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Physics of antimatter-matter reactions for interstellar propulsion

Description: At the stage of the antiproton-nucleon annihilation chain of events relevant to propulsion the annihilation produces energetic charged pions and gamma rays. If annihilation occurs in a complex nucleus, protons, neutrons, and other nuclear fragments are also produced. The charge, number, and energy of the annihilation products are such that annihilation rocket engine concepts involving relatively low specific impulse (I/sub sp/ approx. = 1000 to 2000 s) and very high I/sub sp/ (3 x 10/sup 7/ s) … more
Date: August 22, 1986
Creator: Morgan, D.L. Jr.
Partner: UNT Libraries Government Documents Department
open access

Design of a diesel exhaust-gas purification system for inert-gas drilling

Description: To combat the serious oxygen corrosion of drill pipe when a low density drilling fluid (air or mist) is used in geothermal drilling, a system has been designed that produces an inert gas (essentially nitrogen) to be substituted for air. The system fits on three flatbed trailers, is roadable and produces 2000 scfm of gas. The projected cost for gas is slightly less than $2.00 per thousand standard cubic feet.
Date: January 1, 1982
Creator: Caskey, B. C.
Partner: UNT Libraries Government Documents Department
open access

Detection sensitivity of x-ray CT imaging for NDE of green-state ceramics

Description: Improved ceramic-processing methods that use pressure slip-casting and injection molding are being developed at Norton Advanced Ceramics, with a goal of producing reliable structural ceramics for advanced heat engines. Nondestructive evaluation (NDE) of ceramic parts at different stages of processing can provide useful diagnostic information to help improve processing techniques. For example, an evaluation of density gradients in as-cast green-body samples can be used to judge mold performance … more
Date: 1991~
Creator: Gopalsami, N.; Rizo, P.; Ellingson, W. A. & Tracey, D. M.
Partner: UNT Libraries Government Documents Department
open access

Inherently safe nuclear-driven internal combustion engines

Description: A family of nuclear driven engines is described in which nuclear energy released by fissioning of uranium or plutonium in a prompt critical assembly is used to heat a working gas. Engine performance is modeled using a code that calculates hydrodynamics, fission energy production, and neutron transport self-consistently. Results are given demonstrating a large negative temperature coefficient that produces self-shutoff of energy production. Reduced fission product inventory and the self-shutoff … more
Date: June 14, 1991
Creator: Alesso, P.; Chow, Tze-Show; Condit, R.; Heidrich, J.; Pettibone, J. & Streit, R.
Partner: UNT Libraries Government Documents Department
open access

Operating experience with a liquid-hydrogen fueled Buick and refueling system

Description: An investigation of liquid-hydrogen storage and refueling systems for vehicular applications was made in a recently completed project. The vehicle used in the project was a 1979 Buick Century sedan with a 3.8-L displacement turbocharged V6 engine and an automatic transmission. The vehicle had a fuel economy for driving in the high altitude Los Alamos area that was equivalent to 2.4 km/L of liquid hydrogen or 8.9 km/L of gasoline on an equivalent energy basis. About 22% less energy was required … more
Date: January 1, 1982
Creator: Stewart, W.F.
Partner: UNT Libraries Government Documents Department
open access

Advanced nuclear rocket engine mission analysis

Description: The use of a derivative of the NERVA engine developed from 1955 to 1973 was evluated for potential application to Air Force orbital transfer and maneuvering missions in the time period 1995 to 2020. The NERVA stge was found to have lower life cycle costs (LCC) than an advanced chemical stage for performing low earth orbit (LEO) to geosynchronous orbit (GEO0 missions at any level of activity greater than three missions per year. It had lower life cycle costs than a high performance nuclear elect… more
Date: December 1, 1987
Creator: Ramsthaler, J.; Farbman, G.; Sulmeisters, T.; Buden, D. & Harris, P.
Partner: UNT Libraries Government Documents Department
open access

Intrinsically irreversible heat engines

Description: The concept of an intrinsically irreversible heat engine is examined as a means of obtaining temperatures near absolute zero. These engines use the irreversible process of thermal conduction to achieve the necessary phasing between temperature changes and motion of a primary medium and therefore have only one moving mechanical element. (GHT)
Date: January 1, 1982
Creator: Wheatley, J.C.
Partner: UNT Libraries Government Documents Department
open access

Numerical simulation of reactive flow in internal combustion engines. [CONCHAS-SPRAY code]

Description: Multidimensional numerical simulations of the reactive fluid flow in an internal combustion engine cylinder are useful in helping engine designers obtain insight into the physical mechanisms governing efficiency and pollutant formation. A comprehensive numerical model for internal combustion engine cylinder simulations that has been developed at Los Alamos is described. The model is currently embodied in a two-dimensional (axisymmetric) computer code called CONCHAS-SPRAY. Work is in progress on… more
Date: January 1, 1980
Creator: Cloutman, L.D.; Dukowicz, J.K. & Ramshaw, J.D.
Partner: UNT Libraries Government Documents Department
open access

