystic Biomass Liquefaction Investigatereactor Product collection Biomass liquefaction process12-13, 1980 CATALYTIC BIOMASS LIQUEFACTION Sabri Ergun,

  18. Hydrocarbon cracking with yttrium exchanged zeolite y catalyst

    SciTech Connect (OSTI)

    Lochow, C.F.; Kovacs, D.B.

    1987-05-12T23:59:59.000Z

    A process is described for cracking a gas oil boiling range hydrocarbon feedstock comprising the step of contacting the feedstock in a catalytic cracking zone under catalytic cracking conditions to produce convulsion products comprising gasoline with a catalyst composition. The process comprises: a Y crystalline aluminosilicate zeolite, having the structure of faujasite and having uniform pore diameters and a silica to alumina mole ratio of at least about 5; an inorganic oxide matrix; and the zeolite having been ion exchanged with a mixture of rare earths prior to compositing with the matrix; and the zeolite having been subsequently further ion exchanged with yttrium following compositing with the matrix, whereby the catalyst composition contains 0.30 to 3.0 wt% yttrium.

  19. Crack coalescence in granite

    E-Print Network [OSTI]

    Miller, James Thomas, Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    This thesis experimentally investigates crack coalescence in prismatic Barre Granite specimens with two pre-cut, open flaws under uniaxial compression. Using a high-speed video system, crack initiation, propagation, and ...

  20. Novel Fast Pyrolysis/Catalytic Technology for the Production of Stable Upgraded Liquids

    SciTech Connect (OSTI)

    Ted Oyama, Foster Agblevor, Francine Battaglia, Michael Klein

    2013-01-18T23:59:59.000Z

    The objective of the proposed research is the demonstration and development of a novel biomass pyrolysis technology for the production of a stable bio-oil. The approach is to carry out catalytic hydrodeoxygenation (HDO) and upgrading together with pyrolysis in a single fluidized bed reactor with a unique two-level design that permits the physical separation of the two processes. The hydrogen required for the HDO will be generated in the catalytic section by the water-gas shift reaction employing recycled CO produced from the pyrolysis reaction itself. Thus, the use of a reactive recycle stream is another innovation in this technology. The catalysts will be designed in collaboration with BASF Catalysts LLC (formerly Engelhard Corporation), a leader in the manufacture of attrition-resistant cracking catalysts. The proposed work will include reactor modeling with state-of-the-art computational fluid dynamics in a supercomputer, and advanced kinetic analysis for optimization of bio-oil production. The stability of the bio-oil will be determined by viscosity, oxygen content, and acidity determinations in real and accelerated measurements. A multi-faceted team has been assembled to handle laboratory demonstration studies and computational analysis for optimization and scaleup.

  1. Rich catalytic injection

    DOE Patents [OSTI]

    Veninger, Albert (Coventry, CT)

    2008-12-30T23:59:59.000Z

    A gas turbine engine includes a compressor, a rich catalytic injector, a combustor, and a turbine. The rich catalytic injector includes a rich catalytic device, a mixing zone, and an injection assembly. The injection assembly provides an interface between the mixing zone and the combustor. The injection assembly can inject diffusion fuel into the combustor, provides flame aerodynamic stabilization in the combustor, and may include an ignition device.

  2. Performance characterization of a hydrogen catalytic heater.

    SciTech Connect (OSTI)

    Johnson, Terry Alan; Kanouff, Michael P.

    2010-04-01T23:59:59.000Z

    This report describes the performance of a high efficiency, compact heater that uses the catalytic oxidation of hydrogen to provide heat to the GM Hydrogen Storage Demonstration System. The heater was designed to transfer up to 30 kW of heat from the catalytic reaction to a circulating heat transfer fluid. The fluid then transfers the heat to one or more of the four hydrogen storage modules that make up the Demonstration System to drive off the chemically bound hydrogen. The heater consists of three main parts: (1) the reactor, (2) the gas heat recuperator, and (3) oil and gas flow distribution manifolds. The reactor and recuperator are integrated, compact, finned-plate heat exchangers to maximize heat transfer efficiency and minimize mass and volume. Detailed, three-dimensional, multi-physics computational models were used to design and optimize the system. At full power the heater was able to catalytically combust a 10% hydrogen/air mixture flowing at over 80 cubic feet per minute and transfer 30 kW of heat to a 30 gallon per minute flow of oil over a temperature range from 100 C to 220 C. The total efficiency of the catalytic heater, defined as the heat transferred to the oil divided by the inlet hydrogen chemical energy, was characterized and methods for improvement were investigated.

  3. Catalytic distillation structure

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A. (Bellaire, TX)

    1984-01-01T23:59:59.000Z

    Catalytic distillation structure for use in reaction distillation columns, a providing reaction sites and distillation structure and consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and being present with the catalyst component in an amount such that the catalytic distillation structure consist of at least 10 volume % open space.

  4. Fluidic Catalytic Cracking Power Recovery Dynamic Computer Simulation

    E-Print Network [OSTI]

    Samurin, N. A.

    1980-01-01T23:59:59.000Z

    operation of the primary mechanical components, specifically the axial compressor and hot gas expander. The present work expands upon the steady state model to add the dynamic characteristics of these elements as well as the effects of the controlling...

  5. Cracking blends of gas oil and residual oil

    SciTech Connect (OSTI)

    Myers, G.D.

    1988-03-01T23:59:59.000Z

    In a catalytic cracking process unit wherein a gas oil feed is cracked in a cracking zone at an elevated temperature in the presence of a cracking catalyst, the cracking catalyst is regenerated in a regeneration zone by burning coke of the catalyst, and catalyst is circulated between the cracking zone and the regeneration zone. The improvement is described for obtaining a naphtha product of improved octane number comprising introducing sufficient of a nickel and vanadium metals-containing heavy feedstock with the gas oil feed introduced into the cracking zone to deposit nickel and vanadium metals on the catalyst and raise the nickel and metals-content of the catalyst to a level ranging from about 1500 to about 6000 parts per million of the metals expressed as equivalent nickel, based on the weight of the catalyst, and maintaining the nickel and vanadium metals level on the catalyst by withdrawing high nickel and vanadium metals containing catalyst and adding low nickel and vanadium metals-containing catalyst to the regeneration zone.

  6. Sequential tasks performed by catalytic pumps for colloidal crystallization

    E-Print Network [OSTI]

    Ali Afshar Farniya; Maria J. Esplandiu; Adrian Bachtold

    2014-10-20T23:59:59.000Z

    Gold-platinum catalytic pumps immersed in a chemical fuel are used to manipulate silica colloids. The manipulation relies on the electric field and the fluid flow generated by the pump. Catalytic pumps perform various tasks, such as the repulsion of colloids, the attraction of colloids, and the guided crystallization of colloids. We demonstrate that catalytic pumps can execute these tasks sequentially over time. Switching from one task to the next is related to the local change of the proton concentration, which modifies the colloid zeta potential and consequently the electric force acting on the colloids.

  7. Selective dehydrogenation of propane over novel catalytic materials

    SciTech Connect (OSTI)

    Sault, A.G.; Boespflug, E.P.; Martino, A.; Kawola, J.S.

    1998-02-01T23:59:59.000Z

    The conversion of small alkanes into alkenes represents an important chemical processing area; ethylene and propylene are the two most important organic chemicals manufactured in the U.S. These chemicals are currently manufactured by steam cracking of ethane and propane, an extremely energy intensive, nonselective process. The development of catalytic technologies (e.g., selective dehydrogenation) that can be used to produce ethylene and propylene from ethane and propane with greater selectivity and lower energy consumption than steam cracking will have a major impact on the chemical processing industry. This report details a study of two novel catalytic materials for the selective dehydrogenation of propane: Cr supported on hydrous titanium oxide ion-exchangers, and Pt nanoparticles encapsulated in silica and alumina aerogel and xerogel matrices.

  8. Development of crack shape: LBB methodology for cracked pipes

    SciTech Connect (OSTI)

    Moulin, D.; Chapuliot, S.; Drubay, B. [Commissariat a l Energie Atomique, Gif sur Yvette (France)

    1997-04-01T23:59:59.000Z

    For structures like vessels or pipes containing a fluid, the Leak-Before-Break (LBB) assessment requires to demonstrate that it is possible, during the lifetime of the component, to detect a rate of leakage due to a possible defect, the growth of which would result in a leak before-break of the component. This LBB assessment could be an important contribution to the overall structural integrity argument for many components. The aim of this paper is to review some practices used for LBB assessment and to describe how some new R & D results have been used to provide a simplified approach of fracture mechanics analysis and especially the evaluation of crack shape and size during the lifetime of the component.

  9. Catalytic distillation process

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A. (Bellaire, TX)

    1982-01-01T23:59:59.000Z

    A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  10. Catalytic distillation process

    DOE Patents [OSTI]

    Smith, L.A. Jr.

    1982-06-22T23:59:59.000Z

    A method is described for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C[sub 4] feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  11. Catalytic distillation structure

    DOE Patents [OSTI]

    Smith, L.A. Jr.

    1984-04-17T23:59:59.000Z

    Catalytic distillation structure is described for use in reaction distillation columns, and provides reaction sites and distillation structure consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and is present with the catalyst component in an amount such that the catalytic distillation structure consists of at least 10 volume % open space. 10 figs.

  12. Automated pavement crack detection

    E-Print Network [OSTI]

    Rao, Ashok Madhava

    1991-01-01T23:59:59.000Z

    : Electrical Engineering AUTOMATED PAVEMENT CRACK DETECTION A Thesis by ASHOK MADHAVA RAO Approved as to style and content by . c Norman C. Grisw d (Chair of Committ ) Nasser Kehtarnavaz (Member) g, J~, Karan Watson Robert L. Lytt (Member) Jo W.... Howze (Head of Department) December 1991 111 ABSTRACT Automated Pavement Crack Detection. (December 1991) Ashok Madhava, Rao, B. E. , Mysore University Chair of Advisory Committee: Norman. C. Griswold Due to load, environmental and structural...

  13. Catalytic nanoporous membranes

    DOE Patents [OSTI]

    Pellin, Michael J; Hryn, John N; Elam, Jeffrey W

    2013-08-27T23:59:59.000Z

    A nanoporous catalytic membrane which displays several unique features Including pores which can go through the entire thickness of the membrane. The membrane has a higher catalytic and product selectivity than conventional catalysts. Anodic aluminum oxide (AAO) membranes serve as the catalyst substrate. This substrate is then subjected to Atomic Layer Deposition (ALD), which allows the controlled narrowing of the pores from 40 nm to 10 nm in the substrate by deposition of a preparatory material. Subsequent deposition of a catalytic layer on the inner surfaces of the pores reduces pore sizes to less than 10 nm and allows for a higher degree of reaction selectivity. The small pore sizes allow control over which molecules enter the pores, and the flow-through feature can allow for partial oxidation of reactant species as opposed to complete oxidation. A nanoporous separation membrane, produced by ALD is also provided for use in gaseous and liquid separations. The membrane has a high flow rate of material with 100% selectivity. Also provided is a method for producing a catalytic membrane having flow-through pores and discreet catalytic clusters adhering to the inside surfaces of the pores.

  14. Steam reformer with catalytic combustor

    DOE Patents [OSTI]

    Voecks, Gerald E. (La Crescenta, CA)

    1990-03-20T23:59:59.000Z

    A steam reformer is disclosed having an annular steam reforming catalyst bed formed by concentric cylinders and having a catalytic combustor located at the center of the innermost cylinder. Fuel is fed into the interior of the catalytic combustor and air is directed at the top of the combustor, creating a catalytic reaction which provides sufficient heat so as to maintain the catalytic reaction in the steam reforming catalyst bed. Alternatively, air is fed into the interior of the catalytic combustor and a fuel mixture is directed at the top. The catalytic combustor provides enhanced radiant and convective heat transfer to the reformer catalyst bed.

  15. A Photosynthetic Hydrogel for Catalytic Hydrogen Production ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Photosynthetic Hydrogel for Catalytic Hydrogen Production Home > Research > ANSER Research Highlights > A Photosynthetic Hydrogel for Catalytic Hydrogen Production...

  16. Catalytic coal liquefaction process

    DOE Patents [OSTI]

    Garg, D.; Sunder, S.

    1986-12-02T23:59:59.000Z

    An improved process for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a solvent comprises using as catalyst a mixture of a 1,2- or 1,4-quinone and an alkaline compound, selected from ammonium, alkali metal, and alkaline earth metal oxides, hydroxides or salts of weak acids. 1 fig.

  17. Crack healing as a function of pOH- and fracture morphology

    E-Print Network [OSTI]

    Fallon, Jessica Anne

    2005-02-17T23:59:59.000Z

    Crack healing in quartz has been investigated by optical microscopy and interferometry of rhombohedral ( 1) cracks in polished Brazilian quartz prisms that were annealed hydrothermally at temperatures of 250?C and 400?C for 2.4 to 240 hours, fluid... pressure Pf = Pc = 41 MPa, and varying pOH- (from 5.4 to 1.2 at 250?C for fluids consisting of distilled water and NaOH solutions with molalities up to 1). Crack morphologies before and after annealing were recorded for each sample in plane light...

  18. Hydrocarbon cracking catalyst

    SciTech Connect (OSTI)

    Lochow, C.F.; Kovacs, D.B.

    1988-12-27T23:59:59.000Z

    This patent describes a catalyst composition for cracking hydrocarbons to maximize gasoline comprising: rare earth exchanged ''Y'' crystalline faujasite dispersed in a clay containing matrix material; and which has been subsequently further ion exchanged to contain 0.20 to 3.0 wt% yttrium, calculated as the oxide, whereby the yttrium is chemically combined in the catalyst composition.

  19. Development of reduced crude cracking catalysts

    SciTech Connect (OSTI)

    Hettinger, W.P. Jr. (Ashland Petroleum Company, KY (USA))

    1987-08-01T23:59:59.000Z

    In 1974 OPEC imposed an embargo on oil to the United States and caused a rapid rise in the price of a barrel of oil. At the time of the embargo, Ashland imported a considerable portion of its oil from the Middle East, thus raising the question of oil availability. As the problem increased in severity, Messrs. George Meyer, Oliver Zandona and Llyod Busch, began to explore alternative ways of squeezing more product from a given barrel of crude. After considering many alternatives, they arrived at the innovative thought that it might be possible to catalytically crack the 1050{degree}F plus fraction of the barrel directly to gasoline which would in effect, give them an additional volume of crude oil. Also, if vacuum fractionation were eliminated and if the entire 650{degree}F plus (reduced crude) portion of the barrel processed, this would further reduce operating costs. With these objectives and some new process innovations in mind, they began reduced crude cracking experimentation in a small 12,000 B/D FCC operating unit at Louisville. It was from these goals, concepts and a small operating unit, that the RCC process was born.

  20. Catalytic thermal barrier coatings

    DOE Patents [OSTI]

    Kulkarni, Anand A. (Orlando, FL); Campbell, Christian X. (Orlando, FL); Subramanian, Ramesh (Oviedo, FL)

    2009-06-02T23:59:59.000Z

    A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

  1. Catalytic hydrodesulfurization of bitumen

    SciTech Connect (OSTI)

    Sharma, R.K.; Olson, E.S. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-31T23:59:59.000Z

    Investigations of the catalytic hydrodesulfurization of Venezuela bitumen and its water emulsion (Orimulsion) were carried out. This material contained a large amount of sulfur and organometallics, such as vanadium and nickel compounds. A variety of nickel and molybdenum catalysts were prepared. These, as well as two commercial catalysts, were tested with Orimulsion and vacuum-dried, pentane-insoluble and soluble bitumen. Catalytic hydrotreatment removed up to 75% of sulfur from the bitumen. Hydrodesulfurization was found to be affected by reaction temperature, reaction time, catalyst, and feed material. Moisture-free bitumen and a pentane-soluble bitumen fraction were desulfurized more effectively than Orimulsion. Zeolite-based catalysts gave higher desulfurization than synthetic clay catalysts.

  2. Catalytic reforming catalyst

    SciTech Connect (OSTI)

    Buss, W.C.; Kluksdahl, H.E.

    1980-12-09T23:59:59.000Z

    An improved catalyst, having a reduced fouling rate when used in a catalytic reforming process, said catalyst comprising platinum disposed on an alumina support wherein the alumina support is obtained by removing water from aluminum hydroxide produced as a by-product from a ziegler higher alcohol synthesis reaction, and wherein the alumina is calcined at a temperature of 1100-1400/sup 0/F so as to have a surface area of 165 to 215 square meters per gram.

  3. Catalytic reactor for low-Btu fuels

    DOE Patents [OSTI]

    Smith, Lance (North Haven, CT); Etemad, Shahrokh (Trumbull, CT); Karim, Hasan (Simpsonville, SC); Pfefferle, William C. (Madison, CT)

    2009-04-21T23:59:59.000Z

    An improved catalytic reactor includes a housing having a plate positioned therein defining a first zone and a second zone, and a plurality of conduits fabricated from a heat conducting material and adapted for conducting a fluid therethrough. The conduits are positioned within the housing such that the conduit exterior surfaces and the housing interior surface within the second zone define a first flow path while the conduit interior surfaces define a second flow path through the second zone and not in fluid communication with the first flow path. The conduit exits define a second flow path exit, the conduit exits and the first flow path exit being proximately located and interspersed. The conduits define at least one expanded section that contacts adjacent conduits thereby spacing the conduits within the second zone and forming first flow path exit flow orifices having an aggregate exit area greater than a defined percent of the housing exit plane area. Lastly, at least a portion of the first flow path defines a catalytically active surface.

  4. Catalytic reforming methods

    DOE Patents [OSTI]

    Tadd, Andrew R; Schwank, Johannes

    2013-05-14T23:59:59.000Z

    A catalytic reforming method is disclosed herein. The method includes sequentially supplying a plurality of feedstocks of variable compositions to a reformer. The method further includes adding a respective predetermined co-reactant to each of the plurality of feedstocks to obtain a substantially constant output from the reformer for the plurality of feedstocks. The respective predetermined co-reactant is based on a C/H/O atomic composition for a respective one of the plurality of feedstocks and a predetermined C/H/O atomic composition for the substantially constant output.

  5. Catalytic hydrodesulfurization of bitumen

    SciTech Connect (OSTI)

    Sharma, R.K.; Olson, E.S. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-31T23:59:59.000Z

    Investigations of the catalytic hydrodesulfurization of Venezuela bitumen and its water-emulsion (Orimulsion) were carried out. A variety of catalysts were prepared and some impregnated with molybdenum and sulfided. These and two commercial catalysts were tested with Orimulsion, vacuum-dried Orimulsion, and pentane-insoluble and soluble Orimulsion. Hydrotreatment of feed material was done in a 15-mL tube reactor using a variety of catalysts at 390{degrees}C under an initial 1000-psi hydrogen pressure with a reaction time of 1-3 hours. The hydrotreated products were analyzed by total sulfur analysis. Catalytic hydrotreatment removed up to 75% of sulfur from the bitumen. Nickel and/or molybdenum impregnation on various supports promoted sulfur removal from Orimulsion. Hydrodesulfurization was found to be affected by reaction temperature, reaction time, catalyst, and feed material. A moisture-free bitumen and a pentane-soluble bitumen fraction were desulfurized more effectively than Orimulsion. Zeolite-based catalysts gave higher desulfurization than synthetic clay catalysts or commercial AMOCAT and HDN catalysts.

  6. Novel Catalytic Membrane Reactors

    SciTech Connect (OSTI)

    Stuart Nemser, PhD

    2010-10-01T23:59:59.000Z

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  7. Crack Path Selection Fatigue crack path imaged via SEM

    E-Print Network [OSTI]

    Rollins, Andrew M.

    Crack path selects secondary phases and interface Conclusions ·Nb-Si Alloys tested exhibited toughness phases fail in a brittle manner Fatigue Crack Growth ABSTRACT Advanced aerospace materials continue at high temperatures. An important property of any high temperature aerospace engineering material is its

  8. Bifunctional Catalysts for the Selective Catalytic Reduction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Publications Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as Reductants...

  9. Methods and apparatus for catalytic hydrothermal gasification...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Methods and apparatus for catalytic hydrothermal gasification of biomass Re-direct Destination: Continuous processing of wet biomass feedstock by catalytic hydrothermal...

  10. Synthesis, Characterization, and Catalytic Function of Novel...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Characterization, and Catalytic Function of Novel Highly Dispersed Tungsten Oxide Catalysts on Mesoporous Silica . Synthesis, Characterization, and Catalytic Function of Novel...

  11. Preparation, Characterization, and Catalytic Properties of Tungsten...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Preparation, Characterization, and Catalytic Properties of Tungsten Trioxide Cyclic Trimers on FeO(111)Pt(111). Preparation, Characterization, and Catalytic Properties of Tungsten...

  12. Stress corrosion crack growth in porous sandstones. 

    E-Print Network [OSTI]

    Ojala, Ira O

    Stress corrosion crack growth occurs when the chemical weakening of strained crack tip bonds facilitates crack propagation. I have examined the effect of chemical processes on the growth of a creack population by carrying out triaxial compression...

  13. The catalytic oxidation of propane 

    E-Print Network [OSTI]

    Sanderson, Charles Frederick

    1949-01-01T23:59:59.000Z

    THE CATALYTIC OXIDATION OP PROPANE A Thesis By Charles Frederick Sandersont * * June 1949 Approval as to style and content recommended: Head of the Department of Chemical Engineering THE CATALYTICi OXIDATTON OF PROPANE A Thesis By Charles... Frederick ;Sandersonit * June 1949 THE CATALYTIC OXIDATION OP PROPANE A Thesis Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

  14. The catalytic oxidation of propane

    E-Print Network [OSTI]

    Sanderson, Charles Frederick

    1949-01-01T23:59:59.000Z

    THE CATALYTIC OXIDATION OP PROPANE A Thesis By Charles Frederick Sandersont * * June 1949 Approval as to style and content recommended: Head of the Department of Chemical Engineering THE CATALYTICi OXIDATTON OF PROPANE A Thesis By Charles... Frederick ;Sandersonit * June 1949 THE CATALYTIC OXIDATION OP PROPANE A Thesis Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

  15. Peridynamic model for fatigue cracking.

    SciTech Connect (OSTI)

    Silling, Stewart A.; Abe Askari (Boeing)

    2014-10-01T23:59:59.000Z

    The peridynamic theory is an extension of traditional solid mechanics in which the field equations can be applied on discontinuities, such as growing cracks. This paper proposes a bond damage model within peridynamics to treat the nucleation and growth of cracks due to cyclic loading. Bond damage occurs according to the evolution of a variable called the %22remaining life%22 of each bond that changes over time according to the cyclic strain in the bond. It is shown that the model reproduces the main features of S-N data for typical materials and also reproduces the Paris law for fatigue crack growth. Extensions of the model account for the effects of loading spectrum, fatigue limit, and variable load ratio. A three-dimensional example illustrates the nucleation and growth of a helical fatigue crack in the torsion of an aluminum alloy rod.

  16. Progressive flow cracking of coal/oil mixtures with high metals content catalyst

    SciTech Connect (OSTI)

    Zandona, O.J.

    1989-10-10T23:59:59.000Z

    This patent describes a process for economically producing liquid fuel products at least partly from coal. It comprises: introducing a progressive flow catalytic cracking zone a charge stock comprising a pumpable mixture of solid, particulate coal and carbo-metallic oil and forming within the zone a stream having a linear velocity of at least about 25 feet per second. The stream comprising the charge stock and a hydrocarbon zeolite cracking catalyst promoting dehydrogenation of the charge stock; forming mobile hydrogen within the zone by the dehydrogenation; introducing the mobile hydrogen into the stream by dehydrogenation of the charge stock in the absence of added molecular hydrogen, thereby producing liquid products from the charge stock while laying down coke on the hydrocarbon cracking catalyst in the range of about 0.3% to about 3% and thereby producing spent catalyst; separating from the spent catalyst the liquid products.

  17. Catastrophic Cracking Courtesy of Quiescent Cavitation

    E-Print Network [OSTI]

    Daily, D Jesse; Thomson, Scott L; Truscott, Tadd T

    2012-01-01T23:59:59.000Z

    A popular party trick is to fill a glass bottle with water and hit the top of the bottle with an open hand, causing the bottom of the bottle to break open. We investigate the source of the catastrophic cracking through the use of high-speed video and an accelerometer attached to the bottom of a glass bottle. Upon closer inspection, it is obvious that the acceleration caused by hitting the top of the bottle is followed by the formation of bubbles near the bottom. The nearly instantaneous acceleration creates an area of low pressure on the bottom of the bottle where cavitation bubbles form. Moments later, the cavitation bubbles collapse at roughly 10 times the speed of formation, causing the bottle to break. The accelerometer data shows that the bottle is broken after the bubbles collapse and that the magnitude of the bubble collapse is greater than the initial impact. The fluid dynamics video highlights that this trick will not work if the bottle is empty nor if it is filled with a carbonated fluid because the...

  18. Parallel interacting edge cracks under pure bending

    E-Print Network [OSTI]

    Moran, Ivan

    1991-01-01T23:59:59.000Z

    specimens. . . 66 Table 6. 4 a SIFs for interactive cracks. Position 14. . 73 Table 6. 4 b SIFs for interactive cracks. Position 24 . . 79 Table 6. 4 c SIFs for interactive cracks. Position 13. . 83 Table 6. 5 a K~ff for position 14 Table 6. 5 b K... Table 5. 3 Models Dimensions SPECIMEN MODEL 1 MODEL 2 Length L (inches) Dimension m (in) 6. 50 6. 50 1. 25 1. 25 Spec. Width H (in) 1. 100 1. 276 Thickness t (in) 0. 238 0. 238 Crack Angle p (o) 90 54 Crack Width c (in) Crack Length a (in) 0...

  19. Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor

    SciTech Connect (OSTI)

    Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others

    1997-04-01T23:59:59.000Z

    Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

  20. INTEGRAL CATALYTIC COMBUSTION/FUEL REFORMING

    E-Print Network [OSTI]

    INTEGRAL CATALYTIC COMBUSTION/FUEL REFORMING FOR GAS TURBINE Prepared For: California Energy REPORT (FAR) INTEGRAL CATALYTIC COMBUSTION/FUEL REFORMING FOR GAS TURBINE CYCLES EISG AWARDEE University://www.energy.ca.gov/research/index.html. #12;Page 1 Integral Catalytic Combustion/Fuel Reforming for Gas Turbine Cycles EISG Grant # 99

  1. Cracking of simulated oil refinery off-gas over a coal char, petroleum coke, and quartz

    SciTech Connect (OSTI)

    Yuan Zhang; Jin-hu Wu; Dong-ke Zhang [Chinese Academy of Sciences, Taiyuan (China). Institute of Coal Chemistry

    2008-03-15T23:59:59.000Z

    The cracking of oil refinery off-gas, simulated with a gas mixture containing methane (51%), ethylene (21.4%), ethane (21.1%), and propane (6.5%), over a coal char, petroleum coke, and quartz, respectively, has been studied in a fixed bed reactor. The experiments were performed at temperatures between 850 and 1000{sup o}C and at atmospheric pressure. The results show that the conversions of all species considered increased with increasing temperature. Ethane and propane completely decomposed over all three bed materials in the temperature range investigated. However, the higher initial conversion rates of methane and ethylene cracking at all temperatures were observed only over the coal char and not on the petroleum coke and quartz, indicating a significant catalytic effect of the coal char on methane and ethylene cracking. Methane and ethylene conversions decreased with reaction time due to deactivation of the coal char by carbon deposition on the char surface and, in the later stage of a cracking experiment, became negative, suggesting that methane and ethylene had been formed during the cracking of ethane and propane. 16 refs., 13 figs., 2 tabs.

  2. Nonlinear structural crack growth monitoring

    DOE Patents [OSTI]

    Welch, Donald E. (Oak Ridge, TN); Hively, Lee M. (Philadelphia, TN); Holdaway, Ray F. (Clinton, TN)

    2002-01-01T23:59:59.000Z

    A method and apparatus are provided for the detection, through nonlinear manipulation of data, of an indicator of imminent failure due to crack growth in structural elements. The method is a process of determining energy consumption due to crack growth and correlating the energy consumption with physical phenomena indicative of a failure event. The apparatus includes sensors for sensing physical data factors, processors or the like for computing a relationship between the physical data factors and phenomena indicative of the failure event, and apparatus for providing notification of the characteristics and extent of such phenomena.

  3. CrackTree: Automatic crack detection from pavement images Qin Zou a,b,c,

    E-Print Network [OSTI]

    Wang, Song

    CrackTree: Automatic crack detection from pavement images Qin Zou a,b,c, , Yu Cao c , Qingquan Li b t Pavement cracks are important information for evaluating the road condition and conducting the neces- sary pavement images. In practice, crack detection is a very challenging problem because of (1) low con- trast

  4. Original article Stem cracks in Norway spruce

    E-Print Network [OSTI]

    Boyer, Edmond

    Original article Stem cracks in Norway spruce in southern Scandinavia: causes and consequences Garpenberg, Sweden (Received 1st September 1992; accepted 17 June 1993) Summary — Stem cracks in Norway;INTRODUCTION Background During this century, the widespread crack- ing of Norway spruce (Picea abies L Karst

  5. Cracking Resistance of Asphalt Rubber Mix Versus

    E-Print Network [OSTI]

    Mobasher, Barzin

    . crack length curve for KR #12;Load vs. CMOD 0.0 0.5 1.0 1.5 2.0 Crack mouth opening, mm 0 500 1000 1500 non-linear fracture mechanics ·Compliance approach ·R-Curve approach #12;Conventional Fatigue Testing factor R-Curve approach Resistance to initiation & growth of cracks Evaluates fracture toughness

  6. Environmentally assisted cracking of LWR materials

    SciTech Connect (OSTI)

    Chopra, O.K.; Chung, H.M.; Kassner, T.F.; Shack, W.J.

    1995-12-01T23:59:59.000Z

    Research on environmentally assisted cracking (EAC) of light water reactor materials has focused on (a) fatigue initiation in pressure vessel and piping steels, (b) crack growth in cast duplex and austenitic stainless steels (SSs), (c) irradiation-assisted stress corrosion cracking (IASCC) of austenitic SSs, and (d) EAC in high- nickel alloys. The effect of strain rate during different portions of the loading cycle on fatigue life of carbon and low-alloy steels in 289{degree}C water was determined. Crack growth studies on wrought and cast SSs have been completed. The effect of dissolved-oxygen concentration in high-purity water on IASCC of irradiated Type 304 SS was investigated and trace elements in the steel that increase susceptibility to intergranular cracking were identified. Preliminary results were obtained on crack growth rates of high-nickel alloys in water that contains a wide range of dissolved oxygen and hydrogen concentrations at 289 and 320{degree}C. The program on Environmentally Assisted Cracking of Light Water Reactor Materials is currently focused on four tasks: fatigue initiation in pressure vessel and piping steels, fatigue and environmentally assisted crack growth in cast duplex and austenitic SS, irradiation-assisted stress corrosion cracking of austenitic SSs, and environmentally assisted crack growth in high-nickel alloys. Measurements of corrosion-fatigue crack growth rates (CGRs) of wrought and cast stainless steels has been essentially completed. Recent progress in these areas is outlined in the following sections.

  7. Correlating Spatial Heterogeneities in Porosity and Permeability...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fluid catalytic cracking (FCC) is a refining process for converting large andor heavy molecules of oil feedstock into smaller and lighter hydrocarbons such as gasoline....

  8. Microsoft Word - MappingMetals bh

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fluid catalytic cracking (FCC) is the refining process for converting large andor heavy molecules of oil feedstock into smaller and lighter hydrocarbons, such as gasoline....

  9. Mapping Metals Incorporation of a Single Catalyst Particle Using...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2015 Fluid catalytic cracking (FCC) is the refining process for converting large andor heavy molecules of oil feedstock into smaller and lighter hydrocarbons, such as gasoline....

  10. Bifunctional Catalysts for the Selective Catalytic Reduction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    as Reductants Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Development of Optimal Catalyst Designs and Operating Strategies for Lean NOx...

  11. Plasma-assisted catalytic reduction system

    DOE Patents [OSTI]

    Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

    1998-01-27T23:59:59.000Z

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

  12. Superconducting Cuprates on Catalytic Substrates - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transmission Electricity Transmission Find More Like This Return to Search Superconducting Cuprates on Catalytic Substrates Brookhaven National Laboratory Contact BNL About...

  13. Catalytic membranes for fuel cells

    DOE Patents [OSTI]

    Liu, Di-Jia (Naperville, IL); Yang, Junbing (Bolingbrook, IL); Wang, Xiaoping (Naperville, IL)

    2011-04-19T23:59:59.000Z

    A fuel cell of the present invention comprises a cathode and an anode, one or both of the anode and the cathode including a catalyst comprising a bundle of longitudinally aligned graphitic carbon nanotubes including a catalytically active transition metal incorporated longitudinally and atomically distributed throughout the graphitic carbon walls of said nanotubes. The nanotubes also include nitrogen atoms and/or ions chemically bonded to the graphitic carbon and to the transition metal. Preferably, the transition metal comprises at least one metal selected from the group consisting of Fe, Co, Ni, Mn, and Cr.

  14. Catalytic Nanostructures | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z C o . C lKieling ,CatalysisPortalCatalytic

  15. Characterization of cracking restraint at sawcut joints using the German Cracking Frame

    E-Print Network [OSTI]

    Vepakomma, Shilpa

    2002-01-01T23:59:59.000Z

    Cracking of concrete slabs at sawcut notches is a major concern in the early stages of construction. Several factors affecting crack initiation are material strength parameters, method and quality of curing, slab/subbase stiffness, and concrete...

  16. Characterization of geothermal reservoir crack patterns using...

    Open Energy Info (EERE)

    reservoir crack patterns using shear-wave splitting Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Characterization of geothermal reservoir...

  17. Slow crack growth in polycarbonate films

    E-Print Network [OSTI]

    Cortet, Pierre-Philippe; Vanel, Loic; Ciliberto, Sergio

    2005-01-01T23:59:59.000Z

    We study experimentally the slow growth of a single crack in polycarbonate films submitted to uniaxial and constant imposed stress. The specificity of fracture in polycarbonate films is the appearance of flame shaped macroscopic process zones at the tips of the crack. Supported by an experimental study of the mechanical properties of polycarbonate films, an analysis of the stress dependence of the mean ratio between the process zone and crack lengths, during the crack growth, show a quantitative agreement with the Dugdale-Barenblatt model of the plastic process zone. We find that the fracture growth curves obey strong scaling properties that lead to a well defined growth master curve.

  18. White Etching Cracks | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Etching Cracks Presented by Walter Holweger of Schaeffler at the Wind Turbine Tribology Seminar 2014. NREL Chicago291014Holweger26nosec...

  19. 7. Low temperature cracking in HMA Pavement Cracking Al-Qadi, Scarpas & Loizos (eds)

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    7. Low temperature cracking in HMA 367 #12;#12;Pavement Cracking ­ Al-Qadi, Scarpas & Loizos (eds, Storrs, Connecticut, USA ABSTRACT: Low temperature cracking remains one of the major pavement distresses in asphalt concrete pavements in cold regions. An integrated laboratory testing, field performance data

  20. Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Publications Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons...

  1. Measurement of diesel solid nanoparticle emissions using a catalytic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    diesel solid nanoparticle emissions using a catalytic stripper for comparison with Europe's PMP protocol Measurement of diesel solid nanoparticle emissions using a catalytic...

  2. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys....

  3. High Catalytic Rates for Hydrogen Production Using Nickel Electrocatal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    High Catalytic Rates for Hydrogen Production Using Nickel Electrocatalysts with Seven-Membered Diphosphine Ligands Containing High Catalytic Rates for Hydrogen Production Using...

  4. Nanoporous carbon catalytic membranes and method for making the same

    DOE Patents [OSTI]

    Foley, Henry C. (Hockessin, DE); Strano, Michael (Wilmington, DE); Acharya, Madhav (New Castle, DE); Raich, Brenda A. (Houston, TX)

    2002-01-01T23:59:59.000Z

    Catalytic membranes comprising highly-dispersed, catalytically-active metals in nanoporous carbon membranes and a novel single-phase process to produce the membranes.

  5. Understanding crack versus cavitation in pressure-sensitive adhesives: the role of kinetics

    E-Print Network [OSTI]

    Jérémie Teisseire; F. Nallet; P. Fabre; Cyprien Gay

    2006-09-18T23:59:59.000Z

    We perform traction experiments on viscous liquids highly confined between parallel plates, a geometry known as the probe-tack test in the adhesion community. Direct observation during the experiment coupled to force measurement shows the existence of several mechanisms for releasing the stress. Bubble nucleation and instantaneous growth had been observed in a previous work. Upon increasing further the traction velocity or the viscosity, the bubble growth is progressively delayed. At high velocities, cracks at the interface between the plate and the liquid appear before the bubbles have grown to their full size. Bubbles and cracks are thus observed concomitantly. At even higher velocities, cracks develop fully so early that the bubbles are not even visible. We present a theoretical model that describes these regimes, using a Maxwell fluid as a model for the actual fluid, a highly viscous silicon oil. We present the resulting phase diagramme for the different force peak regimes. The predictions are compatible with the data. Our results show that in addition to cavitation, interfacial cracks are encountered in a probe-tack traction test with viscoelastic, \\emph{liquid} materials and not solely with viscoelastic solids like adhesives.

