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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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Instantaneous thickness of a frozen layer is a function of specific heat, heat of fusion, temperatures, the frozen layer thickness at equilibrium, the thermal conductivity, and heat transfer coefficient. The equation can be evaluated on a desk calculator.
Critical flow factor is calculated that permits the isentropic mass-flow rate of the gases through critical flow nozzles to be calculated from plenum conditions. Results include nozzle throat velocity, compressibility factor, entropy, enthalpy, specific heat, and ratios of throat to plenum pressure, density, and temperature.
Thermodynamic and transport properties include ratio of specific heats, molecular weight, viscosity, heat capacity, thermal conductivity, and Prandtl number. Properties are calculated from 300 to 2500 degrees K and for pressures of three and ten atmospheres.
Experimental measurements of thermal conductivity, electrical resistivity, and specific heat with hot pressed beryllium specimens
Conditions for subsonic compressible flow through duct systems are quickly and easily calculated using compact series of curves showing dimensionless parametric functions of Mach number and specific heat ratio. Method is directly applicable to analysis and design of compressible flow systems in industrial fields or processes.
Although thermocouple calibration tables of emf (mv abs) vs temperature usually have enough significant digits for many purposes, the rounding errors often limit the use of these tables (and hence thermocouples) for precise measurements of temperature related effects such as thermal conductivity or specific heat. Fourteen calibration tables for common thermocouples from NBS Circular 561 and for cryogenic thermocouples from NBS Report 9712 were smoothed, and these are given in vol. 2 of this report. In this volume (vol.1), a general discussion of data smoothing techniques and a description of the procedures by which the smoothed tables were prepared are given.
Magnon energy theory for temperature dependence of ferrous and magnesium fluorides antiferromagnetic- resonance frequency, sublattice magnetization and magnetic specific heat
Calorimetric measurements for Re specific heat in normal and superconducting states, comparing to theoretical calculation
Apollo 11 rocks IR absorption properties, specific heat and thermal conductivity, discussing heat flow in surface layer
Set of FORTRAN 4 subroutines to calculate mass flow rate of natural gas through nozzles, also thermodynamic functions such as compressibility factor, entropy, enthalpy, and specific heat
Specific heat, absorptance, and emittance of thermal control coatings determined simultaneously by cyclic radiation technique
Flux pinning mechanisms in type-2 semiconductors and specific heat measurements on annealed and deformed pure niobium samples
Apollo 11 and 12 rocks specific heat and thermal conductivity at 2-5 K, comparing elastic properties
Subroutines, FORTRAN 4 type, were developed for calculating isentropic natural gas mass flow rate through nozzle. Thermodynamic functions covering compressibility, entropy, enthalpy, and specific heat are included.
The contact of two rough, wavy surfaces; the contact of two rough but nominally flat plates pressed together over a concentrated area; and the contact of two rough but nominally flat plates bolted together are considered. In each case the pressure distribution is calculated as a function of the surface properties. In the case of wavy surfaces it is found that all necessary information for any combination of parameters can be reduced to one master graph. In the other two cases one such graph is needed for each geometry used. The resulting pressure distributions are used in a specific heat transfer example and the total joint resistance versus roughness is presented. A method for decreasing the resistance by increasing the roughness is shown.
The tables include entropy, enthalpy, internal energy, density, volume, speed of sound, specific heat, thermal conductivity, viscosity, thermal diffusivity, Prandtl number, and the dielectric constant for 65 isobars. Quantities of special utility in heat transfer and thermodynamic calculations are also included in the isobaric tables. In addition to the isobaric tables, tables for the saturated vapor and liquid are given, which include all of the above properties, plus the surface tension. Tables for the P-T of the freezing liquid, index of refraction, and the derived Joule-Thomson inversion curve are also presented.
A computer study was conducted to compare the numerical behavior of two approaches to describing the thermodynamic properties of oxygen near the critical point. Data on the relative differences between values of specific heats at constant pressure (sub p) density, and isotherm and isochor derivatives of the equation of state are presented for selected supercritical pressures at temperatures in the range 100 to 300 K. The results of a more detailed study of the sub p representations afforded by the two methods are also presented.
The diurnal variation of temperatures in the lunar surface layer is calculated using the measured properties of the Apollo 12 samples. The results are compared with similar calculations made using data from the Apollo 11 samples and with previous infrared temperature measurements. Comparisons are also made with prior calculations which used assumed properties. These are based on an effective value of the thermal parameter (gamma) of 1034 which is obtained from integrated average values of the specific heat and thermal conductivity of the Apollo 12 fines.