Nuclear thermal rocket clustering: 1, A summary of previous work and relevant issues

Description: A general review of the technical merits of nuclear thermal rocket clustering is presented. A summary of previous analyses performed during the Rover program is presented and used to assess clustering in the context of projected Space Exploration Initiative missions. A number of technical issues are discussed including cluster reliability, engine-out operation, neutronic coupling, shutdown core power generation, shutdown reactivity requirements, reactor kinetics, and radiation shielding. 7 refs… more
Date: July 14, 1991
Creator: Buksa, J.J. & Houts, M.G.
Partner: UNT Libraries Government Documents Department
open access

Four-wheel-drive powertrain models for real-time simulation

Description: Dynamic vehicle powertrain models have been formulated by many researchers for particular applications, mainly the analysis of powertrain characteristics or vibration. In this paper, we formulate models of four-wheel-drive vehicle powertrains for the purpose of real-time simulation. While not encompassing the complete characteristics of powertrain operation, these models are applicable for use in vehicle simulators, and include both the differential and lock-up modes of four-wheel-drive transfe… more
Date: January 1, 1991
Creator: Freeman, J.S. (Los Alamos National Lab., NM (United States)) & Velinsky, S.A. (California Univ., Davis, CA (United States). Dept. of Mechanical Engineering)
Partner: UNT Libraries Government Documents Department
open access

The turbulent heat flux in low Mach number flows with large density variations

Description: A transport equation has been derived which is the difference between the volume- and mass-averaged velocities and is simply related to the turbulent heat flux phi/sup h/. Using this equation and an assumption analogous to the drift flux approximation of two-phase flow modeling, an algebraic closure relation for phi/sup h/ that exhibits fluxes due to directed transport proportional to -del anti p and due to gradient transport proportional to -del Tau has been obtained. Much work remains to be d… more
Date: January 1, 1988
Creator: O'Rourke, P.J. & Collins, L.R.
Partner: UNT Libraries Government Documents Department
open access

Single cylinder spark ignition engine study of NO and NO/sub 2/ emissions for methanol, iso-octane and nitrogen doped methanol with emphasis on measurement technique

Description: NO and NO/sub 2/ emissions from a single cylinder CFR engine were measured as a function of fuel air equivalence ratio for the spark ignited combustion of methanol, iso-octane and nitrogen doped methanol. In all cases, no NO/sub 2/ was detected for fuel-rich or stoichiometric combustion, while significant amounts of NO/sub 2/ were found for fuel-lean combustion. The exhaust system and exhaust sampling system were throughly tested for NO and NO/sub 2/ conversions, NO/sub 2/ to NO conversions and… more
Date: January 1, 1977
Creator: Brateman, J.H. & Klemm, R.B.
Partner: UNT Libraries Government Documents Department
open access

C-CAMP, A closed cycle alkali metal power system

Description: A concept is presented for a Closed-Cycle Alkali Metal (C-CAMP) power systems which utilizes the heat of reaction of an alkali metal and halogen compound to vaporize an alkali metal turbine fluid for a Rankine cycle. Unique features of the concept are (1) direct contact (heat exchange) between the reaction products and turbine fluid, and (2) a flow-through chemical reactor/boiler. The principal feasibility issues of the concept relate to the degree of cross-mixing of product and turbine fluid s… more
Date: January 1, 1988
Creator: Wichner, R. P. & Hoffman, H. W.
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the workshop on the modification of the upper atmosphere by Satellite Power System (SPS) propulsion effluents

Description: Results of a workshop held in June 1979, to identify research needs for evaluating environmental impacts on the upper atmosphere (here defined as greater than 70 km) due to Satellite Power System (SPS) transport, i.e., propulsion and reentry are presented. The substantial injections of water and hydrogen therefrom may lead to global-scale regions of reduced ionization in the ionospheric F-Region that may have a serious impact on worldwide HF radio communications; and the resulting possibly sign… more
Date: June 1, 1980
Creator: Bauer, E.
Partner: UNT Libraries Government Documents Department
open access

Status of the Advanced Stirling Conversion System Project for 25 kW dish Stirling applications

Description: Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising heat engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting technology development for Stirling convertors directed toward a dynamic power s… more
Date: January 1, 1991
Creator: Shaltens, R.K. & Schreiber, J.G.
Partner: UNT Libraries Government Documents Department
open access

Proposed method for remote thermometry in turbine engines. [Eu-doped yttrium oxide]

Description: The method uses laser-induced fluorescence from a pulsed uv laser to excite a rare-earth-oxide phosphor bonded in a thin layer to the surface to be measured. The luminescent decay times of certain lines are temperature-dependent. Initial results indicate that at least one phosphor, europium-doped yttrium oxide, is usable to 950/sup 0/C. (DLC)
Date: January 1, 1985
Creator: Noel, B. W.; Cates, M. R.; Allison, S. W.; Borella, H. M.; Franks, L. A. & Marshall, B. R.
Partner: UNT Libraries Government Documents Department
open access

