Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “kW”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 937 records · Page 52

Design and fabrication of the Brayton rotating unit

The Brayton rotating unit (BRU), operating on a gas bearing system, has been designed, fabricated, and demonstrated for use in a closed Brayton cycle space power conversion system. The BRU uses a binary mixture of xenon and helium (molecular weight, 83.8) as the cycle working fluid and bearing lubricating medium and was designed to produce from 2.25 to 10.5 kw sub e of 1200 Hz three-phase electrical power. The single-shaft rotating assembly operates at a design speed of 36,000 rpm and comprises a radial single-stage compressor, a four-pole Rice alternator rotor, and a radial inflow turbine. Four units, a dynamic simulator and three component research packages, were supplied to the NASA Lewis Research Center for performance testing and further development.

Davis, J. E.↗

Development of a high irradiance source

Irradiance levels up to 17.27 sq in/sec. with a nonuniformity ratio of 1.07 have been developed to simulate high heat flux loads on the surface of difference materials. This has been achieved by an arc image furnace utilizing a 50 kw xenon short arc lamp mounted within an elliptical collector.

Lunde, A. R.↗

Alternator insulation evaluation tests

Tests were conducted to predict the remaining electrical insulation life of a 60 KW homopolar inductor alternator following completion of NASA turbo-alternator endurance tests for SNAP-8 space electrical power systems application. The insulation quality was established for two alternators following completion of these tests. A step-temperature aging test procedure was developed for insulation life prediction and applied to one of the two alternators. Armature winding insulation life of over 80,000 hours for an average winding temperature of 248 degrees C was predicted using the developed procedure.

Penn, W. B.↗

An out-of-core thermionic-converter system for nuclear space power

Design of the nuclear thermionic space power system, 40 50 70 Kw(e) power range, are given. The design configuration (1) meets the constraints of readily available launch vehicles; (2) allows for off-design operation including startup, shutdown, and possible emergency conditions; (3) provides tolerance of failure by extensive use of modular, redundant elements; (4) incorporates and uses heat pipes in a fashion that reduces the need for extensive in-pile testing of system components; and (5) uses thermionic converters, nuclear fuel elements, and heat transfer devices in a geometrical form adapted from existing incore thermionic system designs. Designs and in some cases performance data for elements and groups of the elements of the system are included. Benefits of the highly modular system approach to reliability, safety, economy of development, and flexibility are discussed.

Breitwieser, R.↗

Induction torches and low frequency tests

Three induction-coupled plasma torches were operated at 9600 Hz to determine specific operating parameters and supply data for gas core nuclear rocket simulation studies. Two air-cooled torches, one 16 cm in diameter and one 30 cm in diameter, and a water-cooled torch 14 cm in diameter, were tested. Complete energy balances for the operating systems were obtained during operation. A series of operating points, including pressures from 30 torr to 1 atmosphere, power levels up to 343 kw, and gas flows from 1.1 to 35 g/sec, were documented. Complete operating data for approximately thirty runs are presented, along with graphs of significant operating parameters.

Poole, J. W.↗

Operating features of an ion-cyclotron-wave plasma apparatus running in the RF-sustained mode

An experimental study has been made of an ion-cyclotron-wave apparatus operated in the RF-sustained mode. This is a mode in which the Stix RF coil both propagates the waves and maintains the plasma. Problems associated with this method of operation are presented. Some factors that are important to the coupling of RF power are noted. In general, the wave-propagation and wave-damping data agree with theory. Some irregularities in wave fields are observed. Maximum ion temperature is 870 eV at a density of 5 times 10 to the 12th power per cubic centimeter and RF power of 90 kW. Coupling efficiency is 70 percent.

Swett, C. C.↗

Study of a comet rendezvous mission, volume 1

The feasibility, scientific objectives, modes of exploration and implementation alternatives of a rendezvous mission to Encke's comet in 1984 are considered. Principal emphasis is placed on developing the scientific rationale for such a mission, based on available knowledge and best estimates of this comet's physical characteristics, including current theories of its origin, evolution and composition. Studied are mission profile alternatives, performance tradeoffs, preferred exploration strategy, and a spacecraft design concept capable of performing this mission. The study showed that the major scientific objectives can be met by a Titan IIID/Centaur-launched 17.5 kw solar electric propulsion spacecraft which carries 60 kg of scientific instruments and is capable of extensive maneuvering within the comet envelope to explore the coma, tail and nucleus.

Source record↗

Ionospheric heating at Arecibo - First tests.

Ionospheric F-region heating by a high-frequency transmitter (100 kW at 5.62 MHz fed into a 1000-ft dish producing a beam with an angular half-width of 10 deg) was observed with a 430-MHz incoherent scatter radar, an ionosonde, and several photometers. The electron temperature of the ionosphere was increased by as much as 30% at and just below the height where the local plasma frequency was equal to the frequency of the heating transmitter. Calculations show time constants of 40 sec for electron heating and less than 10 sec for the cooling at 308 km when the heating transmitter was operated in a pulsed mode.

Gordon, W. E.↗

Multi-phase, 2-kilowatt, high-voltage, regulated power supply.

Development of a flight configured experimental power supply delivering 2 kw of conditioned power represents a concentrated effort at advancing the state-of-the-art in high voltage power supplies for space application. The power supply described herein was designed for use with the Jet Propulsion Laboratory (JPL) 20 cm Mercury Ion Thruster. However, its modularized design philosophy allows adaptation to various high voltage, high power requirements. Areas of principal concern are design of power and control circuits, performance parameters, packaging, efficiency, and weight.

Garth, D. R.↗

Experimental investigation to simulate propellant heating in the nuclear light bulb engine.

Experiments to heat a simulated propellant to high bulk temperatures by the absorption of thermal radiation are discussed. Argon seeded with micron-sized carbon particles was used as the simulated propellant; a 500 kw d-c arc was used as the radiant energy source. Bulk temperatures up to 3860 K were obtained with greater than 95% of the incident radiation absorbed. The arc radiation source, seed dispersal equipment, techniques used to prevent transparent wall coating by the seeds, and calorimetric measurement of bulk temperature are also discussed.

Klein, J. F.↗

Gain and power of CO2 gasdynamic lasers.

This paper presents experimental and theoretical studies of the small signal gain and the radiant power for one configuration of CO2 gasdynamic lasers to define the optimum-gas temperature, pressure and gas compositions for the gain and the laser power. The laser was operated with two gas mixtures (CO2-N2-He and CO2-N2-H2O) at temperatures of 800-2200 deg K, pressures of 2-16 atm, and a wide range of gas compositions. For this laser optimum gas temperatures were roughly 1500-1600 deg K for gain and more than 2200 deg K for power. It was found that the gasdynamic laser would not oscillate for He or H2O concentrations of less than 10% and 1%, respectively. The various kinetic processes for establishing gain and the various laser cavity parameters that determine laser power were examined. The theories were assessed for their ability to predict gain and power. In most cases, the gain theory gave excellent quantitative results whereas the power theory gave only qualitative results. Laser power of nearly 2 kw was obtained.

Lee, G.↗