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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1971

Fundamental ignition study for material fire safety improvement, part 2

The autoignition behavior of polymeric compositions in oxidizing media was investigated as well as the nature and relative concentration of the volatiles produced during oxidative decomposition culminating in combustion. The materials investigated were Teflon, Fluorel KF-2140 raw gum and its compounded versions Refset and Ladicote, 45B3 intumenscent paint, and Ames isocyanurate foam. The majority of the tests were conducted using a stagnation burner arrangement which provided a laminar gas flow and allowed the sample block and gas temperatures to be varied independently. The oxidizing atmospheres were essentially air and oxygen, although in the case of the Fluorel family of materials, due to partial blockage of the gas inlet system, some tests were performed unintentionally in enriched air (not oxygen). The 45B3 paint was not amenable to sampling in a dynamic system, due to its highly intumescent nature. Consequently, selected experiments were conducted using a sealed tube technique both in air and oxygen media.

Paciorek, K. L.↗
NASA NTRS1972

Hydrogen-oxygen catalytic ignition and thruster investigation. Volume 2: High pressure thruster evaluations

A high pressure thruster effort was conducted with the major objective of demonstrating a duct cooling concept with gaseous propellant in a thruster operating at nominally 300 psia and 1500 lbf. The analytical design methods for the duct cooling were proven in a series of tests with both ambient and reduced temperature propellants. Long duration tests as well as pulse mode tests demonstrated the feasibility of the concept. All tests were conducted with a scaling of the raised post triplet injector design previously demonstrated at 900 lbf in demonstration firings. A series of environmental conditioned firings were also conducted to determine the effects of thermal soaks, atmospheric air and high humidity. This volume presents the results of the high pressure thruster evaluations.

Johnson, R. J.↗
NASA NTRS1973

Study of exothermic processes in shock ignited gases by the use of laser shear interferometry.

The paper reports on the measurements of maximum exothermic power pulses attainable from a given chemical system. Experimental tests involved the use of a shock tube technique whereby the exothermic process of combustion was controlled by reflected shock so that it occurred under virtually inviscid flow conditions, the data having been obtained at a resolution commensurate with the actual rate of chemical reaction. Experimental observations were made by means of a novel method of laser shear interferometry. Chemical systems treated in this manner comprised of mixtures of stoichiometric hydrogen-oxygen with 80 and 90% argon, while the measurements covered the full permissible range of initial thermodynamic conditions.

Meyer, J. W.↗
NASA NTRS1973

Study of exothermic processes in shock ignited gases by the use of laser shear interferometry

Report on measurements of maximum exothermic power pulses attainable from a given chemical system. Experimental tests involved the use of a shock tube technique whereby the exothermic process of combustion was controlled by reflected shock, so that it occurred under virtually inviscid flow conditions, while the measurements were performed at a resolution commensurate with the actual rate of chemical reaction. Experimental observations were made by means of a novel method of laser shear interferometry - a cross-breed between holography and the conventional means for measuring refractive index fields, in that, on one hand, it was based on the exploitation of the phase coherence of the laser light beam, recording first a diffraction image of the wave fronts which, for the desired final result, had to be optically reconstructed, and, on the other, it yielded eventually either two-dimensional interferograms or schlieren photographs of the observed phenomena.

Meyer, J. W.↗
NASA NTRS1976

Apollo experience report: Detection and minimization of ignition hazards from water/glycol contamination of silver-clad electrical circuitry

The potential flammability hazard when a water/glycol solution contacts defectively insulated silver-clad copper circuitry or electrical components carrying a direct current is described. The chemical reactions and means for detecting them are explained. Methods for detecting and cleaning contaminated areas and the use of inhibitors to arrest chemical reactivity are also explained. Preventive measures to minimize hazards are given. Photomicrographs of the chemical reactions occurring on silver clad wires are also included.

Downs, W. R.↗
NASA NTRS1975

Electronic delay ignition module for single bridgewire Apollo standard initiator

An engineering model and a qualification model of the EDIM were constructed and tested to Scout flight qualification criteria. The qualification model incorporated design improvements resulting from the engineering model tests. Compatibility with single bridgewire Apollo standard initiator (SBASI) was proven by test firing forty-five (45) SBASI's with worst case voltage and temperature conditions. The EDIM was successfully qualified for Scout flight application with no failures during testing of the qualification unit. Included is a method of implementing the EDIM into Scout vehicle hardware and the ground support equipment necessary to check out the system.

Ward, R. D.↗