SENFTLEBEN-BEENAKKER EFFECTS FOR A GAS OF ROUGH SPHERICAL MOLECULES .2. VISCOSITY SCHEME

The changes occuring in the shear and bulk viscosities upon the application of an external magnetic field are studied for a gas consisting of rough spherical molecules. An applied magnetic field not only alters these transport coefficients, it also causes a cross-coupling between the shear and bulk effects; the coefficients describing this cross-coupling are evaluated for this model. In particular, (i) the influence of polynomials in the variables W2 (W represents the reduced peculiar velocity) and Ω2 (Ω represents the reduced rotational angular momentum) employed in the expansion for the shear viscosity effect is studied and shown to be negligible; (ii) the influence of the tensorial expansion tensors [Ω](2), Ω[W](2) and [Ω](2) [W](2) are examined using certain commonly employed approximations, the result being that the [Ω](2) term alone is shown to account almost entirely for the shear viscosity effect; (iii) the relative change in the bulk viscosity and the cross-coefficients are shown (for the rough sphere) to be approximately 50, respectively, 1000 times smaller than the corresponding change in the shear viscosity. All numerical results have been presented in graphical form. © 1969.