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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

Alkali metal/halide thermal energy storage systems performance evaluation

A pseudoheat-pipe heat transfer mechanism has been demonstrated effective in terms of both total heat removal efficiency and rate, on the one hand, and system isothermal characteristics, on the other, for solar thermal energy storage systems of the kind being contemplated for spacecraft. The selection of appropriate salt and alkali metal substances for the system renders it applicable to a wide temperature range. The rapid heat transfer rate obtainable makes possible the placing of the thermal energy storage system around the solar receiver canister, and the immersing of heat transfer fluid tubes in the phase change salt to obtain an isothermal heat source.

Phillips, W. M.↗
NASA NTRS1978

Performance and economics of advanced energy conversion systems for coal and coal-derived fuels

The desire to establish an efficient Energy Conversion System to utilize the fossil fuel of the future - coal - has produced many candidate systems. A comparative technical/economic evaluation was performed on the seven most attractive advanced energy conversion systems. The evaluation maintains a cycle-to-cycle consistency in both performance and economic projections. The technical information base can be employed to make program decisions regarding the most attractive concept. A reference steam power plant was analyzed to the same detail and, under the same ground rules, was used as a comparison base. The power plants were all designed to utilize coal or coal-derived fuels and were targeted to meet an environmental standard. The systems evaluated were two advanced steam systems, a potassium topping cycle, a closed cycle helium system, two open cycle gas turbine combined cycles, and an open cycle MHD system.

Corman, J. C.↗
NASA NTRS1977

A simulation model for wind energy storage systems. Volume 2: Operation manual

A comprehensive computer program (SIMWEST) developed for the modeling of wind energy/storage systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel, and pneumatic) is described. Features of the program include: a precompiler which generates computer models (in FORTRAN) of complex wind source/storage/application systems, from user specifications using the respective library components; a program which provides the techno-economic system analysis with the respective I/O the integration of system dynamics, and the iteration for conveyance of variables; and capability to evaluate economic feasibility as well as general performance of wind energy systems. The SIMWEST operation manual is presented and the usage of the SIMWEST program and the design of the library components are described. A number of example simulations intended to familiarize the user with the program's operation is given along with a listing of each SIMWEST library subroutine.

Warren, A. W.↗
NASA NTRS2013

Energy Harvesting Systems and Methods of Assembling Same

A method of assembling an energy harvesting system is provided. The method includes coupling at least one energy storage device in flow communication with at least one apparatus that is configured to generate thermal energy and to transfer the thermal energy into at least one fluid stream. The energy storage device is configured to store the fluid stream. Moreover, the method includes coupling at least one fluid transfer device downstream from the energy storage device. The fluid transfer device receives the fluid stream from the energy storage device. A bladeless turbine is coupled in flow communication with the fluid transfer device, wherein the bladeless turbine receives the fluid stream to generate power.

Cepeda-Rizo, Juan↗
NASA NTRS1983

Energy Recovery System

Cogeneration system is one in which the energy ordinarily wasted in an industrial process is recovered and reused to create a second form of energy. Such an energy recovery system is in use at Crane Company's plant in Ferguson, KY, which manufactures ceramic bathroom fixtures. Crane's system captures hot stack gases from the company's four ceramic kilns and uses them to produce electrical power for plant operations.

Source record↗
NASA NTRS1983

Efficient computerized model for dynamic analysis of energy conversion systems

In searching for the optimum parameters that minimize the total life cycle cost of an energy conversion system, various combinations of components are examined and the resulting system performance and associated economics are studied. The systems performance and economics simulation computer program (SPECS) was developed to fill this need. The program simulates the fluid flow, thermal, and electrical characteristics of a system of components on a quasi-steady state basis for a variety of energy conversion systems. A unique approach is used in which the set of characteristic equations is solved by the Newton-Raphson technique. This approach eliminates the tedious iterative loops which are found in comparable programs such as TRNSYS or SOLTES-1. Several efficient features were also incorporated such as the centralized control and energy management scheme, and analogous treatment of energy flow in electrical and mechanical components, and the modeling of components of similar fundamental characteristics using generic subroutines. Initial tests indicate that this model can be used effectively with a relatively small number of time steps and low computer cost.

Hughes, R. D.↗
NASA NTRS1976

Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 2: Advanced energy conversion systems. Part 1: Open-cycle gas turbines

Ten energy conversion systems are defined and analyzed in terms of efficiency. These include: open-cycle gas turbine recuperative; open-cycle gas turbine; closed-cycle gas turbine; supercritical CO2 cycle; advanced steam cycle; liquid metal topping cycle; open-cycle MHD; closed-cycle inert gas MHD; closed-cycle liquid metal MHD; and fuel cells. Results are presented.

Brown, D. H.↗
NASA NTRS1980

A study of the applicability/compatibility of inertial energy storage systems to future space missions

The applicability/compatibility of inertial energy storage systems like the homopolar generator (HPG) and the compensated pulsed alternator (CPA) to future space missions is explored. Areas of CPA and HPG design requiring development for space applications are identified. The manner in which acceptance parameters of the CPA and HPG scale with operating parameters of the machines are explored and the types of electrical loads which are compatible with the CPA and HPG are examined. Potential applications including the magnetoplasmadynamic (MPD) thruster, pulsed data transmission, laser ranging, welding and electromagnetic space launch are discussed.

