Ablation and luminosity of artificial meteors
Artificial meteors ablation and luminosity measurements, using ballistic range shadowgraph and radiometric equipment for velocity history, shock wave formation and mass loss process
Givens, J. J.↗
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Results for “ablator”
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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An exploratory study of the roll behavior of ablating cones
Cone roll dynamics-ablation patterns coupling in hypersonic wind tunnels
Mcdevitt, J. B.↗
Characterization of an epoxy-anhydride ablative system using computer treatment of analytical results
Epoxy novolac resin-cured alicyclic anhydride amine-catalyzed ablative polymers molecular structure from computer correlation of analytical data
Pendleton, E. L.↗
The synthesis and characterization of some potential ablative polymers
Ablative polymers synthesis from formaldehyde, phenols and ethers reaction products, discussing char yield, thermally stable fillers incorporation and thermogravimetric analysis
Eddy, R.↗
Graphite ablation at high temperatures
Graphite ablation under high temperatures for large outer planets entry probes, correlating mass loss rates with surface temperatures and specimen nose cone radii
Dickey, R. R.↗
Radiative, ablative, and active cooling thermal protection studies for the leading edge of a fixed-straight wing space shuttle
Performance prediction of fixed wing leading edges radiative, ablative and active cooling thermal protection systems and system weights comparison for space shuttle entry mission
Curry, D. M.↗
Modeling reacting gas flow in the char layer of an ablator
Nonequilibrium modeling of pyrolysis gas products flow through char layer of ablative heat shield
April, G. C.↗
Ablation and breakup of large meteoroids during atmospheric entry
Large meteoroids ablation and breakup mathematical model, estimating Mars atmosphere effectiveness as shield against surface impact craters production
Baldwin, B.↗
Summary of the NASA-SRI Round Robin Ablation Program
NASA-SRI Round Robin Ablation Program summary, discussing dimensional analysis, Teflon, nylon and surface temperature
Clark, C. F.↗
Ablative heat shields for Jupiter entry probes
Jupiter atmosphere entry probes graphite ablative heat shields performance, indicating convective and radiative blockage and graphite sublimation processes in surface heat balance
Lundell, J. H.↗
Reflecting and ablating heat shields for radiative environments
Reflecting and ablating Teflon heat shields for radiative environment of outer planets atmosphere
Howe, J. T.↗
Chemical modification of poly(p-phenylene) for use in ablative compositions
Development of ablative materials based on modification of polyphenylene compounds is discussed. Chemical and physical properties are analyzed for application as heat resistant materials. Synthesis of linear polyphenylenes is described. Effects of exposure to oxyacetylene flame and composition of resultant char layer are presented.
Parker, J. A.↗
Study of critical defects in ablative heat shield systems for the space shuttle
Results are presented from an investigation to determine the effects of fabrication-induced defects on the performance of an ablative heat shield material in a simulated space shuttle reentry environment. Nondestructive methods for detecting the defects were investigated. The material considered is a fiber-filled, honeycomb-reinforced, low-density elastomer. Results were obtained for density variations, voids, fiber bundles, crushed honeycomb, undercut honeycomb, unbonded areas, face sheet delaminations, and cure variations. The data indicate that, within reasonable tolerances, the fabrication defects investigated are not critical in terms of reentry performance of the heat shield.
Thompson, R. L.↗
Development of a silicone ablator for high-heat-flux and high-shear-rate condition
A silicone material was developed which gives suitable ablative protection in the high heat flux, high shear environments encountered in severe reentry applications, such as nose cones for ballistic vehicles and protection of leading edges or other critical areas of a vehicle. In addition, the ease of handling, low application cost, and room temperature cure make such a silicon material suitable nozzles for the large rockets necessary for vehicle launching. The development of this product is traced from the selection of suitable polymers through the choice of fillers and the finalization of filler loadings.
Campbell, R. A.↗
Design and evaluation of an oxidant-fuel-ratio-zoned rocket injector for high performance and ablative engine compatibility
A method for temperature control of the combustion gases in the peripheral zone of a rocket combustor which would reduce ablative throat erosion, prevent melting of zirconia throat inserts, and maintain high combustion performance is discussed. Included are techniques for analyzing and predicting zoned injector performance, as well as the philosophy and method for accomplishing an optimum compromise between high performance and reduced effective gas temperature. The experimental work was done with a 1000-lbf rocket engine which used as propellants N2O4 and a blend of 50-percent N2H4 and 50-percent UDMH at 100-psia chamber pressure and an overall O/F of 2.0. The method selected to provide temperature control was to use 30 percent of the propellant to form a peripheral zone of combustion gases at an O/F of 1.31 and 2700 K. The remaining 70 percent of the propellant in the core was at an O/F of 2.45 to keep the overall O/F at 2.0.
Winter, J. M.↗
Ablator manufacturing
Studies are being conducted to determine how manufacturing-induced defects affect the performance of ablative heat shields. If commonly occurring defects do not affect material performance, simpler manufacturing techniques can be used, quality control requirements can be relaxed, repair and rework operations can be held to a minimum, and thus the total manufacturing cost can be reduced.
Pittman, C. M.↗
Low-cost fabrication and direct bond installation of flat, single-curvature and compound-curvature ablative heat shield panels
Procedures for low cost fabrication and direct bond installation of flat, single curved, and compound curvature ablative heat shields on a DC-3 aircraft are discussed. The panel sizes and attachment locations are identified. In addition to the bonding of the four contoured panels, two flat panels were bonded to the nearly flat, lower surface of the center wing section. The detailed requirements and objectives of the investigation are described.
Norwood, L. B.↗
Numerical analysis of the transient response of an axisymmetric ablative char layer considering internal flow effects
The differential equations governing the transient response of the char layer of an ablating axisymmetric body, internal pyrolysis gas flow effects being considered, have been derived. These equations have been expanded into finite difference form and programed for numerical solution on a digital computer. Numerical results compare favorably with simplified exact solutions. The complete numerical analysis was used to obtain solutions for two representative body shapes subjected to a typical entry heating environment. Pronounced effects of the lateral flow of pyrolysis gases on the mass flow field within the char layer and the associated surface and pyrolysis interface recession rates are shown.
Pittman, C. M.↗