Advanced materials for alternative fuel capable directly fired heat engines

Description: The first conference on advanced materials for alternative fuel capable directly fired heat engines was held at the Maine Maritime Academy, Castine, Maine. It was sponsored by the US Department of Energy, (Assistant Secretary for Fossil Energy) and the Electric Power Research Institute, (Division of Fossil Fuel and Advanced Systems). Forty-four papers from the proceedings have been entered into EDB and ERA and one also into EAPA; three had been entered previously from other sources. The papers … more
Date: December 1, 1979
Creator: Fairbanks, J. W. & Stringer, J. (eds.)
Partner: UNT Libraries Government Documents Department
open access

Analytical modeling of line focus solar collectors

Description: Solar thermal electric power generation systems and industrial process heat systems generating steam through flash vaporization require a constant outlet temperature from the collector field. This constant temperature is most efficiently maintained by adjusting the circulating fluid flow rate. Successful design of analog controllers for this regulation requires knowledge of system dynamics and the nonlinear nature of the system parameters. Simplified models relating deviations in outlet tempera… more
Date: April 1, 1980
Creator: Wright, J. D.
Partner: UNT Libraries Government Documents Department
open access

Performance and emissions of a catalytic reactor with propane, diesel, and Jet A fuels

Description: As part of the ERDA-funded Gas Turbine Highway Vehicle Systems project, tests were made to determine the performance and emissions of a catalytic reactor operated with propane, No. 2 diesel, and Jet A fuels. A 12-cm diameter and 16-cm long catalytic reactor using a proprietary noble metal catalyst was operated at an inlet temperature of 800 K, a pressure of 3 x 10/sup 5/ Pa and reference velocities of 10 to 15 m/s. No significant differences between the performance of the three fuels were obser… more
Date: January 1, 1977
Creator: Anderson, D. N.
Partner: UNT Libraries Government Documents Department
open access

Assessment of the advantages and feasibility of a nuclear rocket

Description: The feasibility of rebuilding and testing a nuclear thermal rocket (NTR) for the Mars mission has been investigated. Calculations indicate that an NTR would substantially reduce the earth-orbit assembled mass compared to LOX/LH/sub 2/ systems. The mass savings were 36% and 65% for the cases of total aerobraking and of total propulsive braking respectively. Consequently, the cost savings for a single mission of using an NTR, if aerobraking is feasible, are probably insufficient to warrant the NT… more
Date: January 1, 1985
Creator: Howe, S.D.
Partner: UNT Libraries Government Documents Department
open access

Overview of the 1985 NASA Lewis Research Center SP-100 free-piston Stirling engine activities

Description: An overview of the 1985 (NASA) Lewis Research Center free-piston Stirling engine activities in support of the SP-100 Program is presented. The SP-100 program is being conducted in support of the Department of Advanced Research Projects Agency (DARPA) and the Department of Energy (DOE), and NASA. This effort is keyed on the design, fabrication, assembly, and testing of a 25 kW(e) Stirling space-power technology-feasibility demonstrator engine. Another facet of the SP-100 project covers the statu… more
Date: January 1, 1985
Creator: Slaby, J.G.
Partner: UNT Libraries Government Documents Department
open access

Performance of Digital Integrated Circuit Technologies at Very High Temperatures

Description: Results of investigations of the performance and reliability of digital bipolar and CMOS integrated circuits over the 25 to 340/sup 0/C range are reported. Included in these results are both parametric variation information and analysis of the functional failure mechanisms. Although most of the work was done using commercially available circuits (TTL and CMOS) and test chips from commercially compatible processes, some results of experimental simulations of dielectrically isolated CMOS are also… more
Date: January 1, 1980
Creator: Prince, J. L.; Draper, B. L.; Rapp, E. A.; Kromberg, J. N. & Fitch, L. T.
Partner: UNT Libraries Government Documents Department
open access

Overview of free-piston Stirling SP-100 activities at the NASA Lewis Research Center

Description: An overview of the National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) SP-100 free-piston Stirling engine activities is presented. These activities are being conducted in support of the Department of Defense (DOD), Department of Energy (DOE), and NASA. The space-power technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE). Another facet of the SP-100 project covers the status of an endurance test. Dynamic balancin… more
Date: January 1, 1986
Creator: Slaby, J.G.
Partner: UNT Libraries Government Documents Department
open access

Microcomputer analysis of regenerative heat exchangers for oscillating flow

Description: Regenerative heat exchangers for use in oscillating flows such as those occurring in Stirling engines present considerable analytical problems to the thermal engineer. A simplified finite element analysis has been implemented in a spreadsheet, providing improved access to analytical assumptions and allowing parametric analysis of current heat transfer data. In addition, an irreversibility analysis has been implemented using the thermal and friction results in the spreadsheet. It is suited for e… more
Date: March 1, 1987
Creator: Hutchinson, R. A. & Lyke, S. E.
Partner: UNT Libraries Government Documents Department
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