Weldon, W. F.↗
NASA NTRS1982

Chemical and electrochemical behavior of the Cr(3)/Cr(2) half cell in the NASA Redox Energy Storage System

The Cr(III) complexes in the NASA Redox Energy Storage System were isolated and identified as Cr(H2O)6(+3) and Cr(H2O)5Cl(+2) by ion exchange chromatography and visible spectrophotometry. The cell reactions during charge-discharge cycles were followed by means of visible spectrophotometry. The spectral bands were resolved into component peaks and concentrations calculated using Beer's Law. During the charge mode Cr(H2O)5Cl(+2) is reduced to Cr(H2O)5Cl(+) and during the discharge mode Cr(H2O)5Cl(+) is oxidized back to Cr(H2O)5Cl(+2). Both electrode reactions occur via a chloride-bridge inner-sphere reaction pathway. Hysteresis effects can be explained by the slow attainment of equilibrium between Cr(H2O)6(+3) and Cr(H2O)5Cl(+2).

Johnson, D. A.↗
NASA NTRS2006

Integrated Thermal Energy Management System (ITEMS)

A viewgraph presentation describing the Integrated Thermal Energy Management System (ITEMS) is shown. The topics include: 1) The Benefits of Two-Phase Flow; 2) Description; and 3) Hardware.

thermal controls↗
NASA NTRS1997

Cold Weather Wind Turbines: A Joint NASA/NSF/DOE Effort in Technology Transfer and Commercialization

Renewable energy sources and their integration with other power sources to support remote communities is of interest for Mars applications as well as Earth communities. The National Science Foundation (NSF), NASA, and the Department of Energy (DOE) have been jointly supporting development of a 100 kW cold weather wind turbine through grants and SBIRs independently managed by each agency but coordinated by NASA. The NSF grant addressed issues associated with the South Pole application and a 3 kW direct drive unit is being tested there in anticipation of the 100 kW unit operation. The DOE-NREL contract focused on development of the 100 kW direct drive generator. The NASA SBIR focused on the development of the 100 kW direct drive wind turbine. The success of this effort has required coordination and team involvement of federal agencies and the industrial partners. Designs of the wind turbine and component performance testing results will be presented. Plans for field testing of wind turbines, based on this design, in village energy systems in Alaska and in energy production at the South Pole Station will be discussed. Also included will be a discussion of terrestrial and space use of hybrid energy systems, including renewable energy sources, such as the wind turbine, to support remote communities.

Flynn, Michael↗
NASA NTRS1979

Control strategy for a variable-speed wind energy conversion system

A control concept for a variable-speed wind energy conversion system is proposed, for which a self-exited asynchronous cage generator is used along with a system of thyristor converters. The control loops are the following: (1) regulation of the entrainment speed as function of available mechanical energy by acting on the resistance couple of the asynchronous generator; (2) control of electric power delivered to the asynchronous machine, functioning as a motor, for start-up of the vertical axis wind converter; and (3) limitation of the slip value, and by consequence, of the induction currents in the presence of sudden variations of input parameters.

Jacob, A.↗
NASA NTRS1980

Development of a thermal storage module using modified anhydrous sodium hydroxide

The laboratory scale testing of a modified anhydrous NaOH latent heat storage concept for small solar thermal power systems such as total energy systems utilizing organic Rankine systems is discussed. A diagnostic test on the thermal energy storage module and an investigation of alternative heat transfer fluids and heat exchange concepts are specifically addressed. A previously developed computer simulation model is modified to predict the performance of the module in a solar total energy system environment. In addition, the computer model is expanded to investigate parametrically the incorporation of a second heat exchange inside the module which will vaporize and superheat the Rankine cycle power fluid.

Rice, R. E.↗
NASA NTRS1980

Cost projections for Redox Energy storage systems

A preliminary design and system cost analysis was performed for the redox energy storage system. A conceptual design and cost estimate was prepared for each of two energy applications: (1) electric utility 100-MWh requirement (10-MW for ten hours) for energy storage for utility load leveling application, and (2) a 500-kWh requirement (10-kW for 50 hours) for use with a variety of residential or commercial applications, including stand alone solar photovoltaic systems. The conceptual designs were based on cell performance levels, system design parameters, and special material costs. These data were combined with estimated thermodynamic and hydraulic analysis to provide preliminary system designs. Results indicate that the redox cell stack to be amenable to mass production techniques with a relatively low material cost.

Michaels, K.↗
NASA NTRS1975

Considerations for performance evaluation of solar heating and cooling systems

One of the many factors which must be considered in performance evaluation of solar energy systems is the relative merit of a given solar energy system when compared to a standard conventional system. Although initial and operational costs will be dominant factors in the comparison of the two types of systems and will be given prime consideration in system selection, sufficient data are not yet available for a definitive treatment of these variables. It is possible, however, to formulate relationships between the nonsolar energy requirements of the solar energy systems and the energy requirements of a conventional system in terms of the primary performance parameters of the systems. Derivations of such relationships, some parametric data for selected ranges of the performance parameters, and data with respect to limiting conditions are presented.

Littles, J. W.↗