Stability problems in a non-equilibrium gas

Fire consider the stability problem for a flat gas layer whose non-equilibrium state is maintained by pumping energy into the vibrational degrees of freedom of molecules and by heat transfer through the walls. We discuss two approaches to the study of gas stability, which consider the evolution of small hydrodynamic perturbations, and thermal explosion. We have studied in detail the Rayleigh-Benard problem of convection instability and the Semenov-Frank-Kamenetskii problem of thermal explosion, and generalised them to the case of a non-equilibrium gas. We have outlined some unsolved problems of the physical hydrodynamics of a non-equilibrium gas.