The Burnett shock structures in low density hypersonic flows

One-dimensional shock structures in low density hypersonic flows have been studied numerically by solving the Burnett and Navier-Stokes equations. A new lower-upper scheme has been developed to obtain the steady and stationary normal shock solutions by the time-marching technique. The new scheme directly employs the implicit finite difference method without computing the eigenvalues, and it is first-order accurate in time and second-order accurate in space. The computed shock structures have been compared with available experimental data, and they are in good agreements. Numerical results show that the Burnett calculations has less numerical diffusion than the Navier-Stokes calculations does. As to the shock thickness, the Burnett solutions are apparently superior than the Navier-Stokes solutions.