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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Sintered reaction bonded Si3N4 for the AGT 101 turbine rotor

The sintered reaction reaction bonded Si3N4 (SRBSN) process, with Y2O3 as a sintering aid, was selected for the fabrication of the AGT 101 turbine rotor. Experiments to determine the optimum Y2O3 composition of this system are discussed. The room temperature strength of the optimum material (RM-1) exceeds 700 MPa while the 1200 C strength exceeds 550 MPa. The slip casting fabrication technique employed for the AGT 101 simulated rotor is described. Rotors have been cast, nitrided and sintered. Densities exceeding 97% of theoretical (3.26 g/cc) have been obtained. Problems relating to sintering reproducibility, and the overall quality of the simulated rotors have been identified.

Mangels, J. A.↗
NASA NTRS1982

Advanced Gas Turbine (AGT) powertrain system development for automotive applications

Topics covered include the AGT 101 engine test; compressor design modification; cold air turbine testing; Mod 1 alloy turbine rotor fabrication; combustion aspects; regenerator development; and thermal screening tests for ceramic materials. The foil gas bearings, rotor dynamics, and AGT controls and accessories are also considered.

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NASA NTRS1985

Advanced Gas Turbine (AGT) technology report

Engine testing, ceramic component fabrication and evaluation, component performance rig testing, and producibility experiments at Pontiac comprised AGT 100 activities of this period, January to December 1984. Two experimental engines were available and allowed the evaluation of eight experimental assemblies. Operating time accumulated was 115 hr of burning and 156 hr total. Total cumulative engine operating time is now 225 hr. Build number 11 and 12 of engine S/N 1 totaled 28 burning hours and constituted a single assembly of the engine core--the compressor, both turbines, and the gearbox. Build number 11 of engine S/N 1 included a 1:07 hr continuous test at 100% gasifier speed (86,000 rpm). Build number 8 of engine S/N 2 was the first engine test with a ceramic turbine rotor. A mechanical loss test of an engine assembly revealed the actual losses to be near the original design allowance. Component development activity included rig testing of the compressor, combustor, and regenerator. Compressor testing was initiated on a rig modified to control the transfer of heat between flow path, lubricating oil, and structure. Results show successful thermal decoupling of the rig and lubricating/cooling oil. Rig evaluation of a reduced-friction compressor was initiated. Combustor testing covered qualification of ceramic parts for engine use, mapping of operating range limits, and evaluation of a relocated igniter plug. Several seal refinements were tested on the hot regenerator rig. An alternate regenerator disk, extruded MAS, was examined and found to be currently inadequate for the AGT 100 application. Also, a new technique for measuring leakage was explored on the regenerator rig. Ceramic component activity has focused on the development of state-of-the-art material strength characteristics in full-scale hardware. Injection-molded sintered alpha-SiC rotors were produced at Carborundum in an extensive process and tool optimization study.

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NASA NTRS1987

Advanced Gas Turbine (AGT) Technology Development Project, ceramic component developments

The ceramic component technology development activity conducted by Standard Oil Engineered Materials Company while performing as a principal subcontractor to the Garrett Auxiliary Power Division for the Advanced Gas Turbine (AGT) Technology Development Project (NASA Contract DEN3-167) is summarized. The report covers the period October 1979 through July 1987, and includes information concerning ceramic technology work categorized as common and unique. The former pertains to ceramic development applicable to two parallel AGT projects established by NASA contracts DEN3-168 (AGT100) and DEN3-167 (AGT101), whereas the unique work solely pertains to Garrett directed activity under the latter contract. The AGT101 Technology Development Project is sponsored by DOE and administered by NASA-Lewis. Standard Oil directed its efforts toward the development of ceramic materials in the silicon-carbide family. Various shape forming and fabrication methods, and nondestructive evaluation techniques were explored to produce the static structural components for the ceramic engine. This permitted engine testing to proceed without program slippage.

