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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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Pool heating of liquid hydrogen in subcritical and supercritical pressure regimes over range of accelerations - effect on nucleate boiling
Heat exchange with carbon dioxide along supercritical isotherms under free convection
Heat transfer in supercritical region of carbon dioxide in turbulent flow in steel pipe
Convective heat transfer in supercritical region of carbon dioxide
Heat transfer and friction resistance for carbon dioxide in supercritical region
Transient heat and mass transfer analysis of supercritical cryogenic storage systems with spherical static heaters by computer program
Liquid shroud cryogenic supercritical pressure storage system for space applications
Apollo lunar module cryogenically stored supercritical He propellant tank pressurization system in descent propulsion subsystem, discussing design and performance tests
Supercritical He conditioning unit for servicing Lunar Module spacecraft storage tank noting functional performance
Investigation was made of the unstable behavior of a heat-transfer loop operating at a supercritical pressure. Natural convection operation of the loop, with observations on acoustic and slow oscillatory behavior, was emphasized during testing. The basic cause of both types of behavior appeared to originate in the heated boundary layer.
Supercritical burning of liquid fuel droplets in stagnant environment, using flame sheet model to obtain heat and mass fields
N-heptane and Freon-13 droplets vaporizing size and temperature at supercritical pressures in heated air stream
Combustion properties of Teflon insulated wires in supercritical oxygen at normal and zero gravities
Description of computer program for detailed stratification model of Apollo supercritical oxygen storage tank
N-heptane, carbon dioxide and Freon 13 droplet vaporization measurements at supercritical pressure, comparing with film theory calculation
Analytical model has been developed to predict possible unstable behavior in supercritical heat exchangers. From complete model, greatly simplified stability criterion is derived. As result of this criterion, stability of heat exchanger system can be predicted in advance.
The forebody drag of a supercritical body of revolution was measured in free flight over a Mach number range of 0.85 to 1.05 and a Reynolds number range of 11.5 x 10 to the 6th power to 19.4 x 10 to the 6th power and was compared with wind-tunnel data. The forebody drag coefficient for a Mach number less than 0.96 was 0.111 compared with the wind-tunnel value of 0.103. A gradual increase in the drag occurred in the Langley 8-foot transonic pressure tunnel at a lower Mach number than in the Langley 16-foot transonic tunnel or in the free-flight test. The sharp drag rise occurred near Mach 0.98 in free flight whereas the rise occurred near Mach 0.99 in the Langley 16-foot transonic tunnel. The sharp rise was not as pronounced in the Langley 8-foot transonic pressure tunnel and was probably affected by tunnel-wall-interference effects. The increase occurred more slowly and at a higher Mach number. These results indicate that the drag measurements made in the wind tunnels near Mach 1 were significantly affected by the relative size of the model and the wind tunnel.
A semiempirical design-oriented model has been developed for the prediction of the effects of thermal stratification on tank pressure and heater temperature response for the Apollo supercritical oxygen tank. The heat transfer formulation describes laminar free convection at low-g and takes into account the radiation and conduction processes occurring in the tank. The nonequilibrium thermodynamic behavior of the system due to localized heating of the stored fluid is represented by the characteristics of a discrete number of fluid regions and thermal nodes. Solutions to the time dependent variable fluid property problem are obtained through the use of a reference temperature procedure. A criterion which establishes the reference temperature as a function of the fluid density ratio is derived. The analytical results are compared with the flight data.