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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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Analysis of shadowing effects on spacecraft power systems
This paper describes the Orbiting Spacecraft Shadowing Analysis (OSSA) computer program that was developed at NASA Lewis Research Center in order to assess the shadowing effects on various power systems. The algorithms, inputs and outputs are discussed. Examples of typical shadowing analyses that have been performed for the International Space Station Freedom, International Space Station Alpha and the joint United States/Russian Mir Solar Dynamic Flight Experiment Project are covered. Effects of shadowing on power systems are demonstrated.
The effect of concentrator field layout on the EE-1 small community solar power system
The point-focusing distributed receiver (PFDR) concept is employed by a number of solar thermal power systems currently under development. One type of PFDR system which shows particular promise incorporates distributed energy generation. According to this concept each parabolic dish collector is a self-contained power generation module, and a conventional electrical system is used to interconnect the modules. The concept is thus modular, and any number of power modules can be combined to achieve the required plant size. Given the benefits of mass production, it appears that this type of system can produce electricity at lower cost than is projected for conventional (fossil) power systems over the next decade. An employment of organic Rankine cycle heat engines is considered.
A Generalized Power System Architecture Sizing and Analysis Framework
The aeronautics industry has been challenged to increase efficiency, reduce noise and emissions, and decrease dependency on carbon-based fuels. To address these needs, NASA has identified and begun to pursue electrified aircraft as a possible solution. The power system for an electric aircraft can exist in many different forms, however; at the early design stage the engineer(s) must identify whether a hybrid- or turbo- electric solution may be best, whether the power transmission system is to be AC or DC, and to ultimately answer the question: does the electric solution provide a net system benefit compared to the fully mechanical solution? This paper describes a generalized power system architecture sizing and analysis framework to provide a mechanism to answering these questions, along with an example based on the STARC-ABL Architecture.
Mariner Mars power system optimization study Final report
Optimum Mariner-class spacecraft electric power system providing improved utilization of solar array power and greater reliability
Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 3: Experimental System Descriptions
The design and development of a modular solar thermal power system for application in the 1 to 10 MWe range is described. The system consists of five subsystems: the collector, power conversion, energy transport, energy storage, and the plant control subsystem. The collector subsystem consists of concentrator, receiver, and tower assemblies. The energy transport subsystem uses a mixture of salts with a low melting temperature to transport thermal energy. A steam generator drives a steam Rankine cycle turbine which drives an electrical generator to produce electricity. Thermal and stress analysis tests are performed on each subsystem in order to determine the operational reliability, the minimum risk of failure, and the maintenance and repair characteristics.
High-Capacity Communications from Martian Distances Part 2: Spacecraft Antennas and Power Systems
This paper summarizes recent advances in antenna and power systems technology to enable a high data rate Ka-band Mars-to-Earth telecommunications system. Promising antenna technologies are lightweight, deployable space qualified structures at least 12-m in diameter (potentially up to 25-m). These technologies include deployable mesh reflectors, inflatable reflectarray and folded thermosetting composite. Advances in 1kW-class RF power amplifiers include both TWTA and SSPA technologies.
Balloon Fuel Cell Power System
NASA Lewis Research Center's Electrochemical Technology Branch has teamed with the NASA Wallops Flight Facility to demonstrate the operation of a hydrogen-oxygen proton exchange membrane (PEM) fuel cell for application in the upper atmosphere. NASA Wallops' Balloon Programs Branch has a requirement for a high-power, long-duration power system for use on a scientific balloon platform. The current power system will not meet these needs. The objective of this program is to deliver a 200-W (minimum) fuel cell system that can deliver approximately 10 kWh of electrical energy.
Dynamic characteristics of a 20 kHz resonant power system - Fault identification and fault recovery
A detailed simulation of a dc inductor resonant driver and receiver is used to demonstrate the transient characteristics of a 20 kHz resonant power system during fault and overload conditions. The simulated system consists of a dc inductor resonant inverter (driver), a 50-meter transmission cable, and a dc inductor resonant receiver load. Of particular interest are the driver and receiver performance during fault and overload conditions and on the recovery characteristics following removal of the fault. The information gained from these studies sets the stage for further work in fault identification and autonomous power system control.
