The phenomenological coefficients for mass and energy flows due to axial pressure and to temperature gradients on long capillary tubes containing a polyatomic gas at all degrees of rarefaction are reported. The Hansen and Morse polyatomic gas model of the linearized Wang Chang and Uhlenbeck equation was used together with Maxwellrsquo;s diffuse scattering boundary conditions. The results are consistent with previous results obtained for flow between parallel plates. Experimental isothermal flow data are nearly quantitatively represented by the theory in the transition flow regime (Knudsen number sim; 1). Experimental thermal transpiration effect ratios (Dgr;p/p0)/(Dgr;T/T0) are also quantitatively represented for simple gases, argon, air, and carbon dioxide. Thermal transpiration measurements on sulfur dioxide correlate as the other gases but the transpiration effect ratio is not quantitatively given by the theory due to inadequacy of the Hansenndash;Morse model and the continuum theory for strongly polar gases.
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