  6. Fluid juggling

    E-Print Network [OSTI]

    Soto, Enrique

    2013-01-01T23:59:59.000Z

    This fluid dynamics video is an entry for the Gallery of Fluid Motion for the 66th Annual Meeting of the Fluid Dynamics Division of the American Physical Society. We show the curious behaviour of a light ball interacting with a liquid jet. For certain conditions, a ball can be suspended into a slightly inclined liquid jet. We studied this phenomenon using a high speed camera. The visualizations show that the object can be `juggled' for a variety of flow conditions. A simple calculation showed that the ball remains at a stable position due to a Bernoulli-like effect. The phenomenon is very stable and easy to reproduce.

  7. Catalytic converter with thermoelectric generator

    SciTech Connect (OSTI)

    Parise, R.J.

    1998-07-01T23:59:59.000Z

    The unique design of an electrically heated catalyst (EHC) and the inclusion of an ECO valve in the exhaust of an internal combustion engine will meet the strict new emission requirements, especially at vehicle cold start, adopted by several states in this country as well as in Europe and Japan. The catalytic converter (CC) has been a most useful tool in pollution abatement for the automobile. But the emission requirements are becoming more stringent and, along with other improvements, the CC must be improved to meet these new standards. Coupled with the ECO valve, the EHC can meet these new emission limits. In an internal combustion engine vehicle (ICEV), approximately 80% of the energy consumed leaves the vehicle as waste heat: out the tail pipe, through the radiator, or convected/radiated off the engine. Included with the waste heat out the tail pipe are the products of combustion which must meet strict emission requirements. The design of a new CC is presented here. This is an automobile CC that has the capability of producing electrical power and reducing the quantity of emissions at vehicle cold start, the Thermoelectric Catalytic Power Generator. The CC utilizes the energy of the exothermic reactions that take place in the catalysis substrate to produce electrical energy with a thermoelectric generator. On vehicle cold start, the thermoelectric generator is used as a heat pump to heat the catalyst substrate to reduce the time to catalyst light-off. Thus an electrically heated catalyst (EHC) will be used to augment the abatement of tail pipe emissions. Included with the EHC in the exhaust stream of the automobile is the ECO valve. This valve restricts the flow of pollutants out the tail pipe of the vehicle for a specified amount of time until the EHC comes up to operating temperature. Then the ECO valve opens and allows the full exhaust, now treated by the EHC, to leave the vehicle.

  8. Crack shape developments and leak rates for circumferential complex-cracked pipes

    SciTech Connect (OSTI)

    Brickstad, B.; Bergman, M. [SAQ Inspection Ltd., Stockholm (Sweden)

    1997-04-01T23:59:59.000Z

    A computerized procedure has been developed that predicts the growth of an initial circumferential surface crack through a pipe and further on to failure. The crack growth mechanism can either be fatigue or stress corrosion. Consideration is taken to complex crack shapes and for the through-wall cracks, crack opening areas and leak rates are also calculated. The procedure is based on a large number of three-dimensional finite element calculations of cracked pipes. The results from these calculations are stored in a database from which the PC-program, denoted LBBPIPE, reads all necessary information. In this paper, a sensitivity analysis is presented for cracked pipes subjected to both stress corrosion and vibration fatigue.

  9. Fracturing controlled primary migration of hydrocarbon fluids during1 heating of organic-rich shales2

    E-Print Network [OSTI]

    understand primary migration of16 hydrocarbon fluids in very low permeability source rock. Cracks nucleate.e. the transport of hydrocarbon fluids from extremely low39 permeability source rocks in which they are generated the source rock is42 formed is buried, the organic material is transformed into complex high molecular weight

  10. SciTech Connect: CRACK TIP PLASTICITY AND FRACTURE INITIATION...

    Office of Scientific and Technical Information (OSTI)

    N50000* --Metals, Ceramics, & Other Materials; CRACKS; FRACTURE PROPERTIES; METALS BUILDING MATERIALSfracture of metal, crack tip plasticity and initiation criteria for;...

  11. Life prediction for bridged fatigue cracks

    SciTech Connect (OSTI)

    Cox, B.N.

    1994-08-01T23:59:59.000Z

    One of the more promising classes of composites touted for high temperature applications, and certainly the most available, is that of relatively brittle matrices, either ceramic or intermetallic, reinforced by strong, aligned, continuous fibers. Under cyclic loading in the fiber direction, these materials develop matrix cracks that often run perpendicular to the fibers, while the fibers remain intact in the crack wake, supplying bridging tractions across the fracture surfaces. The bridging tractions shield the crack tip from the applied load, dramatically reducing the crack velocity from that expected in an unreinforced material subjected to the same value, {Delta}K{sub a}, of the cyclic applied stress intensity factor. An important issue in reliability is the prediction of the growth rates of the bridged cracks. The growth rates of matrix fatigue cracks bridged by sliding fibers are now commonly predicted by models based on the micromechanics of frictional interfaces. However, there exist many reasons, both theoretical and experimental, for suspecting that the most popular micromechanical models are probably wrong in detail in the context of fatigue cracks. Furthermore, a review of crack growth data reveals that the validity of the micromechanics-based predictive model has never been tested and may never be tested. In this paper, two alternative approaches are suggested to the engineering problem of predicting the growth rates of bridged cracks without explicit recourse to micromechanics. Instead, it is shown that the material properties required to analyze bridging effects can be deduced directly from crack growth data. Some experiments are proposed to test the validity of the proposals.

  12. Seismic waves in rocks with fluids and fractures

    SciTech Connect (OSTI)

    Berryman, J.G.

    2007-05-14T23:59:59.000Z

    Seismic wave propagation through the earth is often stronglyaffected by the presence of fractures. When these fractures are filledwith fluids (oil, gas, water, CO2, etc.), the type and state of the fluid(liquid or gas) can make a large difference in the response of theseismic waves. This paper summarizes recent work on methods ofdeconstructing the effects of fractures, and any fluids within thesefractures, on seismic wave propagation as observed in reflection seismicdata. One method explored here is Thomsen's weak anisotropy approximationfor wave moveout (since fractures often induce elastic anisotropy due tononuniform crack-orientation statistics). Another method makes use ofsome very convenient fracture parameters introduced previously thatpermit a relatively simple deconstruction of the elastic and wavepropagation behavior in terms of a small number of fracture parameters(whenever this is appropriate, as is certainly the case for small crackdensities). Then, the quantitative effects of fluids on thesecrack-influence parameters are shown to be directly related to Skempton scoefficient B of undrained poroelasticity (where B typically ranges from0 to 1). In particular, the rigorous result obtained for the low crackdensity limit is that the crack-influence parameters are multiplied by afactor (1 ? B) for undrained systems. It is also shown how fractureanisotropy affects Rayleigh wave speed, and how measured Rayleigh wavespeeds can be used to infer shear wave speed of the fractured medium.Higher crack density results are also presented by incorporating recentsimulation data on such cracked systems.

  13. 6. Fluid mechanics: fluid statics; fluid dynamics

    E-Print Network [OSTI]

    Zevenhoven, Ron

    Figure Pressure (a scalar!) is defined as surface force / area, for example pb = Fb / (d·w) = p @ z = z1 Picture: KJ05 Fluid volume h·d·w with density and mass m = h·d·w· z = z1 In engineering forces Fn+ Fs = 0 or - py·h·w + py·h·w = 0 py = 0 Similarly Fw+ Fe= 0 gives px = 0, There are three

  14. Early stages in the development of stress corrosion cracks

    SciTech Connect (OSTI)

    Jones, R.H.; Simonen, E.P.

    1993-12-01T23:59:59.000Z

    Processes in growth of short cracks and stage I of long stress corrosion cracks were identified and evaluated. There is evidence that electrochemical effects can cause short stress corrosion cracks to grow at rates faster or slower than long cracks. Short cracks can grow at faster rates than long cracks for a salt film dissolution growth mechanism or from reduced oxygen inhibition of hydrolytic acidification. An increasing crack growth rate with increasing crack length could result from a process of increasing crack tip concentration of a critical anion, such as Cl{sup {minus}}, with increasing crack length in a system where the crack velocity is dependent on the Cl{sup {minus}} or some other anion concentration. An increasing potential drop between crack tip and mouth would result in an increased anion concentration at the crack tip and hence an increasing crack velocity. Stage I behavior of long cracks is another early development stage in the life of a stress corrosion crack which is poorly understood. This stage can be described by da/dt = AK{sup m} where da/dt is crack velocity, A is a constant, K is stress intensity and m ranges from 2 to 24 for a variety of materials and environments. Only the salt film dissolution model was found to quantitatively describe this stage; however, the model was only tested on one material and its general applicability is unknown.

  15. Catalytic gasification of bagasse for the production of methanol

    SciTech Connect (OSTI)

    Baker, E.G.; Brown, M.D.; Robertus, R.J.

    1985-10-01T23:59:59.000Z

    The purpose of the study was to evaluate the technical and economic feasibility of catalytic gasification of bagasse to produce methanol. In previous studies, a catalytic steam gasification process was developed which converted wood to methanol synthesis gas in one step using nickel based catalysts in a fluid-bed gasifier. Tests in a nominal 1 ton/day process development unit (PDU) gasifier with these same catalysts showed bagasse to be a good feedstock for fluid-bed gasifiers, but the catalysts deactivated quite rapidly in the presence of bagasse. Laboratory catalyst screening tests showed K/sub 2/CO/sub 3/ doped on the bagasse to be a promising catalyst for converting bagasse to methanol synthesis gas. PDU tests with 10 wt % K/sub 2/CO/sub 3/ doped on bagasse showed the technical feasibility of this type of catalyst on a larger scale. A high quality synthesis gas was produced and carbon conversion to gas was high. The gasifier was successfully operated without forming agglomerates of catalyst, ash, and char in the gasifier. There was no loss of activity throughout the runs because catalysts is continually added with the bagasse. Laboratory tests showed about 80% of the potassium carbonate could be recovered and recycled with a simple water wash. An economic evaluation of the process for converting bagasse to methanol showed the required selling price of methanol to be significantly higher than the current market price of methanol. Several factors make this current evaluaton using bagasse as a feedstock less favorable: (1) capital costs are higher due to inflation and some extra costs required to use bagasse, (2) smaller plant sizes were considered so economies of scale are lost, and (3) the market price of methanol in the US has fallen 44% in the last six months. 24 refs., 14 figs., 16 tabs.

  16. Studies on fruit cracking of tomatoes

    E-Print Network [OSTI]

    Cotner, Sam Don

    1966-01-01T23:59:59.000Z

    calcium , 33 Means for naturally occurring cracks as influenced by foliar calcium applications 33 Analysis of variance for tomato fruit cracking as influended by foliar applications of CaC12 36 LIST QF TABLES CONTINUED 17. Analysis of variance...on of the cell contents oi' tomato fruits late in the season have been reported (10). Whatley (37) states that there is a 20 percent increase in osmot1c pressure from mature green to the red ripe stags. Radial cracking may be due to an increase...

  17. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO)

    2001-01-01T23:59:59.000Z

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  18. CRACK SPACING IN STRAINED FILMS B.B. Guzina1

    E-Print Network [OSTI]

    Guzina, Bojan

    , similar transverse cracking patterns are a feature of asphalt concrete pavements systems in cold climates

  19. Coding the cracks | Argonne Leadership Computing Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    . October 3, 2014 Printer-friendly version Researchers use Mira to study stress-corrosion cracking in silicates Encased in the rocks that comprise much of Earth's crust and...

  20. Cracking in reinforced concrete bent caps 

    E-Print Network [OSTI]

    Young, Bradley S.

    2000-01-01T23:59:59.000Z

    by studying the relationship between stresses in the longitudinal tension reinforcement, reinforcement detailing, shear resistance, and cracking of the bent cap during service loading through to failure. As a part of this investigation, sixteen full...

  1. Shrinkage - cracking characteristics of structural lightweight concrete

    E-Print Network [OSTI]

    McKeen, Robert Gordon

    1969-01-01T23:59:59.000Z

    1969 ABSTRACT Shrinkage-Cracking Characteristics of Structural Lightweight Concrete (August 1969) B. S. C. E. , Texas AERY University Directed by: if. B. Ledbetter Tests were conducted to det. trains the effect of coarse. s -gre- gate type...'csults indicated that both unrestrained shrinkage and concret. c water loss relate to restrained shrinkage stress. Unrestrained shrinks e did not indicate. cracking ter. dency while we+ er loss provided an indi cati on of cr cking tendency. ACRRO!Jr. ROOD. i...

  2. Simulating Fluids Exhibiting Microstructure

    E-Print Network [OSTI]

    Title: Simulating Fluids Exhibiting Microstructure Speaker: Noel J. Walkington, ... fluids containing elastic particles, and polymer fluids, all exhibit non-trivial ...

  3. Selective oxidation of hydrocarbons in a catalytic dense membrane reactor: Catalytic properties of BIMEVOX (Me = Ta)

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Selective oxidation of hydrocarbons in a catalytic dense membrane reactor: Catalytic properties for syngas or H2 production from light hydrocarbons. #12;2 Keywords: Dense membrane reactor, BIMEVOX, BITAVOX to decouple the two steps of the redox mechanism that prevails in selective oxidation of hydrocarbons [1

  4. VOC Destruction by Catalytic Combustion Microturbine

    SciTech Connect (OSTI)

    Tom Barton

    2009-03-10T23:59:59.000Z

    This project concerned the application of a catalytic combustion system that has been married to a micro-turbine device. The catalytic combustion system decomposes the VOC's and transmits these gases to the gas turbine. The turbine has been altered to operate on very low-level BTU fuels equivalent to 1.5% methane in air. The performance of the micro-turbine for VOC elimination has some flexibility with respect to operating conditions, and the system is adaptable to multiple industrial applications. The VOC source that was been chosen for examination was the emissions from coal upgrading operations. The overall goal of the project was to examine the effectiveness of a catalytic combustion based system for elimination of VOCs while simultaneously producing electrical power for local consumption. Project specific objectives included assessment of the feasibility for using a Flex-Microturbine that generates power from natural gas while it consumes VOCs generated from site operations; development of an engineering plan for installation of the Flex-Microturbine system; operation of the micro-turbine through various changes in site and operation conditions; measurement of the VOC destruction quantitatively; and determination of the required improvements for further studies. The micro-turbine with the catalytic bed worked effectively to produce power on levels of fuel much lower than the original turbine design. The ability of the device to add or subtract supplemental fuel to augment the amount of VOC's in the inlet air flow made the device an effective replacement for a traditional flare. Concerns about particulates in the inlet flow and the presence of high sulfur concentrations with the VOC mixtures was identified as a drawback with the current catalytic design. A new microturbine design was developed based on this research that incorporates a thermal oxidizer in place of the catalytic bed for applications where particulates or contamination would limit the lifetime of the catalytic bed.

  5. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect (OSTI)

    W. R. Laster; E. Anoshkina; P. Szedlacsek

    2006-03-31T23:59:59.000Z

    Under the sponsorship of the U.S. Department of Energy's National Energy Technology Laboratory, Siemens Westinghouse is conducting a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1-Implementation Plan, Phase 2-Validation Testing and Phase 3-Field Testing. The Phase 1 program has been completed. Phase II was initiated in October 2004. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCL{trademark}) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to react part of the fuel, increasing the fuel/air mixture temperature. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the catalytic concept will be demonstrated through subscale testing. Phase III will consist of full-scale combustor basket testing on natural gas and syngas.

  6. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect (OSTI)

    W. R. Laster; E. Anoshkina

    2008-01-31T23:59:59.000Z

    Under the sponsorship of the U. S. Department of Energy's National Energy Technology Laboratory, Siemens Westinghouse has conducted a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1 - Implementation Plan, Phase 2 - Validation Testing and Phase 3 - Field Testing. Both Phase 1 and Phase 2 of the program have been completed. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCLTM) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to oxidize a portion of the fuel, increasing the temperature of fuel/air mixture prior to the main combustion zone. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the technology necessary for the application of the catalytic concept to IGCC fuels was developed through detailed design and subscale testing. Phase III (currently not funded) will consist of full-scale combustor basket testing on natural gas and syngas.

  7. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect (OSTI)

    Laster, W. R.; Anoshkina, E.

    2008-01-31T23:59:59.000Z

    Under the sponsorship of the U. S. Department of Energy’s National Energy Technology Laboratory, Siemens Westinghouse has conducted a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1- Implementation Plan, Phase 2- Validation Testing and Phase 3 – Field Testing. Both Phase 1 and Phase 2 of the program have been completed. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCLTM) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to oxidize a portion of the fuel, increasing the temperature of fuel/air mixture prior to the main combustion zone. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the technology necessary for the application of the catalytic concept to IGCC fuels was developed through detailed design and subscale testing. Phase III (currently not funded) will consist of full-scale combustor basket testing on natural gas and syngas.

  8. Modeling and Optimization of Direct Chill Casting to Reduce Ingot Cracking

    SciTech Connect (OSTI)

    Das, Subodh K.

    2006-01-09T23:59:59.000Z

    A successful four-year project on the modeling and optimization of direct chill (DC) casting to reduce ingot cracking has been completed. The project involved close collaboration among private industries, national laboratories, and universities. During the four-year project, 16 quarterly meetings brought the industrial partners and the research team together for discussion of research results and research direction. The industrial partners provided guidance, facilities, and experience to the research team. The research team went to two industrial plants to measure temperature distributions in commercial 60,000-lb DC casting ingot. The collaborative research resulted in several major accomplishments or findings: (1) Surface cracks were shown to be a result of hot tearing rather than cold cracks, as was thought before this project. These cracks form on the surface of a DC cast ingot just above the impingement point of the secondary cooling water jets. The cracks form along dendrite and grain boundaries, where solute and impurity elements are highly segregated. This understanding led to the development of a new technique for determining the mechanical properties in the nonequilibrium mushy zone of alloys and to thermodynamic predictions of the hot tearing propensity of DC cast ingots. (2) The apparent heat transfer coefficient (HTC) at the ingot surface in the water cooling region during DC casting was determined on the basis of temperature measurements in commercial DC casting ingots and an inverse heat transfer analysis. HTCs were calculated as a function of temperature and time, and covered the different regimes of heat transfer expected during DC casting. The calculated values were extrapolated to include the effect of water flow rate. The calculated HTCs had a peak at around 200 C, corresponding to the high heat transfer rates during nucleate boiling, and the profile was consistent with similar data published in the literature. (3) A new method, termed the reheating-cooling method (RCM), was developed and validated for measuring mechanical properties in the nonequilibrium mushy zones of alloys. The new method captures the brittle nature of aluminum alloys at temperatures close to the nonequilibrium solidus temperature, while specimens tested using the reheating method exhibit significant ductility. The RCM has been used for determining the mechanical properties of alloys at nonequilibrium mushy zone temperatures. Accurate data obtained during this project show that the metal becomes more brittle at high temperatures and high strain rates. (4) The elevated-temperature mechanical properties of the alloy were determined. Constitutive models relating the stress and strain relationship at elevated temperatures were also developed. The experimental data fit the model well. (5) An integrated 3D DC casting model has been used to simulate heat transfer, fluid flow, solidification, and thermally induced stress-strain during casting. A temperature-dependent HTC between the cooling water and the ingot surface, cooling water flow rate, and air gap were coupled in this model. An elasto-viscoplastic model based on high-temperature mechanical testing was used to calculate the stress during casting. The 3D integrated model can be used for the prediction of temperature, fluid flow, stress, and strain distribution in DC cast ingots. (6) The cracking propensity of DC cast ingots can be predicted using the 3D integrated model as well as thermodynamic models. Thus, an ingot cracking index based on the ratio of local stress to local alloy strength was established. Simulation results indicate that cracking propensity increases with increasing casting speed. The composition of the ingots also has a major effect on cracking formation. It was found that copper and zinc increase the cracking propensity of DC cast ingots. The goal of this Aluminum Industry of the Future (IOF) project was to assist the aluminum industry in reducing the incidence of stress cracks in DC castings from a current level of 5% down to 2%. This could lead to energy savings

  9. Topology of desiccation crack patterns in clay and invariance of crack interface area with thickness

    E-Print Network [OSTI]

    Tajkera Khatun; Tapati Dutta; Sujata Tarafdar

    2014-12-09T23:59:59.000Z

    We study the crack patterns developed on desiccating films of an aqueous colloidal suspension of bentonite on a glass substrate. Varying the thickness of the layer $h$ gives the following new and interesting results: (i)We identify a critical thickness $h_{c}$, above which isolated cracks join each other to form a fully connected network. A topological analysis of the crack network shows that the Euler number falls to a minimum at $h_{c}$. (ii) We find further, that the total vertical surface area of the clay $A_v$, which has opened up due to cracking, is a constant independent of the layer thickness for $h \\geq h_c$. (iii) The total area of the glass substrate $A_s$, exposed by the hierarchical sequence of cracks is also a constant for $h \\geq h_c$. These results are shown to be consistent with a simple energy conservation argument, neglecting dissipative losses. (iv) Finally we show that if the crack pattern is viewed at successively finer resolution, the total cumulative area of cracks visible at a certain resolution, scales with the layer thickness. A suspension of Laponite in methanol is found to exhibit similar salient features (i)-(iv), though in this case the crack initiation process for very thin layers is quite different.

  10. Contstraint effects of shallow cracks in structures containing fillet weld toe cracks

    E-Print Network [OSTI]

    Neligon, Melinda T

    1995-01-01T23:59:59.000Z

    for structures containing a/W--O.l and a/W--O.5 fillet weld toe cracks. The Anderson-Dodds scaling model is applied to quantify the effects of finite size on J contour integral values for structures containing a/W=O.l and a/W=0.5 fillet weld toe cracks loaded...

  11. Contstraint effects of shallow cracks in structures containing fillet weld toe cracks 

    E-Print Network [OSTI]

    Neligon, Melinda T

    1995-01-01T23:59:59.000Z

    for structures containing a/W--O.l and a/W--O.5 fillet weld toe cracks. The Anderson-Dodds scaling model is applied to quantify the effects of finite size on J contour integral values for structures containing a/W=O.l and a/W=0.5 fillet weld toe cracks loaded...

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

    SciTech Connect (OSTI)

    Rahman, S.; Brust, F.; Ghadiali, N.; Wilkowski, G.; Miura, N.

    1997-04-01T23:59:59.000Z

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

  13. TRANSPORT THROUGH CRACKED CONCRETE: LITERATURE REVIEW

    SciTech Connect (OSTI)

    Langton, C.

    2012-05-11T23:59:59.000Z

    Concrete containment structures and cement-based fills and waste forms are used at the Savannah River Site to enhance the performance of shallow land disposal systems designed for containment of low-level radioactive waste. Understanding and measuring transport through cracked concrete is important for describing the initial condition of radioactive waste containment structures at the Savannah River Site (SRS) and for predicting performance of these structures over time. This report transmits the results of a literature review on transport through cracked concrete which was performed by Professor Jason Weiss, Purdue University per SRR0000678 (RFP-RQ00001029-WY). This review complements the NRC-sponsored literature review and assessment of factors relevant to performance of grouted systems for radioactive waste disposal. This review was performed by The Center for Nuclear Waste Regulatory Analyses, San Antonio, TX, and The University of Aberdeen, Aberdeen Scotland and was focused on tank closure. The objective of the literature review on transport through cracked concrete was to identify information in the open literature which can be applied to SRS transport models for cementitious containment structures, fills, and waste forms. In addition, the literature review was intended to: (1) Provide a framework for describing and classifying cracks in containment structures and cementitious materials used in radioactive waste disposal, (2) Document the state of knowledge and research related to transport through cracks in concrete for various exposure conditions, (3) Provide information or methodology for answering several specific questions related to cracking and transport in concrete, and (4) Provide information that can be used to design experiments on transport through cracked samples and actual structures.

  14. Fluid extraction

    DOE Patents [OSTI]

    Wai, Chien M. (Moscow, ID); Laintz, Kenneth E. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

  15. STRESS CORROSION CRACKING IN TEAR DROP SPECIMENS

    SciTech Connect (OSTI)

    Lam, P; Philip Zapp, P; Jonathan Duffey, J; Kerry Dunn, K

    2009-05-01T23:59:59.000Z

    Laboratory tests were conducted to investigate the stress corrosion cracking (SCC) of 304L stainless steel used to construct the containment vessels for the storage of plutonium-bearing materials. The tear drop corrosion specimens each with an autogenous weld in the center were placed in contact with moist plutonium oxide and chloride salt mixtures. Cracking was found in two of the specimens in the heat affected zone (HAZ) at the apex area. Finite element analysis was performed to simulate the specimen fabrication for determining the internal stress which caused SCC to occur. It was found that the tensile stress at the crack initiation site was about 30% lower than the highest stress which had been shifted to the shoulders of the specimen due to the specimen fabrication process. This finding appears to indicate that the SCC initiation took place in favor of the possibly weaker weld/base metal interface at a sufficiently high level of background stress. The base material, even subject to a higher tensile stress, was not cracked. The relieving of tensile stress due to SCC initiation and growth in the HAZ and the weld might have foreclosed the potential for cracking at the specimen shoulders where higher stress was found.

  16. Crack detection using pulsed eddy current stimulated thermography

    SciTech Connect (OSTI)

    Kostson, E.; Weekes, B.; Almond, D. P. [RCNDE, Department of Mechanical Engineering, University of Bath (United Kingdom); Wilson, J.; Tian, G. Y. [School of Electrical, Electronic and Computer Engineering, Newcastle University (United Kingdom)

    2011-06-23T23:59:59.000Z

    This contribution presents results from studies investigating factors that influence the detection of surface breaking cracks using pulsed eddy current thermography. The influences of the current strength and crack orientation in both ferromagnetic and non-ferromagnetic metals have been investigated. It has been found that crack detection is far more sensitive to crack orientation in non-ferromagnetic metals than in ferromagnetic metals. The effects of crack size on detectability are presented for a large number of steel, nickel alloy and titanium samples. Results of studies comparing crack images obtained prior and after coating a nickel alloy sample with a thermal barrier coating are presented.

  17. Electro Catalytic Oxidation (ECO) Operation

    SciTech Connect (OSTI)

    Morgan Jones

    2011-03-31T23:59:59.000Z

    The power industry in the United States is faced with meeting many new regulations to reduce a number of air pollutants including sulfur dioxide, nitrogen oxides, fine particulate matter, and mercury. With over 1,000 power plants in the US, this is a daunting task. In some cases, traditional pollution control technologies such as wet scrubbers and SCRs are not feasible. Powerspan's Electro-Catalytic Oxidation, or ECO{reg_sign} process combines four pollution control devices into a single integrated system that can be installed after a power plant's particulate control device. Besides achieving major reductions in emissions of sulfur dioxide (SO{sub 2}), nitrogen oxides (NOx), fine particulate matter (PM2.5) and mercury (Hg), ECO produces a highly marketable fertilizer, which can help offset the operating costs of the process system. Powerspan has been operating a 50-MW ECO commercial demonstration unit (CDU) at FirstEnergy Corp.'s R.E. Burger Plant near Shadyside, Ohio, since February 2004. In addition to the CDU, a test loop has been constructed beside the CDU to demonstrate higher NOx removal rates and test various scrubber packing types and wet ESP configurations. Furthermore, Powerspan has developed the ECO{reg_sign}{sub 2} technology, a regenerative process that uses a proprietary solvent to capture CO{sub 2} from flue gas. The CO{sub 2} capture takes place after the capture of NOx, SO{sub 2}, mercury, and fine particulate matter. Once the CO{sub 2} is captured, the proprietary solution is regenerated to release CO{sub 2} in a form that is ready for geological storage or beneficial use. Pilot scale testing of ECO{sub 2} began in early 2009 at FirstEnergy's Burger Plant. The ECO{sub 2} pilot unit is designed to process a 1-MW flue gas stream and produce 20 tons of CO{sub 2} per day, achieving a 90% CO{sub 2} capture rate. The ECO{sub 2} pilot program provided the opportunity to confirm process design and cost estimates, and prepare for large scale capture and sequestration projects. The objectives of this project were to prove at a commercial scale that ECO is capable of extended operations over a range of conditions, that it meets the reliability requirements of a typical utility, and that the fertilizer co-product can be consistently generated, providing ECO with an economic advantage over conventional technologies currently available. Further objectives of the project were to show that the ECO system provides flue gas that meets the inlet standards necessary for ECO{sub 2} to operate, and that the outlet CO{sub 2} and other constituents produced by the ECO{sub 2} pilot can meet Kinder-Morgan pipeline standards for purposes of sequestration. All project objectives are consistent with DOE's Pollution Control Innovations for Power Plants program goals.

  18. Porous Core-Shell Nanostructures for Catalytic Applications

    E-Print Network [OSTI]

    Ewers, Trevor David

    2012-01-01T23:59:59.000Z

    C.Y Mou. Catalytic nano-rattle of Au@ hollow silica: towardshollow nanostructures induced by the Kirkendall effect: The basic concept. NanoHollow mesoporous aluminosilica spheres with perpendicular pore channels as catalytic nanoreactors. ACS Nano,

  19. Environmentally assisted cracking of LWR materials.

    SciTech Connect (OSTI)

    Chopra, O. K.; Chung, H. M.; Kassner, T. F.; Park, J. H.; Shack, W. J.; Zhang, J.; Brust, F. W.; Dong, P.

    1997-12-05T23:59:59.000Z

    The effect of dissolved oxygen level on fatigue life of austenitic stainless steels is discussed and the results of a detailed study of the effect of the environment on the growth of cracks during fatigue initiation are presented. Initial test results are given for specimens irradiated in the Halden reactor. Impurities introduced by shielded metal arc welding that may affect susceptibility to stress corrosion cracking are described. Results of calculations of residual stresses in core shroud weldments are summarized. Crack growth rates of high-nickel alloys under cyclic loading with R ratios from 0.2-0.95 in water that contains a wide range of dissolved oxygen and hydrogen concentrations at 289 and 320 C are summarized.

  20. Crack detection using resonant ultrasound spectroscopy

    DOE Patents [OSTI]

    Migliori, Albert (Santa Fe, NM); Bell, Thomas M. (Santa Fe, NM); Rhodes, George W. (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    Method and apparatus are provided for detecting crack-like flaws in components. A plurality of exciting frequencies are generated and applied to a component in a dry condition to obtain a first ultrasonic spectrum of the component. The component is then wet with a selected liquid to penetrate any crack-like flaws in the component. The plurality of exciting frequencies are again applied to the component and a second ultrasonic spectrum of the component is obtained. The wet and dry ultrasonic spectra are then analyzed to determine the second harmonic components in each of the ultrasonic resonance spectra and the second harmonic components are compared to ascertain the presence of crack-like flaws in the component.

  1. Crack detection using resonant ultrasound spectroscopy

    DOE Patents [OSTI]

    Migliori, A.; Bell, T.M.; Rhodes, G.W.

    1994-10-04T23:59:59.000Z

    Method and apparatus are provided for detecting crack-like flaws in components. A plurality of exciting frequencies are generated and applied to a component in a dry condition to obtain a first ultrasonic spectrum of the component. The component is then wet with a selected liquid to penetrate any crack-like flaws in the component. The plurality of exciting frequencies are again applied to the component and a second ultrasonic spectrum of the component is obtained. The wet and dry ultrasonic spectra are then analyzed to determine the second harmonic components in each of the ultrasonic resonance spectra and the second harmonic components are compared to ascertain the presence of crack-like flaws in the component. 5 figs.

  2. Demetallization of asphaltenes: Thermal and catalytic effects with small-pore catalysts

    SciTech Connect (OSTI)

    Adarme, R. (Oklahoma State Univ., Stillwater, OK (United States)); Sughrue, E.L.; Johnson, M.M.; Kidd, D.R.; Phillips, M.D.; Shaw, J.E. (Phillips Petroleum Co., Bartlesville, OK (United States))

    1990-08-01T23:59:59.000Z

    Residual oil hydrotreating has become an important front end process in commercial oil upgrading schemes because of tighter environmental regulations and a continuing trend toward processing heavier crudes. At Phillips Petroleum, residual oil hydrotreating pretreates feed for heavy oil cracking (HOC) by removing sulfur, a pollutant in the HOC stack gas, and metals such as nickel and vanadium, which adversely affect the cracking catalyst and gasoline yield in the HOC. Metals in residual oil are found almost exclusively in the resin and asphaltene fractions. Research has showed that metals in the resin fraction react more rapidly than metals in the asphaltene fraction. The hydrodemetallization (HDM) reaction is known to be diffusion limited and the larger molecular size of the asphaltene molecules may explain the slower reaction rates. Richardson and Alley and Asaoka, et al. have shown a reduction in asphaltene molecular weights with thermal and catalytic processing. Reynolds and Biggs demonstrated shifts in vanadium size distributions from thermally and catalytically treated residual. Recently Savage and Javanmaridian showed theoretically that reduction in molecular sizes external to catalyst pellets increases the reaction rate by as much as the inverse of the effectiveness factor. This work attempts to extend information on how metals are removed from asphaltenes and the interaction with small-pore catalysts generally found at the back end of residual oil hydrotreaters, where they are protected from deactivation by metal deposition. The small-pore catalysts are generally high in hydrodesulfurization (HDS) activity and generally restrict the large asphaltene molecules from entering their pores and depositing metals.

  3. Fast electromigration crack in nanoscale aluminum film

    SciTech Connect (OSTI)

    Emelyanov, O. A., E-mail: oaemel2@gmail.com; Ivanov, I. O. [St. Petersburg State Polytechnical University, Saint-Petersburg (Russian Federation)

    2014-08-14T23:59:59.000Z

    The current-induced breakage of 20?nm thin aluminum layers deposited onto capacitor grade polypropylene (PP) films is experimentally studied. Biexponential current pulses of different amplitude (10–15?A) and duration (0.1–1??s) were applied to the samples. Breakage occurred after fast development of electromigrating ?200?nm-wide cracks with initial propagation velocity of ?1?m/s under a high current density of ?10{sup 12?}A/m{sup 2}. The cracks stopped when their lengths reached 250–450??m. This behavior is explained by the balance of electromigration and stress-induced atomic fluxes.

  4. CATALYTICALLY ENCHANCED SYSTEMS FOR HYDROGEN STORAGE

    E-Print Network [OSTI]

    to the conversion of the world to a "hydrogen economy" is the problem of onboard hydrogen storage. Despite decadesCATALYTICALLY ENCHANCED SYSTEMS FOR HYDROGEN STORAGE Craig M. Jensen, Dalin Sun, Sesha Sai RamanH/Al and the reverse hydrogenation reactions have been determined through kinetic studies of 2 mol % Ti and Zr doped

  5. Transparent and Catalytic Carbon Nanotube Films

    E-Print Network [OSTI]

    Hone, James

    for the dye-sensitized solar cell. Other possible applications include batteries, fuel cells and intercalation in hydrogen fuel cells and lithium ion batteries.1,10,12,14 However, the electrochemical activity to optimize performance through processing. In this study, we quantify the catalytic activity of single

  6. Crack closure effects on fatigue crack growth thresholds and remaining life in an HSLA steel

    SciTech Connect (OSTI)

    Todd, J.A.; Mostovoy, S. [Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Mechanical, Materials and Aerospace Engineering; Chen, L. [Texas Instruments, Attleboro, MA (United States); Yankov, E.Y. [A. Finkl and Sons, Chicago, IL (United States)

    1997-02-01T23:59:59.000Z

    The effects of crack closure on the near-threshold corrosion fatigue crack growth behavior of Mil S-24645 HSLA steel and its weld metal have been investigated in air, ASTM seawater at the free corrosion potential, and ASTM seawater at {minus}0.8V and {minus}1.0V (SCE) using frequencies of 10, 2, and 0.2 Hz, and a stress ratio, R = 0.1. Remaining life, in the presence and absence of crack closure, has been estimated as a function of applied stress range for a structure containing a 3-mm-deep surface semi-elliptical flaw.

  7. Reflective Cracking Study: HVS Test Section Forensic Investigation

    E-Print Network [OSTI]

    Jones, David; Steven, B.; Harvey, John T

    2008-01-01T23:59:59.000Z

    the asphalt concrete. Summary of Testing on the Underlyingtesting performed to validate Caltrans overlay strategies for the rehabilitation of cracked asphalt concrete.concrete. It describes the forensic investigation of the HVS rutting and reflective cracking testing

  8. Characterization of Fatigue Cracking and Healing of Asphalt Mixtures

    E-Print Network [OSTI]

    Luo, Xue

    2012-07-16T23:59:59.000Z

    mixtures using an energy-based mechanistic approach. A controlled-strain repeated direct tension (RDT) test is selected to generate both fatigue cracking and permanent deformation in an asphalt mixture specimen. Fatigue cracking is separated from...