Teneyck, M. O.↗
NASA NTRS1987

Advanced Gas Turbine (AGT) technology development project

This report is the final in a series of Technical Summary Reports for the Advanced Gas Turbine (AGT) Technology Development Project, authorizrd under NASA Contract DEN3-167 and sponsored by the DOE. The project was administered by NASA-Lewis Research Center of Cleveland, Ohio. Plans and progress are summarized for the period October 1979 through June 1987. This program aims to provide the US automotive industry the high risk, long range technology necessary to produce gas turbine engines for automobiles that will reduce fuel consumption and reduce environmental impact. The intent is that this technology will reach the marketplace by the 1990s. The Garrett/Ford automotive AGT was designated AGT101. The AGT101 is a 74.5 kW (100 shp) engine, capable of speeds to 100,000 rpm, and operates at turbine inlet temperatures to 1370 C (2500 F) with a specific fuel consumption level of 0.18 kg/kW-hr (0.3 lbs/hp-hr) over most of the operating range. This final report summarizes the powertrain design, power section development and component/ceramic technology development.

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NASA NTRS1988

AGT (Advanced Gas Turbine) technology project

An overall summary documentation is provided for the Advanced Gas Turbine Technology Project conducted by the Allison Gas Turbine Division of General Motors. This advanced, high risk work was initiated in October 1979 under charter from the U.S. Congress to promote an engine for transportation that would provide an alternate to reciprocating spark ignition (SI) engines for the U.S. automotive industry and simultaneously establish the feasibility of advanced ceramic materials for hot section components to be used in an automotive gas turbine. As this program evolved, dictates of available funding, Government charter, and technical developments caused program emphases to focus on the development and demonstration of the ceramic turbine hot section and away from the development of engine and powertrain technologies and subsequent vehicular demonstrations. Program technical performance concluded in June 1987. The AGT 100 program successfully achieved project objectives with significant technology advances. Specific AGT 100 program achievements are: (1) Ceramic component feasibility for use in gas turbine engines has been demonstrated; (2) A new, 100 hp engine was designed, fabricated, and tested for 572 hour at operating temperatures to 2200 F, uncooled; (3) Statistical design methodology has been applied and correlated to experimental data acquired from over 5500 hour of rig and engine testing; (4) Ceramic component processing capability has progressed from a rudimentary level able to fabricate simple parts to a sophisticated level able to provide complex geometries such as rotors and scrolls; (5) Required improvements for monolithic and composite ceramic gas turbine components to meet automotive reliability, performance, and cost goals have been identified; (6) The combustor design demonstrated lower emissions than 1986 Federal Standards on methanol, JP-5, and diesel fuel. Thus, the potential for meeting emission standards and multifuel capability has been initiated; (7) Small turbine engine aerodynamic and mechanical design capability has been initiated; and (8) An infrastructure of manpower, facilities, materials, and fabrication capabilities has been established which is available for continued development of ceramic component technology in gas turbine and other heat engines.

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DOE OSTI2020

Materials Data on AgTe by Materials Project

AgTe crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to three Ag1+ and four Te1- atoms. There are a spread of Ag–Ag bond distances ranging from 3.01–3.09 Å. There are a spread of Ag–Te bond distances ranging from 2.83–3.14 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to two equivalent Ag1+ and four Te1- atoms. There are a spread of Ag–Te bond distances ranging from 2.83–3.23 Å. In the third Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to two equivalent Ag1+ and four Te1- atoms. There are a spread of Ag–Te bond distances ranging from 2.87–2.98 Å. There are three inequivalent Te1- sites. In the first Te1- site, Te1- is bonded in a 5-coordinate geometry to four Ag1+ and one Te1- atom. The Te–Te bond length is 2.90 Å. In the second Te1- site, Te1- is bonded in a 1-coordinate geometry to one Ag1+ and two equivalent Te1- atoms. In the third Te1- site, Te1- is bonded in a 7-coordinate geometry to seven Ag1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Er7(AgTe)2 by Materials Project

Er7(AgTe)2 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are four inequivalent Er sites. In the first Er site, Er is bonded in a 4-coordinate geometry to two equivalent Ag and two equivalent Te atoms. Both Er–Ag bond lengths are 3.01 Å. Both Er–Te bond lengths are 3.10 Å. In the second Er site, Er is bonded in a 3-coordinate geometry to three Te atoms. There are two shorter (3.24 Å) and one longer (3.28 Å) Er–Te bond lengths. In the third Er site, Er is bonded to two equivalent Ag and three Te atoms to form a mixture of distorted edge, corner, and face-sharing ErAg2Te3 trigonal bipyramids. Both Er–Ag bond lengths are 2.97 Å. There are one shorter (3.08 Å) and two longer (3.15 Å) Er–Te bond lengths. In the fourth Er site, Er is bonded in a 4-coordinate geometry to three equivalent Ag and one Te atom. There are two shorter (2.91 Å) and one longer (3.18 Å) Er–Ag bond lengths. The Er–Te bond length is 3.13 Å. Ag is bonded in a 7-coordinate geometry to seven Er atoms. There are two inequivalent Te sites. In the first Te site, Te is bonded in a 8-coordinate geometry to eight Er atoms. In the second Te site, Te is bonded to seven Er atoms to form distorted edge-sharing TeEr7 pentagonal bipyramids.

