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Strauss, E. L.

Publications and source records attributed to Strauss, E. L..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

Producibility of fibrous refractory composite insulation, FRCI 40-20

Fibrous Refractory Composite Insulation (FRCI) is a NASA-developed, second generation, reusable heat-shield material that comprises a mixture of aluminoborosilicate fibers, silica fibers, and silicon carbide. Under NASA contract, a program was conducted to demonstrate the capability for manufacturing FRCI 40-20 billets. A detailed fabrication procedure was written and validated by testing specimens from the first two billets. The material conformed to NASA requirements for density, tensile strength, modulus of rupture, thermal expansion, cristobalite content, and uniformity. Twenty-four billets were prepared to provide 20 deliverable articles. Production billets were checked for density, modulus of rupture, cristobalite content, and uniformity. Billet density ranged from 309.48 to 332.22 kg/cu m (19.32 to 20.74 lb/cu ft) and modulus of rupture from 4690 to 10,140 kPa (680 to 1470 psi). Cristobalite content was less than 1 percent. A Weibull analysis of modulus-of-rupture data indicated a 1.5 percent probability for failure below the specified strength of 4480 kPa (650 psi).

Strauss, E. L.↗
NASA NTRS1977

Evaluation of low cost/high temperature fiber and blanket insulation

Twelve fiber materials comprising water-felted fiber cakes and blanket insulation were subjected to furnace exposures at 1000, 1200, 1400, and 1600 C for up to 500 hours to establish the time-temperature limits below which these insulation materials can withstand repeated thermal cycles without detrimental shrinkage, thermal conductivity increase, or physical changes. Test samples were inspected periodically during the exposure cycles and weight loss and dimensional shrinkage were measured. Density, fiber crystallography, and thermal conductivity were measured after exposure and properties were compared with those of unexposed controls.

Strauss, E. L.↗
NASA NTRS1975

Evaluation of low cost/high temperature insulation, July 1974 - June 1975

Six fiber products and six insulation blankets comprising silica, alumina, zirconia, mullite, and mixed ceramic systems were subjected to furnace exposures up to 500 hours at temperatures of 1000 to 1600 C and evaluated for chemical and dimensional stability and for changes in thermal conductivity. Alumina, zirconia, and mullite fibers were fabricated into reusable surface insulation (RSI) tile by water-felting and reimpregnation with ethyl silicate. Specimens were exposed to 25 thermal cycles at 1200 C and 1400 C and a pressure of 10 and 32 torr, respectively. Production costs for 930 sq m (10,000 sq ft) of blanket insulation and of alumina RSI tile were developed.

Strauss, E. L.↗
NASA NTRS1975

Ablative overlays for Space Shuttle leading edge ascent heat protection

Ablative overlays were evaluated via a plasma-arc simulation of the ascent pulse on the leading edge of the Space Shuttle Orbiter. Overlay concepts included corkboard, polyisocyanurate foam, low-density Teflon, epoxy, and subliming salts. Their densities ranged from 4.9 to 81 lb per cu ft, and the thicknesses varied from 0.107 to 0.330 in. Swept-leading-edge models were fabricated from 30-lb per cu ft silicone-based ablators. The overlays were bonded to maintain the surface temperature of the base ablator below 500 F during ascent. Foams provided minimum-weight overlays, and subliming salts provided minimum-thickness overlays. Teflon left the most uniform surface after ascent heating.

Strauss, E. L.↗
NASA NTRS1974

Ablative thermal protection for space tug multipass, aerobraking entry

Analytical studies had found the employment of an aerobraking trajectory for return of a reusable Space Tug from geosynchronous missions to be feasible and practical. To establish the minimum-weight ablative dome heat shield, trajectories involving 2 and 30 perigee passes were investigated both analytically and by plasma arc testing. Silicone-base ablators with densities of 15, 30, and 50 lb/cu ft were selected for evaluation. All models withstood the multipass exposures without deleterius surface recession or char erosion. Dome heat shield weights based on optimum ablative compositions indicated that ablators are a highly efficient thermal protection system for these missions.

Strauss, E. L.↗