  9. Grain Boundary Structure Effects on Intergranular Stress Corrosion Cracking of

    E-Print Network [OSTI]

    Olson, Tamara

    Grain Boundary Structure Effects on Intergranular Stress Corrosion Cracking of Alloy X­750 Y. Pan B­of­freedom) and correlations with intergranular stress corrosion cracking observed in Alloy X­750. Orientation imaging

  10. A dynamical law for slow crack growth in polycarbonate films

    E-Print Network [OSTI]

    Cortet, Pierre-Philippe; Ciliberto, Sergio

    2007-01-01T23:59:59.000Z

    We study experimentally the slow growth of a single crack in polycarbonate films submitted to uniaxial and constant imposed stress. For this visco-plastic material, we uncover a dynamical law that describes the dependence of the instantaneous crack velocity with experimental parameters. The law involves a Dugdale-Barenblatt static description of crack tip plastic zones associated to an Eyring's law and an empirical dependence with the crack length that may come from a residual elastic field.

  11. Prediction of thermal crack spacing D.H. Timm a

    E-Print Network [OSTI]

    Guzina, Bojan

    understanding of thin film coatings but an understanding of how so-called thermal cracks, a feature of cold

  12. autogenous shrinkage cracking: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Restrained Shrinkage Cracking of Concrete Materials," 15th International Glass Fibre Reinforced Concrete Association Engineering Websites Summary: . The experiments...

  13. Catalytic co-processing of coal with bitumen and bitumen derived liquids

    SciTech Connect (OSTI)

    Chakma, A.; Zaman, J. [Univ. of Calgary, Alberta (Canada)

    1993-12-31T23:59:59.000Z

    Experimental studies on the co-processing of coal with bitumen and bitumen derived liquids are described. A subbituminous coal was coprocessed with Athabasca bitumen and its various liquid fractions in a batch autoclave under hydrogen pressure at reaction temperatures varying from 400 to 440{degrees}C. Both thermal and catalytic coprocessing experiments were conducted. The catalysts used were molten halide type and included ZnCl{sub 2}, MoCl{sub 5}, KCl, CuCl, and SnCl{sub 2}. Higher reaction temperature resulted in higher conversion of asphaltenes into both maltenes and coke and gases. As a result the H/C atomic ratio of the unconverted asphaltenes decreased with temperature. Higher reaction time on the other hand allowed maltenes to be converted to asphaltenes. While all the catalysts tested had catalytic effects on asphaltene conversion, MoCl{sub 5} was found to provide the highest conversion of asphaltenes due to its ability to hydrogenate the radicals formed due to asphaltene cracking. Processing of coal with bitumen derived liquids provided higher yields than those obtained with virgin bitumen. The H/C ratios were also higher for the products obtained with bitumen derived liquids.

  14. CRACK STATISTIC OF CRYSTALLINE SILICON PHOTOVOLTAIC MODULES M. Kntges1

    E-Print Network [OSTI]

    the risk of cracks, as well as for statistical power loss assessment. Keywords: PV module, micro cracks separation, thus resulting in inactive cell parts. For this special case a clear assessment of the power loss this gap and provide a first statistic of cracks in PV modules for future power loss assessment

  15. RESEARCH Open Access Pavement crack characteristic detection based

    E-Print Network [OSTI]

    Joensuu, University of

    RESEARCH Open Access Pavement crack characteristic detection based on sparse representation Xiaoming Sun1 , Jianping Huang1 , Wanyu Liu1* and Mantao Xu2 Abstract Pavement crack detection plays an important role in pavement maintaining and management. The three- dimensional (3D) pavement crack detection

  16. Immobilization of vanadia deposited on catalytic materials during carbo-metallic oil conversion

    SciTech Connect (OSTI)

    Beck, H.W.; Carruthers, J.D.; Cornelius, E.B.; Hettinger, Jr., W.P.; Kovach, S.M.; Palmer, J.L.; Zandona, O.J.

    1988-06-14T23:59:59.000Z

    This patent describes a process for the cracking of a hydrocarbon oil feed having a significant content of at least 0.1 ppm vanadium to lighter oil products. The process consists of contacting the feed under conversion conditions in a conversion zone with a catalyst containing a precipitated metal additive to immobilize vanadium compounds by forming compounds therewith that have melting points above temperatures found in regenerating a coked catalyst; and having catalytic cracking characteristics, coke and vanadium being deposited on the catalyst by the contact; regenerating the coked catalyst in the presence of an oxygen containing gas at a temperature sufficient to remove at least some of the coke, and, recycling the regenerated catalyst to the conversion zone for contact with fresh feed; the metal additive being present on the catalyst in an amount sufficient to immobilize at least a portion of the vanadium compound in the presence of the oxygen containing gas at the catalyst regeneration temperature; wherein the metal additive to immobilize vanadium compounds deposited on the catalyst is selected from the group consisting of Sr, Sc, Y, Nb, and Ta elements, and an element in the actinide series, or a combination of two or more of the elements.

  17. Enhanced ultrasonic detection of fatigue cracks by laser-induced crack closure

    E-Print Network [OSTI]

    Nagy, Peter B.

    , corrosion, etc. . Sec- ond, it is important to distinguish small fatigue cracks as early as possible after threshold in aluminum, aluminum­ lithium, and titanium alloys.1 For example, extensive multiple-site fatigue

  18. Stress corrosion cracking and crack tip characterization of Alloy X-750 in light water reactor environments

    E-Print Network [OSTI]

    Gibbs, Jonathan Paul

    2011-01-01T23:59:59.000Z

    Stress corrosion cracking (SCC) susceptibility of Inconel Alloy X-750 in the HTH condition has been evaluated in high purity water at 93 and 288°C under Boiling Water Reactor Normal Water Chemistry (NWC) and Hydrogen Water ...

  19. Stress Corrosion Cracking and Crack Tip Characterization of Alloy X-750 in Light Water Reactor Environments

    E-Print Network [OSTI]

    Gibbs, Jonathan Paul

    Stress corrosion cracking (SCC) susceptibility of Inconel Alloy X-750 in the HTH condition has been evaluated in high purity water at 93 and 288°C under Boiling Water Reactor Normal Water Chemistry (NWC) and Hydrogen Water ...

  20. The true toughness of human cortical bone measured with realistically short cracks

    E-Print Network [OSTI]

    Ritchie, Robert

    crack-resistance curves. We find that after only 500 µm of cracking, the driving force for crack. However, the toughness in the longitudinal orientation, where cracks tend to follow the cement lines mechanisms, which act primarily in the crack wake to `shield' the crack from the applied driving force

  1. Digital radiographic systems detect boiler tube cracks

    SciTech Connect (OSTI)

    Walker, S. [EPRI, Charlotte, NC (United States)

    2008-06-15T23:59:59.000Z

    Boiler water wall leaks have been a major cause of steam plant forced outages. But conventional nondestructive evaluation techniques have a poor track record of detecting corrosion fatigue cracking on the inside surface of the cold side of waterwall tubing. EPRI is performing field trials of a prototype direct-digital radiographic system that promises to be a game changer. 8 figs.

  2. Environmentally assisted cracking in light water reactors

    SciTech Connect (OSTI)

    Chopra, O.K.; Chung, H.M.; Gruber, E.E. [and others

    1996-07-01T23:59:59.000Z

    This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) from April 1995 to December 1995. Topics that have been investigated include fatigue of carbon and low-alloy steel used in reactor piping and pressure vessels, EAC of Alloy 600 and 690, and irradiation-assisted stress corrosion cracking (IASCC) of Type 304 SS. Fatigue tests were conducted on ferritic steels in water that contained various concentrations of dissolved oxygen (DO) to determine whether a slow strain rate applied during different portions of a tensile-loading cycle are equally effective in decreasing fatigue life. Crack-growth-rate tests were conducted on compact-tension specimens from several heats of Alloys 600 and 690 in simulated LWR environments. Effects of fluoride-ion contamination on susceptibility to intergranular cracking of high- and commercial- purity Type 304 SS specimens from control-tensile tests at 288 degrees Centigrade. Microchemical changes in the specimens were studied by Auger electron spectroscopy and scanning electron microscopy to determine whether trace impurity elements may contribute to IASCC of these materials.

  3. Application of the cracked pipe element to creep crack growth prediction

    SciTech Connect (OSTI)

    Brochard, J.; Charras, T.

    1997-04-01T23:59:59.000Z

    The modification of a computer code for leak before break analysis is very briefly described. The CASTEM2000 code was developed for ductile fracture assessment of piping systems with postulated circumferential through-wall cracks under static or dynamic loading. The modification extends the capabilities of the cracked pipe element to the determination of fracture parameters under creep conditions (C*, {phi}c and {Delta}c). The model has the advantage of evaluating significant secondary effects, such as those from thermal loading.

  4. Fluid Inclusion Gas Analysis

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Dilley, Lorie

    Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.

  5. Fluid Inclusion Gas Analysis

    SciTech Connect (OSTI)

    Dilley, Lorie

    2013-01-01T23:59:59.000Z

    Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.

  6. Model of crack propagation in a clay soil

    E-Print Network [OSTI]

    Carriere, Patrick Edwidge

    1985-01-01T23:59:59.000Z

    in elevation of the soil surface were recorded over time of drying for each of the treatments. A logarithmic model to predict the crack depth, the crack width, and the drop in elevation of the soil surface expressed by the equation y = A + C*logt, was found... 2 MEANS procedure results for crack depth. 3 ANOVA results for crack depth. 19 29 30 4 Values of A and C obtained from linear regression analysis for crack depth. 35 5 Selection of combinations of independent variables for maximum R...

  7. Why Do Kraft Recovery Boiler Composite Floor Tubes Crack?

    SciTech Connect (OSTI)

    Keiser, J.R.

    2001-10-22T23:59:59.000Z

    Cracks were first reported in 1992 in co-extruded 304L stainless steel/SA210 Gd Al carbon steel floor tubes of North American black liquor recovery boilers. Since then, a considerable amount of information has been collected on the tube environment, crack characteristics, the stress state of the tubes, and the crack initiation and propagation mechanisms. These studies have identified both operating procedures that apparently can greatly lessen the likelihood of crack formation in the stainless steel layer and alternate materials that appear to be much more resistant to cracking than is 304L stainless.

  8. Effect of aging of the pillaring reagent on the microstructure and cracking activity of pillared clay

    SciTech Connect (OSTI)

    Harris, J.R. (Phillips Petroleum Company, Bartlesville, OK (USA))

    1987-08-01T23:59:59.000Z

    Pillared interlayer clay (PILC) is formed by exchanging large hydroxyaluminum polycations into the interlayer of a smectite clay such as montmorillonite, which is made up of sheet-like silica/alumina layers. Calcination of the exchanged clay gives a well dispersed array of metal oxide clumps (i.e., pillars) bonded top and bottom to the silica/alumina layers of the clay. The permanent separation of the clay layers gives an 8 to 10-fold increase in surface area, from 30 to 250-300 m{sup 2}/g, and a microporous structure similar to but less constrained than that of zeolites. Recently, there has been an increased interest in the use of these clays as cracking catalysts. For example, pillared clays have been shown to be an active cracking catalyst for both single component and gas oil feeds. PILC's also lead to both higher light cycle oil (LCO) and coke yields than conventional cracking catalysts. Commercially available, metal-hydrolyzed hydroxyaluminum solutions containing chlorhydrol, A1{sub 2}(OH){sub 5}C1.2H{sub 2}O, have been used as one source of the polycation solution. The approach of these hydrolyzed polycation solutions to equilibrium is known as aging. During the aging process certain polycationic species disappear from the solution and new species are formed. For this reason, the aging process can have a significant influence on the properties of the pillared clays. The objective of this work was to determine how the physical and catalytic properties of the pillared clay depend on the aging of dilute cholorhydrol solutions.

  9. Catalytic fast pyrolysis of lignocellulosic biomass

    SciTech Connect (OSTI)

    Liu, Changjun; Wang, Huamin; Karim, Ayman M.; Sun, Junming; Wang, Yong

    2014-11-21T23:59:59.000Z

    Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy Q3 carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel—bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating values, high corrosiveness, high viscosity, and instability; they also greatly Q4 limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality.

  10. Catalytic extraction processing of contaminated scrap metal

    SciTech Connect (OSTI)

    Griffin, T.P.; Johnston, J.E.; Payea, B.M.; Zeitoon, B.M.

    1995-12-01T23:59:59.000Z

    Molten Metal Technology was awarded a contract to demonstrate the applicability of the Catalytic Extraction Process, a proprietary process that could be applied to US DOE`s inventory of low level mixed waste. This paper is a description of that technology, and included within this document are discussions of: (1) Program objectives, (2) Overall technology review, (3) Organic feed conversion to synthetic gas, (4) Metal, halogen, and transuranic recovery, (5) Demonstrations, (6) Design of the prototype facility, and (7) Results.

  11. Preface: Challenges for Catalytic Exhaust Aftertreatment

    SciTech Connect (OSTI)

    Nova, Isabella; Epling, Bill; Peden, Charles HF

    2014-03-31T23:59:59.000Z

    This special issue of Catalysis Today continues the tradition established since the 18th NAM in Cancun, 2003, of publishing the highlights coming from these catalytic after-treatment technologies sessions, where this volume contains 18 papers based on oral and poster presentations of the 23rd NAM, 2013. The guest editors would like to thank all of the catalyst scientists and engineers who presented in the "Emission control" sessions, and especially the authors who contributed to this special issue of Catalysis Today.

  12. Soil cracking modelling using the mesh-free SPH method

    E-Print Network [OSTI]

    Bui, H H; Kodikara, J; Sanchez, M

    2015-01-01T23:59:59.000Z

    The presence of desiccation cracks in soils can significantly alter their mechanical and hydrological properties. In many circumstances, desiccation cracking in soils can cause significant damage to earthen or soil supported structures. For example, desiccation cracks can act as the preference path way for water flow, which can facilitate seepage flow causing internal erosion inside earth structures. Desiccation cracks can also trigger slope failures and landslides. Therefore, developing a computational procedure to predict desiccation cracking behaviour in soils is vital for dealing with key issues relevant to a range of applications in geotechnical and geo-environment engineering. In this paper, the smoothed particle hydrodynamics (SPH) method will be extended for the first time to simulate shrinkage-induced soil cracking. The main objective of this work is to examine the performance of the proposed numerical approach in simulating the strong discontinuity in material behaviour and to learn about the crack ...

  13. Modeling and Optimization of Direct Chill Casting to Reduce Ingot Cracking

    SciTech Connect (OSTI)

    Das, S.K.; Ningileri, S.; Long, Z.; Saito, K.; Khraisheh, M.; Hassan, M.H.; Kuwana, K.; Han, Q.; Viswanathan, S.; Sabau, A.S.; Clark, J.; Hyrn, J. (ANL)

    2006-08-15T23:59:59.000Z

    Approximately 68% of the aluminum produced in the United States is first cast into ingots prior to further processing into sheet, plate, extrusions, or foil. The direct chill (DC) semi-continuous casting process has been the mainstay of the aluminum industry for the production of ingots due largely to its robust nature and relative simplicity. Though the basic process of DC casting is in principle straightforward, the interaction of process parameters with heat extraction, microstructural evolution, and development of solidification stresses is too complex to analyze by intuition or practical experience. One issue in DC casting is the formation of stress cracks [1-15]. In particular, the move toward larger ingot cross-sections, the use of higher casting speeds, and an ever-increasing array of mold technologies have increased industry efficiencies but have made it more difficult to predict the occurrence of stress crack defects. The Aluminum Industry Technology Roadmap [16] has recognized the challenges inherent in the DC casting process and the control of stress cracks and selected the development of 'fundamental information on solidification of alloys to predict microstructure, surface properties, and stresses and strains' as a high-priority research need, and the 'lack of understanding of mechanisms of cracking as a function of alloy' and 'insufficient understanding of the aluminum solidification process', which is 'difficult to model', as technology barriers in aluminum casting processes. The goal of this Aluminum Industry of the Future (IOF) project was to assist the aluminum industry in reducing the incidence of stress cracks from the current level of 5% to 2%. Decreasing stress crack incidence is important for improving product quality and consistency as well as for saving resources and energy, since considerable amounts of cast metal could be saved by eliminating ingot cracking, by reducing the scalping thickness of the ingot before rolling, and by eliminating butt sawing. Full-scale industrial implementation of the results of the proposed research would lead to energy savings in excess of 6 trillion Btu by the year 2020. The research undertaken in this project aimed to achieve this objective by a collaboration of industry, university, and national laboratory personnel through Secat, Inc., a consortium of aluminum companies. During the four-year project, the industrial partners and the research team met in 16 quarterly meetings to discuss research results and research direction. The industrial partners provided guidance, facilities, and experience to the research team. The research team went to two industrial plants to measure temperature distributions in commercial 60,000-lb DC casting ingot production. The project focused on the development of a fundamental understanding of ingot cracking and detailed models of thermal conditions, solidification, microstructural evolution, and stress development during the initial transient in DC castings of the aluminum alloys 3004 and 5182. The microstructure of the DC casting ingots was systematically characterized. Carefully designed experiments were carried out at the national laboratory and university facilities as well as at the industrial locations using the industrial production facilities. The advanced computational capabilities of the national laboratories were used for thermodynamic and kinetic simulations of phase transformation, heat transfer and fluid flow, solidification, and stress-strain evolution during DC casting. The achievements of the project are the following: (1) Identified the nature of crack formation during DC casting; (2) Developed a novel method for determining the mechanical properties of an alloy at the nonequilibrium mushy zone of the alloy; (3) Measured heat transfer coefficients (HTCs) between the solidifying ingot and the cooling water jet; (4) Determined the material constitutive model at high temperatures; and (5) Developed computational capabilities for the simulation of cracking formation in DC casting ingot. The models and the database de

  14. SCREENING TESTS FOR IMPROVED METHANE CRACKING MATERIALS

    SciTech Connect (OSTI)

    Klein, J; Jeffrey Holder, J

    2007-07-16T23:59:59.000Z

    Bench scale (1 to 6 gram) methane cracking tests have been performed on a variety of pure elements, some alloys, and SAES{reg_sign} commercial getters St 101, St 198, St 707, St 737, and St 909 to determine methane cracking performance (MCP) of 5% methane in a helium carrier at 700 C, 101.3 kPa (760 torr) with a 10 sccm feed. The MCP was almost absent from some materials tested while others showed varying degrees of MCP. Re, Cr, V, Gd, and Mo powders had good MCP, but limited capacities. Nickel supported on kieselguhr (Ni/k), a Zr-Ni alloy, and the SAES{reg_sign} getters had good MCP in a helium carrier. The MCP of these same materials was suppressed in a hydrogen carrier stream and the MCP of the Zr-based materials was reduced by nitride formation when tested with a nitrogen carrier gas.

  15. Screening tests for improved methane cracking materials

    SciTech Connect (OSTI)

    Klein, J. E.; Hoelder, J. S. [Savannah River National Laboratory, Aiken, SC 29808 (United States)

    2008-07-15T23:59:59.000Z

    Bench scale (1 to 6 gram) methane cracking tests have been performed on a variety of pure elements, some alloys, and SAES{sup R} commercial getters St 101, St 198, St 707, St 737, and St 909 to determine methane cracking performance (MCP) of 5% methane in a helium carrier at 700 deg.C, 101.3 kPa (760 torr) with a 10 seem feed. The MCP was almost absent from some materials tested while others showed varying degrees of MCP. Re, Cr, V, Gd, and Mo powders had good MCP, but limited capacities. Nickel supported on kieselguhr (Ni/k), a Zr-Ni alloy, and the SAESr getters had good MCP in a helium carrier. The MCP of these same materials was suppressed in a hydrogen carrier stream and the MCP of the Zr-based materials was reduced by nitride formation when tested with a nitrogen carrier gas. (authors)

  16. Process for magnetic beneficiating petroleum cracking catalyst

    DOE Patents [OSTI]

    Doctor, R.D.

    1993-10-05T23:59:59.000Z

    A process is described for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded. 1 figures.

  17. Process for magnetic beneficiating petroleum cracking catalyst

    DOE Patents [OSTI]

    Doctor, Richard D. (Lisle, IL)

    1993-01-01T23:59:59.000Z

    A process for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded.

  18. Circumferential cracking of steam generator tubes

    SciTech Connect (OSTI)

    Karwoski, K.J.

    1997-04-01T23:59:59.000Z

    On April 28, 1995, the U.S. Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 95-03, {open_quote}Circumferential Cracking of Steam Generator Tubes.{close_quote} GL 95-03 was issued to obtain information needed to verify licensee compliance with existing regulatory requirements regarding the integrity of steam generator tubes in domestic pressurized-water reactors (PWRs). This report briefly describes the design and function of domestic steam generators and summarizes the staff`s assessment of the responses to GL 95-03. The report concludes with several observations related to steam generator operating experience. This report is intended to be representative of significant operating experience pertaining to circumferential cracking of steam generator tubes from April 1995 through December 1996. Operating experience prior to April 1995 is discussed throughout the report, as necessary, for completeness.

  19. SCATTERING BY CRACKS BENEATH FLUIDSOLID INTERFACES

    E-Print Network [OSTI]

    Craster, Richard

    parameters relevant for water­metal and water­rock combinations are taken and far field scattering patterns the fluid. For line source excitation surface waves are generated that impinge upon defects near the surface with distance along the interface from its source of excitation. The light fluid loading limit is important f

  20. Structures for dense, crack free thin films

    DOE Patents [OSTI]

    Jacobson, Craig P. (Lafayette, CA); Visco, Steven J. (Berkeley, CA); De Jonghe, Lutgard C. (Lafayette, CA)

    2011-03-08T23:59:59.000Z

    The process described herein provides a simple and cost effective method for making crack free, high density thin ceramic film. The steps involve depositing a layer of a ceramic material on a porous or dense substrate. The deposited layer is compacted and then the resultant laminate is sintered to achieve a higher density than would have been possible without the pre-firing compaction step.

  1. Pore fluid effects on seismic velocity in anisotropic rocks

    SciTech Connect (OSTI)

    Mukerji, T.; Mavko, G. (Stanford Univ., CA (United States). Dept. of Geophysics)

    1994-02-01T23:59:59.000Z

    A simple new technique predicts the high- and low-frequency saturated velocities in anisotropic rocks entirely in terms of measurable dry rock properties without the need for idealized crack geometries. Measurements of dry velocity versus pressure and porosity versus pressure contain all of the necessary information for predicting the frequency-dependent effects of fluid saturation. Furthermore, these measurements automatically incorporate all pore interaction, so there is no limitation to low crack density. The velocities are found to depend on five key interrelated variables: frequency, the distribution of compliant crack-like porosity, the intrinsic or noncrack anisotropy, fluid viscosity and compressibility, and effective pressure. The sensitivity of velocities to saturation is generally greater at high frequencies than low frequencies. The magnitude of the differences from dry to saturated and from low frequency to high frequency is determined by the compliant or crack-like porosity. Predictions of saturated velocities based on dry data for sandstone and granite show that compressional velocities generally increase with saturation and with frequency. However, the degree of compressional wave anisotropy may either increase or decrease upon saturation depending on the crack distribution, the effective pressure, and the frequency at which the measurements are made. Shear-wave velocities can either increase or decrease with saturation, and the degree of anisotropy depends on the microstructure, pressure, and frequency. Consequently great care must be taken when interpreting observed velocity anisotropy for measurements at low frequencies, typical of in situ observations, will generally be different from those at high frequencies, typical of the laboratory.

  2. Catalytic Consequences of Acid Strength in the Conversion of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Consequences of Acid Strength in the Conversion of Methanol to Dimethyl Ether. Catalytic Consequences of Acid Strength in the Conversion of Methanol to Dimethyl Ether. Abstract:...

  3. Catalyst Cartography: 3D Super-Resolution Mapping of Catalytic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    an individual catalytic nanoparticle while reactions are occurring. Catalysts are used in manufacturing everything from stain remover to rocket fuel; they make production more...

  4. Improved Low-Temperature Performance of Catalytic Converters...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Catalytic converters, installed on vehicles with internal combustion and diesel engines, convert the toxic byproducts of combustion to less toxic compounds. In two-way (lean...

  5. Catalytic reduction system for oxygen-rich exhaust

    DOE Patents [OSTI]

    Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

    1999-04-13T23:59:59.000Z

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

  6. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway...

    Broader source: Energy.gov (indexed) [DOE]

    the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium...

  7. The Effects of Trace Contaminants on Catalytic Processing of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Processing of Biomass-Derived Feedstocks . Abstract: Trace components in biomass feedstocks are potential catalyst poisons when catalytically processing these materials to...

  8. Application of the cracked pipe element to creep crack growth prediction

    SciTech Connect (OSTI)

    Brochard, J.; Charras, T. [C.E.A.-C.E.-Saclay DRN/DMT, Gif Sur Yvette (France); Ghoudi, M. [C.E.A.-C.E.-Saclay, Gif Sur Yvette (France)

    1997-04-01T23:59:59.000Z

    Modifications to a computer code for ductile fracture assessment of piping systems with postulated circumferential through-wall cracks under static or dynamic loading are very briefly described. The modifications extend the capabilities of the CASTEM2000 code to the determination of fracture parameters under creep conditions. The main advantage of the approach is that thermal loads can be evaluated as secondary stresses. The code is applicable to piping systems for which crack propagation predictions differ significantly depending on whether thermal stresses are considered as primary or secondary stresses.

  9. Catalytic multi-stage liquefaction (CMSL)

    SciTech Connect (OSTI)

    Comolli, A.G.; Ganguli, P.; Karolkiewicz, W.F.; Lee, T.L.K.; Pradhan, V.R.; Popper, G.A.; Smith, T.; Stalzer, R.

    1996-11-01T23:59:59.000Z

    Under contract with the U.S. Department of Energy, Hydrocarbon Technologies, Inc. has conducted a series of eleven catalytic, multi-stage, liquefaction (CMSL) bench scale runs between February, 1991, and September, 1995. The purpose of these runs was to investigate novel approaches to liquefaction relating to feedstocks, hydrogen source, improved catalysts as well as processing variables, all of which are designed to lower the cost of producing coal-derived liquid products. This report summarizes the technical assessment of these runs, and in particular the evaluation of the economic impact of the results.

  10. Thin film porous membranes for catalytic sensors

    SciTech Connect (OSTI)

    Hughes, R.C.; Boyle, T.J.; Gardner, T.J. [and others

    1997-06-01T23:59:59.000Z

    This paper reports on new and surprising experimental data for catalytic film gas sensing resistors coated with nanoporous sol-gel films to impart selectivity and durability to the sensor structure. This work is the result of attempts to build selectivity and reactivity to the surface of a sensor by modifying it with a series of sol-gel layers. The initial sol-gel SiO{sub 2} layer applied to the sensor surprisingly showed enhanced O{sub 2} interaction with H{sub 2} and reduced susceptibility to poisons such as H{sub 2}S.

  11. Catalytic Solutions Inc CSI | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomassSustainableCSLInformationMissouri:Catalyst Regeneration MarketCatalytic

  12. BioCatalytics | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia: EnergyAvignon,Belcher Homes JumpMaintenance |BigBigLakeBioCatalytics

  13. CYCLIC PLASTICITY OF A CRACKED STRUCTURE SUBJECTED TO MIXED MODE LOADING

    E-Print Network [OSTI]

    CYCLIC PLASTICITY OF A CRACKED STRUCTURE SUBJECTED TO MIXED MODE LOADING Sylvie Pommier1, a 1 LMT, mixed mode crack propagation, plasticity, crack deflection. Abstract. Cyclic plasticity in the crack tip stresses in the overload's plastic zone. Moreover, if the overload's ratio is large enough, the crack may

  14. amplitude fatigue crack: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rate testing to evaluate the susceptibility of metallic materials to environmentally assisted cracking CERN Preprints Summary: 1.1 This practice covers procedures for the design,...

  15. assisted cracking resistance: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    video system, crack initiation, propagation, and ... Miller, James Thomas, Ph. D. Massachusetts Institute of Technology 2008-01-01 36 Dynamic fracture of compositionally...

  16. alligator cracking: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    video system, crack initiation, propagation, and ... Miller, James Thomas, Ph. D. Massachusetts Institute of Technology 2008-01-01 40 A new alligator-clip compound for...

  17. P wave anisotropy, stress, and crack distribution at Coso geothermal...

    Open Energy Info (EERE)

    Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: P wave anisotropy, stress, and crack distribution at Coso geothermal field, California...

  18. High-Resolution Crack Imaging Reveals Degradation Processes in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Reveals Degradation Processes in Nuclear Reactor Structural Materials. Abstract: Corrosion and cracking represent critical failure mechanisms for structural materials in many...

  19. Tribological Analysis of White Etching Crack (WEC) Failures in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Crack (WEC) Failures in Rolling Element Bearings Presented by Arnaud Ruellan, INSA de Lyon at the Wind Turbine Tribology Seminar 2014. 20141030NREL2014ArgonneRuellancomV...

  20. NORTHWESTERN UNIVERSITY Qualification of Autonomous Crack Monitoring Systems

    E-Print Network [OSTI]

    NORTHWESTERN UNIVERSITY Qualification of Autonomous Crack Monitoring Systems A Thesis Submitted Term or Static Testing Equipment Setup.............................................29 Long Term Response.....................................................................33 Dynamic Testing Equipment

  1. Standardization of Thermo-Fluid Modeling in Modelica.Fluid

    E-Print Network [OSTI]

    Franke, Rudiger

    2010-01-01T23:59:59.000Z

    Thermo-Fluid Systems, Modelica 2003 Conference, Linköping,H. Tummescheit: The Modelica Fluid and Media Library forThermo-Fluid Pipe Networks, Modelica 2006 Conference, Vi-

  2. Catalytic cracking of n-Dodecane and Alkyl benzenes over FCC Zeolite Catalysts: Time on Stream and Reactant Converted Models

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    hydrocarbon model compounds (n-dodecane, 1,3,5- triisopropylbenzene, and 1,4-diisopropylbenzene) has been investigated over two FCC zeolite catalysts in a novel riser simulator that resembles closely the operating compounds. This can be due to the smaller ZSM-5 pore diameter (in the range of 5-6 Å) that restricts alkyl

  3. Crack opening area estimates in pressurized through-wall cracked elbows under bending

    SciTech Connect (OSTI)

    Franco, C.; Gilles, P.; Pignol, M.

    1997-04-01T23:59:59.000Z

    One of the most important aspects in the leak-before-break approach is the estimation of the crack opening area corresponding to potential through-wall cracks at critical locations during plant operation. In order to provide a reasonable lower bound to the leak area under such loading conditions, numerous experimental and numerical programs have been developed in USA, U.K. and FRG and widely discussed in literature. This paper aims to extend these investigations on a class of pipe elbows characteristic of PWR main coolant piping. The paper is divided in three main parts. First, a new simplified estimation scheme for leakage area is described, based on the reference stress method. This approach mainly developed in U.K. and more recently in France provides a convenient way to account for the non-linear behavior of the material. Second, the method is carried out for circumferential through-wall cracks located in PWR elbows subjected to internal pressure. Finite element crack area results are presented and comparisons are made with our predictions. Finally, in the third part, the discussion is extended to elbows under combined pressure and in plane bending moment.

  4. Cracking in reinforced concrete bent caps

    E-Print Network [OSTI]

    Young, Bradley S.

    2000-01-01T23:59:59.000Z

    ) . . . . . . . . . . . . . . . . 4. 2 Group It2 Response (Specimens 3C, 3D, 4C, 4E, 5D, 5E) . . . 4. 3 Group tt3 Response (Specimens 6F, 6G, 7F, 7H, 8G, 8H) . . . 4. 4 General Response 4. 5 Sununary. . . . . 49 . . . . 58 . . . . 64 70 . . . 75 5. STRUT-AND-TIE MODELING... be expressed as the product of the steel strain (s, ) at that level multiplied by the crack spacing (s, ); 20 w =z*s C S C (2. 6) a linear strain gradient can be used to project the maximum strain occurring at the level of the flexural reinforcement...

  5. 3:2:1 Crack Spread

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Year-0E (2001)gasoline prices4 Oil demand8)Commercial5 1:2:1 Crack

  6. Ability of Catalytic Converters to Reduce Air Pollution

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    NOx - 1 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST Last updated: June 17, 2014 #12;NOx - 2 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST INTRODUCTION Automobile engines

  7. Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion

    SciTech Connect (OSTI)

    Zhang, Lingzhi; Wei, Wei; Manke, Jeff; Vazquez, Arturo; Thompson, Jeff; Thompson, Mark

    2011-05-28T23:59:59.000Z

    Biomass gasification is a flexible and efficient way of utilizing widely available domestic renewable resources. Syngas from biomass has the potential for biofuels production, which will enhance energy security and environmental benefits. Additionally, with the successful development of low Btu fuel engines (e.g. GE Jenbacher engines), syngas from biomass can be efficiently used for power/heat co-generation. However, biomass gasification has not been widely commercialized because of a number of technical/economic issues related to gasifier design and syngas cleanup. Biomass gasification, due to its scale limitation, cannot afford to use pure oxygen as the gasification agent that used in coal gasification. Because, it uses air instead of oxygen, the biomass gasification temperature is much lower than well-understood coal gasification. The low temperature leads to a lot of tar formation and the tar can gum up the downstream equipment. Thus, the biomass gasification tar removal is a critical technology challenge for all types of biomass gasifiers. This USDA/DOE funded program (award number: DE-FG36-O8GO18085) aims to develop an advanced catalytic tar conversion system that can economically and efficiently convert tar into useful light gases (such as syngas) for downstream fuel synthesis or power generation. This program has been executed by GE Global Research in Irvine, CA, in collaboration with Professor Lanny Schmidt's group at the University of Minnesota (UoMn). Biomass gasification produces a raw syngas stream containing H2, CO, CO2, H2O, CH4 and other hydrocarbons, tars, char, and ash. Tars are defined as organic compounds that are condensable at room temperature and are assumed to be largely aromatic. Downstream units in biomass gasification such as gas engine, turbine or fuel synthesis reactors require stringent control in syngas quality, especially tar content to avoid plugging (gum) of downstream equipment. Tar- and ash-free syngas streams are a critical requirement for commercial deployment of biomass-based power/heat co-generation and biofuels production. There are several commonly used syngas clean-up technologies: (1) Syngas cooling and water scrubbing has been commercially proven but efficiency is low and it is only effective at small scales. This route is accompanied with troublesome wastewater treatment. (2) The tar filtration method requires frequent filter replacement and solid residue treatment, leading to high operation and capital costs. (3) Thermal destruction typically operates at temperatures higher than 1000oC. It has slow kinetics and potential soot formation issues. The system is expensive and materials are not reliable at high temperatures. (4) In-bed cracking catalysts show rapid deactivation, with durability to be demonstrated. (5) External catalytic cracking or steam reforming has low thermal efficiency and is faced with problematic catalyst coking. Under this program, catalytic partial oxidation (CPO) is being evaluated for syngas tar clean-up in biomass gasification. The CPO reaction is exothermic, implying that no external heat is needed and the system is of high thermal efficiency. CPO is capable of processing large gas volume, indicating a very compact catalyst bed and a low reactor cost. Instead of traditional physical removal of tar, the CPO concept converts tar into useful light gases (eg. CO, H2, CH4). This eliminates waste treatment and disposal requirements. All those advantages make the CPO catalytic tar conversion system a viable solution for biomass gasification downstream gas clean-up. This program was conducted from October 1 2008 to February 28 2011 and divided into five major tasks. - Task A: Perform conceptual design and conduct preliminary system and economic analysis (Q1 2009 ~ Q2 2009) - Task B: Biomass gasification tests, product characterization, and CPO tar conversion catalyst preparation. This task will be conducted after completing process design and system economics analysis. Major milestones include identification of syngas cleaning requirements for proposed system

  8. Fluid sampling tool

    DOE Patents [OSTI]

    Johnston, Roger G. (Los Alamos, NM); Garcia, Anthony R. E. (Espanola, NM); Martinez, Ronald K. (Santa Cruz, NM)

    2001-09-25T23:59:59.000Z

    The invention includes a rotatable tool for collecting fluid through the wall of a container. The tool includes a fluid collection section with a cylindrical shank having an end portion for drilling a hole in the container wall when the tool is rotated, and a threaded portion for tapping the hole in the container wall. A passageway in the shank in communication with at least one radial inlet hole in the drilling end and an opening at the end of the shank is adapted to receive fluid from the container. The tool also includes a cylindrical chamber affixed to the end of the shank opposite to the drilling portion thereof for receiving and storing fluid passing through the passageway. The tool also includes a flexible, deformable gasket that provides a fluid-tight chamber to confine kerf generated during the drilling and tapping of the hole. The invention also includes a fluid extractor section for extracting fluid samples from the fluid collecting section.

  9. Viscous fluid dynamics

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2007-03-12T23:59:59.000Z

    We briefly discuss the phenomenological theory of dissipative fluid. We also present some numerical results for hydrodynamic evolution of QGP fluid with dissipation due to shear viscosity only. Its effect on particle production is also studied.