Solar dynamic power system development for Space Station Freedom
The development of a solar dynamic electric power generation system as part of the Space Station Freedom Program is documented. The solar dynamic power system includes a solar concentrator, which collects sunlight; a receiver, which accepts and stores the concentrated solar energy and transfers this energy to a gas; a Brayton turbine, alternator, and compressor unit, which generates electric power; and a radiator, which rejects waste heat. Solar dynamic systems have greater efficiency and lower maintenance costs than photovoltaic systems and are being considered for future growth of Space Station Freedom. Solar dynamic development managed by the NASA Lewis Research Center from 1986 to Feb. 1991 is covered. It summarizes technology and hardware development, describes 'lessons learned', and, through an extensive bibliography, serves as a source list of documents that provide details of the design and analytic results achieved. It was prepared by the staff of the Solar Dynamic Power System Branch at the NASA Lewis Research Center in Cleveland, Ohio. The report includes results from the prime contractor as well as from in-house efforts, university grants, and other contracts. Also included are the writers' opinions on the best way to proceed technically and programmatically with solar dynamic efforts in the future, on the basis of their experiences in this program.
Brushless rotating electrical generators for space auxiliary power systems, volume 5
Brushless rotating electrical generators for space auxiliary power systems
Radioisotope Power Systems for In-situ Exploration of Titan and Venus
This viewgraph presentation reviews the timeline for the robotic in situ investigation of Titan and Venus, and the use of radioisotope power systems in this exploration. The atmospheric and surface conditions of both sites are reviewed. The presentation also examines the conceptual design of the Venus Mobile Explorer and the Titan orbiter and in situ explorer. After this the presentation reviews the radioisotope power systems for each of the vehicles, with some explanation of the different requirements based on the vastly different environments that they would be investigating
Computer program for thermodynamic performance of Brayton-cycle space-power systems
Computer program for calculating thermodynamic performance of Brayton cycle space power systems
Aperture Shield Materials Characterized and Selected for Solar Dynamic Space Power System
The aperture shield in a solar dynamic space power system is necessary to prevent thermal damage to the heat receiver should the concentrated solar radiation be accidentally or intentionally focused outside of the heat receiver aperture opening and onto the aperture shield itself. Characterization of the optical and thermal properties of candidate aperture shield materials was needed to support the joint U.S./Russian solar dynamic space power effort for Mir. The specific objective of testing performed at the NASA Lewis Research Center was to identify a high-temperature material with a low specular reflectance, a low solar absorptance, and a high spectral emittance so that during an off-pointing event, the amount of solar energy reflecting off the aperture shield would be small, the ratio of solar absorptance to spectral emittance would provide the lowest possible equilibrium temperature, and the integrity of the aperture shield would remain intact.
Design Study of a Solar Hydrogen Propulsion and Power System Quarterly Report, 17 May 1963 - 17 Aug. 1963
Component relationships for solar propulsion-power system - cryogenic storage, solar concentrator size, and thrust level
Continued development of a hypergolic electrical power system Final report, Apr. 1966 - Jan. 1967
Hypergolic turboalternator flight-type power system to complement lunar module electrical power supply
Performance of the electrically-heated 2 to 15 kWe Brayton power system
Electrically-heated Brayton power conversion system, comparing performance tests with prediction
Results of the automated power systems management /APSM/ program and future technology implementation
The APSM program was initiated in 1975. The purpose of this program was to develop and demonstrate the technology and benefits of autonomous operation of planetary spacecraft power systems to meet the projected requirements of future missions. Development of the APSM program was based on implementing a selected set of autonomous functions in a state-of-the-art breadboard power system. A distributed microcomputer system was developed to implement the functions. Several critical programmatic elements were identified as necessary to implement autonomous functions. These elements, including proper skill combination, well defined autonomous functions, and management of the software design and development task, were found to be more significant than hardware management. The incorporation of APSM technology in future space programs is also discussed.