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Thermal conductivities of ten gases and selected binary and ternary mixtures of them were measured in a concentric silver cylinder cell over the temperature range from 100° to 540°C. The gases were helium, argon, nitrogen, oxygen, carbon dioxide, methyl ether, and methyl formate. Correlations based upon empirical equations derived from kinetic theory have been developed for the thermal conductivity of gas mixtures. For mixtures of polyatomic molecules the energy transport is considered in two parts, that is one portion transferred by collision and the other by diffusion. When compared with the experimental data for 226 binary mixtures over temperatures from 0° to 774°C., the conductivity equation proposed in this work shows an average deviation of 2.1%.

Test firings of solid propellant research rockets were made to study effects of propellant composition, pressure, and engine size on the exhaust oxide particle size, and on the composition of the solid exhaust products. The experimental results of this work and those reported by others were analyzed collectively to provide a reasonable description of the aluminum combustion and oxide condensation processes in solid propellant rocket motors. Combustion of aluminum was found to occur in the vapor phase, and was essentially complete in the engines studied although some combustion took place in the nozzle. The experimental results indicate that condensation of the oxide vapor can be described by first-order chemical kinetics. Further particle growth by agglomeration appears likely. The effect of two phase flow was found to be significant in the motors tested and reached a maximum in motors of a certain size. In motors where this loss is large, significant improvement in delivered performance can be realized by reducing the aluminum content.

Correlations based upon empirical modified equations derived from kinetic theory were developed for the thermal conductivity and viscosity of gas mixtures. The conductivity equation was compared to 226 binary mixture conductivities in temperatures from 0 to 774 deg C from the literature and this work. The average deviation is 2.1%. In correlating conductivity data of mixtures of polyatomic molecules, the energy transport is considered in two parts, i.e., one protion transferred by collision and the other by diffusion. The proposed viscosity equation reproduces 103 binary data points with an average deviation of 1.3%. These equations are more consistent with experiment than existing correlations in the literature. the relation of the conductivity or viscosity to composition and temperature are discussed in the light of the proposed equations. It has been demonstrated that, at a given composition, the ratio of the measured conductivity to that calculated on the molar average basis for mixtures of most simple molecules and the ratio of the measured viscosity to that calculated on the molar average basis for mixtures of most gases should be nearly constant over a temperature range of 200 to 300 deg C. The thermal conductivity of ten gases and selected binary and ternarymore » mixtures of them were measured in a concentric silver cylinder cell in the temperature range of 100 to 540 deg C The gases are He, A, N/sub 2/, O/sub 2/, CO/sub 2/, CH/sub 4/, C/sub 2/ H/sub 4/, C/sub 3/H/sub 8/, methyl ether , and methyl formats. (auth)« less