  10. HEAT TRANSFER FLUIDS

    E-Print Network [OSTI]

    Lenert, Andrej

    2012-01-01T23:59:59.000Z

    The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

  11. A nanomechanical investigation of the crack tip process zone of marble

    E-Print Network [OSTI]

    Brooks, Zenzile (Zenzile Z.)

    2010-01-01T23:59:59.000Z

    This study explores the interaction between crack initiation and nanomechanical properties in the crack tip process zone (zone of microcracking at the tip of a propagating crack) of a brittle geomaterial. Samples of Carrara ...

  12. The displacement field characterization of two interacting parallel edge cracks in a finite body

    E-Print Network [OSTI]

    Keener, Todd Whitney

    1996-01-01T23:59:59.000Z

    The goals of this research were to: (1) develop a model to represent the displacement field surrounding two interacting, parallel edge cracks; and (2) use this model to investigate the influence of crack separation and relative crack length...

  13. Standardization of Thermo-Fluid Modeling in Modelica.Fluid

    E-Print Network [OSTI]

    Franke, Rudiger

    2010-01-01T23:59:59.000Z

    Ob- ject-Oriented Modeling of Thermo-Fluid Systems, Modelicable and Compressible Thermo-Fluid Pipe Networks, ModelicaStandardization of Thermo-Fluid Modeling in Modelica.Fluid

  14. Preparation and characterization of VOx/TiO2 catalytic coatings on stainless steel plates for structured catalytic reactors.

    E-Print Network [OSTI]

    Boyer, Edmond

    for structured catalytic reactors. Thierry Giornelli, Axel Löfberg* and Elisabeth Bordes-Richard Unité de.Lofberg@univ-lille1.fr Abstract The parameters to be controlled to coat metallic walls by VOx/TiO2 catalysts which) was chosen because of its large application in industrial catalytic reactors. TiO2 films on stainless steel

  15. View dependent fluid dynamics

    E-Print Network [OSTI]

    Barran, Brian Arthur

    2006-08-16T23:59:59.000Z

    , are modified to support a nonuniform simulation grid. In addition, infinite fluid boundary conditions are introduced that allow fluid to flow freely into or out of the simulation domain to achieve the effect of large, boundary free bodies of fluid. Finally, a...

  16. Field Manual for Crack Sealing in Asphalt Pavements

    E-Print Network [OSTI]

    Texas at Austin, University of

    Field Manual for Crack Sealing in Asphalt Pavements Yetkin Yildirim, Ahmed Qatan, and Jorge Prozzi January 2006 3208RedRiver Austin,TX78705 #12;Dr. Yetkin Yildirim, P.E. Director Texas Pavement for Crack Sealing in Asphalt Pavements #12;Performing Organization: Center for Transportation Research

  17. NORTHWESTERN UNIVERSITY Crack Response to Weather Effects, Blasting, and Construction

    E-Print Network [OSTI]

    NORTHWESTERN UNIVERSITY Crack Response to Weather Effects, Blasting, and Construction Vibrations Acknowledgements iii Abstract iv List of Figures v List of Tables xi Chapter 1- Introduction 1 Chapter 2- Blast Vibration Response, Southbury, Connecticut 5 Structural Description Instrumentation Blast Response Crack

  18. Crack-based analysis of concrete with brittle reinforcement

    E-Print Network [OSTI]

    Burgoyne, Chris

    { FaberMaunsell Ltd; University of Cambridge Brittle reinforcement (such as fibre-reinforced plastic to the surround- ing concrete, at a crack surface sL=sR s on the left/right side of a crack u increase in unbonded

  19. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, E.M. Jr.

    1984-03-27T23:59:59.000Z

    A method is described for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor, contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

  20. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, E.M. Jr.

    1985-08-20T23:59:59.000Z

    A method and apparatus are disclosed for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

  1. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, Jr., Edward M. (Friendswood, TX)

    1984-01-01T23:59:59.000Z

    A method for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catatlyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

  2. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, Jr., Edward M. (Friendswood, TX)

    1985-01-01T23:59:59.000Z

    A method and apparatus for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

  3. Catalytic cartridge SO/sub 3/ decomposer

    DOE Patents [OSTI]

    Galloway, T.R.

    1980-11-18T23:59:59.000Z

    A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO/sub 3/ decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO/sub 3/ gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO/sub 3/ gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety. A fusion reactor may be used as the heat source.

  4. Catalytic carbon membranes for hydrogen production

    SciTech Connect (OSTI)

    Damle, A.S.; Gangwal, S.K.

    1992-01-01T23:59:59.000Z

    Commercial carbon composite microfiltration membranes may be modified for gas separation applications by providing a gas separation layer with pores in the 1- to 10-nm range. Several organic polymeric precursors and techniques for depositing a suitable layer were investigated in this project. The in situ polymerization technique was found to be the most promising, and pure component permeation tests with membrane samples prepared with this technique indicated Knudsen diffusion behavior. The gas separation factors obtained by mixed-gas permeation tests were found to depend strongly on gas temperature and pressure indicating significant viscous flow at high-pressure conditions. The modified membranes were used to carry out simultaneous water gas shift reaction and product hydrogen separation. These tests indicated increasing CO conversions with increasing hydrogen separation. A simple process model was developed to simulate a catalytic membrane reactor. A number of simulations were carried out to identify operating conditions leading to product hydrogen concentrations over 90 percent. (VC)

  5. Experimental Verification of a Cracked Fuel Mechanical Model

    SciTech Connect (OSTI)

    Williford, R. E.

    1982-12-01T23:59:59.000Z

    This report describes the results of a series of laboratory experiments conducted to independently verify a model that describes the nonlinear mechanical behavior of cracked fuel in pelletized UO{sub 2}/Zircaloy nuclear fuel rods under normal operating conditions. After a brief description of the analytical model, each experiment is discussed in detail. Experiments were conducted to verify the general behavior and numerical values for the three primary independent modelling parameters (effective crack roughness, effective gap roughness, and total crack length), and to verify the model predictions that the effective Young's moduli for cracked fuel systems were substantially less than those for solid UO{sub 2} pellets. In general, the model parameters and predictions were confirmed, and new insight was gained concerning the complexities of cracked fuel mechanics.

  6. SciTech Connect: Stress corrosion cracking of alloy 600 using...

    Office of Scientific and Technical Information (OSTI)

    Stress corrosion cracking of alloy 600 using the constant strain rate test Citation Details In-Document Search Title: Stress corrosion cracking of alloy 600 using the constant...

  7. A Crack in the Pipeline: Why Female Underrepresented Racial Minority Students Leave Engineering

    E-Print Network [OSTI]

    Vazquez-Akim, Jenn

    2014-01-01T23:59:59.000Z

    Espinosa, Lorelle L. (2011). Pipelines and pathways: womenAngeles A Crack in the Pipeline: Why Female UnderrepresentedA Crack in the Pipeline: Why Female Underrepresented Racial

  8. Spinning fluids reactor

    SciTech Connect (OSTI)

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20T23:59:59.000Z

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  9. Fluid Dynamics Seminar Fluid Dynamics Research Centre

    E-Print Network [OSTI]

    Davies, Christopher

    France) 8th Nov. Future Trends in Condition Monitoring of Rotating Machines Using System Identification Simulation of the Cooling of a Simplified Brake Disc Dr. Thorsten J. Möller, (Institute for Fluid Mechanics

  10. Fluid Dynamics Seminar Fluid Dynamics Research Centre

    E-Print Network [OSTI]

    Thomas, Peter J.

    France) 8 th Nov. Future Trends in Condition Monitoring of Rotating Machines Using System Identification Simulation of the Cooling of a Simplified Brake Disc Dr. Thorsten J. Möller, (Institute for Fluid Mechanics

  11. J. Fluid Mech. (2011), vol. 672, pp. 6077. c Cambridge University Press 2011 doi:10.1017/S0022112010005860

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    2011-01-01T23:59:59.000Z

    of hydraulic fracturing techniques is commonplace in enhancing the recovery of oil and gas (Desroches et al, it is shown how these fronts converge to zero-toughness fracture solutions with a genuine crack tip of advancing fluid contact lines. Experiments are conducted using a block of gelatin for the solid and golden

  12. Heat transfer rates in fixed bed catalytic reactors

    E-Print Network [OSTI]

    Levelton, Bruce Harding

    1951-01-01T23:59:59.000Z

    HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS H EATTRNSFSAIX DB DNCLR YFNOAXa rRJRuSIX nSeR 1951i HssNIJFu FT SI TSBuR FXO LIXSRXS NRLIeeRXOROt HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS H EATTRNSFSAIX BSar DNCLR YFNOAXa r...RJRuSIX June 1951 HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS A Dissertation Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

  13. Implications of early stages in the growth of stress corrosion cracking on component reliability

    SciTech Connect (OSTI)

    Jones, R.H.; Simonen, E.P.

    1995-04-01T23:59:59.000Z

    Environment-induced crack growth generally progresses through several stages prior to component failure. Crack initiation, short crack growth, and stage 1 growth are early stages in crack development that are summarized in this paper. The implications of these stages on component reliability, derive from the extended time that the crack exists in the early stages because crack velocity is slow. The duration of the early stages provides a greater opportunity for corrective action if cracks can be detected. Several important factors about the value of understanding short crack behavior include: (1) life prediction requires a knowledge of the total life cycle of the crack including the early stages, (2) greater reliability is possible if the transition between short and long crack behavior is known component life after this transition is short and (3) remedial actions are more effective for short than long cracks.

  14. Reliability of steam generator tubes with axial cracks

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B. [Jozef Stefan Inst., Ljubljana (Slovenia). Reactor Engineering Div.; Vencelj, P. [Univ. of Ljubljana (Slovenia). Faculty of Mathematics and Physics

    1996-11-01T23:59:59.000Z

    An approach for estimating the failure probability of tubes containing through-wall axial cracks has already been proposed by the authors. It is based on probabilistic fracture mechanics and accounts for scatter in tube geometry and material properties, scatter in residual and operational stresses responsible for crack propagation, and characteristics of nondestructive examination and plugging procedures (e.g., detection probability, sizing accuracy, human errors). Results of preliminary tests demonstrated wide applicability of this approach and triggered some improvements. The additions to the model are extensively discussed in this paper. Capabilities are demonstrated by results of analysis of steam generator no. 1 in Slovenian nuclear power plant located in Krsko after the 1992 inspection and plugging campaign. First, the number of cracked tubes and the crack length distribution were estimated using data obtained by the 100% motorized pancake coil inspection. The inspection and plugging activities were simulated in the second step to estimate the efficiency of maintenance in terms of single and multiple-tube rupture probabilities. They were calculated as a function of maximum allowable crack length. The importance of human errors and some limitations of present nondestructive examination techniques were identified. The traditional wall thickness and crack-length-based plugging criteria are compared. The crack-length-based criterion is shown to be more efficient and more safe, especially because of strong suppression effect on probability of multiple-tube rupture. The results are considered to be important for safety and maintenance of existing plants and for further research.

  15. Standard test method for creep-fatigue crack growth testing

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01T23:59:59.000Z

    1.1 This test method covers the determination of creep-fatigue crack growth properties of nominally homogeneous materials by use of pre-cracked compact type, C(T), test specimens subjected to uniaxial cyclic forces. It concerns fatigue cycling with sufficiently long loading/unloading rates or hold-times, or both, to cause creep deformation at the crack tip and the creep deformation be responsible for enhanced crack growth per loading cycle. It is intended as a guide for creep-fatigue testing performed in support of such activities as materials research and development, mechanical design, process and quality control, product performance, and failure analysis. Therefore, this method requires testing of at least two specimens that yield overlapping crack growth rate data. The cyclic conditions responsible for creep-fatigue deformation and enhanced crack growth vary with material and with temperature for a given material. The effects of environment such as time-dependent oxidation in enhancing the crack growth ra...

  16. New Clean Coal Cycle Optimized Using Pinch Technology 

    E-Print Network [OSTI]

    Rossiter, A. P.; O'Donnell, J. J.

    1990-01-01T23:59:59.000Z

    transport reaction technology, developed originally for Fluid Catalytic Cracking plants, is used in the coal conversion steps; and pulverized limestone is circulated with the coal to capture the sulfur that is released during this process. Both gas turbines...

  17. Peer Reviewed Archival Publications

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    -176. Bayraktar* , O. and E.L. Kugler. 2002. Characterization of coke on equilibrium fluid-catalytic- cracking. Characteristics and carbonization behaviors of coal extracts. Fuel Processing Technology 79: 207-215. Stiller, A

  18. nature chemistry | VOL 1 | APRIL 2009 | www.nature.com/naturechemistry 37 review article

    E-Print Network [OSTI]

    Southern California, University of

    : about half of all petrol in the world is now produced by fluid catalytic cracking using specially-way catalyst installed in most petrol-fuelled passenger cars. Moreover, these developments have contributed

  19. Control of Substrate Access to the Active Site and Catalytic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Control of Substrate Access to the Active Site and Catalytic Mechanism of Methane and Toluene Monooxygenases Friday, June 22, 2012 - 3:30pm SSRL Main Conference Room 137-322 Prof....

  20. Hydrogen permeable protective coating for a catalytic surface

    DOE Patents [OSTI]

    Liu, Ping (Irvine, CA); Tracy, C. Edwin (Golen, CO); Pitts, J. Roland (Lakewood, CO); Lee, Se-Hee (Lakewood, CO)

    2007-06-19T23:59:59.000Z

    A protective coating for a surface comprising a layer permeable to hydrogen, said coating being deposited on a catalyst layer; wherein the catalytic activity of the catalyst layer is preserved.

  1. Emerging catalytic processes for the production of adipic acid

    E-Print Network [OSTI]

    Van de Vyver, Stijn

    Research efforts to find more sustainable pathways for the synthesis of adipic acid have led to the introduction of new catalytic processes for producing this commodity chemical from alternative resources. With a focus on ...

  2. Catalytic H2O2 decomposition on palladium surfaces

    E-Print Network [OSTI]

    Salinas, S. Adriana

    1998-01-01T23:59:59.000Z

    The catalytic decomposition of H?O? at smooth single-crystal and polycrystalline palladium surfaces that had been subjected to various surface modifications has been studied. Monolayer and submonolayer coverages of I, Br and Cl adsorbates were used...

  3. An Energy Analysis of the Catalytic Combustion Burner

    E-Print Network [OSTI]

    Dong, Q.; Zhang, S.; Duan, Z.; Zhou, Q.

    2006-01-01T23:59:59.000Z

    The gas boilers of conventional flame always produce varying degrees of combustion products NOx and CO, which pollute the environment and waste energy. As a new way of combustion, catalytic combustion breaks the flammable limits of conventional...

  4. In situ XAS Characterization of Catalytic Nano-Materials with...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    XAS Characterization of Catalytic Nano-Materials with Applications to Fuel Cells and Batteries Friday, July 12, 2013 - 11:00am SLAC, Conference Room 137-322 Presented by Qingying...

  5. atp catalytic domain: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 328 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  6. acidic multimetallic catalytic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 106 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  7. automobile catalytic converters: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Odei 2006-01-01 408 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  8. atp catalytic cycle: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 275 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  9. advanced catalytic hydrogenation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 188 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  10. apparent catalytic site: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 257 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  11. advanced catalytic materials: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 225 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  12. acrylamide catalytically inhibits: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 78 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  13. assisted catalytic oxidation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 251 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  14. active catalytic sites: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 337 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  15. atpase catalytic domain: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 266 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  16. advanced catalytic materials 1996: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 467 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  17. archaeal primase catalytic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 92 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  18. advanced catalytic science: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produc Kik, Pieter 488 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  19. Catalytic studies of supported Pd-Au catalysts 

    E-Print Network [OSTI]

    Boopalachandran, Praveenkumar

    2006-08-16T23:59:59.000Z

    Although Pd-Au high-surface area catalysts are used in industry to improve activity and selectivity, a thorough understanding of the nature of these enhancements is lacking. A molecular-level understanding of catalytic ...

  20. Catalytic Membrane Reactor for Extraction of Hydrogen from Bioethanol Reforming

    E-Print Network [OSTI]

    Kuncharam, Bhanu Vardhan

    2013-11-26T23:59:59.000Z

    This research explores a novel application of catalytic membrane reactors for high- purity hydrogen extraction from bioethanol reforming. Conventional membrane systems employ hydrogen permselective materials such as palladium, polymer membranes...

  1. Prediction of thermal reflection cracking in west Texas

    E-Print Network [OSTI]

    Chang, Hang-Sun

    1975-01-01T23:59:59.000Z

    for the stress intensity factor, Ck, following Barenblatt (53) is used. z 'e(')4' C = ? / k n o (3-11) where C is the distance away from crack tip and o (g) is the surface e stress inside the crack tip element, i. e. ? o is the thermal stress at the depth... of the studies being conducted on pavement temp- erature cracking have been mainly concerned with the fracture suscepti- bilityy of asphalt concrete under extremely low temperature (3, 4). Find- ings of these studies could not provide satisfactory...

  2. Disposal of drilling fluids

    SciTech Connect (OSTI)

    Bryson, W.R.

    1983-06-01T23:59:59.000Z

    Prior to 1974 the disposal of drilling fluids was not considered to be much of an environmental problem. In the past, disposal of drilling fluids was accomplished in various ways such as spreading on oil field lease roads to stabilize the road surface and control dust, spreading in the base of depressions of sandy land areas to increase water retention, and leaving the fluid in the reserve pit to be covered on closure of the pit. In recent years, some states have become concerned over the indescriminate dumping of drilling fluids into pits or unauthorized locations and have developed specific regulations to alleviate the perceived deterioration of environmental and groundwater quality from uncontrolled disposal practices. The disposal of drilling fluids in Kansas is discussed along with a newer method or treatment in drilling fluid disposal.

  3. Fiber optic fluid detector

    DOE Patents [OSTI]

    Angel, S.M.

    1987-02-27T23:59:59.000Z

    Particular gases or liquids are detected with a fiber optic element having a cladding or coating of a material which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses. 10 figs.

  4. Multiphase Equilibrium of Fluids Confined in Fisher-Tropsch Catalytic Systems

    E-Print Network [OSTI]

    Warrag, Samah

    2014-04-23T23:59:59.000Z

    . Although this technology was discovered in 1923, commercialization and scale up are limited to the use of few reactor configurations (e.g. multi-tubular fixed-bed reactor, Slurry-bubble column reactor, and fluidized bed reactors). In order to improve...

  5. Northwestern University Facility for Clean Catalytic Process Research

    SciTech Connect (OSTI)

    Marks, Tobin Jay [Northwestern University

    2013-05-08T23:59:59.000Z

    Northwestern University with DOE support created a Facility for Clean Catalytic Process Research. This facility is designed to further strengthen our already strong catalysis research capabilities and thus to address these National challenges. Thus, state-of-the art instrumentation and experimentation facility was commissioned to add far greater breadth, depth, and throughput to our ability to invent, test, and understand catalysts and catalytic processes, hence to improve them via knowledge-based design and evaluation approaches.

  6. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

    SciTech Connect (OSTI)

    Biddy, M.; Jones, S.

    2013-03-01T23:59:59.000Z

    This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway to be competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks have been identified.

  7. Metalworking and machining fluids

    DOE Patents [OSTI]

    Erdemir, Ali (Naperville, IL); Sykora, Frank (Caledon, ON, CA); Dorbeck, Mark (Brighton, MI)

    2010-10-12T23:59:59.000Z

    Improved boron-based metal working and machining fluids. Boric acid and boron-based additives that, when mixed with certain carrier fluids, such as water, cellulose and/or cellulose derivatives, polyhydric alcohol, polyalkylene glycol, polyvinyl alcohol, starch, dextrin, in solid and/or solvated forms result in improved metalworking and machining of metallic work pieces. Fluids manufactured with boric acid or boron-based additives effectively reduce friction, prevent galling and severe wear problems on cutting and forming tools.

  8. Catalytic pyrolysis using UZM-39 aluminosilicate zeolite

    DOE Patents [OSTI]

    Nicholas, Christpher P; Boldingh, Edwin P

    2013-12-17T23:59:59.000Z

    A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and show to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hyrdocarbons into hydrocarbons removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  9. Catalytic pyrolysis using UZM-39 aluminosilicate zeolite

    DOE Patents [OSTI]

    Nicholas, Christopher P; Boldingh, Edwin P

    2014-10-07T23:59:59.000Z

    A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and shown to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub.1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hydrocarbons into hydrocarbons and removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  10. Microchannel Reactor System for Catalytic Hydrogenation

    SciTech Connect (OSTI)

    Adeniyi Lawal; Woo Lee; Ron Besser; Donald Kientzler; Luke Achenie

    2010-12-22T23:59:59.000Z

    We successfully demonstrated a novel process intensification concept enabled by the development of microchannel reactors, for energy efficient catalytic hydrogenation reactions at moderate temperature, and pressure, and low solvent levels. We designed, fabricated, evaluated, and optimized a laboratory-scale microchannel reactor system for hydrogenation of onitroanisole and a proprietary BMS molecule. In the second phase of the program, as a prelude to full-scale commercialization, we designed and developed a fully-automated skid-mounted multichannel microreactor pilot plant system for multiphase reactions. The system is capable of processing 1 – 10 kg/h of liquid substrate, and an industrially relevant immiscible liquid-liquid was successfully demonstrated on the system. Our microreactor-based pilot plant is one-of-akind. We anticipate that this process intensification concept, if successfully demonstrated, will provide a paradigm-changing basis for replacing existing energy inefficient, cost ineffective, environmentally detrimental slurry semi-batch reactor-based manufacturing practiced in the pharmaceutical and fine chemicals industries.

  11. Adsorption Kinetics of Surfactants at Fluid-Fluid Interfaces

    E-Print Network [OSTI]

    Andelman, David

    Adsorption Kinetics of Surfactants at Fluid-Fluid Interfaces Haim Diamant and David Andelman School-Fluid Interfaces, Adsorption, Adsorption Kinetics, Interfacial Tension. 1 #12;Abstract We review a new theoretical approach to the kinetics of surfactant adsorption at fluid-fluid interfaces. It yields a more complete

  12. Dynamics of fluid-filled gelatin cracks www.math.utwente.nl/bokhoveo/

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    of relevance to geology and industry. Geology: magma dike and conduit formation in San Rafael Volcanic field, and Shimabara-Beppu Graben: dike-rock-fault interactions. Industry: enhanced oil-recovery, CO2-sequestration, mining: dike-rock-tunnel interactions? #12;Geology: San Rafael Volcanic fields, Utah Volcanic plumbing

  13. PLASMA Approximate Dynamic Programming finally cracks the locomotive optimization problem

    E-Print Network [OSTI]

    Powell, Warren B.

    PLASMA ­ Approximate Dynamic Programming finally cracks the locomotive optimization problem schedules and new operating policies. PLASMA is currently running at Norfolk Southern for strategic of PLASMA: Each locomotive is modeled individually, making it possible to capture both horsepower

  14. Automated crack control analysis for concrete pavement construction

    E-Print Network [OSTI]

    Jang, Se Hoon

    2005-11-01T23:59:59.000Z

    The focus of this research is on the control of random cracking in concrete paving by using sawcut notch locations in the early stages of construction. This is a major concern in concrete pavement construction. This research also addresses a...

  15. Shear-wave splitting and reservoir crack characterization: the...

    Open Energy Info (EERE)

    Shear-wave splitting and reservoir crack characterization: the Coso geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Shear-wave...

  16. Climate change: A crack in the natural-gas bridge

    E-Print Network [OSTI]

    Davis, SJ; Shearer, C

    2014-01-01T23:59:59.000Z

    J. D. & Wirth, T. E. Natural Gas: A Bridge Fuel for the 21stexpanding supplies of natural gas will not help us to avoidLIM ATE CHANGE A crack in the natural-gas bridge Integrated

  17. A crack in the natural-gas bridge

    E-Print Network [OSTI]

    Davis, SJ; Shearer, C

    2014-01-01T23:59:59.000Z

    J. D. & Wirth, T. E. Natural Gas: A Bridge Fuel for the 21stexpanding supplies of natural gas will not help us to avoidLIM ATE CHANGE A crack in the natural-gas bridge Integrated

  18. Modeling of crack initiation, propagation and coalescence in rocks

    E-Print Network [OSTI]

    Gonçalves da Silva, Bruno Miguel

    2009-01-01T23:59:59.000Z

    Natural or artificial fracturing of rock plays a very important role in geologic processes and for engineered structures in and on rock. Fracturing is associated with crack initiation, propagation and coalescence, which ...

  19. Crack coalescence in rock-like material under cycling loading

    E-Print Network [OSTI]

    Ko, Tae Young, 1973-

    2005-01-01T23:59:59.000Z

    A total of 170 tests (68 tests for monotonic loading, 102 tests for cyclic loading) have been performed to investigate crack initiation, propagation and coalescence. The specimens have two pre-existing flaws which are ...

  20. Field Examples of Axial Cracked Bearings in Wind Turbine Gearboxes...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Field Examples of Axial Cracked Bearings in Wind Turbine Gearboxes Presented by Paul John Baker of FrontierPro Services at the Wind Turbine Tribology Seminar 2014. 141030 Axial...

  1. Technique to eliminate helium induced weld cracking in stainless steels

    SciTech Connect (OSTI)

    Chin-An Wang; Chin, B.A. [Auburn Univ., AL (United States). Dept. of Materials Engineering; Grossbeck, M.L. [Oak Ridge National Lab., TN (United States)

    1992-12-31T23:59:59.000Z

    Experiments have shown that Type 316 stainless steel is susceptible to heat-affected-zone (HAZ) cracking upon cooling when welded using the gas tungsten arc (GTA) process under lateral constraint. The cracking has been hypothesized to be caused by stress-assisted helium bubble growth and rupture at grain boundaries. This study utilized an experimental welding setup which enabled different compressive stresses to be applied to the plates during welding. Autogenous GTA welds were produced in Type 316 stainless steel doped with 256 appm helium. The application of a compressive stress, 55 Mpa, during welding suppressed the previously observed catastrophic cracking. Detailed examinations conducted after welding showed a dramatic change in helium bubble morphology. Grain boundary bubble growth along directions parallel to the weld was suppressed. Results suggest that stress-modified welding techniques may be used to suppress or eliminate helium-induced cracking during joining of irradiated materials.

  2. Assessment of crack opening area for leak rates

    SciTech Connect (OSTI)

    Sharples, J.K.; Bouchard, P.J.

    1997-04-01T23:59:59.000Z

    This paper outlines the background to recommended crack opening area solutions given in a proposed revision to leak before break guidance for the R6 procedure. Comparisons with experimental and analytical results are given for some selected cases of circumferential cracks in cylinders. It is shown that elastic models can provide satisfactory estimations of crack opening displacement (and area) but they become increasingly conservative for values of L{sub r} greater than approximately 0.4. The Dugdale small scale yielding model gives conservative estimates of crack opening displacement with increasing enhancement for L{sub r} values greater than 0.4. Further validation of the elastic-plastic reference stress method for up to L{sub r} values of about 1.0 is presented by experimental and analytical comparisons. Although a more detailed method, its application gives a best estimate of crack opening displacement which may be substantially greater than small scale plasticity models. It is also shown that the local boundary conditions in pipework need to be carefully considered when evaluating crack opening area for through-wall bending stresses resulting from welding residual stresses or geometry discontinuities.

  3. Fluid delivery control system

    DOE Patents [OSTI]

    Hoff, Brian D.; Johnson, Kris William; Algrain, Marcelo C.; Akasam, Sivaprasad

    2006-06-06T23:59:59.000Z

    A method of controlling the delivery of fluid to an engine includes receiving a fuel flow rate signal. An electric pump is arranged to deliver fluid to the engine. The speed of the electric pump is controlled based on the fuel flow rate signal.

  4. Plasma-assisted catalytic storage reduction system

    DOE Patents [OSTI]

    Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA); Merritt, Bernard T. (Livermore, CA); Brusasco, Raymond M. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A two-stage method for NO.sub.x reduction in an oxygen-rich engine exhaust comprises a plasma oxidative stage and a storage reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. The second stage employs a lean NO.sub.x trap to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage with a plasma, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber in which a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, such as propene. A flow of such hydrocarbons (C.sub.x H.sub.y) is input from usually a second pipe into at least a portion of the first chamber. The NO.sub.2 from the plasma treatment proceeds to a storage reduction catalyst (lean NO.sub.x trap) that converts NO.sub.2 to N.sub.2, CO.sub.2, and H.sub.2 O, and includes a nitrate-forming catalytic site. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the lean-NO.sub.x trap catalyst. The method allows for enhanced NO.sub.x reduction in vehicular engine exhausts, particularly those having relatively high sulfur contents.

  5. Plasma-assisted catalytic storage reduction system

    DOE Patents [OSTI]

    Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA); Merritt, Bernard T. (Livermore, CA); Brusasco, Raymond M. (Livermore, CA)

    2000-01-01T23:59:59.000Z

    A two-stage method for NO.sub.x reduction in an oxygen-rich engine exhaust comprises a plasma oxidative stage and a storage reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. The second stage employs a lean NO.sub.x trap to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage with a plasma, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber in which a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, such as propene. A flow of such hydrocarbons (C.sub.x H.sub.y) is input from usually a second pipe into at least a portion of the first chamber. The NO.sub.2 from the plasma treatment proceeds to a storage reduction catalyst (lean NO.sub.x trap) that converts NO.sub.2 to N.sub.2, CO.sub.2, and H.sub.2 O, and includes a nitrate-forming catalytic site. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the lean-NO.sub.x trap catalyst. The method allows for enhanced NO.sub.x reduction in vehicular engine exhausts, particularly those having relatively high sulfur contents.

  6. Roles of grain boundaries in cleavage cracking and thermal crack arrest experiments in iron-silicon alloy

    E-Print Network [OSTI]

    Qiao, Yu, 1972-

    2002-01-01T23:59:59.000Z

    High-angle grain boundaries in steel offer an important resistance to the propagation of cleavage cracks that affects the fracture toughness and can modulate the ductile-to-brittle transition temperature of fracture downward. ...

  7. ffe1098 FFE March 7, 2007 21:55 Crack tip displacements of microstructurally small cracks in 316L steel

    E-Print Network [OSTI]

    Cizelj, Leon

    steel and their dependence on crystallographic orientations of grains I. SIMONOVSKI1 , KARL orientations on a short Stage I surface crack in a 316L stainless steel. The analysis is based on a plane

  8. Fluid blade disablement tool

    DOE Patents [OSTI]

    Jakaboski, Juan-Carlos (Albuquerque, NM); Hughs, Chance G. (Albuquerque, NM); Todd, Steven N. (Rio Rancho, NM)

    2012-01-10T23:59:59.000Z

    A fluid blade disablement (FBD) tool that forms both a focused fluid projectile that resembles a blade, which can provide precision penetration of a barrier wall, and a broad fluid projectile that functions substantially like a hammer, which can produce general disruption of structures behind the barrier wall. Embodiments of the FBD tool comprise a container capable of holding fluid, an explosive assembly which is positioned within the container and which comprises an explosive holder and explosive, and a means for detonating. The container has a concavity on the side adjacent to the exposed surface of the explosive. The position of the concavity relative to the explosive and its construction of materials with thicknesses that facilitate inversion and/or rupture of the concavity wall enable the formation of a sharp and coherent blade of fluid advancing ahead of the detonation gases.

  9. Strengthening, Crack Arrest And Multiple Cracking In Brittle Materials Using Residual Stresses.

    DOE Patents [OSTI]

    Green, David J. (State College, PA); Sglavo, Vincenzo M. (Roncegno, IT); Tandon, Rajan (Fremont, CA)

    2003-02-11T23:59:59.000Z

    Embodiments include a method for forming a glass which displays visible cracking prior to failure when subjected to predetermined stress level that is greater than a predetermined minimum stress level and less than a failure stress level. The method includes determining a critical flaw size in the glass and introducing a residual stress profile to the glass so that a plurality of visible cracks are formed prior to failure when the glass is subjected to a stress that is greater than the minimum stress level and lower than the critical stress. One method for forming the residual stress profile includes performing a first ion exchange so that a first plurality of ions of a first element in the glass are exchanged with a second plurality of ions of a second element that have a larger volume than the first ions. A second ion exchange is also performed so that a plurality of the second ions in the glass are exchanged back to ions of the first element.

  10. Ultra Low NOx Catalytic Combustion for IGCC Power Plants

    SciTech Connect (OSTI)

    Shahrokh Etemad; Benjamin Baird; Sandeep Alavandi; William Pfefferle

    2008-03-31T23:59:59.000Z

    In order to meet DOE's goals of developing low-emissions coal-based power systems, PCI has further developed and adapted it's Rich-Catalytic Lean-burn (RCL{reg_sign}) catalytic reactor to a combustion system operating on syngas as a fuel. The technology offers ultra-low emissions without the cost of exhaust after-treatment, with high efficiency (avoidance of after-treatment losses and reduced diluent requirements), and with catalytically stabilized combustion which extends the lower Btu limit for syngas operation. Tests were performed in PCI's sub-scale high-pressure (10 atm) test rig, using a two-stage (catalytic then gas-phase) combustion process for syngas fuel. In this process, the first stage consists of a fuel-rich mixture reacting on a catalyst with final and excess combustion air used to cool the catalyst. The second stage is a gas-phase combustor, where the air used for cooling the catalyst mixes with the catalytic reactor effluent to provide for final gas-phase burnout and dilution to fuel-lean combustion products. During testing, operating with a simulated Tampa Electric's Polk Power Station syngas, the NOx emissions program goal of less than 0.03 lbs/MMBtu (6 ppm at 15% O{sub 2}) was met. NOx emissions were generally near 0.01 lbs/MMBtu (2 ppm at 15% O{sub 2}) (PCI's target) over a range on engine firing temperatures. In addition, low emissions were shown for alternative fuels including high hydrogen content refinery fuel gas and low BTU content Blast Furnace Gas (BFG). For the refinery fuel gas increased resistance to combustor flashback was achieved through preferential consumption of hydrogen in the catalytic bed. In the case of BFG, stable combustion for fuels as low as 88 BTU/ft{sup 3} was established and maintained without the need for using co-firing. This was achieved based on the upstream catalytic reaction delivering a hotter (and thus more reactive) product to the flame zone. The PCI catalytic reactor was also shown to be active in ammonia reduction in fuel allowing potential reductions in the burner NOx production. These reductions of NOx emissions and expanded alternative fuel capability make the rich catalytic combustor uniquely situated to provide reductions in capital costs through elimination of requirements for SCR, operating costs through reduction in need for NOx abating dilution, SCR operating costs, and need for co-firing fuels allowing use of lower value but more available fuels, and efficiency of an engine through reduction in dilution flows.

  11. Correlations between surface structure and catalytic activity/selectivity

    SciTech Connect (OSTI)

    Goodman, D.W.

    1992-10-01T23:59:59.000Z

    Objective is to address the keys to understanding the relation between surface structure and catalytic activity/selectivity. Of concern are questions related to enhanced catalytic properties of mixed-metal catalysts and critical active site requirements for molecular synthesis and rearrangement. The experimental approach utilizes a microcatalytic reactor contiguous to a surface analysis system, an arrangement which allows in vacuo transfer of the catalyst from one chamber to the other. Surface techniques being used include Auger (AES), UV and X-ray photoemission spectroscopy (UPS and XPS), temperature programmed desorption (TPD), low energy electron diffraction (LEED), high resolution electron energy loss spectroscopy (HREELS) and infrared reflection-absorption spectroscopy (IRAS). Our research program builds upon our previous experience relating the results of single crystal kinetic measurements with the results obtained with supported analogs. As well we are exploiting our recent work on the preparation, the characterization, and the determination of the catalytic properties of ultra-thin metal and metal oxide films. The program is proceeding toward the study of the unique catalytic properties of ultrathin metal films; the investigation of the critical ensemble size requirements for principal catalytic reaction types; and the modelling of supported catalysts using ultra-thin planar oxide surfaces.

  12. FRACTURING FLUID CHARACTERIZATION FACILITY

    SciTech Connect (OSTI)

    Subhash Shah

    2000-08-01T23:59:59.000Z

    Hydraulic fracturing technology has been successfully applied for well stimulation of low and high permeability reservoirs for numerous years. Treatment optimization and improved economics have always been the key to the success and it is more so when the reservoirs under consideration are marginal. Fluids are widely used for the stimulation of wells. The Fracturing Fluid Characterization Facility (FFCF) has been established to provide the accurate prediction of the behavior of complex fracturing fluids under downhole conditions. The primary focus of the facility is to provide valuable insight into the various mechanisms that govern the flow of fracturing fluids and slurries through hydraulically created fractures. During the time between September 30, 1992, and March 31, 2000, the research efforts were devoted to the areas of fluid rheology, proppant transport, proppant flowback, dynamic fluid loss, perforation pressure losses, and frictional pressure losses. In this regard, a unique above-the-ground fracture simulator was designed and constructed at the FFCF, labeled ''The High Pressure Simulator'' (HPS). The FFCF is now available to industry for characterizing and understanding the behavior of complex fluid systems. To better reflect and encompass the broad spectrum of the petroleum industry, the FFCF now operates under a new name of ''The Well Construction Technology Center'' (WCTC). This report documents the summary of the activities performed during 1992-2000 at the FFCF.

