On the theory of bulk viscosity and relaxation pressure

A general theory of bulk viscosity and relaxation pressure, based on the generalized Chapman-Enskog method, is given, and also simple qualitative theories of them. Problems associated with the definition of temperature are discussed. Formulae are given for the bulk viscosity coefficient and the thermal conductivity of a gas possessing rotational degrees of freedom. The influence of bulk viscosity on the absorption and dispersion of sound and on the structure of a shock wave in nitrogen is investigated.