Combined Translational and Relaxational Dispersion of Sound in Gases

Abstract

It is shown that for a special value of the Prandtl number the Stokes-Kirchhoff equation governing the propagation of sound in a fluid is factorizable even for complex values of the heat conductivity and specific heats. A solution allowing for the dispersion due to both translational and thermal relaxation is thus obtained in simple form for this special case which, however, is representative of many gases with considerable accuracy.