  13. Multiphase fluid characterization system

    DOE Patents [OSTI]

    Sinha, Dipen N.

    2014-09-02T23:59:59.000Z

    A measurement system and method for permitting multiple independent measurements of several physical parameters of multiphase fluids flowing through pipes are described. Multiple acoustic transducers are placed in acoustic communication with or attached to the outside surface of a section of existing spool (metal pipe), typically less than 3 feet in length, for noninvasive measurements. Sound speed, sound attenuation, fluid density, fluid flow, container wall resonance characteristics, and Doppler measurements for gas volume fraction may be measured simultaneously by the system. Temperature measurements are made using a temperature sensor for oil-cut correction.

  14. Supercritical fluid extraction

    DOE Patents [OSTI]

    Wai, Chien M. (Moscow, ID); Laintz, Kenneth (Pullman, WA)

    1994-01-01T23:59:59.000Z

    A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated or lipophilic crown ether or fluorinated dithiocarbamate. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.

  15. Determination of crack morphology parameters from service failures for leak-rate analyses

    SciTech Connect (OSTI)

    Wilkowski, G.; Ghadiali, N.; Paul, D. [Battelle Memorial Institute, Columbus, OH (United States)] [and others

    1997-04-01T23:59:59.000Z

    In leak-rate analyses described in the literature, the crack morphology parameters are typically not well agreed upon by different investigators. This paper presents results on a review of crack morphology parameters determined from examination of service induced cracks. Service induced cracks were found to have a much more tortuous flow path than laboratory induced cracks due to crack branching associated with the service induced cracks. Several new parameters such as local and global surface roughnesses, as well as local and global number of turns were identified. The effect of each of these parameters are dependent on the crack-opening displacement. Additionally, the crack path is typically assumed to be straight through the pipe thickness, but the service data show that the flow path can be longer due to the crack following a fusion line, and/or the number of turns, where the number of turns in the past were included as a pressure drop term due to the turns, but not the longer flow path length. These parameters were statistically evaluated for fatigue cracks in air, corrosion-fatigue, IGSCC, and thermal fatigue cracks. A refined version of the SQUIRT leak-rate code was developed to account for these variables. Sample calculations are provided in this paper that show how the crack size can vary for a given leak rate and the statistical variation of the crack morphology parameters.

  16. Method for measuring recovery of catalytic elements from fuel cells

    DOE Patents [OSTI]

    Shore, Lawrence (Edison, NJ); Matlin, Ramail (Berkeley, NJ)

    2011-03-08T23:59:59.000Z

    A method is provided for measuring the concentration of a catalytic clement in a fuel cell powder. The method includes depositing on a porous substrate at least one layer of a powder mixture comprising the fuel cell powder and an internal standard material, ablating a sample of the powder mixture using a laser, and vaporizing the sample using an inductively coupled plasma. A normalized concentration of catalytic element in the sample is determined by quantifying the intensity of a first signal correlated to the amount of catalytic element in the sample, quantifying the intensity of a second signal correlated to the amount of internal standard material in the sample, and using a ratio of the first signal intensity to the second signal intensity to cancel out the effects of sample size.

  17. High-Resolution Characterizations of Stress-Corrosion Cracks in Austenitic Stainless Steel from Crack Growth Tests in BWR-Simulated Environments

    SciTech Connect (OSTI)

    Bruemmer, Stephen M.; Thomas, Larry E.

    2005-07-20T23:59:59.000Z

    Mechanisms controlling environmental degradation and cracking in light-water-reactor (LWR) systems have been investigated by analytical transmission electron microscopy (ATEM) of cracks and crack tips. The current work focuses on intergranular stress corrosion cracking (IGSCC) of 300-series, austenitic stainless steels in high-temperature LWR environments. Comparisons are made between cold-worked 304SS containing stress-corrosion cracks produced in a simulated boiling-water-reactor (BWR) environment during crack-growth tests, and a 304SS core component with cracks produced during 26-year BWR service. Similar corrosion products consisting of duplex-layered spinel oxides were found along the walls of open cracks in the service and laboratory test samples. These oxide films consisted of oriented Cr-rich spinel up to ~30 nm thick along the metal crack walls and large-grained Fe-rich spinel at the crack centers. Cracks in the service sample were generally more filled with oxide, perhaps reflecting the much longer times available for corrosion to occur after the crack passage. Crack tips in the BWR top-guide sample exhibited unique and unexpected structures with oxide-filled cracks <10 nm wide ending in finger-like attack and locally “dealloyed” zones of Fe/Cr-depleted, Ni-rich metal. Alloy compositions measured at numerous crack tips were 40 wt% Fe, 4 wt% Cr and 55 wt% Ni immediately ahead of the degradation front versus approximately 70 wt% Fe, 19 wt% Cr and 9 wt% Ni in the bulk 304SS. Laboratory samples with cracks grown over much shorted times (~1.5 months) did not show the distinctive crack tip structures or strong Ni enrichment in the metal ahead of the crack tips as for the service sample. This suggests that although selective oxidation processes occur during degradation, significant composition differences may only develop after crack propagation has slowed or stopped. Additional nanometer-scale measurements elucidating corrosion processes occurring during crack advance are presented to provide insights into mechanisms controlling IGSCC.

  18. Fuel Flexible, Low Emission Catalytic Combustor for Opportunity Fuel Applications

    SciTech Connect (OSTI)

    Eteman, Shahrokh

    2013-06-30T23:59:59.000Z

    Limited fuel resources, increasing energy demand and stringent emission regulations are drivers to evaluate process off-gases or process waste streams as fuels for power generation. Often these process waste streams have low energy content and/or highly reactive components. Operability of low energy content fuels in gas turbines leads to issues such as unstable and incomplete combustion. On the other hand, fuels containing higher-order hydrocarbons lead to flashback and auto-ignition issues. Due to above reasons, these fuels cannot be used directly without modifications or efficiency penalties in gas turbine engines. To enable the use of these wide variety of fuels in gas turbine engines a rich catalytic lean burn (RCL®) combustion system was developed and tested in a subscale high pressure (10 atm.) rig. The RCL® injector provided stability and extended turndown to low Btu fuels due to catalytic pre-reaction. Previous work has shown promise with fuels such as blast furnace gas (BFG) with LHV of 85 Btu/ft3 successfully combusted. This program extends on this work by further modifying the combustor to achieve greater catalytic stability enhancement. Fuels containing low energy content such as weak natural gas with a Lower Heating Value (LHV) of 6.5 MJ/m3 (180 Btu/ft3 to natural gas fuels containing higher hydrocarbon (e.g ethane) with LHV of 37.6 MJ/m3 (1010 Btu/ft3) were demonstrated with improved combustion stability; an extended turndown (defined as the difference between catalytic and non-catalytic lean blow out) of greater than 250oF was achieved with CO and NOx emissions lower than 5 ppm corrected to 15% O2. In addition, for highly reactive fuels the catalytic region preferentially pre-reacted the higher order hydrocarbons with no events of flashback or auto-ignition allowing a stable and safe operation with low NOx and CO emissions.

  19. Basic fluid system trainer

    DOE Patents [OSTI]

    Semans, Joseph P. (Uniontown, PA); Johnson, Peter G. (Pittsburgh, PA); LeBoeuf, Jr., Robert F. (Clairton, PA); Kromka, Joseph A. (Idaho Falls, ID); Goron, Ronald H. (Connellsville, PA); Hay, George D. (Venetia, PA)

    1993-01-01T23:59:59.000Z

    A trainer, mounted and housed within a mobile console, is used to teach and reinforce fluid principles to students. The system trainer has two centrifugal pumps, each driven by a corresponding two-speed electric motor. The motors are controlled by motor controllers for operating the pumps to circulate the fluid stored within a supply tank through a closed system. The pumps may be connected in series or in parallel. A number of valves are also included within the system to effect different flow paths for the fluid. In addition, temperature and pressure sensing instruments are installed throughout the closed system for measuring the characteristics of the fluid, as it passes through the different valves and pumps. These measurements are indicated on a front panel mounted to the console, as a teaching aid, to allow the students to observe the characteristics of the system.

  20. Basic fluid system trainer

    SciTech Connect (OSTI)

    Semans, J.P.; Johnson, P.G.; LeBoeuf, R.F. Jr.; Kromka, J.A.; Goron, R.H.; Hay, G.D.

    1991-04-30T23:59:59.000Z

    This invention, a trainer mounted and housed within a mobile console, is used to teach and reinforce fluid principles to students. The system trainer has two centrifugal pumps, each driven by a corresponding two-speed electric motor. The motors are controlled by motor controllers for operating the pumps to circulate the fluid stored within a supply tank through a closed system. The pumps may be connected in series or in parallel. A number of valves are also included within the system to effect different flow paths for the fluid. In addition, temperature and pressure sensing instruments are installed throughout the closed system for measuring the characteristics of the fluid, as it passes through the different valves and pumps. These measurements are indicated on a front panel mounted to the console, as a teaching aid, to allow the students to observe the characteristics of the system.

  1. Circulating Fluid Bed Combustor

    E-Print Network [OSTI]

    Fraley, L. D.; Do, L. N.; Hsiao, K. H.

    1982-01-01T23:59:59.000Z

    The circulating bed combustor represents an alternative concept of burning coal in fluid bed technology, which offers distinct advantages over both the current conventional fluidized bed combustion system and the pulverized coal boilers equipped...

  2. Phoresis in fluids

    E-Print Network [OSTI]

    Brenner, Howard

    This paper presents a unified theory of phoretic phenomena in single-component fluids. Simple formulas are given for the phoretic velocities of small inert force-free non-Brownian particles migrating through otherwise ...

  3. Fluid pumping apparatus

    DOE Patents [OSTI]

    West, Phillip B. (Idaho Falls, ID)

    2006-01-17T23:59:59.000Z

    A method and apparatus suitable for coupling seismic or other downhole sensors to a borehole wall in high temperature and pressure environments. In one embodiment, one or more metal bellows mounted to a sensor module are inflated to clamp the sensor module within the borehole and couple an associated seismic sensor to a borehole wall. Once the sensing operation is complete, the bellows are deflated and the sensor module is unclamped by deflation of the metal bellows. In a further embodiment, a magnetic drive pump in a pump module is used to supply fluid pressure for inflating the metal bellows using borehole fluid or fluid from a reservoir. The pump includes a magnetic drive motor configured with a rotor assembly to be exposed to borehole fluid pressure including a rotatable armature for driving an impeller and an associated coil under control of electronics isolated from borehole pressure.

  4. Progress in Statistical Crack Mechanics : An Approach to Initiation

    SciTech Connect (OSTI)

    Dienes, John K.; Middleditch, J. (John); Kershner, James D.; Zuo, Q. K. (Qiuhai K.); Starobin, A. J. (Andre J.)

    2002-01-01T23:59:59.000Z

    We have developed a general theory for the formation of hot spots from defects in explosives and propellants, and applied the theory to a variety of issues concerning the sensitivity of reactive materials. The defects of greatest concern in PBXs are cracks formed in the explosive grains, which are normally brittle. The theory accounts for the opening, shear, growth, and coalescence of cracks. In addition, the theory accounts for the heating caused by interfacial friction in closed (shear) cracks and the ignition process that results. Heat conduction and chemical reactions are treated on a smaller spatial scale than the overall continuum response; this is accomplished in the numerical (FEA) simulation with a sub-grid model. In previous work we have shown the feasibility of using this approach to model explosions that result from relatively mild insults, where many other hot-spot mechanisms fail. This paper addresses some of the complications that arise as mechanical failure and heating are examined in greater detail, including the effects of crack orientation, friction, melting, viscosity in molten regions, radial crack formation via a new approach to percolation theory, and 3-D effects.

  5. Develop statewide recommendations for application of PCC joint reflective cracking rehabilitation strategies

    E-Print Network [OSTI]

    Jain, Rahul Padamkumar

    2004-11-15T23:59:59.000Z

    Spalling of cracks and joints is the cracking, breaking or chipping of the slab edges within 2 ft (0.6m) if the joint or crack (Huang et. al 2004). Joint spalling is a construction related distress in the rigid pavement that mainly affects the structural... in the asphalt concrete overlays laid on the concrete pavements. Reflection cracks are caused by discontinuities in the underlying layers which propagate through the HMA surface due to movement at crack (Roberts et al 1996). Reflection cracks in AC overlays...

  6. Ultrarelativistic fluid dynamics

    E-Print Network [OSTI]

    David W. Neilsen; Matthew W. Choptuik

    1999-04-20T23:59:59.000Z

    This is the first of two papers examining the critical collapse of spherically symmetric perfect fluids with the equation of state P = (Gamma -1)rho. Here we present the equations of motion and describe a computer code capable of simulating the extremely relativistic flows encountered in critical solutions for Gamma <= 2. The fluid equations are solved using a high-resolution shock-capturing scheme based on a linearized Riemann solver.

  7. Valve for fluid control

    DOE Patents [OSTI]

    Oborny, Michael C. (Albuquerque, NM); Paul, Phillip H. (Livermore, CA); Hencken, Kenneth R. (Pleasanton, CA); Frye-Mason, Gregory C. (Cedar Crest, NM); Manginell, Ronald P. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A valve for controlling fluid flows. This valve, which includes both an actuation device and a valve body provides: the ability to incorporate both the actuation device and valve into a unitary structure that can be placed onto a microchip, the ability to generate higher actuation pressures and thus control higher fluid pressures than conventional microvalves, and a device that draws only microwatts of power. An electrokinetic pump that converts electric potential to hydraulic force is used to operate, or actuate, the valve.

  8. The backflow cell model for fluidized bed catalytic reactors

    E-Print Network [OSTI]

    Ganapathy, E. V

    1967-01-01T23:59:59.000Z

    THE BACKFLOW CELL MODEL FOR FLUIDI2ED BED CATALYTIC REACTORS A Thesis By E. V. Ganapathy Submitted to the Graduate College of the Texas A&M University in partial fulfillment of' the requirements for the degree of MASTER OF SCIENCE May 1967... Major Subject Chemical En ineerin THE BACKFLOW CELL MODEL FOR FLUIDIZED BED CATALYTIC REACTORS A Thesis E. V. Ganapathy Approved as to style and content by: chairman of Committee ~H+d d D p t t Member Member) May 1967 SO THE BACKFLOW CELL...

  9. CSE Master Specialization Fluid Dynamics

    E-Print Network [OSTI]

    Lang, Annika

    CSE Master Specialization Fluid Dynamics Course Semester Fluid Dynamics II HS Quantitative Flow Energie- und Verfahrenstechnik FS Biofluiddynamics FS #12;CSE in Fluid Dynamics: Very large high in Fluid Dynamics: Physiology of the inner ear MicroCT imaging Multilayer MFS for Stokes flow simulations

  10. Methods of using structures including catalytic materials disposed within porous zeolite materials to synthesize hydrocarbons

    DOE Patents [OSTI]

    Rollins, Harry W. (Idaho Falls, ID); Petkovic, Lucia M. (Idaho Falls, ID); Ginosar, Daniel M. (Idaho Falls, ID)

    2011-02-01T23:59:59.000Z

    Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.

  11. Continued investigations of the catalytic reduction of N? to NH? by molybdenum triamidoamine complexes

    E-Print Network [OSTI]

    Hanna, Brian S. (Brian Stewart)

    2011-01-01T23:59:59.000Z

    A study of the effects of employing different solvents and the introduction of dihydrogen during the catalytic reduction of dinitrogen to ammonia with [HIPTN 3N]Mo complexes was completed. During a catalytic reaction, the ...

  12. Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine

    E-Print Network [OSTI]

    Peck, Jhongwoo, 1976-

    2003-01-01T23:59:59.000Z

    As part of the MIT micro-gas turbine engine project, the development of a hydrocarbon-fueled catalytic micro-combustion system is presented. A conventionally-machined catalytic flow reactor was built to simulate the ...

  13. Impact of Biodiesel-Based Na on the Selective Catalytic Reduction...

    Broader source: Energy.gov (indexed) [DOE]

    Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NOx Using Cu-zeolite Impact of Biodiesel-Based Na on the Selective Catalytic Reduction (SCR) of NOx Using...

  14. Boundary integral formulation for interfacial cracks in thermodiffusive bimaterials

    E-Print Network [OSTI]

    L. Morini; A. Piccolroaz

    2015-04-29T23:59:59.000Z

    An original boundary integral formulation is proposed for the problem of a semi-infinite crack at the interface between two dissimilar elastic materials in the presence of heat flows and mass diffusion. Symmetric and skew-symmetric weight function matrices are used together with a generalized Betti's reciprocity theorem in order to derive a system of integral equations that relate the applied loading, the temperature and mass concentration fields, the heat and mass fluxes on the fracture surfaces and the resulting crack opening. The obtained integral identities can have many relevant applications, such as for the modelling of crack and damage processes at the interface between different components in electrochemical energy devices characterized by multi-layered structures (solid oxide fuel cells and lithium ions batteries).

  15. Method for fabrication of crack-free ceramic dielectric films

    DOE Patents [OSTI]

    Ma, Beihai; Balachandran, Uthamalingam; Chao, Sheng; Liu, Shanshan; Narayanan, Manoj

    2014-02-11T23:59:59.000Z

    The invention provides a process for forming crack-free dielectric films on a substrate. The process comprise the application of a dielectric precursor layer of a thickness from about 0.3 .mu.m to about 1.0 .mu.m to a substrate. The deposition is followed by low temperature heat pretreatment, prepyrolysis, pyrolysis and crystallization step for each layer. The deposition, heat pretreatment, prepyrolysis, pyrolysis and crystallization are repeated until the dielectric film forms an overall thickness of from about 1.5 .mu.m to about 20.0 .mu.m and providing a final crystallization treatment to form a thick dielectric film. Also provided was a thick crack-free dielectric film on a substrate, the dielectric forming a dense thick crack-free dielectric having an overall dielectric thickness of from about 1.5 .mu.m to about 20.0 .mu.m.

  16. Fluorescent fluid interface position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2004-02-17T23:59:59.000Z

    A new fluid interface position sensor has been developed, which is capable of optically determining the location of an interface between an upper fluid and a lower fluid, the upper fluid having a larger refractive index than a lower fluid. The sensor functions by measurement, of fluorescence excited by an optical pump beam which is confined within a fluorescent waveguide where that waveguide is in optical contact with the lower fluid, but escapes from the fluorescent waveguide where that waveguide is in optical contact with the upper fluid.

  17. Reflective Cracking Study: First-level Report on HVS Testing on Section 588RF - 90 mm AR4000-DOverlay

    E-Print Network [OSTI]

    Jones, David; Wu, R; Harvey, John T

    2008-01-01T23:59:59.000Z

    testing being performed to validate Caltrans overlay strategies for the rehabilitation of cracked asphalt concrete.concrete. It describes the results of the fourth HVS reflective cracking testingconcrete. It describes the results of the fourth HVS reflective cracking testing

  18. Reflective Cracking Study: First-Level Report on HVS Testing on Section 590RF - 90 mm MB4-G Overlay

    E-Print Network [OSTI]

    Jones, David; Tsai, Bor-Wen; Harvey, John T

    2008-01-01T23:59:59.000Z

    testing being performed to validate Caltrans overlay strategies for the rehabilitation of cracked asphalt concrete.concrete. It describes the results of the first HVS reflective cracking testingconcrete. It describes the results of the first HVS reflective cracking testing

  19. Weld solidification cracking in 304 to 204L stainless steel

    SciTech Connect (OSTI)

    Hochanadel, Patrick W [Los Alamos National Laboratory; Lienert, Thomas J [Los Alamos National Laboratory; Martinez, Jesse N [Los Alamos National Laboratory; Johnson, Matthew Q [Los Alamos National Laboratory

    2010-09-15T23:59:59.000Z

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found.This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GTAW showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

  20. Weld solidification cracking in 304 to 304L stainless steel

    SciTech Connect (OSTI)

    Hochanadel, Patrick W [Los Alamos National Laboratory; Lienert, Thomas J [Los Alamos National Laboratory; Martinez, Jesse N [Los Alamos National Laboratory; Martinez, Raymond J [Los Alamos National Laboratory; Johnson, Matthew Q [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found. This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GT A W showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

  1. Dynamic crack initiation toughness : experiments and peridynamic modeling.

    SciTech Connect (OSTI)

    Foster, John T.

    2009-10-01T23:59:59.000Z

    This is a dissertation on research conducted studying the dynamic crack initiation toughness of a 4340 steel. Researchers have been conducting experimental testing of dynamic crack initiation toughness, K{sub Ic}, for many years, using many experimental techniques with vastly different trends in the results when reporting K{sub Ic} as a function of loading rate. The dissertation describes a novel experimental technique for measuring K{sub Ic} in metals using the Kolsky bar. The method borrows from improvements made in recent years in traditional Kolsky bar testing by using pulse shaping techniques to ensure a constant loading rate applied to the sample before crack initiation. Dynamic crack initiation measurements were reported on a 4340 steel at two different loading rates. The steel was shown to exhibit a rate dependence, with the recorded values of K{sub Ic} being much higher at the higher loading rate. Using the knowledge of this rate dependence as a motivation in attempting to model the fracture events, a viscoplastic constitutive model was implemented into a peridynamic computational mechanics code. Peridynamics is a newly developed theory in solid mechanics that replaces the classical partial differential equations of motion with integral-differential equations which do not require the existence of spatial derivatives in the displacement field. This allows for the straightforward modeling of unguided crack initiation and growth. To date, peridynamic implementations have used severely restricted constitutive models. This research represents the first implementation of a complex material model and its validation. After showing results comparing deformations to experimental Taylor anvil impact for the viscoplastic material model, a novel failure criterion is introduced to model the dynamic crack initiation toughness experiments. The failure model is based on an energy criterion and uses the K{sub Ic} values recorded experimentally as an input. The failure model is then validated against one class of problems showing good agreement with experimental results.

  2. Analysis of weld solidification cracking in cast nickel aluminide alloys

    SciTech Connect (OSTI)

    Santella, M.L.; Feng, Z. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

    1995-09-01T23:59:59.000Z

    A study of the response of several nickel aluminide alloys to SigmaJig testing was done to examine their weld solidification cracking behavior and the effect of Zr concentration. The alloys were based on the Ni-8Al-7.7Cr-1.5Mo-0.003B wt% composition and contained Zr concentrations of 3, 4.5, and 6 wt%. Vacuum induction melted ingots with a diameter of 2.7 in and weight about 18 lb were made of each alloy, and were used to make 2 x 2 x 0.030 in specimens for the Sigmajig test. The gas tungsten arc welds were made at travel speeds of 10, 20, and 30 ipm with heat inputs of 2--2.5 kJ/in. When an arc was established before traveling onto the test specimen centerline cracking was always observed. This problem was overcome by initiating the arc directly on the specimens. Using this approach, the 3 wt% Zr alloy withstood an applied stress of 24 ksi without cracking at a welding speed of 10 ipm. This alloy cracked at 4 ksi applied at 20 ipm, and with no applied load at 30 ipm. Only limited testing was done on the remaining alloys, but the results indicate that resistance to solidification cracking increases with Zr concentration. Zirconium has limited solid solubility and segregates strongly to interdendritic regions during solidification where it forms a Ni solid solution-Ni{sub 5}Zr eutectic. The volume fraction of the eutectic increases with Zr concentration. The solidification cracking behavior of these alloys is consistent with phenomenological theory, and is discussed in this context. The results from SigmaJig testing are analyzed using finite element modeling of the development of mechanical strains during solidification of welds. Experimental data from the test substantially agree with recent analysis results.

  3. Stress Corrosion Crack Detection on HU-25 Guardian Aircraft

    SciTech Connect (OSTI)

    Blackmon, R.; Huffman, J.; Mello, C.W.; Moore, D.G.; Walkington, P.D.

    1999-02-17T23:59:59.000Z

    Several ultrasonic inspection methods were developed at the Federal Aviation Administration's Airworthiness Assurance NDI Validation Center (AANC) to easily and rapidly detect hidden stress corrosion cracks in all vertical windshield posts on the US Coast Guard (USCG) HU-25 Guardian aircraft. The inspection procedure locates cracks as small as 2.0 millimeters emanating from internal fastener holes and determines their length. A test procedure was developed and a baseline assessment of the USCG fleet was conducted. Inspection results on twenty-five aircraft revealed a good correlation with results made during subsequent structural disassembly and visual inspection.

  4. Interacting FisherWright Diffusions in a Catalytic Medium Andreas Greven

    E-Print Network [OSTI]

    Klenke, Achim

    environment (catalytic medium). Here we introduce a model of interacting Fisher­Wright diffusions where environment, catalytic medium, longtime behaviour, rescaling. AMS Subject Classification: 60K35, 60J70Interacting Fisher­Wright Diffusions in a Catalytic Medium Andreas Greven Mathematisches Institut

  5. Data reconciliation and optimal operation of a catalytic naphtha reformer

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Data reconciliation and optimal operation of a catalytic naphtha reformer Tore Lid Statoil Mongstad-mail:skoge@chemeng.ntnu.no) #12;Abstract The naphtha reforming process converts low-octane gasoline blending compo- nents to high-octane components for use in high-performance gasoline fuels. The reformer also has a important function

  6. Data reconciliation and optimal operation of a catalytic naphtha reformer

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Data reconciliation and optimal operation of a catalytic naphtha reformer Tore Lid Statoil Mongstad-mail:skoge@chemeng.ntnu.no) #12;Abstract The naphtha reforming process converts low-octane gasoline blending compo- nents to high-octane components for use in high-performance gasoline fuels. The reformer also has an important function

  7. Catalytic two-stage coal hydrogenation and hydroconversion process

    DOE Patents [OSTI]

    MacArthur, James B. (Denville, NJ); McLean, Joseph B. (So. Somerville, NJ); Comolli, Alfred G. (Yardley, PA)

    1989-01-01T23:59:59.000Z

    A process for two-stage catalytic hydrogenation and liquefaction of coal to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal is slurried with a process-derived liquid solvent and fed at temperature below about 650.degree. F. into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils at conditions favoring hydrogenation reactions. The first stage reactor is maintained at 650.degree.-800.degree. F. temperature, 1000-4000 psig hydrogen partial pressure, and 10-60 lb coal/hr/ft.sup.3 reactor space velocity. The partially hydrogenated material from the first stage reaction zone is passed directly to the close-coupled second stage catalytic reaction zone maintained at a temperature at least about 25.degree. F. higher than for the first stage reactor and within a range of 750.degree.-875.degree. F. temperature for further hydrogenation and thermal hydroconversion reactions. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, which results in significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of undesirable residuum and unconverted coal and hydrocarbon gases, with use of less energy to obtain the low molecular weight products, while catalyst life is substantially increased.

  8. Catalytic Methane Reduction in the Exhaust Gas of Combustion Engines

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    Catalytic Methane Reduction in the Exhaust Gas of Combustion Engines Peter Mauermann1,* , Michael Dornseiffer6 , Frank Amkreutz6 1 Institute for Combustion Engines , RWTH Aachen University, Schinkelstr. 8, D of the hydrocarbon exhaust of internal combustion engines. In contrast to other gaseous hydrocarbons, significant

  9. In-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect (OSTI)

    Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01T23:59:59.000Z

    This technology pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  10. Ex-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect (OSTI)

    Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01T23:59:59.000Z

    This technology pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  11. Catalytic, Enantioselective Alkylations of N,O-Acetals

    E-Print Network [OSTI]

    Lectka, Thomas

    , 10998-10999. (2) Hoveyda et al. have developed a Ni-catalyzed alkylation reaction of allylic acetalsCatalytic, Enantioselective Alkylations of N,O-Acetals Dana Ferraris, Travis Dudding, Brandon Young alkylation reactions of acetals have attained a prominent position in organic synthesis.1 Methods employing

  12. Catalytic Asymmetric Synthesis of Hydroxy Enol Ethers: Approach to a

    E-Print Network [OSTI]

    Walsh, Patrick J.

    for the generation of polypro- pionate backbone.1-7 In contrast, the asymmetric acetate aldol reaction that leads associated with acetate aldol reactions have prompted investigations into alternative methods to generate the catalytic asymmetric allylation of aldehydes followed by oxidative cleavage of the allyl group (Scheme 1, A

  13. Catalytic Domain of Phosphoinositide-specific Phospholipase C (PLC)

    E-Print Network [OSTI]

    Williams, Roger L.

    Catalytic Domain of Phosphoinositide-specific Phospholipase C (PLC) MUTATIONAL ANALYSIS OF RESIDUES WITHIN THE ACTIVE SITE AND HYDROPHOBIC RIDGE OF PLC 1* (Received for publication, November 20, 1997 Institute, University of Dundee, Dundee DD1 4HN, United Kingdom Structural studies of phospholipase C 1 (PLC

  14. Utilization of char from biomass gasification in catalytic applications

    E-Print Network [OSTI]

    temperature or time. In addition, micropores were observed in char that was made in CO2, but not in char, but sintering was not observed during gasification with CO2. This showed that the properties of char depend catalytically or thermally. However, thermal decomposition requires high temperatures, and catalyst deactivation

  15. Short Communication Catalytic coal gasification: use of calcium versus potassium*

    E-Print Network [OSTI]

    Short Communication Catalytic coal gasification: use of calcium versus potassium* Ljubisa R of calcium is related to its sintering via crystallite growth. (Keywords: coal; gasification; catalysis was to study the relative merits (or liabilities) of these two catalysts in coal char gasification. This work

  16. Structural Dynamics of a Catalytic Monolayer Probed by Ultrafast

    E-Print Network [OSTI]

    Fayer, Michael D.

    REPORTS Structural Dynamics of a Catalytic Monolayer Probed by Ultrafast 2D IR Vibrational Echoes in solutions. Here, we extend the technique to probing the interfacial dynamics and structure of a silica. The structural dynamics, as reported on by a carbonyl stretch vibration of the surface-bound complex, have

  17. Failure probability of axially cracked steam generator tubes; A probabilistic fracture mechanics model

    SciTech Connect (OSTI)

    Mavko, B.; Cizelj, L. (Jozef Stefan Inst., Reactor Engineering Div., P.O. Box 100, 61111 Ljubljana, Slovenia (YU))

    1992-05-01T23:59:59.000Z

    In this paper a model for estimating the failure probability of axially cracked steam generator tubes is proposed. The model compares observed crack length distribution with critical crack length distribution by means of probabilistic fracture mechanics. The observed crack length is influenced by measured data, measurement reliability, sizing accuracy, and predicted crack growth rate. The critical crack length is defined by a deterministic mechanical model. All cracks are conservatively assumed to extend through the tube wall. The effect of the plugging limit is studied along with the number of cracked tubes to perform risk-based lifetime optimization of steam generators. A numerical example presented considers hypothetical accidental operating conditions during a feedwater line break.

  18. Monitoring Cracking of a Smectitic Vertisol using Three-dimensional Electrical Resistivity Tomography

    E-Print Network [OSTI]

    Ackerson, Jason Paul

    2013-11-20T23:59:59.000Z

    Upon desiccation, the matrix of Vertisols and other expansive soils shrinks. Matrix shrinkage results in the formation of cracks that can alter the hydrology of the soil. Despite the importance of cracks, many hydrologic models do not account...

  19. Industrial Gas Turbine Engine Catalytic Pilot Combustor-Prototype Testing

    SciTech Connect (OSTI)

    Shahrokh Etemad; Benjamin Baird; Sandeep Alavandi; William Pfefferle

    2009-09-30T23:59:59.000Z

    PCI has developed and demonstrated its Rich Catalytic Lean-burn (RCL®) technology for industrial and utility gas turbines to meet DOEâ??s goals of low single digit emissions. The technology offers stable combustion with extended turndown allowing ultra-low emissions without the cost of exhaust after-treatment and further increasing overall efficiency (avoidance of after-treatment losses). The objective of the work was to develop and demonstrate emission benefits of the catalytic technology to meet strict emissions regulations. Two different applications of the RCL® concept were demonstrated: RCL® catalytic pilot and Full RCL®. The RCL® catalytic pilot was designed to replace the existing pilot (a typical source of high NOx production) in the existing Dry Low NOx (DLN) injector, providing benefit of catalytic combustion while minimizing engine modification. This report discusses the development and single injector and engine testing of a set of T70 injectors equipped with RCL® pilots for natural gas applications. The overall (catalytic pilot plus main injector) program NOx target of less than 5 ppm (corrected to 15% oxygen) was achieved in the T70 engine for the complete set of conditions with engine CO emissions less than 10 ppm. Combustor acoustics were low (at or below 0.1 psi RMS) during testing. The RCL® catalytic pilot supported engine startup and shutdown process without major modification of existing engine controls. During high pressure testing, the catalytic pilot showed no incidence of flashback or autoignition while operating over a wide range of flame temperatures. In applications where lower NOx production is required (i.e. less than 3 ppm), in parallel, a Full RCL® combustor was developed that replaces the existing DLN injector providing potential for maximum emissions reduction. This concept was tested at industrial gas turbine conditions in a Solar Turbines, Incorporated high-pressure (17 atm.) combustion rig and in a modified Solar Turbines, Incorporated Saturn engine rig. High pressure single-injector rig and modified engine rig tests demonstrated NOx less than 2 ppm and CO less than 10 ppm over a wide flame temperature operating regime with low combustion noise (<0.15% peak-to-peak). Minimum NOx for the optimized engine retrofit Full RCL® designs was less than 1 ppm with CO emissions less than 10 ppm. Durability testing of the substrate and catalyst material was successfully demonstrated at pressure and temperature showing long term stable performance of the catalytic reactor element. Stable performance of the reactor element was achieved when subjected to durability tests (>5000 hours) at simulated engine conditions (P=15 atm, Tin=400C/750F.). Cyclic tests simulating engine trips was also demonstrated for catalyst reliability. In addition to catalyst tests, substrate oxidation testing was also performed for downselected substrate candidates for over 25,000 hours. At the end of the program, an RCL® catalytic pilot system has been developed and demonstrated to produce NOx emissions of less than 3 ppm (corrected to 15% O2) for 100% and 50% load operation in a production engine operating on natural gas. In addition, a Full RCL® combustor has been designed and demonstrated less than 2 ppm NOx (with potential to achieve 1 ppm) in single injector and modified engine testing. The catalyst/substrate combination has been shown to be stable up to 5500 hrs in simulated engine conditions.

  20. Fluid driven reciprocating apparatus

    DOE Patents [OSTI]

    Whitehead, J.C.

    1997-04-01T23:59:59.000Z

    An apparatus is described comprising a pair of fluid driven pump assemblies in a back-to-back configuration to yield a bi-directional pump. Each of the pump assemblies includes a piston or diaphragm which divides a chamber therein to define a power section and a pumping section. An intake-exhaust valve is connected to each of the power sections of the pump chambers, and function to direct fluid, such as compressed air, into the power section and exhaust fluid therefrom. At least one of the pistons or diaphragms is connected by a rod assembly which is constructed to define a signal valve, whereby the intake-exhaust valve of one pump assembly is controlled by the position or location of the piston or diaphragm in the other pump assembly through the operation of the rod assembly signal valve. Each of the pumping sections of the pump assemblies are provided with intake and exhaust valves to enable filling of the pumping section with fluid and discharging fluid therefrom when a desired pressure has been reached. 13 figs.

  1. Fluid driven recipricating apparatus

    DOE Patents [OSTI]

    Whitehead, John C. (Davis, CA)

    1997-01-01T23:59:59.000Z

    An apparatus comprising a pair of fluid driven pump assemblies in a back-to-back configuration to yield a bi-directional pump. Each of the pump assemblies includes a piston or diaphragm which divides a chamber therein to define a power section and a pumping section. An intake-exhaust valve is connected to each of the power sections of the pump chambers, and function to direct fluid, such as compressed air, into the power section and exhaust fluid therefrom. At least one of the pistons or diaphragms is connected by a rod assembly which is constructed to define a signal valve, whereby the intake-exhaust valve of one pump assembly is controlled by the position or location of the piston or diaphragm in the other pump assembly through the operation of the rod assembly signal valve. Each of the pumping sections of the pump assemblies are provided with intake and exhaust valves to enable filling of the pumping section with fluid and discharging fluid therefrom when a desired pressure has been reached.

