Char reflectances and planetary entry heat shields
Optical reflectance measurements of pyrolytic graphite and phenolic nylon chars and potential application to heat shield requirements
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Optical reflectance measurements of pyrolytic graphite and phenolic nylon chars and potential application to heat shield requirements
Conductive heat transfer in porous carbonaceous chars of degraded phenolic nylon sample
Ablative behavior of low and high density phenolic nylon in diffusion controlled surface combustion regime
Space environmental effects on filled elastomers, nylon parachute material and adhesion of metals
Long manned missions require food packaging to maintain food safety, nutrition, and acceptability for the length of 3-5 years1,2 while the shelf life assigned by NASA for current provisions is 18-24 months1. The focus of this design project was to make a polymer film specifically to function as a high oxygen barrier to later be included in an improved multi-layer packaging system of other specialized polymers with capabilities to allow for a 5-year shelf-life. To qualify as a high oxygen barrier film and to be a successful design for the future packaging, the resulting film is required to have an oxygen transmission rate (OTR) less than 0.06 cc/ m2/24 hr/atm, the standard for the current packaging3. This new film was designed to have a decreased permeability by increasing the “tortuous path” a gas molecule travels to permeate through a film. The increase in the “tortuous path” of a gas molecule is accomplished by introducing a 2D material additive. The additive chosen for this project was hexagonal boron nitride (h-BN) which exfoliates into boron nitride nanosheets (BNNs). Nylon 6 was chosen as the candidate for the matrix. This project is required to determine the best methods to synthesize the sample film and then to test the OTR of the film to determine if this design was successful. This project examined methods for pulverizing polymer resin pellets, h-BN exfoliation, and film fabrication using a hot press. This report includes the exfoliation and analysis of h-BN, procedural preparations for films, and a modeling study of estimated OTR of the h-BN/Nylon. The work in this report did not yield a high barrier composite film because of the laboratory closure in response to COVID -19 guidance but provides a concise method of the additive preparation and film synthesis. This gives a good starting point for future research in high barrier films by 2D additive composites.
To protect curved, finished surface and provide support for workmen, portable flooring has been made from rigid plastic foam blocks, faced with aluminum strips. Held together by nylon webbing, the flooring can be rolled up for easy carrying.
This paper covers the general structural and thermal design considerations of the Telstar satellite. The basic objectives were to maintain the electronic components in a near room temperature environment and to protect the electronics packge from high-frequency vibration excitation. These objectives were realized by dividing satellite into two lumped masses, the shell and the centrally located electronics package, and by utilizing nylon lacing for support of the electronics package. The package was provided with an active temperature control, regulating radiative heat flow between the skin and the package. Results of on-the-ground experimental evaluation and of telemetry data are given.
Thermophysical property data for ablation materials - aerodynamic heating of low density phenolic nylon and filled silicone resin
Adhesive cured at room temperature provides an effective adhesive bond over the range from room temperature down to the temperature of liquid hydrogen. The adhesive consists of one part of 200-mesh powdered nylon filler to two parts of an epoxy-polyamine resin.
Microphone used as a phonocardiograph transducer monitors small amplitude audio signals in the presence of large shock loads and high humidity. It contains a lead zirconate-lead titanate piezoelectric plate encapsulated in a flexible polyurethane resin. The resin is contained in a sealed nylon case having a diameter of less than one inch.
Workpieces covered with phenolic impregnated asbestos tape and then wrapped with a specified thickness of nylon yarn under pressure, are debulked and cured in a standard oven. This method of debulking and curing is used in the fabrication of ablative chambers for the Gemini and Apollo attitude control engines.
Scout vehicle flight experiment to determine performance of phenolic nylon spacecraft heat shield material under reentry conditions
Temperature and material effects on high-velocity impact craters in phenolic-nylon and elastomeric ablative heat-shield materials
Double wall ablative heat shield panels for manned lifting entry vehicles, noting nylon phenolic and elastomeric silicone ablators
Transverse forced vibration of viscoelastic nylon filament under stretching and tension changes
Reflectance of pyrolytic graphite and phenolic nylon chars for radiant heat rejection from nonablating heat shield
Performance evaluation of low density phenolic nylon, and elastomeric ablative composites
Hypervelocity heat protection, surface heat shielding, and internal temperature rise of Teflon, phenolic nylon, epoxy resin in glass honeycomb, and silicone elastomer