Plasma hydrodynmics with account for relaxation degrees of freedom

The hydrodynamics of a completely ionized two-component electron-ion plasma is investigated on the basis of a generalized Chapman-Enskog method. The generalization is made in order to account for relaxation processes in the plasma. The term “relaxation” is used here in a narrow sense as a process which can take place in a spatially homogenous system. Known results which are devoted to plasma hydrodynamics and plasma kinetic coefficients coincide with the Braginsky results in the case of small gradients. Braginsky's work is based on the local equilibrium assumption (LEA) and does not account for relaxation terms in the calculation of fluxes. In contrast to Braginsky, we obtain corrections to the LEA and we calculate the distribution functions and fluxes with account for spatially uniform relaxation processes.