  2. Hazardous fluid leak detector

    DOE Patents [OSTI]

    Gray, Harold E. (Las Vegas, NV); McLaurin, Felder M. (Las Vegas, NV); Ortiz, Monico (Las Vegas, NV); Huth, William A. (Las Vegas, NV)

    1996-01-01T23:59:59.000Z

    A device or system for monitoring for the presence of leaks from a hazardous fluid is disclosed which uses two electrodes immersed in deionized water. A gas is passed through an enclosed space in which a hazardous fluid is contained. Any fumes, vapors, etc. escaping from the containment of the hazardous fluid in the enclosed space are entrained in the gas passing through the enclosed space and transported to a closed vessel containing deionized water and two electrodes partially immersed in the deionized water. The electrodes are connected in series with a power source and a signal, whereby when a sufficient number of ions enter the water from the gas being bubbled through it (indicative of a leak), the water will begin to conduct, thereby allowing current to flow through the water from one electrode to the other electrode to complete the circuit and activate the signal.

  3. SEPTARIAN CONCRETIONS Septarian structures are former cracks, often lled with cement

    E-Print Network [OSTI]

    S SEPTARIAN CONCRETIONS Septarian structures are former cracks, often ®lled with cement may show a component of shear displacement. Crack filling cements Cracks may range from largely un®lled to fully cement ®lled, often with a variety of distinctively colored spar cements. The ®lls may also

  4. A fast multipole boundary element method for modeling 2-D multiple crack problems with constant elements

    E-Print Network [OSTI]

    Liu, Yijun

    A fast multipole boundary element method for modeling 2-D multiple crack problems with constant 3 April 2014 Accepted 20 May 2014 Keywords: Fast multipole BEM 2-D multi-crack problems Constant elements Crack opening displacements Stress intensity factors a b s t r a c t A fast multipole boundary

  5. Hot cracking in tungsten inert gas welding of magnesium alloy AZ91D

    E-Print Network [OSTI]

    Zhou, Wei

    Hot cracking in tungsten inert gas welding of magnesium alloy AZ91D W. Zhou*, T. Z. Long and C. K of the plates were produced using tungsten inert gas (TIG) welding method. The TIG arc was also used to deposit welding beads on some of the thin plates. No cracking was found in the butt joints. However, hot cracking

  6. Stress corrosion cracking under low stress: Continuous or discontinuous Longkui K. Zhu a

    E-Print Network [OSTI]

    Volinsky, Alex A.

    Stress corrosion cracking under low stress: Continuous or discontinuous cracks? Longkui K. Zhu a , Yu Yan a , Jinxu X. Li a , Lijie J. Qiao a, , Alex A. Volinsky b,a a Corrosion and Protection Center. Stress corrosion C. Anodic dissolution a b s t r a c t Two-dimensional and three-dimensional crack

  7. Effects of Matrix Cracks on the Thermal Diffusivity of a Fiber-Reinforced Ceramic Composite

    E-Print Network [OSTI]

    Zok, Frank

    Effects of Matrix Cracks on the Thermal Diffusivity of a Fiber-Reinforced Ceramic Composite of Engineering Science, University of Western Ontario, London, Ontario N6A 5B9, Canada Effects of matrix cracks conductances coupled with a unit cell model for a fiber composite containing a periodic array of matrix cracks

  8. Thermal resistance of bridged cracks in fiber-reinforced ceramic John Dryden

    E-Print Network [OSTI]

    Zok, Frank

    -reinforced ceramic composites obtain high toughness is through the de- velopment of multiple matrix cracksThermal resistance of bridged cracks in fiber-reinforced ceramic composites John Dryden Department November 2000; accepted for publication 16 January 2001 The thermal resistance of a bridged matrix crack

  9. Analytical Investigation of Repair Methods for Fatigue Cracks in Steel Bridges

    E-Print Network [OSTI]

    Richardson, Temple

    2012-08-31T23:59:59.000Z

    ..................................................................................................................... 22 Retrofit measure 5: Bolted Stiffener-to-Flange Angles .......................................................................................... 23 Retrofit measure 6: Bolted Web-to-Stiffener Angles and Backing Plate... crack and a 204-mm (8-in.) web-to-flange weld crack. ............................................. 55 Table 2. Comparison of stress intensity factors for three crack surface displacements with the web-to-stiffener angles and a backing plate retrofit...

  10. A cracked beam finite element for rotating shaft dynamics and stability analysis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A cracked beam finite element for rotating shaft dynamics and stability analysis Saber El Arem Palaiseau, France Abstract In this paper, a method for the construction of a cracked beam finite element is presented. The additional flexibility due to the cracks is identified from three- dimensional finite element

  11. A creep model for austenitic stainless steels incorporating cavitation and wedge cracking

    E-Print Network [OSTI]

    Mahesh, Sivasambu

    A creep model for austenitic stainless steels incorporating cavitation and wedge cracking S Mahesh evolution in the form of cavitation and wedge- cracking on grain boundary facets is considered. Both: Austenitic stainless steel, creep, grain boundary sliding, cavitation, wedge- cracking. Submitted to

  12. Solvent control of crack dynamics in a reversible hydrogel

    E-Print Network [OSTI]

    Tristan Baumberger; Christiane Caroli; David Martina

    2006-05-16T23:59:59.000Z

    The resistance to fracture of reversible biopolymer hydrogels is an important control factor of the cutting/slicing and eating characteristics of food gels. It is also critical for their utilization in tissue engineering, for which mechanical protection of encapsulated components is needed. Its dependence on loading rate and, recently, on the density and strength of cross-links has been investigated. But no attention was paid so far to solvent nor to environment effects. Here we report a systematic study of crack dynamics in gels of gelatin in water/glycerol mixtures. We show on this model system that: (i) increasing solvent viscosity slows down cracks; (ii) soaking with solvent increases markedly gel fragility; (iii) tuning the viscosity of the (miscible) environmental liquid affects crack propagation via diffusive invasion of the crack tip vicinity. The results point toward the fact that fracture occurs by viscoplastic chain pull-out. This mechanism, as well as the related phenomenology, should be common to all reversibly cross-linked (physical) gels.

  13. Thin film with oriented cracks on a flexible substrate

    DOE Patents [OSTI]

    Feng, Bao; McGilvray, Andrew; Shi, Bo

    2010-07-27T23:59:59.000Z

    A thermoelectric film is disclosed. The thermoelectric film includes a substrate that is substantially electrically non-conductive and flexible and a thermoelectric material that is deposited on at least one surface of the substrate. The thermoelectric film also includes multiple cracks oriented in a predetermined direction.

  14. CONTAINED PLASTIC DEFORMATION NEAR CRACKS AND NOTCHES UNDER LONGITUDINAL SHEAR

    E-Print Network [OSTI]

    CONTAINED PLASTIC DEFORMATION NEAR CRACKS AND NOTCHES UNDER LONGITUDINAL SHEAR James R. Rice* ABSTRACT An exact linear elastic-perfectly plastic solution is presented for the problem of a sharp notch coordinates corresponding to given stresses, position of the elastic-plastic boundary, and accompanying

  15. Variable amplitude fatigue crack growth, experimental results and modeling

    E-Print Network [OSTI]

    a,*, F. Bumbieler b a Laboratory of Mechanics and Technology Cachan, 61, Avenue du Pre´s. Wilson method. This identification was performed for a 0.48%C carbon steel. Then various fatigue crack growth) is required so as to capture the very details of the elastic­plastic cyclic deformation of the mate- rial

  16. Fracture mechanics analysis of slow crack growth in polyethylene

    E-Print Network [OSTI]

    Self, Robert Alan

    1997-01-01T23:59:59.000Z

    polyethylenes were used to evaluate the new test and analysis methods. Static loading of deeply notched three-point bend specimens was conducted at 26.7 'C, 40 'C, and 70 'C on 1.27 cm , 0.953 cm, and 0.635 cm material. The crack length as a function of time...

  17. EARLY-AGE CRACKING REVIEW: MECHANISMS, MATERIAL PROPERTIES,

    E-Print Network [OSTI]

    Bentz, Dale P.

    ://cementbarriers.org/ and Savannah River National Laboratory website: http://srnl.doe.gov #12;Early-Age Cracking Review: Mechanisms Commission (NRC), the National Institute of Standards and Technology (NIST), the Savannah River National of work performed in part under that contract. This report was prepared in support of the Savannah River

  18. Crack-resistant siloxane molding compounds. [Patent application

    DOE Patents [OSTI]

    McFarland, J.W.; Swearngin, C.B.

    1980-11-03T23:59:59.000Z

    The crack resistance of phenyl silicone molding resins containing siliceous fillers is improved by incorporating therein about 0.5 to 5.5% by weight of ..beta..-eucryptite, a lithium aluminum silicate having a negative thermal expansion coefficient. These molding resins are particularly suitable for encapsulating electronic devices such as diodes, coils, resistors, and the like.

  19. AUTONOMOUS CRACK MEASUREMENT FOR COMPARISON OF VIBRATORY COMPACTION EXCITATION AND

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Establishment of the fragility of historic structures near rights of way often produces costly delays the potential for adjacent construction activities to cause cosmetic cracking in both historic and non-historic of Civil & Environmental Engineering, Northwestern University c-dowding@northwestern.edu ABSTRACT

  20. Method of making crack-free zirconium hydride

    DOE Patents [OSTI]

    Sullivan, Richard W. (Denver, CO)

    1980-01-01T23:59:59.000Z

    Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

  1. Steady crack growth in elasticplastic uid-saturated porous media

    E-Print Network [OSTI]

    Bigoni, Davide

    at the crack-tip were analyzed by van den Hoek et al. (1993) and Mohr-Coulomb elastoplasticity was considered a combined ®nite dierence/®nite element technique. In this article, an asymptotic solution is obtained criterion with volumetric non-associative ¯ow law and isotropic hardening. The technique used to solved

  2. Thin film cracking and ratcheting caused by temperature cycling

    E-Print Network [OSTI]

    Suo, Zhigang

    Thin film cracking and ratcheting caused by temperature cycling M. Huang and Z. Suo Mechanical caused by ratcheting in an adjacent ductile layer. For example, on a silicon die directly attached corners. Aided by cycling temperature, the shear stresses cause ratcheting in the aluminum pads

  3. Incipient Crack Detection in Composite Wind Turbine Blades

    SciTech Connect (OSTI)

    Taylor, Stuart G. [Los Alamos National Laboratory; Choi, Mijin [Chonbuk National University, Korea; Jeong, Hyomi [Chonbuk National University, Korea; Jang, Jae Kyeong [Chonbuk National University, Korea; Park, Gyuhae [Chonnam National University, Korea; Farinholt, Kevin [Commonwealth Center for Advanced Manufacturing, VA; Farrar, Charles R. [Los Alamos National Laboratory; Ammerman, Curtt N. [Los Alamos National Laboratory; Todd, Michael D. [Los Alamos National Laboratory; Lee, Jung-Ryul [Chonbuk National University, Korea

    2012-08-28T23:59:59.000Z

    This paper presents some analysis results for incipient crack detection in a 9-meter CX-100 wind turbine blade that underwent fatigue loading to failure. The blade was manufactured to standard specifications, and it underwent harmonic excitation at its first resonance using a hydraulically-actuated excitation system until reaching catastrophic failure. This work investigates the ability of an ultrasonic guided wave approach to detect incipient damage prior to the surfacing of a visible, catastrophic crack. The blade was instrumented with piezoelectric transducers, which were used in an active, pitchcatch mode with guided waves over a range of excitation frequencies. The performance results in detecting incipient crack formation in the fiberglass skin of the blade is assessed over the range of frequencies in order to determine the point at which the incipient crack became detectable. Higher excitation frequencies provide consistent results for paths along the rotor blade's carbon fiber spar cap, but performance falls off with increasing excitation frequencies for paths off of the spar cap. Lower excitation frequencies provide more consistent performance across all sensor paths.

  4. Method for recovering catalytic elements from fuel cell membrane electrode assemblies

    DOE Patents [OSTI]

    Shore, Lawrence (Edison, NJ); Matlin, Ramail (Berkeley Heights, NJ); Heinz, Robert (Ludwigshafen, DE)

    2012-06-26T23:59:59.000Z

    A method for recovering catalytic elements from a fuel cell membrane electrode assembly is provided. The method includes converting the membrane electrode assembly into a particulate material, wetting the particulate material, forming a slurry comprising the wetted particulate material and an acid leachate adapted to dissolve at least one of the catalytic elements into a soluble catalytic element salt, separating the slurry into a depleted particulate material and a supernatant containing the catalytic element salt, and washing the depleted particulate material to remove any catalytic element salt retained within pores in the depleted particulate material.

  5. TRACING FLUID SOURCES IN THE COSO GEOTHERMAL SYSTEM USING FLUID...

    Open Energy Info (EERE)

    FLUID-INCLUSION GAS CHEMISTRY Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: TRACING FLUID SOURCES IN THE COSO GEOTHERMAL SYSTEM USING...

  6. MEASUREMENT OF INTERFACIAL TENSION IN FLUID-FLUID SYSTEMS

    E-Print Network [OSTI]

    Loh, Watson

    MEASUREMENT OF INTERFACIAL TENSION IN FLUID-FLUID SYSTEMS J. Drelich Ch. Fang C.L. White Michigan been used to measure interfacial tensions between immisci- ble fluid phases. A recent monograph sources of information on the in- terfacial tension measurement methods include selected chapters in Refs

  7. FURTHER EXAMINATION OF CRACK TIP MICROSTRUCTURES IN F82H ON THE LOWER SHELF

    SciTech Connect (OSTI)

    Gelles, David S.; Odette, George R.; Spatig, P.

    2003-09-03T23:59:59.000Z

    Dislocation microstructures have been further examined near the crack tip of a compact tension specimen of unirradiated F82H loaded to 25.6 MPa m square root at –196 degrees C after fatigue precracking. A specimen was prepared by sectioning, dimple grinding and ion milling to produce electron transparency just ahead of the crack tip. Further ion milling has allowed improved examination of the microstructure immediately ahead of the crack tip. It is found that subgrain structure is relatively unaffected near the crack tip whereas 3 micron from the crack tip, dislocation loop structure was identified.

  8. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  9. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  10. Size Effect of Ruthenium Nanoparticles in Catalytic Carbon Monoxide Oxidation

    SciTech Connect (OSTI)

    Joo, Sang Hoon; Park, Jeong Y.; Renzas, J. Russell; Butcher, Derek R.; Huang, Wenyu; Somorjai, Gabor A.

    2010-04-04T23:59:59.000Z

    Carbon monoxide oxidation over ruthenium catalysts has shown an unusual catalytic behavior. Here we report a particle size effect on CO oxidation over Ru nanoparticle (NP) catalysts. Uniform Ru NPs with a tunable particle size from 2 to 6 nm were synthesized by a polyol reduction of Ru(acac){sub 3} precursor in the presence of poly(vinylpyrrolidone) stabilizer. The measurement of catalytic activity of CO oxidation over two-dimensional Ru NPs arrays under oxidizing reaction conditions (40 Torr CO and 100 Torr O{sub 2}) showed an activity dependence on the Ru NP size. The CO oxidation activity increases with NP size, and the 6 nm Ru NP catalyst shows 8-fold higher activity than the 2 nm catalysts. The results gained from this study will provide the scientific basis for future design of Ru-based oxidation catalysts.

  11. Catalytic destruction of groundwater contaminants in reactive extraction wells

    DOE Patents [OSTI]

    McNab, Jr., Walt W. (Concord, CA); Reinhard, Martin (Stanford, CA)

    2002-01-01T23:59:59.000Z

    A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

  12. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

    SciTech Connect (OSTI)

    Biddy, Mary J.; Jones, Susanne B.

    2013-03-31T23:59:59.000Z

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc.. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway to be competitive with petroleum-derived gasoline, diesel and jet range hydrocarbon blendstocks have been identified.

  13. Catalytic Combustion for Ultra-Low NOx Hydrogen Turbines

    SciTech Connect (OSTI)

    Etemad, Shahrokh; Baird, Benjamin; Alavandi, Sandeep

    2011-06-30T23:59:59.000Z

    Precision Combustion, Inc., (PCI) in close collaboration with Solar Turbines, Incorporated, has developed and demonstrated a combustion system for hydrogen fueled turbines that reduces NOx to low single digit level while maintaining or improving current levels of efficiency and eliminating emissions of carbon dioxide. Full scale Rich Catalytic Hydrogen (RCH1) injector was developed and successfully tested at Solar Turbines, Incorporated high pressure test facility demonstrating low single digit NOx emissions for hydrogen fuel in the range of 2200F-2750F. This development work was based on initial subscale development for faster turnaround and reduced cost. Subscale testing provided promising results for 42% and 52% H2 with NOx emissions of less than 2 ppm with improved flame stability. In addition, catalytic reactor element testing for substrate oxidation, thermal cyclic injector testing to simulate start-stop operation in a gas turbine environment, and steady state 15 atm. operation testing were performed successfully. The testing demonstrated stable and robust catalytic element component life for gas turbine conditions. The benefit of the catalytic hydrogen combustor technology includes capability of delivering near-zero NOx without costly post-combustion controls and without requirement for added sulfur control. In addition, reduced acoustics increase gas turbine component life. These advantages advances Department of Energy (DOE’s) objectives for achievement of low single digit NOx emissions, improvement in efficiency vs. postcombustion controls, fuel flexibility, a significant net reduction in Integrated Gasification Combined Cycle (IGCC) system net capital and operating costs, and a route to commercialization across the power generation field from micro turbines to industrial and utility turbines.

  14. Catalytic membrane reactors for chemicals upgrading and environmental control

    SciTech Connect (OSTI)

    Sammells, A.F. [Eltron Research, Inc., Boulder, CO (United States)

    1994-12-31T23:59:59.000Z

    Mixed ionic and electronic conducting catalytic membrane reactors are being developed for promoting a number of spontaneous chemical reactions either leading to synthesis of value added products or decomposition of environmental contaminants. The dense non-porous ceramic materials behave as short-circuited electrochemical devices whereby ions (oxygen anions or protons) and electrons become simultaneously mediated for one reaction surface to another. The rationale behind membrane materials selection and specific applications will be discussed.

  15. Hybrid lean premixing catalytic combustion system for gas turbines

    DOE Patents [OSTI]

    Critchley, Ian L.

    2003-12-09T23:59:59.000Z

    A system and method of combusting a hydrocarbon fuel is disclosed. The system combines the accuracy and controllability of an air staging system with the ultra-low emissions achieved by catalytic combustion systems without the need for a pre-heater. The result is a system and method that is mechanically simple and offers ultra-low emissions over a wide range of power levels, fuel properties and ambient operating conditions.

  16. Model catalytic oxidation studies using supported monometallic and heterobimetallic oxides

    SciTech Connect (OSTI)

    Ekerdt, J.G.

    1992-02-03T23:59:59.000Z

    This research program is directed toward a more fundamental understanding of the effects of catalyst composition and structure on the catalytic properties of metal oxides. Metal oxide catalysts play an important role in many reactions bearing on the chemical aspects of energy processes. Metal oxides are the catalysts for water-gas shift reactions, methanol and higher alcohol synthesis, isosynthesis, selective catalytic reduction of nitric oxides, and oxidation of hydrocarbons. A key limitation to developing insight into how oxides function in catalytic reactions is in not having precise information of the surface composition under reaction conditions. To address this problem we have prepared oxide systems that can be used to study cation-cation effects and the role of bridging (-O-) and/or terminal (=O) surface oxygen anion ligands in a systematic fashion. Since many oxide catalyst systems involve mixtures of oxides, we selected a model system that would permit us to examine the role of each cation separately and in pairwise combinations. Organometallic molybdenum and tungsten complexes were proposed for use, to prepare model systems consisting of isolated monomeric cations, isolated monometallic dimers and isolated bimetallic dimers supported on silica and alumina. The monometallic and bimetallic dimers were to be used as models of more complex mixed- oxide catalysts. Our current program was to develop the systems and use them in model oxidation reactions.

  17. Fatigue and Creep Crack Propagation behaviour of Alloy 617 in the Annealed and Aged Conditions

    SciTech Connect (OSTI)

    Julian K. Benz; Richard N. Wright

    2013-10-01T23:59:59.000Z

    The crack propagation behaviour of Alloy 617 was studied under various conditions. Elevated temperature fatigue and creep-fatigue crack growth experiments were conducted at 650 and 800 degrees C under constant stress intensity (triangle K) conditions and triangular or trapezoidal waveforms at various frequencies on as-received, aged, and carburized material. Environmental conditions included both laboratory air and characteristic VHTR impure helium. As-received Alloy 617 displayed an increase in the crack growth rate (da/dN) as the frequency was decreased in air which indicated a time-dependent contribution component in fatigue crack propagation. Material aged at 650°C did not display any influence on the fatigue crack growth rates nor the increasing trend of crack growth rate with decreasing frequency even though significant microstructural evolution, including y’ (Ni3Al) after short times, occurred during aging. In contrast, carburized Alloy 617 showed an increase in crack growth rates at all frequencies tested compared to the material in the standard annealed condition. Crack growth studies under quasi-constant K (i.e. creep) conditions were also completed at 650 degrees C and a stress intensity of K = 40 MPa9 (square root)m. The results indicate that crack growth is primarily intergranular and increased creep crack growth rates exist in the impure helium environment when compared to the results in laboratory air. Furthermore, the propagation rates (da/dt) continually increased for the duration of the creep crack growth either due to material aging or evolution of a crack tip creep zone. Finally, fatigue crack propagation tests at 800 degrees C on annealed Alloy 617 indicated that crack propagation rates were higher in air than impure helium at the largest frequencies and lowest stress intensities. The rates in helium, however, eventually surpass the rates in air as the frequency is reduced and the stress intensity is decreased which was not observed at 650 degrees C.

  18. Initiation of environmentally-assisted cracking in low-alloy steels

    SciTech Connect (OSTI)

    Wire, G.L.; Li, Y.Y.

    1996-06-01T23:59:59.000Z

    Environmentally-Assisted Cracking (EAC) in low alloy steels is activated by a critical level of sulfide ions at the crack tip, which is produced from dissolution of sulfide inclusions (MnS, FeS, etc.) in the steel following exposure by a growing crack. EAC of concern herein is the increase of fatigue crack growth rate of up to 40 to 100 times the rate in air that occurs at 240--300 C in high temperature LWR or boiler water environments. The initiation of EAC is the onset of the higher fatigue crack growth rates in fully developed cracks already presumed to be present due to fatigue, stress corrosion cracking, or induced by fabrication. Initiation of EAC is induced by a change in loading parameters causing the fatigue crack growth rate to increase from a small multiple (2--4) to 40--100 times the air rate. A steady state theory developed by Combrade, suggests that EAC will initiate only above a critical crack velocity and cease below this same velocity. However, more recent tests show that EAC can persist down to much lower velocities (100 times lower) in low oxygen water at slightly lower temperatures. A special set of experiments on high sulfur plate material demonstrate that EAC will not initiate from surface cracks with low sulfide inventories at low crack tip velocities. Transient diffusion calculations show that a finite crack extension at a high crack tip velocity is necessary to initiate EAC, providing a possible explanation for the lack of high crack growth observations reported in low alloy steels in structural applications involving low oxygen environments.

  19. Oscillating fluid power generator

    DOE Patents [OSTI]

    Morris, David C

    2014-02-25T23:59:59.000Z

    A system and method for harvesting the kinetic energy of a fluid flow for power generation with a vertically oriented, aerodynamic wing structure comprising one or more airfoil elements pivotably attached to a mast. When activated by the moving fluid stream, the wing structure oscillates back and forth, generating lift first in one direction then in the opposite direction. This oscillating movement is converted to unidirectional rotational movement in order to provide motive power to an electricity generator. Unlike other oscillating devices, this device is designed to harvest the maximum aerodynamic lift forces available for a given oscillation cycle. Because the system is not subjected to the same intense forces and stresses as turbine systems, it can be constructed less expensively, reducing the cost of electricity generation. The system can be grouped in more compact clusters, be less evident in the landscape, and present reduced risk to avian species.

  20. Fluid bed material transfer method

    DOE Patents [OSTI]

    Pinske, Jr., Edward E. (Akron, OH)

    1994-01-01T23:59:59.000Z

    A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

  1. Viscous dark fluid

    E-Print Network [OSTI]

    V. Folomeev; V. Gurovich

    2007-10-15T23:59:59.000Z

    The unified dark energy and dark matter model within the framework of a model of a continuous medium with bulk viscosity (dark fluid) is considered. It is supposed that the bulk viscosity coefficient is an arbitrary function of the Hubble parameter. The choice of this function is carried out under the requirement to satisfy the observational data from recombination ($z\\approx 1000$) till present time.

  2. Thermal cracking of rubber modified pavements, May 1995. Final report

    SciTech Connect (OSTI)

    Raad, L.; Yuan, X.; Saboundjian, S.

    1995-05-01T23:59:59.000Z

    In accordance with the original ISTEA mandate (1991) to use crumb tire rubber in pavements, Alaska would be required to use about 250 tons of used tire rubber starting in 1994 and increasing to about 1,000 tons of rubber in 1997 and each year thereafter. A number of pavements using crumb rubber modifiers have been built in the state and have been in service for periods of 8 to 15 years. Knowledge of the behavior of these rubber-modified pavements under extreme climate conditions, particularly in relation to their low temperature cracking resistance, is necessary for future design and construction of rubberized pavements in Alaska. This report presents results of a study to determine the low temperature cracking resistance of rubber modified pavements in Alaska in comparison with conventional asphalt concrete pavements.

  3. Downhole Fluid Analyzer Development

    SciTech Connect (OSTI)

    Bill Turner

    2006-11-28T23:59:59.000Z

    A novel fiber optic downhole fluid analyzer has been developed for operation in production wells. This device will allow real-time determination of the oil, gas and water fractions of fluids from different zones in a multizone or multilateral completion environment. The device uses near infrared spectroscopy and induced fluorescence measurement to unambiguously determine the oil, water and gas concentrations at all but the highest water cuts. The only downhole components of the system are the fiber optic cable and windows. All of the active components--light sources, sensors, detection electronics and software--will be located at the surface, and will be able to operate multiple downhole probes. Laboratory testing has demonstrated that the sensor can accurately determine oil, water and gas fractions with a less than 5 percent standard error. Once installed in an intelligent completion, this sensor will give the operating company timely information about the fluids arising from various zones or multilaterals in a complex completion pattern, allowing informed decisions to be made on controlling production. The research and development tasks are discussed along with a market analysis.

  4. Method for making dense crack free thin films

    DOE Patents [OSTI]

    Jacobson, Craig P. (Lafayette, CA); Visco, Steven J. (Berkeley, CA); De Jonghe, Lutgard C. (Lafayette, CA)

    2007-01-16T23:59:59.000Z

    The process described herein provides a simple and cost effective method for making crack free, high density thin ceramic film. The steps involve depositing a layer of a ceramic material on a porous or dense substrate. The deposited layer is compacted and then the resultant laminate is sintered to achieve a higher density than would have been possible without the pre-firing compaction step.

  5. Crack stability analysis of low alloy steel primary coolant pipe

    SciTech Connect (OSTI)

    Tanaka, T.; Kameyama, M. [Kansai Electric Power Company, Osaka (Japan); Urabe, Y. [Mitsubishi Heavy Industries, Ltd., Takasago (Japan)] [and others

    1997-04-01T23:59:59.000Z

    At present, cast duplex stainless steel has been used for the primary coolant piping of PWRs in Japan and joints of dissimilar material have been applied for welding to reactor vessels and steam generators. For the primary coolant piping of the next APWR plants, application of low alloy steel that results in designing main loops with the same material is being studied. It means that there is no need to weld low alloy steel with stainless steel and that makes it possible to reduce the welding length. Attenuation of Ultra Sonic Wave Intensity is lower for low alloy steel than for stainless steel and they have advantageous inspection characteristics. In addition to that, the thermal expansion rate is smaller for low alloy steel than for stainless steel. In consideration of the above features of low alloy steel, the overall reliability of primary coolant piping is expected to be improved. Therefore, for the evaluation of crack stability of low alloy steel piping to be applied for primary loops, elastic-plastic future mechanics analysis was performed by means of a three-dimensioned FEM. The evaluation results for the low alloy steel pipings show that cracks will not grow into unstable fractures under maximum design load conditions, even when such a circumferential crack is assumed to be 6 times the size of the wall thickness.

  6. Microstructural and solidification cracking evaluation of electron beam welds in 304L

    SciTech Connect (OSTI)

    Sturgill, P.L.; Campbell, R.D.; Henningsen, J.L.

    1991-01-01T23:59:59.000Z

    Weld hot cracking of stainless steels is a major materials-related problem in the welding industry. This present investigation evaluates the crack susceptibility of highly-constrained EB welds made in materials whose DeLong ferrite potentials range from zero to nine FN. In addition, the effect of piece part strength level on cracking is examined. This study has revealed that these deep penetration EB welds have regions that solidify as primary austenite, even when the DeLong ferrite potential is as high as 9 FN. This points out the critical role that solidification rate plays in the crack susceptibility of these highly restrained welds. In addition, 0 FN to 0 FN welds had primarily transverse cracks while 6 FN to 0 FN welds had primarily centerline cracks. Of particular interest is the observation that cracks still occur if a high ferrite (greater than 6 FN) component is welded to a zero FN component. Cracking is always associated with regions which solidify as primary austenite and these cracks occur because there are areas in the weld which do not mix. Thus it is not a recommended production practice to compensate for low ferrite in one piece part with high ferrite in its mate. Finally, it is shown that a DeLong FN threshold of 4 to prevent cracking in EB welds in not valid. 21 refs., 16 figs.

  7. Fatigue Crack Propagation from Notched Specimens of 304 SS in elevated Temperature Aqueous Environment

    SciTech Connect (OSTI)

    Wire, G. L.; Mills, W. J.

    2002-08-01T23:59:59.000Z

    Fatigue crack propagation (FCP) rates for 304 stainless steel (304SS) were determined in 24 degree C and 288 degree C air and 288 degree C water using double-edged notch (DEN) specimens of 304 stainless steel (304 SS). Test performed at matched loading conditions in air and water at 288 degree C with 20-6- cc h[sub]2/kg h[sub]2O provided a direct comparison of the relative crack growth rates in air and water over a wide range of crack growth rates. The DEN crack extension ranged from short cracks (0.03-0.25 mm) to long cracks up to 4.06 mm, which are consistent with conventional deep crack tests. Crack growth rates of 304 SS in water were about 12 times the air rate. This 12X environmental enhancement persisted to crack extensions up to 4.06 mm, far outside the range associated with short crack effects. The large environmental degradation for 304 SS crack growth is consistent with the strong reduction of fatigue life in high hydrogen water. Further, very similar environmental effects w ere reported in fatigue crack growth tests in hydrogen water chemistry (HWC). Most literature data in high hydrogen water show only a mild environmental effect for 304 SS, of order 2.5 times air or less, but the tests were predominantly performed at high cyclic stress intensity or equivalently, high air rates. The environmental effect in low oxygen environments at low stress intensity depends strongly on both the stress ratio, R, and the load rise time, T[sub]r, as recently reported for austenitic stainless steel in BWR water. Fractography was performed for both tests in air and water. At 288 degree C in water, the fracture surfaces were crisply faceted with a crystallographic appearance, and showed striations under high magnification. The cleavage-like facets on the fracture surfaces suggest that hydrogen embrittlement is the primary cause of accelerated cracking.

  8. Method and apparatus for monitoring a hydrocarbon-selective catalytic reduction device

    DOE Patents [OSTI]

    Schmieg, Steven J; Viola, Michael B; Cheng, Shi-Wai S; Mulawa, Patricia A; Hilden, David L; Sloane, Thompson M; Lee, Jong H

    2014-05-06T23:59:59.000Z

    A method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry includes injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device at a predetermined mass flowrate of the reductant, and determining a space velocity associated with a predetermined forward portion of the hydrocarbon-selective catalytic reactor device. When the space velocity exceeds a predetermined threshold space velocity, a temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is determined, and a threshold temperature as a function of the space velocity and the mass flowrate of the reductant is determined. If the temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is below the threshold temperature, operation of the engine is controlled to regenerate the hydrocarbon-selective catalytic reactor device.

  9. To Crack or Not to Crack: Strain in High TemperatureSuperconductors

    SciTech Connect (OSTI)

    Godeke, Arno

    2007-08-22T23:59:59.000Z

    Round wire Bi 2212 is emerging as a viable successor ofNb3Sn in High Energy Physics and Nuclear Magnetic Resonance, to generatemagnetic fields that surpass the intrinsic limitations of Nb3Sn. Ratherbold claims are made on achievable magnetic fields in applications usingBi 2212, due to the materials' estimated critical magnetic field of 100 Tor higher. High transport currents in high magnetic fields, however, leadto large stress on, and resulting large strain in the superconductor. Theeffect of strain on the critical properties of Bi-2212 is far fromunderstood, and strain is, as with Nb3Sn, often treated as a secondaryparameter in the design of superconducting magnets. Reversibility of thestrain induced change of the critical surface of Nb3Sn, points to anelectronic origin of the observed strain dependence. Record breaking highfield magnets are enabled by virtue of such reversible behavior. Straineffects on the critical surface of Bi-2212, in contrast, are mainlyirreversible and suggest a non-electronic origin of the observed straindependence, which appears to be dominated by the formation of cracks inthe superconductor volumes. A review is presented of available results onthe effects of strain on the critical surface of Bi-2212, Bi-2223 andYBCO. It is shown how a generic behavior emerges for the (axial) straindependence of the critical current density, and how the irreversiblereduction of the critical current density is dominated by strain inducedcrack formation in the superconductor. From this generic model it becomesclear that magnets using high temperature superconductors will be strainlimited far before the intrinsic magnetic field limitations will beapproached, or possibly even before the magnetic field limitation ofNb3Sn can be surpassed. On a positive note, in a very promising recentresult from NIST on the axial strain dependence of the critical currentdensity in extremely well aligned YBCO, reversible behavior was observed.This result emphasizes the need for further conductor development,specifically for round wire Bi-2212, to generate a wire with a similarreversible dependence on strain. Availability of such a wire will enablethe construction of magnets that can indeed generate fields that farsurpass the limitations of Nb3Sn superconductors.

  10. Petroleum Refinery Catalytic Reforming -- Cutting High Energy Costs 

    E-Print Network [OSTI]

    Viar, W. L.

    1979-01-01T23:59:59.000Z

    at temperatures of 850-950oF. Hydrogen - rich off - gases are fired in combinations of process furnaces. Heat is transferred to hydrocarbon fluids by radiation, principally. Feed or return stream temperatures determine the need for convection sections...

  11. Scaling Issues of Micro Catalytic Reactors Tzong-Shyng Leu1,a

    E-Print Network [OSTI]

    Leu, Tzong-Shyng "Jeremy"

    combustor, Microscale combustion, Power MEMS Abstract. Micro catalytic combustors are studied experimentally thermal management. For example, "Swiss Roll" [4] and multi-quartz tubes[5] utilized insulated conditions

  12. A Simple Approach of Tuning Catalytic Activity of MFI-Zeolites...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    & Publications Catalysts via First Principles (Agreement ID:10635) Catalysts via First Principles Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons...

  13. Solid state oxygen anion and electron mediating membrane and catalytic membrane reactors containing them

    SciTech Connect (OSTI)

    Schwartz, Michael (Boulder, CO); White, James H. (Boulder, CO); Sammells, Anthony F. (Boulder, CO)

    2001-01-01T23:59:59.000Z

    A process for production of synthesis gas employing a catalytic membrane reactor wherein the membrane comprises a mixed metal oxide material.

  14. New sub-family of lysozyme-like proteins shows no catalytic activity...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    modest sequence similarity to phage-like lysozyme (N-acetylmuramidase) but appears to lack essential catalytic residues that are strictly conserved in all lysozymes. Close...

  15. LUBRICANTS AND HYDRAULIC FLUIDS

    E-Print Network [OSTI]

    Engineer Manual Department

    Contents) Major General, USA Chief of Staff i Table of Contents Purpose ........................................................ 1-1 1-1 Applicability .................................................... 1-2 1-1 References ...................................................... 1-3 1-1 Distribution Statement ............................................. 1-4 1-1 Scope ......................................................... 1-5 1-2 Friction ........................................................ 2-1 2-1 Wear .......................................................... 2-2 2-4 Lubrication and Lubricants ......................................... 2-3 2-6 Hydrodynamic or Fluid Film Lubrication ............................... 2-4 2-6 Boundary Lubrication ............................................. 2-5 2-8 Extreme Pressure (EP) Lubrication ................................... 2-6 2-9 Elastohydrodynamic (EHD) Lubrication ................................ 2-7 2-9 Oil R

  16. Subcritical Crack Growth in Ceramic Composites at High Temperature Measured Using Digital Image Correlation

    SciTech Connect (OSTI)

    Mumm, D.R.; Morris, W.L.; Dadkhah, M.S.; Cox, B.N.

    1996-01-11T23:59:59.000Z

    An in situ experimental technique is described that allows high resolution, high sensitivity determination of displacements and full-field strains during high temperature mechanical testing. The technique is used to investigate elevated temperature crack growth in SiC/Nicalon sub f composites. At 1150 degrees C, the reinforcing fibers have a higher creep susceptibility than the matrix. Fiber creep leads to relaxation of crack bridging tractions, resulting in subcritical crack growth. Differential image analysis is used to measure the crack opening displacement profile u(x) of an advancing, bridged crack. With appropriate modeling, such data can be used to determine the traction law, from which the mechanics of cracking and failure may be determined.