36 MATERIALS SCIENCE↗
NASA NTRS1982

AGT 100 automotive gas turbine system development

General Motors is developing an automotive gas turbine system that can be an alternate powerplant for future automobiles. Work sponsored by DOE and administered by NASA Lewis Research Center is emphasizing small component aerodynamics and high-temperature structural ceramics. Reliability requirements of the AGT 100 turbine system include chemical and structural ceramic component stability in the gas turbine environment. The power train system, its configuration and schedule are presented, and its performance tested. The aerodynamic component development is reviewed with discussions on the compressor, turbine, regenerator, interturbine duct and scroll, and combustor. Ceramic component development is also reviewed, and production cost and required capital investment are taken into consideration.

Helms, H. E. G.↗
NASA NTRS1981

Advanced Gas Turbine (AGT) powertrain system development for automotive applications

An automotive gas turbine powertrain system which, when installed in a 1985 production vehicle (3000 pounds inertia weight), is being developed with a CFDC fuel economy of 42.8 miles per gallon based on Environmental Protection Agency (EPA) test procedures and diesel No. 2 fuel. The AGT-powered vehicle shall give substantially the same overall vehicle driveability and performance as a comparable 1985 production vehicle powered by a conventional spark ignition powertrain system (baseline system). Gaseous emissions and particulate levels less than: NOx = 0.4 gm/mile, HC = 0.41 gm/mile, and CO = 3.4 gm/mile, and a total particulate of 0.2 gm/mile, using the same fuel as used for fuel economy measurements is expected, along with the ability to use a variety of alternate fuels.

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NASA NTRS1982

Advanced Gas Turbine (AGT) powertrain system development for automotive applications

A gas turbine powertrain for automobiles with reduced fuel consumption and reduced environmental impact is investigated. The automotive gas turbine, when installed in an automobile (3000 pounds inertia weight), provides a CFDC fuel economy of 42.8 miles per gallon based on EPA test procedures and diesel No. 2 fuel. The AGT powered vehicle substantially gives the same overall vehicle driveability and performance as a comparable production vehicle powered by a conventional spark ignition powertrain system. The emissions are less than federal standards, and a variety of fuels can be used.

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NASA NTRS1983

Component qualification and initial build of the AGT 100 advanced automotive gas turbine

In advance of initial dynamometer testing of the AGT 100 engine, all prime components and subsystems were bench/rig tested. Included were compressor, combustor, turbines, regenerator, ceramic components, and electronic control system. Results are briefly reviewed. Initial engine buildup was completed and rolled-out for test cell installation in July 1982. Shakedown testing included motoring and sequential firing of the combustor's three fuel nozzles.

Johnson, R. A.↗
NASA NTRS1984

Advanced Gas Turbine (AGT) powertrain system development for automotive applications report

This report describes progress and work performed during January through June 1984 to develop technology for an Advanced Gas Turbine (AGT) engine for automotive applications. Work performed during the first eight periods initiated design and analysis, ceramic development, component testing, and test bed evaluation. Project effort conducted under this contract is part of the DOE Gas Turbine Highway Vehicle System Program. This program is oriented at providing the United States automotive industry the high-risk long-range techology necessary to produce gas turbine engines for automobiles with reduced fuel consumption and reduced environmental impact. Technology resulting from this program is intended to reach the marketplace by the early 1990s.

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NASA NTRS1986

Advanced Gas Turbine (AGT) Technology Development Project annual report

This report is the tenth in a series of Technical Summary reports for the Advanced Gas Turbine (AGT) Technology Development Project, authorized under NASA Contract DEN3-167, and sponsored by the Department of Energy (DOE). This report was prepared by Garrett Turbine Engine Company, A Division of the Garrett Corporation, and includes information provided by Ford Motor Company, the Carborundum Company, and AiResearch Casting Company. The Project is administered by Mr. Thomas N. Strom, Project Manager, NASA-Lewis Research Center, Cleveland, Ohio. This report covers plans and progress for the period July 1, 1984 through June 30, 1985.

