混合布纳特方程

在 Chapman & Enskog 版本的布纳特方程中，压力张量和热流中的两个时间导数被用 Knudsen 数零阶方程替换为空间导数。Bobylev 证明了 resulting conventional Burnett equations are linearly unstable。In this paper it is shown that if the time derivatives are instead kept, the equations. A hybrid of the two possibilities is proposed which gives equations which are shown to be linearly stable. The system contains two parameters. For the simplest choice of parameters the hybrid equations have no third derivative of the temperature but the inertia term contains second spatial derivatives. For stationary flow, when terms $Kn^2Ma^2$ can be neglected, the only difference from the conventional Burnett equations is the change of coefficients $\varpi_{2}\to\varpi_{3},\varpi_{3}\to\varpi_{3}$.