  17. Method and apparatus for decoupled thermo-catalytic pollution control

    DOE Patents [OSTI]

    Tabatabaie-Raissi, Ali; Muradov, Nazim Z.; Martin, Eric

    2006-07-11T23:59:59.000Z

    A new method for design and scale-up of thermocatalytic processes is disclosed. The method is based on optimizing process energetics by decoupling of the process energetics from the DRE for target contaminants. The technique is applicable to high temperature thermocatalytic reactor design and scale-up. The method is based on the implementation of polymeric and other low-pressure drop support for thermocatalytic media as well as the multifunctional catalytic media in conjunction with a novel rotating fluidized particle bed reactor.

  18. Recent Advances in Catalytic Conversion of Ethanol to Chemicals

    SciTech Connect (OSTI)

    Sun, Junming; Wang, Yong

    2014-04-30T23:59:59.000Z

    With increased availability and decreased cost, ethanol is potentially a promising platform molecule for the production of a variety of value-added chemicals. In this review, we provide a detailed summary of recent advances in catalytic conversion of ethanol to a wide range of chemicals and fuels. We particularly focus on catalyst advances and fundamental understanding of reaction mechanisms involved in ethanol steam reforming (ESR) to produce hydrogen, ethanol conversion to hydrocarbons ranging from light olefins to longer chain alkenes/alkanes and aromatics, and ethanol conversion to other oxygenates including 1-butanol, acetaldehyde, acetone, diethyl ether, and ethyl acetate.

  19. Method for low temperature catalytic production of hydrogen

    DOE Patents [OSTI]

    Mahajan, Devinder

    2003-07-22T23:59:59.000Z

    The invention provides a process for the catalytic production of a hydrogen feed by exposing a hydrogen feed to a catalyst which promotes a base-catalyzed water-gas-shift reaction in a liquid phase. The hydrogen feed can be provided by any process known in the art of making hydrogen gas. It is preferably provided by a process that can produce a hydrogen feed for use in proton exchange membrane fuel cells. The step of exposing the hydrogen feed takes place preferably from about 80.degree. C. to about 150.degree. C.

  20. Catalytic Filter for Diesel Exhaust Purification | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof Energy Change RequestFirstchampions,Department ofConversionCatalytic

  1. New Developments in Titania-Based Catalysts for Selective Catalytic

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForum |EnergyNew CatalyticDemands on Heavy

  2. Assessments of fluid friction factors for use in leak rate calculations

    SciTech Connect (OSTI)

    Chivers, T.C. [Berkeley Technology Centre, Glos (United Kingdom)

    1997-04-01T23:59:59.000Z

    Leak before Break procedures require estimates of leakage, and these in turn need fluid friction to be assessed. In this paper available data on flow rates through idealized and real crack geometries are reviewed in terms of a single friction factor k It is shown that for {lambda} < 1 flow rates can be bounded using correlations in terms of surface R{sub a} values. For {lambda} > 1 the database is less precise, but {lambda} {approx} 4 is an upper bound, hence in this region flow calculations can be assessed using 1 < {lambda} < 4.

  3. Identifying and Understanding Environment-Induced Crack propagation Behavior in Ni-based Superalloy INCONEL 617

    SciTech Connect (OSTI)

    Ma, Longzhou

    2012-11-30T23:59:59.000Z

    The nickel-based superalloy INCONEL 617 is a candidate material for heat exchanger applications in the next-generation nuclear plant (NGNP) system. This project will study the crack propagation process of alloy 617 at temperatures of 650°C-950°C in air under static/cyclic loading conditions. The goal is to identify the environmental and mechanical damage components and to understand in-depth the failure mechanism. Researchers will measure the fatigue crack propagation (FCP) rate (da/dn) under cyclic and hold-time fatigue conditions, and sustained crack growth rates (da/dt) at elevated temperatures. The independent FCP process will be identified and the rate-controlled sustained loading crack process will be correlated with the thermal activation equation to estimate the oxygen thermal activation energy. The FCP-dependent model indicates that if the sustained loading crack growth rate, da/dt, can be correlated with the FCP rate, da/dn, at the full time dependent stage, researchers can confirm stress-accelerated grain-boundary oxygen embrittlement (SAGBOE) as a predominate effect. Following the crack propagation tests, the research team will examine the fracture surface of materials in various cracking stages using a scanning electron microscope (SEM) and an optical microscope. In particular, the microstructure of the crack tip region will be analyzed in depth using high resolution transmission electron microscopy (TEM) and electron energy loss spectrum (EELS) mapping techniques to identify oxygen penetration along the grain boundary and to examine the diffused oxygen distribution profile around the crack tip. The cracked sample will be prepared by focused ion beam nanofabrication technology, allowing researchers to accurately fabricate the TEM samples from the crack tip while minimizing artifacts. Researchers will use these microscopic and spectroscopic results to interpret the crack propagation process, as well as distinguish and understand the environment or SAGBOE damage process under hold-time fatigue and sustained loading conditions

  4. Ultrasonic Fluid Quality Sensor System

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2003-10-21T23:59:59.000Z

    A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.

  5. Ultrasonic fluid quality sensor system

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2002-10-08T23:59:59.000Z

    A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.

  6. Simulation of the ultrasonic array response from real branched cracks using an efficient finite element method

    SciTech Connect (OSTI)

    Felice, Maria V. [Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR, United Kingdom and Rolls-Royce plc., Bristol BS34 7QE (United Kingdom); Velichko, Alexander; Wilcox, Paul D. [Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR (United Kingdom); Barden, Tim J.; Dunhill, Tony K. [Rolls-Royce plc., Bristol BS34 7QE (United Kingdom)

    2014-02-18T23:59:59.000Z

    A hybrid model to simulate the ultrasonic array response from stress corrosion cracks is presented. These cracks are branched and difficult to detect so the model is required to enable optimization of an array design. An efficient frequency-domain finite element method is described and selected to simulate the ultrasonic scattering. Experimental validation results are presented, followed by an example of the simulated ultrasonic array response from a real stress corrosion crack whose geometry is obtained from an X-ray Computed Tomography image. A simulation-assisted array design methodology, which includes the model and use of real crack geometries, is proposed.

  7. Assessment and prediction of drying shrinkage cracking in bonded mortar overlays

    SciTech Connect (OSTI)

    Beushausen, Hans, E-mail: hans.beushausen@uct.ac.za; Chilwesa, Masuzyo

    2013-11-15T23:59:59.000Z

    Restrained drying shrinkage cracking was investigated on composite beams consisting of substrate concrete and bonded mortar overlays, and compared to the performance of the same mortars when subjected to the ring test. Stress development and cracking in the composite specimens were analytically modeled and predicted based on the measurement of relevant time-dependent material properties such as drying shrinkage, elastic modulus, tensile relaxation and tensile strength. Overlay cracking in the composite beams could be very well predicted with the analytical model. The ring test provided a useful qualitative comparison of the cracking performance of the mortars. The duration of curing was found to only have a minor influence on crack development. This was ascribed to the fact that prolonged curing has a beneficial effect on tensile strength at the onset of stress development, but is in the same time not beneficial to the values of tensile relaxation and elastic modulus. -- Highlights: •Parameter study on material characteristics influencing overlay cracking. •Analytical model gives good quantitative indication of overlay cracking. •Ring test presents good qualitative indication of overlay cracking. •Curing duration has little effect on overlay cracking.

  8. Effects of weld residual stresses on crack-opening area analysis of pipes for LBB applications

    SciTech Connect (OSTI)

    Dong, P.; Rahman, S.; Wilkowski, G. [and others

    1997-04-01T23:59:59.000Z

    This paper summarizes four different studies undertaken to evaluate the effects of weld residual stresses on the crack-opening behavior of a circumferential through-wall crack in the center of a girth weld. The effect of weld residual stress on the crack-opening-area and leak-rate analyses of a pipe is not well understood. There are no simple analyses to account for these effects, and, therefore, they are frequently neglected. The four studies involved the following efforts: (1) Full-field thermoplastic finite element residual stress analyses of a crack in the center of a girth weld, (2) A comparison of the crack-opening displacements from a full-field thermoplastic residual stress analysis with a crack-face pressure elastic stress analysis to determine the residual stress effects on the crack-opening displacement, (3) The effects of hydrostatic testing on the residual stresses and the resulting crack-opening displacement, and (4) The effect of residual stresses on crack-opening displacement with different normal operating stresses.

  9. Status Report on Studies of Recovery Boiler Composite Floor Tube Cracking

    SciTech Connect (OSTI)

    Eng, P.; Frederick, L.A.; Hoffmann, C.M.; Keiser, J.R.; Mahmood, J.; Maziasz, P.J.; Prescott, R.; Sarma, G.B.; Singbeil, D.L.; Singh, P.M.; Swindeman, R.W.; Wang, X.-L.

    1999-09-12T23:59:59.000Z

    Cracking of the stainless steel layer of co-extruded 304L stainless steel/SA210 Gd A 1 carbon steel black liquor recovery boiler floor tubes has been identified as one of the most serious material problems in the pulp and paper industry. A DOE-funded study was initiated in 1995 with the goal of determining the cause of and possible solutions to this cracking problem. These studies have characterized tube cracking as well as the chemical and thermal environment and stress state of floor tubes. Investigations of possible cracking mechanisms indicate that stress corrosion cracking rather than thermal fatigue is a more likely cause of crack initiation. The cracking mechanism appears to require the presence of hydrated sodium sulfide and is most likely active during shut-downs and/or start-ups. Based on these results and operating experience, certain alloys appear to be more resistant than others to cracking in the floor environment, and certain operating practices appear to significantly lessen the likelihood of cracking. This report is the latest in a series of progress reports presented on this project.

  10. Mixed Mode Static and Fatigue Crack Growth in Wind Blade Paste Adhesives

    E-Print Network [OSTI]

    , static GIc and mixed mode fracture, and fatigue crack growth resistance. I. Introduction Wind turbine blades are large composite structures which are typically resin infusion molded in sections

  11. Standard test method for measurement of creep crack growth times in metals

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2007-01-01T23:59:59.000Z

    1.1 This test method covers the determination of creep crack growth (CCG) in metals at elevated temperatures using pre-cracked specimens subjected to static or quasi-static loading conditions. The time (CCI), t0.2 to an initial crack extension ?ai = 0.2 mm from the onset of first applied force and creep crack growth rate, ?a or da/dt is expressed in terms of the magnitude of creep crack growth relating parameters, C* or K. With C* defined as the steady state determination of the crack tip stresses derived in principal from C*(t) and Ct (1-14). The crack growth derived in this manner is identified as a material property which can be used in modeling and life assessment methods (15-25). 1.1.1 The choice of the crack growth correlating parameter C*, C*(t), Ct, or K depends on the material creep properties, geometry and size of the specimen. Two types of material behavior are generally observed during creep crack growth tests; creep-ductile (1-14) and creep-brittle (26-37). In creep ductile materials, where cr...

  12. Fluid system for controlling fluid losses during hydrocarbon recovery operations

    SciTech Connect (OSTI)

    Johnson, M.H.; Smejkal, K.D.

    1993-07-20T23:59:59.000Z

    A fluid system is described for controlling fluid losses during hydrocarbon recovery operations, comprising: water; a distribution of graded calcium carbonate particle sizes; and at least one modified lignosulfonate, which is a lignosulfonate modified by polymerizing it at least to an extent effective to reduce its water solubility.

  13. Studies Relevent to Catalytic Activation Co & other small Molecules

    SciTech Connect (OSTI)

    Ford, Peter C

    2005-02-22T23:59:59.000Z

    Detailed annual and triannual reports describing the progress accomplished during the tenure of this grant were filed with the Program Manager for Catalysis at the Office of Basic Energy Sciences. To avoid unnecessary duplication, the present report will provide a brief overview of the research areas that were sponsored by this grant and list the resulting publications and theses based on this DOE supported research. The scientific personnel participating in (and trained by) this grant's research are also listed. Research carried out under this DOE grant was largely concerned with the mechanisms of the homogeneous catalytic and photocatalytic activation of small molecules such as carbon monoxide, dihydrogen and various hydrocarbons. Much of the more recent effort has focused on the dynamics and mechanisms of reactions relevant to substrate carbonylations by homogeneous organometallic catalysts. A wide range of modern investigative techniques were employed, including quantitative fast reaction methodologies such as time-resolved optical (TRO) and time-resolved infrared (TRIR) spectroscopy and stopped flow kinetics. Although somewhat diverse, this research falls within the scope of the long-term objective of applying quantitative techniques to elucidate the dynamics and understand the principles of mechanisms relevant to the selective and efficient catalytic conversions of fundamental feedstocks to higher value materials.

  14. Catalytic combustor for integrated gasification combined cycle power plant

    DOE Patents [OSTI]

    Bachovchin, Dennis M. (Mauldin, SC); Lippert, Thomas E. (Murrysville, PA)

    2008-12-16T23:59:59.000Z

    A gasification power plant 10 includes a compressor 32 producing a compressed air flow 36, an air separation unit 22 producing a nitrogen flow 44, a gasifier 14 producing a primary fuel flow 28 and a secondary fuel source 60 providing a secondary fuel flow 62 The plant also includes a catalytic combustor 12 combining the nitrogen flow and a combustor portion 38 of the compressed air flow to form a diluted air flow 39 and combining at least one of the primary fuel flow and secondary fuel flow and a mixer portion 78 of the diluted air flow to produce a combustible mixture 80. A catalytic element 64 of the combustor 12 separately receives the combustible mixture and a backside cooling portion 84 of the diluted air flow and allows the mixture and the heated flow to produce a hot combustion gas 46 provided to a turbine 48. When fueled with the secondary fuel flow, nitrogen is not combined with the combustor portion.

  15. On the approximation of crack shapes found during inservice inspection

    SciTech Connect (OSTI)

    Bhate, S.R.; Chawla, D.S.; Kushwaha, H.S. [Bhabha Atomic Research Centre, Bombay (India)] [and others

    1997-04-01T23:59:59.000Z

    This paper addresses the characterization of axial internal flaw found during inservice inspection of a pipe. J-integral distribution for various flaw shapes is obtained using line spring finite, element method. The peak J-value and its distribution across the crack is found to be characteristic feature of each shape. The triangular shape yields peak J-value away from the center, the point of depth. The elliptic approximation results in large overestimate of J-value for unsymmetric flaws. Triangular approximation is recommended for such flaws so that further service can be obtained from the component.

  16. Methodology for predicting asphalt concrete overlay life against reflection cracking

    E-Print Network [OSTI]

    Jayawickrama, Priyantha Warnasuriya

    1985-01-01T23:59:59.000Z

    of thermal expansion = change in temperature E K - (so gT) vc/h F3(c/h) +(I-u ) By defining, !40) (41) Jc/h F3(c/h) T Kt (42 ) 29 ~Summa r The proper variables to be used in a design equation and the form of the equation to be used is best... obtained are presented in this chapter. The stress intensity factor computations were carr1ed out for different crack-tip positions and for different levels of aggregate interlock act1on. These results were obtained for each of the three mechanisms...

  17. Nonlinear FE analysis of cracks in tension and shear

    E-Print Network [OSTI]

    Kesse, G.; Lees, Janet M.

    2007-05-01T23:59:59.000Z

    Carbon FRP Shear Reinforcement. PhD thesis, University of Cambridge, UK, 2003. 3. Bazant Z. P. and Planas J. Fracture and Size Effect in Con- crete and Other Quasibrittle Materials. CRC Press, Boca Raton, Florida, 1998. Nonlinear FE analysis of cracks... of plain concrete to cyclic tension. ACI Materials Journal, 1987, 84, No. 5, 365–373. 9. Paulay T. and Loeber P. J. Shear transfer by aggregate inter- lock. ACI Special Publication, SP-42, 1974, 1, 1–14. 10. Houde J. and Mirza M. S. A finite element...

  18. Catalytic oxidation of CO by platinum group metals: from ultrahigh vacuum to elevated pressures

    E-Print Network [OSTI]

    Goodman, Wayne

    oxidation over platinum group metals has been investigated for some eight decades by many researchersCatalytic oxidation of CO by platinum group metals: from ultrahigh vacuum to elevated pressures A Catalytic oxidation of CO over platinum group metals (Pt, Ir, Rh and Pd) has been the subject of many

  19. Micro Catalytic Combustor with Pd/Nano-porous Alumina for High-Temperature Application

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    Micro Catalytic Combustor with Pd/Nano-porous Alumina for High-Temperature Application Takashi: A micro-scale catalytic combustor using high-precision ceramic tape-casting technology has been developed surface reaction of butane. In combustion experiments with a prototype combustor, the wall temperature

  20. Non-uniform Heat Generation in Micro Catalytic Combustor Takashi Okamasa*, Yuji Suzuki, and Nobuhide Kasagi

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    Non-uniform Heat Generation in Micro Catalytic Combustor Takashi Okamasa*, Yuji Suzuki@thtlab.t.u-tokyo.ac.jp Abstract We developed a micro catalytic combustor using high-precision ceramic tape-casting technology and nano-porous alumina catalyst layer. It is found that failure of the ceramic combustor occurs due

  1. Control of Natural Gas Catalytic Partial Oxidation for Hydrogen Generation in Fuel Cell Applications1

    E-Print Network [OSTI]

    Peng, Huei

    Control of Natural Gas Catalytic Partial Oxidation for Hydrogen Generation in Fuel Cell the anode field of fuel cell stack is considered. The first reactor that generates the majority in the fuel cell anode and (ii) the temperature of the catalytic partial oxidation reactor during transient

  2. Catalytic Transformation of Toluene over High Acidity Y-Zeolite Based S. Al-Khattaf*

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    Catalytic Transformation of Toluene over High Acidity Y-Zeolite Based Catalyst S. Al Abstract Catalytic transformation of toluene has been investigated over Y-zeolite based catalysts in the temperature range of 400-500o C to understand the transformation of toluene over high acidity Y-based zeolite

  3. Multiscale Modeling and Solution Multiplicity in Catalytic Pellet Reactors Kedar Kulkarni,

    E-Print Network [OSTI]

    Linninger, Andreas A.

    Multiscale Modeling and Solution Multiplicity in Catalytic Pellet Reactors Kedar Kulkarni, Jeonghwa phenomena in catalytic pellet reactors are often difficult to analyze because of coupling between heat at the macroscopic level as well as the catalyst pellets at the microscopic level. The resulting approach yields

  4. ENGINEERING SCALE UP OF RENEWABLE HYDROGEN PRODUCTION BY CATALYTIC STEAM REFORMING OF PEANUT

    E-Print Network [OSTI]

    ENGINEERING SCALE UP OF RENEWABLE HYDROGEN PRODUCTION BY CATALYTIC STEAM REFORMING OF PEANUT SHELLS, and academic organizations is developing a steam reforming process to be demonstrated on the gaseous byproducts, catalytic, steam-reforming reactor was then successfully operated on methane and peanut shell pyrolysis

  5. MEMS-based fuel cells with integrated catalytic fuel processor and method thereof

    DOE Patents [OSTI]

    Jankowski, Alan F. (Livermore, CA); Morse, Jeffrey D. (Martinez, CA); Upadhye, Ravindra S. (Pleasanton, CA); Havstad, Mark A. (Davis, CA)

    2011-08-09T23:59:59.000Z

    Described herein is a means to incorporate catalytic materials into the fuel flow field structures of MEMS-based fuel cells, which enable catalytic reforming of a hydrocarbon based fuel, such as methane, methanol, or butane. Methods of fabrication are also disclosed.

  6. The Catalytic Chemistry of HCN+NO over Na- and Ba-Y, FAU: An...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The Catalytic Chemistry of HCN+NO over Na- and Ba-Y, FAU: An In Situ FTIR and TPDTPR Study. The Catalytic Chemistry of HCN+NO over Na- and Ba-Y, FAU: An In Situ FTIR and TPDTPR...

  7. Burning Velocities in Catalytically Assisted Self-Propagating High-Temperature Combustion Synthesis Systems

    E-Print Network [OSTI]

    Wooldridge, Margaret S.

    Burning Velocities in Catalytically Assisted Self-Propagating High-Temperature Combustion Synthesis of catalytically assisted self-propagating high-temperature synthesis (SHS) of the tantalum/carbon material system. © 2001 by The Combustion Institute INTRODUCTION Self-propagating high-temperature combustion synthesis

  8. Spin and Madelung fluid

    E-Print Network [OSTI]

    G. Salesi

    2009-06-23T23:59:59.000Z

    Starting from the Pauli current we obtain the decomposition of the non-relativistic local velocity in two parts: one parallel and the other orthogonal to the momentum. The former is recognized to be the ``classical'' part, that is the velocity of the center-of-mass, and the latter the ``quantum'' one, that is the velocity of the motion in the center-of-mass frame (namely, the internal ``spin motion'' or {\\em Zitterbewegung}). Inserting the complete expression of the velocity into the kinetic energy term of the classical non-relativistic (i.e., Newtonian) Lagrangian, we straightforwardly derive the so-called ``quantum potential'' associated to the Madelung fluid. In such a way, the quantum mechanical behaviour of particles appears to be strictly correlated to the existence of spin and Zitterbewegung.

  9. Fluid jet electric discharge source

    DOE Patents [OSTI]

    Bender, Howard A. (Ripon, CA)

    2006-04-25T23:59:59.000Z

    A fluid jet or filament source and a pair of coaxial high voltage electrodes, in combination, comprise an electrical discharge system to produce radiation and, in particular, EUV radiation. The fluid jet source is composed of at least two serially connected reservoirs, a first reservoir into which a fluid, that can be either a liquid or a gas, can be fed at some pressure higher than atmospheric and a second reservoir maintained at a lower pressure than the first. The fluid is allowed to expand through an aperture into a high vacuum region between a pair of coaxial electrodes. This second expansion produces a narrow well-directed fluid jet whose size is dependent on the size and configuration of the apertures and the pressure used in the reservoir. At some time during the flow of the fluid filament, a high voltage pulse is applied to the electrodes to excite the fluid to form a plasma which provides the desired radiation; the wavelength of the radiation being determined by the composition of the fluid.

  10. Fracture behavior of short circumferentially surface-cracked pipe

    SciTech Connect (OSTI)

    Krishnaswamy, P.; Scott, P.; Mohan, R. [Battelle, Columbus, OH (United States)] [and others

    1995-11-01T23:59:59.000Z

    This topical report summarizes the work performed for the Nuclear Regulatory Comniission`s (NRC) research program entitled ``Short Cracks in Piping and Piping Welds`` that specifically focuses on pipes with short, circumferential surface cracks. The following details are provided in this report: (i) material property deteminations, (ii) pipe fracture experiments, (iii) development, modification and validation of fracture analysis methods, and (iv) impact of this work on the ASME Section XI Flaw Evaluation Procedures. The material properties developed and used in the analysis of the experiments are included in this report and have been implemented into the NRC`s PIFRAC database. Six full-scale pipe experiments were conducted during this program. The analyses methods reported here fall into three categories (i) limit-load approaches, (ii) design criteria, and (iii) elastic-plastic fracture methods. These methods were evaluated by comparing the analytical predictions with experimental data. The results, using 44 pipe experiments from this and other programs, showed that the SC.TNP1 and DPZP analyses were the most accurate in predicting maximum load. New Z-factors were developed using these methods. These are being considered for updating the ASME Section XI criteria.

  11. Pinning and Depinning of Crack Fronts in Heterogeneous Materials

    SciTech Connect (OSTI)

    Daguier, P.; Bouchaud, E. [O.N.E.R.A. (Oman), 29 Avenue de la Division Leclerc, B.P. 72, 92322 Chatillon Cedex (France)] [O.N.E.R.A. (Oman), 29 Avenue de la Division Leclerc, B.P. 72, 92322 Chatillon Cedex (France); Nghiem, B.; Creuzet, F. [Laboratoire CNRS/Saint-Gobain Surface du Verre et Interfaces, 39, Quai Lucien Lefranc, B.P. 135, 93303 Aubervilliers Cedex (France)] [Laboratoire CNRS/Saint-Gobain Surface du Verre et Interfaces, 39, Quai Lucien Lefranc, B.P. 135, 93303 Aubervilliers Cedex (France)

    1997-02-01T23:59:59.000Z

    The fatigue fracture surfaces of a metallic alloy and the stress corrosion fracture surfaces of a silicate glass are investigated as a function of crack velocity. It is shown that in both cases there are two self-affine fracture regimes. At large enough length scales, the universal roughness index {zeta}{approx_equal}0.78 is recovered. At smaller length scales, the roughness exponent is close to {zeta}{sub c}{approx_equal}0.50. The crossover length {xi}{sub c} separating these two regimes strongly depends on the material, and exhibits a power-law decrease with the measured crack velocity {xi}{sub c}{proportional_to}v{sup -{phi}}, with {phi}{approx_equal}1. The exponents {nu} and {beta} characterizing the dependence of {xi}{sub c} and v upon the pulling force are shown to be close to {nu}{approx_equal}2 and {beta}{approx_equal}2. {copyright} {ital 1997} {ital The American Physical Society}

  12. Residual stresses and stress corrosion cracking in pipe fittings

    SciTech Connect (OSTI)

    Parrington, R.J.; Scott, J.J.; Torres, F.

    1994-06-01T23:59:59.000Z

    Residual stresses can play a key role in the SCC performance of susceptible materials in PWR primary water applications. Residual stresses are stresses stored within the metal that develop during deformation and persist in the absence of external forces or temperature gradients. Sources of residual stresses in pipe fittings include fabrication processes, installation and welding. There are a number of methods to characterize the magnitude and orientation of residual stresses. These include numerical analysis, chemical cracking tests, and measurement (e.g., X-ray diffraction, neutron diffraction, strain gage/hole drilling, strain gage/trepanning, strain gage/section and layer removal, and acoustics). This paper presents 400 C steam SCC test results demonstrating that residual stresses in as-fabricated Alloy 600 pipe fittings are sufficient to induce SCC. Residual stresses present in as-fabricated pipe fittings are characterized by chemical cracking tests (stainless steel fittings tested in boiling magnesium chloride solution) and by the sectioning and layer removal (SLR) technique.

  13. Low-Cracking High-Performance Concrete (LC-HPC) Bridge Decks: Shrinkage-Reducing Admixtures, Internal Curing, and Cracking Performance

    E-Print Network [OSTI]

    Pendergrass, Ben Andrew

    2014-05-31T23:59:59.000Z

    ABSTRACT The development, construction, and evaluation of low-cracking high-performance concrete (LC-HPC) bridge decks is described based on laboratory tests of mixtures containing shrinkage-reducing admixtures and mineral admixtures in conjunction...

  14. Finite element simulation of electrorheological fluids

    E-Print Network [OSTI]

    Rhyou, Chanryeol, 1973-

    2005-01-01T23:59:59.000Z

    Electrorheological (ER) fluids change their flow properties dramatically when an electric field is applied. These fluids are usually composed of dispersions of polarizable particles in an insulating base fluid or composed ...

  15. Interaction between corrosion crack width and steel loss in RC beams corroded under load

    SciTech Connect (OSTI)

    Malumbela, Goitseone, E-mail: malumbela@mopipi.ub.b [Dpt. of Civil Eng., Univ. of Cape Town, Private Bag X3, Rondebosch, 7700 (South Africa); Alexander, Mark; Moyo, Pilate [Dpt. of Civil Eng., Univ. of Cape Town, Private Bag X3, Rondebosch, 7700 (South Africa)

    2010-09-15T23:59:59.000Z

    This paper presents results and discussions on an experimental study conducted to relate the rate of widening of corrosion cracks with the pattern of corrosion cracks as well as the level of steel corrosion for RC beams (153 x 254 x 3000 mm) that were corroded whilst subjected to varying levels of sustained loads. Steel corrosion was limited to the tensile reinforcement and to a length of 700 mm at the centre of the beams. The rate of widening of corrosion cracks as well as strains on uncracked faces of RC beams was constantly monitored during the corrosion process, along the corrosion region and along other potential cracking faces of beams using a demec gauge. The distribution of the gravimetric mass loss of steel along the corrosion region was measured at the end of the corrosion process. The results obtained showed that: the rate of widening of each corrosion crack is dependent on the overall pattern of the cracks whilst the rate of corrosion is independent of the pattern of corrosion cracks. A mass loss of steel of 1% was found to induce a corrosion crack width of about 0.04 mm.

  16. Theory of thin-skin eddy-current interaction with surface cracks N. Harfielda)

    E-Print Network [OSTI]

    Bowler, John R.

    Theory of thin-skin eddy-current interaction with surface cracks N. Harfielda) and J. R. Bowler; accepted for publication 14 July 1997 Eddy-current non-destructive evaluation is commonly performed of a typical crack. A thin-skin analysis of eddy currents is presented in which the electromagnetic fields

  17. A NON-ISOTHERMAL FATIGUE CRACK GROWTH LAW FOR THE A356-T7 ALUMINUM ALLOY

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 A NON-ISOTHERMAL FATIGUE CRACK GROWTH LAW FOR THE A356-T7 ALUMINUM ALLOY E. Merhy 1,2,3* , L rate, Damage tolerant design, Life time prediction, A356 cast alloy ABSTRACT Fatigue crack growth period in cylinder heads of A356-T7 casting alloy has been found to constitute an important part

  18. Crack Detection in Dielectric Structures by a Linear Sampling , M. Brignone2

    E-Print Network [OSTI]

    Piana, Michele

    Crack Detection in Dielectric Structures by a Linear Sampling Approach G. Bozza1 , M. Brignone2 , M for the detection of cracks and defects inside dielectric structures is presented. The proposed algorithm is based of the approach is assessed by means of numerical simulations. 1. Introduction The imaging community

  19. Random sequential adsorption model of damage and crack accumulation: Exact one-dimensional results

    E-Print Network [OSTI]

    O. Gromenko; V. Privman; M. L. Glasser

    2008-04-29T23:59:59.000Z

    The random sequential adsorption (RSA) model is modified to describe damage and crack accumulation. The exclusion for object deposition (for damaged region formation) is not for the whole object, as in the standard RSA, but only for the initial point (or higher-dimensional defect) from which the damaged region or crack initiates. The one-dimensional variant of the model is solved exactly.

  20. THE ELASTIC-PLASTIC MECHANICS OF CRACK EXTENSION James R. Rice*

    E-Print Network [OSTI]

    THE ELASTIC-PLASTIC MECHANICS OF CRACK EXTENSION James R. Rice* ABSTRACT This paper briefly reviews progres~in the elastic plastic analysisof crack extension. Analytical results for plane strain and plane stress deformation fields are noted, and elastic-plastic fracture instability as well as transitional

  1. Analysis of the tube-sheet cracking in slurry oil steam , L.J. Qiao a,

    E-Print Network [OSTI]

    Volinsky, Alex A.

    -sheet cracking is a severe problem in the oil refinery industry with the consequences of shortened service life steam generator is a kind of shell and tube heat exchanger extensively used in the oil refinement in the oil refinery industry. Previous study has shown that corrosion, such as stress corrosion cracking (SCC

  2. Thermo-optical modulation for improved ultrasonic fatigue crack detection in Ti6Al4V

    E-Print Network [OSTI]

    Nagy, Peter B.

    scatterers, such as surface grooves, corrosion pits, coarse grains, etc. that might hide the fatigue crack to grow at unexpectedly high growth rates well below the large-crack threshold in aluminum, aluminum­lithium) and secondary irregulari- ties (e.g. uneven machining, mechanical wear, corrosion, etc.). Second

  3. Ultrasonic ply-by-ply detection of matrix cracks in laminated composites

    E-Print Network [OSTI]

    Ganpatye, Atul Shridatta

    2005-02-17T23:59:59.000Z

    on the internal damage state of the composite tank wall. Damage in the form of matrix cracks in the composite material of the tank is responsible for the through-the-thickness permeation of LH2. In this context, the detection of matrix cracks takes...

  4. A model for the ultrasonic detection of surface-breaking cracks by the Scanning

    E-Print Network [OSTI]

    Huerta, Antonio

    A model for the ultrasonic detection of surface-breaking cracks by the Scanning Laser Source, Northwestern University, Evanston, IL 60208, USA Abstract A model for the Scanning Laser Source (SLS) technique- breaking cracks. The generated ultrasonic signal is monitored as a line-focused laser is scanned over

  5. FREE-FORM ANISOTROPY: A NEW METHOD FOR CRACK DETECTION ON PAVEMENT SURFACE IMAGES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    FREE-FORM ANISOTROPY: A NEW METHOD FOR CRACK DETECTION ON PAVEMENT SURFACE IMAGES Tien Sy NGUYEN(1, in the segmentation step, for crack detection on road pavement images. Features which are calculated along every free on some samples of different kinds of pavements. Results of the method are also given on other kinds

  6. Prediction of reinforcement corrosion using corrosion induced cracks width in corroded reinforced concrete beams

    SciTech Connect (OSTI)

    Khan, Inamullah; François, Raoul [Université de Toulouse, UPS, INSA, LMDC (Laboratoire Matériaux et Durabilité des Constructions), 135, Avenue de Rangueil, F-31077 Toulouse (France)] [Université de Toulouse, UPS, INSA, LMDC (Laboratoire Matériaux et Durabilité des Constructions), 135, Avenue de Rangueil, F-31077 Toulouse (France); Castel, Arnaud [Centre for Infrastructure Engineering and Safety, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW (Australia)] [Centre for Infrastructure Engineering and Safety, School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW (Australia)

    2014-02-15T23:59:59.000Z

    This paper studies the evolution of reinforcement corrosion in comparison to corrosion crack width in a highly corroded reinforced concrete beam. Cracking and corrosion maps of the beam were drawn and steel reinforcement was recovered from the beam to observe the corrosion pattern and to measure the loss of mass of steel reinforcement. Maximum steel cross-section loss of the main reinforcement and average steel cross-section loss between stirrups were plotted against the crack width. The experimental results were compared with existing models proposed by Rodriguez et al., Vidal et al. and Zhang et al. Time prediction models for a given opening threshold are also compared to experimental results. Steel cross-section loss for stirrups was also measured and was plotted against the crack width. It was observed that steel cross-section loss in the stirrups had no relationship with the crack width of longitudinal corrosion cracks. -- Highlights: •Relationship between crack and corrosion of reinforcement was investigated. •Corrosion results of natural process and then corresponds to in-situ conditions. •Comparison with time predicting model is provided. •Prediction of load-bearing capacity from crack pattern was studied.

  7. Robust damage assessment of multiple cracks based on the Frequency Response Function and the Constitutive Relation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Robust damage assessment of multiple cracks based on the Frequency Response Function a damage assessment technique for the non destructive detection and sizing of multiple open cracks in beams, many researchers have performed extensive investigations and damage assess- ment techniques based

  8. Effect of Blast Design on Crack Response C.H. Dowding

    E-Print Network [OSTI]

    Effect of Blast Design on Crack Response C.H. Dowding Professor of Civil & Environmental to assess the effect of changes in blast design on the house response. Velocity response was measured some 11 velocity transducers and 3 crack sensors measured excitation and response for each blast

  9. Assessing Hydrogen-Assisted Cracking Fracture Modes in High-Strength

    E-Print Network [OSTI]

    Eagar, Thomas W.

    I I Ii . I f. Assessing Hydrogen-Assisted Cracking Fracture Modes in High-Strength Steel Weldments Test results substantiate and extend the Beachem theory on hydrogen embrittlement ABSTRACT of the hydrogen content at the crack loca- tion. This relationship was used to assess previously proposed

  10. ccsd-00095604,version1-18Sep2006 Understanding crack versus cavitation in pressure-sensitive

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ccsd-00095604,version1-18Sep2006 Understanding crack versus cavitation in pressure show that in addition to cavitation, interfacial cracks are encountered in a probe-tack traction test mechanisms in usual adhesives. The most common one is cavitation, as evidenced by the first tests

  11. Hot-crack test for aluminium alloys welds using TIG process , F. Deschaux1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hot-crack test for aluminium alloys welds using TIG process A. Niel1,a , F. Deschaux1 , C cracking in welds : state of art Aluminium alloys are highly sensitive to hot tearing phenomenon. It appears during solidification of the alloy, so it can be observed during welding, as well as during

  12. WATTS TOWERS: THE EFFECTS OF THERMAL CYCLES ON THE FORMATION AND BEHAVIOR OF CRACKS

    E-Print Network [OSTI]

    Spencer, Matthew T

    2013-02-06T23:59:59.000Z

    The development of cracks in Portland Cement Concrete (PCC) and Grout has become a problem of rising concern in a country with an aging infrastructure. A detailed understanding of the causes as well as the behavior of these cracks is vital...