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NASA NTRS1986

Advanced Gas Turbine (AGT) Technology Project

Engine testing, ceramic component fabrication and evaluation, component performance rig testing, and analytical studies comprised AGT 100 activities during the 1985 year. Ten experimental assemblies (builds) were evaluated using two engines. Accrued operating time was 120 hr of burning and 170 hr total, bringing cumulative total operating time to 395 hr, all devoid of major failures. Tests identified the generator seals as the primary working fluid leakage sources. Power transfer clutch operation was demonstrated. An alpha SiC gasifier rotor engine test resulted in blade tip failures. Recurring case vibration and shaft whip have limited gasifier shaft speeds to 84%. Ceramic components successfully engine tested now include the SiC scroll assembly, Si3N3 turbine rotor, combustor assembly, regenerator disk bulkhead, turbine vanes, piston rings, and couplings. A compressor shroud design change to reduce heat recirculation back to the inlet was executed. Ceramic components activity continues to focus on the development of state-of-the-art material strength characteristics in full-scale engine hardware. Fiber reinforced glass-ceramic composite turbine (inner) backplates were fabricated by Corning Glass Works. The BMAS/III material performed well in engine testing. Backplates of MAS material have not been engine tested.

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NASA NTRS1987

Advanced Gas Turbine (AGT) Technology Development Project

This report is the eleventh in the series of Technical Summary reports for the Advanced Gas Turbine (AGT) Technology Development Project, authorized under NASA Contract DEN3-167, and sponsored by the Department of Energy (DOE). This report was prepared by Garrett Turbine Engine Company, A Division of the Garrett Corporation, and includes information provided by Ford Motor Company, the Standard Oil Company, and AiResearch Casting Company. This report covers plans and progress for the period July 1, 1985 through June 30, 1986. Technical progress during the reported period was highlighted by the 85-hour endurance run of an all-ceramic engine operating in the 2000 to 2250 F temperature regime. Component development continued in the areas of the combustion/fuel injection system, regenerator and seals system, and ceramic turbine rotor attachment design. Component rig testing saw further refinements. Ceramic materials showed continued improvements in required properties for gas turbine applications; however, continued development is needed before performance and reliability goals can be set.

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DOE OSTI2020

Materials Data on Ba(AgTe)2 by Materials Project

BaAg2Te2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba2+ is bonded in a 7-coordinate geometry to seven Te2- atoms. There are a spread of Ba–Te bond distances ranging from 3.50–3.78 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two equivalent Ag1+ and four Te2- atoms. Both Ag–Ag bond lengths are 2.94 Å. There are a spread of Ag–Te bond distances ranging from 2.87–2.95 Å. In the second Ag1+ site, Ag1+ is bonded to four Te2- atoms to form a mixture of corner and edge-sharing AgTe4 tetrahedra. There are a spread of Ag–Te bond distances ranging from 2.82–2.96 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to three equivalent Ba2+ and four Ag1+ atoms to form a mixture of distorted corner and edge-sharing TeBa3Ag4 pentagonal bipyramids. In the second Te2- site, Te2- is bonded in a 8-coordinate geometry to four equivalent Ba2+ and four Ag1+ atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1981

AGT-102 automotive gas turbine

Development of a gas turbine powertrain with a 30% fuel economy improvement over a comparable S1 reciprocating engine, operation within 0.41 HC, 3.4 CO, and 0.40 NOx grams per mile emissions levels, and ability to use a variety of alternate fuels is summarized. The powertrain concept consists of a single-shaft engine with a ceramic inner shell for containment of hot gasses and support of twin regenerators. It uses a fixed-geometry, lean, premixed, prevaporized combustor, and a ceramic radial turbine rotor supported by an air-lubricated journal bearing. The engine is coupled to the vehicle through a widerange continuously variable transmission, which utilizes gearing and a variable-ratio metal compression belt. A response assist flywheel is used to achieve acceptable levels of engine response. The package offers a 100 lb weight advantage in a Chrysler K Car front-wheel-drive installation. Initial layout studies, preliminary transient thermal analysis, ceramic inner housing structural analysis, and detailed performance analysis were carried out for the basic engine.

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