  13. Reflective Cracking Study: First-level Report on HVS Testing on Section 586RF - 45 mm MB15-GOverlay

    E-Print Network [OSTI]

    Jones, David; Wu, R; Harvey, John T

    2008-01-01T23:59:59.000Z

    of the asphalt concrete layer. Testing was stopped when thetesting being performed to validate Caltrans overlay strategies for the rehabilitation of cracked asphalt concrete.concrete. It describes the results of the fifth HVS reflective cracking testing

  14. Reflective Cracking Study: First-Level Report on HVS Testing on Section 589RF - 45 mm MB4-G Overlay

    E-Print Network [OSTI]

    Jones, David; Harvey, John T; Wu, R; Lea, J.

    2008-01-01T23:59:59.000Z

    of the asphalt concrete layer. Testing was stopped when thetesting being performed to validate Caltrans overlay strategies for the rehabilitation of cracked asphalt concrete.concrete. It describes the results of the second HVS reflective cracking testing

  15. Efficient solution of multiple cracks in great number using eigen COD boundary integral equations with iteration procedure

    E-Print Network [OSTI]

    Liu, Yijun

    as the fibre-reinforced brittle materials after certain extent of tensile damage. The prediction of crack in an infinite domain under fictitious traction acting on the crack surface. With the concept of eigen COD

  16. Computational fluid dynamic modeling of fluidized-bed polymerization reactors

    SciTech Connect (OSTI)

    Rokkam, Ram [Ames Laboratory

    2012-11-02T23:59:59.000Z

    Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.

  17. Studies of coupled chemical and catalytic coal conversion methods

    SciTech Connect (OSTI)

    Stock, L.M.; Chatterjee, K.; Cheng, C.; Ettinger, M.; Flores, F.; Jiralerspong, S.; Miyake, M.; Muntean, J.

    1991-12-01T23:59:59.000Z

    The objective of this research was to convert coal into a soluble substance under mild conditions. The strategy involved two steps, first to breakdown the macromolecular network of coal, and second to add hydrogen catalytically. We investigated different basic reagents that could, in priciple, break down coal's structure and alkylation strategies that might enhance its solubility. We examined O- and C-alkylation, the importance of the strength of the base, the character of the added alkyl groups and other reaction parameters. This work provided new information concerning the way in which hydrogen bonding, polarization interactions between aromatic structures and covalent bonding could be disrupted and solubility enhanced. The objective of our research was to explore new organochromium chemistry that might be feasible for the hydrogenation of coal under mild conditions.

  18. Studies of coupled chemical and catalytic coal conversion methods

    SciTech Connect (OSTI)

    Stock, L.M.; Chatterjee, K.; Cheng, C.; Ettinger, M.; Flores, F.; Jiralerspong, S.; Miyake, M.; Muntean, J.

    1991-12-01T23:59:59.000Z

    The objective of this research was to convert coal into a soluble substance under mild conditions. The strategy involved two steps, first to breakdown the macromolecular network of coal, and second to add hydrogen catalytically. We investigated different basic reagents that could, in priciple, break down coal`s structure and alkylation strategies that might enhance its solubility. We examined O- and C-alkylation, the importance of the strength of the base, the character of the added alkyl groups and other reaction parameters. This work provided new information concerning the way in which hydrogen bonding, polarization interactions between aromatic structures and covalent bonding could be disrupted and solubility enhanced. The objective of our research was to explore new organochromium chemistry that might be feasible for the hydrogenation of coal under mild conditions.

  19. In-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect (OSTI)

    Biddy, Mary J.; Dutta, Abhijit; Jones, Susanne B.; Meyer, Pimphan A.

    2013-03-31T23:59:59.000Z

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline, diesel, and jet range blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  20. Ex-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect (OSTI)

    Biddy, Mary J.; Dutta, Abhijit; Jones, Susanne B.; Meyer, Pimphan A.

    2013-03-31T23:59:59.000Z

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline , diesel and jet range blendstocks . Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  1. Coal hydrogenation and deashing in ebullated bed catalytic reactor

    DOE Patents [OSTI]

    Huibers, Derk T. A. (Pennington, NJ); Johanson, Edwin S. (Princeton, NJ)

    1983-01-01T23:59:59.000Z

    An improved process for hydrogenation of coal containing ash with agglomeration and removal of ash from an ebullated bed catalytic reactor to produce deashed hydrocarbon liquid and gas products. In the process, a flowable coal-oil slurry is reacted with hydrogen in an ebullated catalyst bed reaction zone at elevated temperature and pressure conditions. The upward velocity and viscosity of the reactor liquid are controlled so that a substantial portion of the ash released from the coal is agglomerated to form larger particles in the upper portion of the reactor above the catalyst bed, from which the agglomerated ash is separately withdrawn along with adhering reaction zone liquid. The resulting hydrogenated hydrocarbon effluent material product is phase separated to remove vapor fractions, after which any ash remaining in the liquid fraction can be removed to produce substantially ash-free coal-derived liquid products.

  2. Catalytic Hydrogenation of Bio-Oil for Chemicals and Fuels

    SciTech Connect (OSTI)

    Elliott, Douglas C.

    2006-02-14T23:59:59.000Z

    The scope of work includes optimizing processing conditions and demonstrating catalyst lifetime for catalyst formulations that are readily scaleable to commercial operations. We use a bench-scale, continuous-flow, packed-bed, catalytic, tubular reactor, which can be operated in the range of 100-400 mL/hr., from 50-400 C and up to 20MPa (see Figure 1). With this unit we produce upgraded bio-oil from whole bio-oil or useful bio-oil fractions, specifically pyrolytic lignin. The product oils are fractionated, for example by distillation, for recovery of chemical product streams. Other products from our tests have been used in further testing in petroleum refining technology at UOP and fractionation for product recovery in our own lab. Further scale-up of the technology is envisioned and we will carry out or support process design efforts with industrial partners, such as UOP.

  3. Methods and apparatus for catalytic hydrothermal gasification of biomass

    DOE Patents [OSTI]

    Elliott, Douglas C.; Butner, Robert Scott; Neuenschwander, Gary G.; Zacher, Alan H.; Hart, Todd R.

    2012-08-14T23:59:59.000Z

    Continuous processing of wet biomass feedstock by catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent separation of sulfur contaminants, or combinations thereof. Treatment further includes separating the precipitates out of the wet feedstock, removing sulfur contaminants, or both using a solids separation unit and a sulfur separation unit, respectively. Having removed much of the inorganic wastes and the sulfur that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.

  4. Catalytic carbon membranes for hydrogen production. Final report

    SciTech Connect (OSTI)

    Damle, A.S.; Gangwal, S.K.

    1992-01-01T23:59:59.000Z

    Commercial carbon composite microfiltration membranes may be modified for gas separation applications by providing a gas separation layer with pores in the 1- to 10-nm range. Several organic polymeric precursors and techniques for depositing a suitable layer were investigated in this project. The in situ polymerization technique was found to be the most promising, and pure component permeation tests with membrane samples prepared with this technique indicated Knudsen diffusion behavior. The gas separation factors obtained by mixed-gas permeation tests were found to depend strongly on gas temperature and pressure indicating significant viscous flow at high-pressure conditions. The modified membranes were used to carry out simultaneous water gas shift reaction and product hydrogen separation. These tests indicated increasing CO conversions with increasing hydrogen separation. A simple process model was developed to simulate a catalytic membrane reactor. A number of simulations were carried out to identify operating conditions leading to product hydrogen concentrations over 90 percent. (VC)

  5. Tantalum pillard montmorillonite: II. Acidic and catalytic properties

    SciTech Connect (OSTI)

    Guiu, G.; Grange, P. [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)] [Universite Catholique de Louvain, Louvain-la-Neuve (Belgium)

    1997-06-01T23:59:59.000Z

    The acidic and catalytic properties of a series of Ta-PILCs synthesized with a different initial tantalum content were characterized by adsorption of gaseous probe molecules (TPD of ammonia and FTIR spectra of absorbed pyridine) and by the test reaction of 1-butanol dehydration. A large increase of acidity was noted in Ta-PILCs compared to Na-montmorillonite or tantalum oxide. Cross-linking pillars and silica layers of the clay induce stronger Lewis and new Bronsted sites. The lack of basic sites formation is evidenced by the dehydration of 1-butanol to butene selectivity (100%). The incorporation of the tantalum oxide between the montmorillonite sheets produce, within Ta-PILC, acid centers of the same nature as observed for the silicon-tantalum mixed oxides. 32 refs., 4 figs., 5 tabs.

  6. Model catalytic oxidation studies using supported monometallic and heterobimetallic oxides

    SciTech Connect (OSTI)

    Ekerdt, J.G.

    1991-04-30T23:59:59.000Z

    This research program is directed toward developing a fundamental understanding of how catalyst composition, redox ability, and structure control the catalytic properties of metal oxides. Oxide systems that permit examination of the role of metal oxide cations separately and in pairwise combinations are being developed. Organometallic complexes containing C{sub 3}-allyl, cyclopentadienyl, or carbonyl ligands are exchanged with the hydroxide ligands of silica, alumina, titania, zirconia and magnesia supports. The exchange technique is used to achieve high metal oxide loadings without the formation of supported crystallites over silica. The organometallic route may also lead to oxygen-bridged cations and/or cation pairs over the supports prior to full oxidation. The anchored complex is subsequently oxidized to generate a supported oxide. 2 refs., 1 tab.

  7. Method for selective catalytic reduction of nitrogen oxides

    DOE Patents [OSTI]

    Mowery-Evans, Deborah L. (Broomfield, CO); Gardner, Timothy J. (Albuquerque, NM); McLaughlin, Linda I. (Albuquerque, NM)

    2005-02-15T23:59:59.000Z

    A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

  8. Method For Selective Catalytic Reduction Of Nitrogen Oxides

    DOE Patents [OSTI]

    Mowery-Evans, Deborah L. (Broomfield, CO); Gardner, Timothy J. (Albuquerque, NM); McLaughlin, Linda I. (Albuquerque, NM)

    2005-02-15T23:59:59.000Z

    A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

  9. Fabrication of fuel cell electrodes and other catalytic structures

    DOE Patents [OSTI]

    Smith, J.L.

    1987-02-11T23:59:59.000Z

    A porous layer of catalyst material suitable for use as an electrode in a molten carbonate fuel cell includes elongated pores substantially extending across the layer thickness. The catalyst layer is prepared by depositing particulate catalyst material into polymeric flocking on a substrate surface by a procedure such as tape casting. The loaded substrate is heated in a series of steps with rising temperatures to set the tape, thermally decompose the substrate with flocking and sinter bond the catalyst particles into a porous catalytic layer with elongated pores across its thickness. Employed as an electrode, the elongated pores provide distribution of reactant gas into contact with catalyst particles wetted by molten electrolyte. 1 fig.

  10. Vickers microindentation toughness of a sintered SiC in the median-crack regime

    SciTech Connect (OSTI)

    Ghosh, Asish; Kobayashi, A.S. (Washington Univ., Seattle, WA (United States). Coll. of Engineering); Li, Zhuang (Argonne National Lab., IL (United States)); Henager, C.H. Jr. (Pacific Northwest Lab., Richland, WA (United States)); Bradt, R.C. (Nevada Univ., Reno, NV (United States). Mackay School of Mines)

    1991-01-01T23:59:59.000Z

    The Vickers microindentation method for the determination of the fracture toughness of ceramics was investigated in the median crack regime for a sintered alpha SiC. The results are compared with fracture toughness measurements by conventional fracture mechanics technique and also with the reported indentation toughness for the low-load Palmqvist crack regime. Indentation toughnesses in the median crack regime vary widely depending on the choice of the specific equation which is applied. The indentation toughnesses are also load (crack length) dependent. A decreasing R-curve trend results, in contradiction to the flat R-curve that has been observed with conventional fracture mechanics techniques. It is concluded that the Vickers microindentation method is not a reliable technique for the determination of the fracture toughness of ceramics in the median crack regime.

  11. Enlargement of concrete blocks of arch dams with allowance of the formation of radial thermal cracks

    SciTech Connect (OSTI)

    Verbetskii, G.P.; Chogovadze, G.I.; Daneliya, A.I.

    1988-04-01T23:59:59.000Z

    Considerable acceleration of the construction of arch dams with the use of highly productive continuous concreting mechanisms is possible with enlargement of the blocks and allowance of the formation of thermal radial cracks in them. A theoretical analysis and the results of on-site observations show that under the effect of the hydrostatic head of water, radial joints and cracks in compressed zones of an arch dam close and the dam in these zones works as a solid dam. Thermal cracking in concrete blocks of arch dams enlarged in plan should be controlled by making radial notches to concentrate tensile stresses providing the formation of radial cracks at prescribed places and through the usual methods of thermal regulation. The block size along the face of an arch dam is then no longer limited by the condition of crack resistance but is determined by the rate of concreting. The technical and economic effects from concreting arch dams are cited.

  12. Fatigue crack propagation in a quasi one-dimensional elasto-plastic model

    E-Print Network [OSTI]

    Tomás M. Guozden; Eduardo A. Jagla

    2012-06-27T23:59:59.000Z

    Fatigue crack advance induced by the application of cyclic quasistatic loads is investigated both numerically and analytically using a lattice spring model. The system has a quasi-one-dimensional geometry, and consists in two symmetrical chains that are pulled apart, thus breaking springs which connect them, and producing the advance of a crack. Quasistatic crack advance occurs as a consequence of the plasticity included in the springs which form the chains, and that implies a history dependent stress-strain curve for each spring. The continuous limit of the model allows a detailed analytical treatment that gives physical insight of the propagation mechanism. This simple model captures key features that cause well known phenomenology in fatigue crack propagation, in particular a Paris-like law of crack advance under cyclic loading, and the overload retardation effect.

  13. Variable flexure-based fluid filter

    DOE Patents [OSTI]

    Brown, Steve B.; Colston Jr., Billy W.; Marshall, Graham; Wolcott, Duane

    2007-03-13T23:59:59.000Z

    An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.

  14. Fluid Imaging of Enhanced Geothermal Systems

    Broader source: Energy.gov (indexed) [DOE]

    for Fluids & Fractures - time lapse MTCSEM for fluid imaging - joint CSEM-MTseismic imaging ??? - use MEQ focal information with EM Imaging ScientificTechnical Approach...

  15. Catalytic Synthesis of Oxygenates: Mechanisms, Catalysts and Controlling Characteristics

    SciTech Connect (OSTI)

    Kamil Klier; Richard G. Herman

    2005-11-30T23:59:59.000Z

    This research focused on catalytic synthesis of unsymmetrical ethers as a part of a larger program involving oxygenated products in general, including alcohols, ethers, esters, carboxylic acids and their derivatives that link together environmentally compliant fuels, monomers, and high-value chemicals. The catalysts studied here were solid acids possessing strong Br�������¸nsted acid functionalities. The design of these catalysts involved anchoring the acid groups onto inorganic oxides, e.g. surface-grafted acid groups on zirconia, and a new class of mesoporous solid acids, i.e. propylsulfonic acid-derivatized SBA-15. The former catalysts consisted of a high surface concentration of sulfate groups on stable zirconia catalysts. The latter catalyst consists of high surface area, large pore propylsulfonic acid-derivatized silicas, specifically SBA-15. In both cases, the catalyst design and synthesis yielded high concentrations of acid sites in close proximity to one another. These materials have been well-characterization in terms of physical and chemical properties, as well as in regard to surface and bulk characteristics. Both types of catalysts were shown to exhibit high catalytic performance with respect to both activity and selectivity for the bifunctional coupling of alcohols to form ethers, which proceeds via an efficient SN2 reaction mechanism on the proximal acid sites. This commonality of the dual-site SN2 reaction mechanism over acid catalysts provides for maximum reaction rates and control of selectivity by reaction conditions, i.e. pressure, temperature, and reactant concentrations. This research provides the scientific groundwork for synthesis of ethers for energy applications. The synthesized environmentally acceptable ethers, in part derived from natural gas via alcohol intermediates, exhibit high cetane properties, e.g. methylisobutylether with cetane No. of 53 and dimethylether with cetane No. of 55-60, or high octane properties, e.g. diisopropylether with blending octane No. of 105, and can replace aromatics in liquid fuels.

  16. Detachment Energies of Spheroidal Particles from Fluid-Fluid Interfaces

    E-Print Network [OSTI]

    Gary B. Davies; Timm Krüger; Peter V. Coveney; Jens Harting

    2014-10-28T23:59:59.000Z

    The energy required to detach a single particle from a fluid-fluid interface is an important parameter for designing certain soft materials, for example, emulsions stabilised by colloidal particles, colloidosomes designed for targeted drug delivery, and bio-sensors composed of magnetic particles adsorbed at interfaces. For a fixed particle volume, prolate and oblate spheroids attach more strongly to interfaces because they have larger particle-interface areas. Calculating the detachment energy of spheroids necessitates the difficult measurement of particle-liquid surface tensions, in contrast with spheres, where the contact angle suffices. We develop a simplified detachment energy model for spheroids which depends only on the particle aspect ratio and the height of the particle centre of mass above the fluid-fluid interface. We use lattice Boltzmann simulations to validate the model and provide quantitative evidence that the approach can be applied to simulate particle-stabilized emulsions, and highlight the experimental implications of this validation.

  17. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.

    1993-11-30T23:59:59.000Z

    A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.

  18. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)

    1993-01-01T23:59:59.000Z

    A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.

  19. Computational fluid dynamic applications

    SciTech Connect (OSTI)

    Chang, S.-L.; Lottes, S. A.; Zhou, C. Q.

    2000-04-03T23:59:59.000Z

    The rapid advancement of computational capability including speed and memory size has prompted the wide use of computational fluid dynamics (CFD) codes to simulate complex flow systems. CFD simulations are used to study the operating problems encountered in system, to evaluate the impacts of operation/design parameters on the performance of a system, and to investigate novel design concepts. CFD codes are generally developed based on the conservation laws of mass, momentum, and energy that govern the characteristics of a flow. The governing equations are simplified and discretized for a selected computational grid system. Numerical methods are selected to simplify and calculate approximate flow properties. For turbulent, reacting, and multiphase flow systems the complex processes relating to these aspects of the flow, i.e., turbulent diffusion, combustion kinetics, interfacial drag and heat and mass transfer, etc., are described in mathematical models, based on a combination of fundamental physics and empirical data, that are incorporated into the code. CFD simulation has been applied to a large variety of practical and industrial scale flow systems.

  20. Viscous dark fluid universe

    SciTech Connect (OSTI)

    Hipolito-Ricaldi, W. S. [Universidade Federal do Espirito Santo, Departamento de Ciencias Matematicas e Naturais, CEUNES, Rodovia BR 101 Norte, km. 60, CEP 29932-540, Sao Mateus, Espirito Santo (Brazil); Velten, H. E. S.; Zimdahl, W. [Universidade Federal do Espirito Santo, Departamento de Fisica, Av. Fernando Ferrari, 514, Campus de Goiabeiras, CEP 29075-910, Vitoria, Espirito Santo (Brazil)

    2010-09-15T23:59:59.000Z

    We investigate the cosmological perturbation dynamics for a universe consisting of pressureless baryonic matter and a viscous fluid, the latter representing a unified model of the dark sector. In the homogeneous and isotropic background the total energy density of this mixture behaves as a generalized Chaplygin gas. The perturbations of this energy density are intrinsically nonadiabatic and source relative entropy perturbations. The resulting baryonic matter power spectrum is shown to be compatible with the 2dFGRS and SDSS (DR7) data. A joint statistical analysis, using also Hubble-function and supernovae Ia data, shows that, different from other studies, there exists a maximum in the probability distribution for a negative present value q{sub 0{approx_equal}}-0.53 of the deceleration parameter. Moreover, while previous descriptions on the basis of generalized Chaplygin-gas models were incompatible with the matter power-spectrum data since they required a much too large amount of pressureless matter, the unified model presented here favors a matter content that is of the order of the baryonic matter abundance suggested by big-bang nucleosynthesis.

  1. Fluid sampling system

    DOE Patents [OSTI]

    Houck, E.D.

    1994-10-11T23:59:59.000Z

    An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to be decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank. 4 figs.

  2. Fluid sampling system

    DOE Patents [OSTI]

    Houck, Edward D. (Idaho Falls, ID)

    1994-01-01T23:59:59.000Z

    An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank.

  3. Tracing Geothermal Fluids

    SciTech Connect (OSTI)

    Michael C. Adams; Greg Nash

    2004-03-01T23:59:59.000Z

    Geothermal water must be injected back into the reservoir after it has been used for power production. Injection is critical in maximizing the power production and lifetime of the reservoir. To use injectate effectively the direction and velocity of the injected water must be known or inferred. This information can be obtained by using chemical tracers to track the subsurface flow paths of the injected fluid. Tracers are chemical compounds that are added to the water as it is injected back into the reservoir. The hot production water is monitored for the presence of this tracer using the most sensitive analytic methods that are economically feasible. The amount and concentration pattern of the tracer revealed by this monitoring can be used to evaluate how effective the injection strategy is. However, the tracers must have properties that suite the environment that they will be used in. This requires careful consideration and testing of the tracer properties. In previous and parallel investigations we have developed tracers that are suitable from tracing liquid water. In this investigation, we developed tracers that can be used for steam and mixed water/steam environments. This work will improve the efficiency of injection management in geothermal fields, lowering the cost of energy production and increasing the power output of these systems.

  4. Linked multicontinuum and crack tensor approach for modeling of coupled geomechanics, fluid flow and transport in fractured rock

    E-Print Network [OSTI]

    Rutqvist, J.

    2014-01-01T23:59:59.000Z

    geomechanics in dual-porosity modeling of naturally fractured reservoirs. Society of Petroleum Engineers,

  5. EFFECT OF STRESS GRADIENT AT THE VICINITY OF A CRACK TIP ON IONIC DIFFUSION IN SILICATE GLASSES: AN AFM STUDY.

    E-Print Network [OSTI]

    Demouchy, Sylvie

    1 EFFECT OF STRESS GRADIENT AT THE VICINITY OF A CRACK TIP ON IONIC DIFFUSION IN SILICATE GLASSES.marliere@univ-montp2.fr ABSTRACT The slow advance of a crack in sodo-silicate glasses was studied at nanometer scale-micrometric vicinity of the tip of a crack running in silicate glass with mobile ions (as sodium cations) and check

  6. ensl-00156750,version1-22Jun2007 A dynamical law for slow crack growth in polycarbonate films

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ensl-00156750,version1-22Jun2007 A dynamical law for slow crack growth in polycarbonate films: 24 juin 2007) We study experimentally the slow growth of a single crack in polycarbonate films experimental insight in our plastic zone pz Fig. 1 ­ Image of a crack in a polycarbonate film with its

  7. Standardization of Thermo-Fluid Modeling in Modelica.Fluid

    SciTech Connect (OSTI)

    Franke, Rudiger; Casella, Francesco; Sielemann, Michael; Proelss, Katrin; Otter, Martin; Wetter, Michael

    2009-09-01T23:59:59.000Z

    This article discusses the Modelica.Fluid library that has been included in the Modelica Standard Library 3.1. Modelica.Fluid provides interfaces and basic components for the device-oriented modeling of onedimensional thermo-fluid flow in networks containing vessels, pipes, fluid machines, valves and fittings. A unique feature of Modelica.Fluid is that the component equations and the media models as well as pressure loss and heat transfer correlations are decoupled from each other. All components are implemented such that they can be used for media from the Modelica.Media library. This means that an incompressible or compressible medium, a single or a multiple substance medium with one or more phases might be used with one and the same model as long as the modeling assumptions made hold. Furthermore, trace substances are supported. Modeling assumptions can be configured globally in an outer System object. This covers in particular the initialization, uni- or bi-directional flow, and dynamic or steady-state formulation of mass, energy, and momentum balance. All assumptions can be locally refined for every component. While Modelica.Fluid contains a reasonable set of component models, the goal of the library is not to provide a comprehensive set of models, but rather to provide interfaces and best practices for the treatment of issues such as connector design and implementation of energy, mass and momentum balances. Applications from various domains are presented.

  8. Insertable fluid flow passage bridgepiece and method

    DOE Patents [OSTI]

    Jones, Daniel O. (Glenville, NV)

    2000-01-01T23:59:59.000Z

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  9. Specified pipe fittings susceptible to sulfide stress cracking

    SciTech Connect (OSTI)

    McIntyre, D.R.; Moore, E.M. Jr. [Saudi Aramco, Dhahran (Saudi Arabia)

    1996-01-01T23:59:59.000Z

    The NACE Standard MR0175 limit of HRC 22 is too high for cold-forged and stress-relieved ASTM A234 WPB pipe fittings. Hardness surveys and sulfide stress cracking test results per ASTM G 39 and NACE TM0177 Method B are presented to support this contention. More stringent inspection and a hardness limit of HB 197 (for cold-forged and stress-relieved fittings only) are recommended. The paper describes a case in which fittings were welded in place in wet sour service flow lines and gas-oil separating plants which were ready to start. The failure of a welded fitting shortly after start-up led to extensive field hardness testing on all fittings from this manufacturer.

  10. Vortex flow in the technology of radiation wave cracking (RWC)

    E-Print Network [OSTI]

    L. A. Tsoy; V. N. Kolushov; A. G. Komarov; A. N. Tsoy

    2012-09-16T23:59:59.000Z

    This article examines the theory of vortex flows in relation to the processes occurring in the radiation-wave cracking of crude oil, when the crude oil is sprayed into the gas stream in the form of a mist and then is fed into the reactor, where it is treated by the accelerated electrons and the UHF radiation. The output of this process are the products with the specified parameters (high-octane petroleum products). This process operates at the ambient pressure and temperature, which makes the process safer for industrial purposes. Besides the process itself, the authors described the equipment used in this process, as well as the parameters of the optimal process.

  11. Fluid Mixing from Viscous Fingering

    E-Print Network [OSTI]

    Jha, Birendra

    Mixing efficiency at low Reynolds numbers can be enhanced by exploiting hydrodynamic instabilities that induce heterogeneity and disorder in the flow. The unstable displacement of fluids with different viscosities, or ...

  12. Bio-inspired fluid locomotion

    E-Print Network [OSTI]

    Chan, Brian, 1980-

    2009-01-01T23:59:59.000Z

    We have developed several novel methods of locomotion at low Reynolds number, for both Newtonian and non-Newtonian fluids: Robosnails 1 and 2, which operate on a lubrication layer, and the three-link swimmer which moves ...

  13. Rip Cosmology via Inhomogeneous Fluid

    E-Print Network [OSTI]

    V. V. Obukhov; A. V. Timoshkin; E. V Savushkin

    2013-09-18T23:59:59.000Z

    The conditions for the appearance of the Little Rip, Pseudo Rip and Quasi Rip universes in the terms of the parameters in the equation of state of some dark fluid are investigated. Several examples of the Rip cosmologies are investigated.

  14. Graduate Studies Environmental Fluid Mechanics

    E-Print Network [OSTI]

    Jacobs, Laurence J.

    and bridge scour · Wastewater dispersion in coastal waters · Cohesive sediment resuspension · Flood, and modeling research; and develop new technologies and tools that benefit engineering practice in fluid · Atmospheric, surface, and subsurface models · Flood/drought forecasting and management · Decision support

  15. DWPF CATALYTIC HYDROGEN GENERATION PROGRAM - REVIEW OF CURRENT STATUS

    SciTech Connect (OSTI)

    Koopman, D.

    2009-07-10T23:59:59.000Z

    Significant progress has been made in the past two years in improving the understanding of acid consumption and catalytic hydrogen generation during the Defense Waste Processing Facility (DWPF) processing of waste sludges in the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME). This report reviews issues listed in prior internal reviews, describes progress with respect to the recommendations made by the December 2006 external review panel, and presents a summary of the current understanding of catalytic hydrogen generation in the DWPF Chemical Process Cell (CPC). Noble metals, such as Pd, Rh, and Ru, are historically known catalysts for the conversion of formic acid into hydrogen and carbon dioxide. Rh, Ru, and Pd are present in the DWPF SRAT feed as by-products of thermal neutron fission of {sup 235}U in the original waste. Rhodium appears to become most active for hydrogen as the nitrite ion concentration becomes low (within a factor of ten of the Rh concentration). Prior to hydrogen generation, Rh is definitely active for nitrite destruction to N{sub 2}O and potentially active for nitrite to NO formation. These reactions are all consistent with the presence of a nitro-Rh complex catalyst, although definite proof for the existence of this complex during Savannah River Site (SRS) waste processing does not exist. Ruthenium does not appear to become active for hydrogen generation until nitrite destruction is nearly complete (perhaps less nitrite than Ru in the system). Catalytic activity of Ru during nitrite destruction is significantly lower than that of either Rh or Pd. Ru appears to start activating as Rh is deactivating from its maximum catalytic activity for hydrogen generation. The slow activation of the Ru, as inferred from the slow rate of increase in hydrogen generation that occurs after initiation, may imply that some species (perhaps Ru itself) has some bound nitrite on it. Ru, rather than Rh, is primarily responsible for the hydrogen generation in the SME cycle when the hydrogen levels are high enough to be noteworthy. Mercury has a role in catalytic hydrogen generation. Two potentially distinct roles have been identified. The most dramatic effect of Hg on hydrogen generation occurs between runs with and without any Hg. When a small amount of Hg is present, it has a major inhibiting effect on Rh-catalyzed H{sub 2} generation. The Rh-Ru-Hg matrix study showed that increasing mercury from 0.5 to 2.5 wt% in the SRAT receipt total solids did not improve the inhibiting effect significantly. The next most readily identified role for Hg is the impact it has on accelerating NO production from nitrite ion. This reaction shifts the time that the ideal concentration of nitrite relative to Rh occurs, and consequently causes the most active nitro-Rh species to form sooner. The potential consequences of this shift in timing are expected to be a function of other factors such as amount of excess acid, Rh concentration, etc. Graphical data from the Rh-Ru-Hg study suggested that Hg might also be responsible for partially inhibiting Ru-catalysis initially, but that the inhibition was not sustained through the SRAT and SME cycles. Continued processing led to a subsequent increase in hydrogen generation that was often abrupt and that frequently more than doubled the hydrogen generation rate. This phenomenon may have been a function of the extent of Hg stripping versus the initial Ru concentration in these tests. Palladium is an active catalyst, and activates during (or prior to) nitrite destruction to promote N{sub 2}O formation followed by a very small amount of hydrogen. Pd then appears to deactivate. Data to date indicate that Pd should not be a species of primary concern relative to Rh and Ru for hydrogen generation. Pd was a very mild catalyst for hydrogen generation compared to Rh and Ru in the simulated waste system. Pd was comparable to Rh in enhancing N{sub 2}O production when present at equal concentration. Pd, however, is almost always present at less than a quarter of the Rh concentration in S

  16. Concrete cover cracking with reinforcement corrosion of RC beam during chloride-induced corrosion process

    SciTech Connect (OSTI)

    Zhang Ruijin, E-mail: rjzhang@mail.neu.edu.c [Modern Design and Analysis Research Institute, Northeastern University, Shenyang (China); Castel, Arnaud; Francois, Raoul [LMDC - Laboratoire Materiaux et Durabilite des Constructions, Universite de Toulouse, UPS, INSA, Toulouse (France)

    2010-03-15T23:59:59.000Z

    This paper deals with the evolution of the corrosion pattern based on two beams corroded by 14 years (beam B1CL1) and 23 years (beam B2CL1) of conservation in a chloride environment. The experimental results indicate that, at the cracking initiation stage and the first stage of cracking propagation, localized corrosion due to chloride ingress is the predominant corrosion pattern and pitting corrosion is the main factor that influences the cracking process. As corrosion cracking increases, general corrosion develops rapidly and gradually becomes predominant in the second stage of cracking propagation. A comparison between existing models and experimental results illustrates that, although Vidal et al.'s model can better predict the reinforcement corrosion of beam B1CL1 under localized corrosion, it cannot predict the corrosion of beam B2CL1 under general corrosion. Also, Rodriguez's model, derived from the general corrosion due to electrically accelerated corrosion experiments, cannot match natural chloride corrosion irrespective of whether corrosion is localized or general. Thus, for natural general corrosion in the second stage of cracking propagation, a new model based on the parameter of average steel cross-section loss is put forward to predict steel corrosion from corrosion cracking.

  17. Threshold velocity for environmentally-assisted cracking in low alloy steels

    SciTech Connect (OSTI)

    Wire, G.L.; Kandra, J.T.

    1997-04-01T23:59:59.000Z

    Environmentally Assisted Cracking (EAC) in low alloy steels is generally believed to be activated by dissolution of MnS inclusions at the crack tip in high temperature LWR environments. EAC is the increase of fatigue crack growth rate of up to 40 to 100 times the rate in air that occurs in high temperature LWR environments. A steady state theory developed by Combrade, suggested that EAC will initiate only above a critical crack velocity and cease below this same velocity. A range of about twenty in critical crack tip velocities was invoked by Combrade, et al., to describe data available at that time. This range was attributed to exposure of additional sulfides above and below the crack plane. However, direct measurements of exposed sulfide densities on cracked specimens were performed herein and the results rule out significant additional sulfide exposure as a plausible explanation. Alternatively, it is proposed herein that localized EAC starting at large sulfide clusters reduces the calculated threshold velocity from the value predicted for a uniform distribution of sulfides. Calculations are compared with experimental results where the threshold velocity has been measured, and the predicted wide range of threshold values for steels of similar sulfur content but varying sulfide morphology is observed. The threshold velocity decreases with the increasing maximum sulfide particle size, qualitatively consistent with the theory. The calculation provides a basis for a conservative minimum velocity threshold tied directly to the steel sulfur level, in cases where no details of sulfide distribution are known.

  18. Fatigue cracking of a bare steel first wall in an inertial confinement fusion chamber

    SciTech Connect (OSTI)

    Hunt, R. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Abbott, R. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Havstad, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dunne, A. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-06-01T23:59:59.000Z

    Inertial confinement fusion power plants will deposit high energy X-rays onto the outer surfaces of the first wall many times a second for the lifetime of the plant. These X-rays create brief temperature spikes in the first few microns of the wall, which cause an associated highly compressive stress response on the surface of the material. The periodicity of this stress pulse is a concern due to the possibility of fatigue cracking of the wall. We have used finite element analyses to simulate the conditions present on the first wall in order to evaluate the driving force of crack propagation on fusion-facing surface cracks. Analysis results indicate that the X-ray induced plastic compressive stress creates a region of residual tension on the surface between pulses. This tension film will likely result in surface cracking upon repeated cycling. Additionally, the compressive pulse may induce plasticity ahead of the crack tip, leaving residual tension in its wake. However, the stress amplitude decreases dramatically for depths greater than 80–100 ?m into the fusion-facing surface. Crack propagation models as well as stress-life estimates agree that even though small cracks may form on the surface of the wall, they are unlikely to propagate further than 100 ?m without assistance from creep or grain erosion phenomena.

  19. Characterizing the cracking behavior of hard alpha defects in rotor grade Ti-6-4 alloy

    SciTech Connect (OSTI)

    McKeighan, P.C.; Perocchi, L.C.; Nicholls, A.E.; McClung, R.C.

    1999-07-01T23:59:59.000Z

    A program sponsored by the FAA is currently underway to develop predictive tools utilizing state-of-the-art damage tolerance and probabilistic methodologies that can be used in the life management of high energy rotors. The program is focusing on fatigue crack nucleation and growth from anomalies in titanium alloys known as hard alpha, an inclusion-like feature that can occur during the melting process. In the work detailed in this paper, two sizes of synthetic hard alpha defects are created in Ti-6Al-4V and subjected to static and fatigue loading. In addition, two different geometry anomalies are considered: one intersecting the surface of the specimen and another embedded internally. A number of crack detection transducers are used and shown to compare well to results from visual inspections on the surface defect specimens. These surface specimens tend to exhibit defect cracking at relatively low stress levels, typically on the order of 5--10 ksi. Although it appeared from the crack detection transducer that little or no cracking occurred in the interior anomaly specimens given an applied static stress of 100 ksi, subsequent metallographic sectioning demonstrated more extensive cracking and damage. The observed cracking behavior indicates that the diffusion zone may play an important role in the structural integrity of the hard alpha anomalies.

  20. Conditions under which cracks occur in modified 13% chromium steel in wet hydrogen sulfide environments

    SciTech Connect (OSTI)

    Hara, T.; Asahi, H.

    2000-05-01T23:59:59.000Z

    Occurrence of cracks in an API 13% Cr steel, modified 13% Cr steel, and duplex stainless steel were compared in various wet, mild hydrogen sulfide (H{sub 2}S) environments. The conditions under which cracks occurred in the modified 13% Cr steel in oil and gas production environments were made clear. No cracks occurred if pH > depassivation pH (pH{sub d}) and redox potential of sulfur (E{sub S(red/ax)}) < pitting potential (V{sub c}). Hydrogen embrittlement-type cracks occurred in pH > Ph{sub d} and E{sub S(red/ax)} > V{sub c}. The pH inside the pit decreased drastically and hydrogen embrittlement occurred. Cracks of the hydrogen embrittlement type occurred if pH < pH{sub d} and threshold hydrogen concentration under which cracks occur (H{sub th}) < hydrogen concentration in steel (H{sub 0}). No cracks occurred if pH < pH{sub d} and H{sub th} > H{sub 0}.