Numerical investigation of dynamic properties of plasma sheath with pitching motion

Research on the dynamic properties of a plasma sheath coupled with pitching motion of the vehicle has great significance in solving the problem of communication interruption in the process of vehicle reentry. This paper investigates the dynamic properties of the plasma sheath by using the simplified conventional Burnett (SCB) equations and the Navier-Stokes (NS) equations with the thermochemical non-equilibrium effect. The eleven-species chemical kinetic models are applied to the comparison and there is verification of a dynamic plasma sheath simulation for the first time. After the introduction of vehicle pitching motion, the dynamic results are more consistent with the experimental data than the simulated results when treating it as static state. The plasma sheath characteristic parameters show periodic properties, whose changing period is the same as the pitching motion period. However, because of different velocities of the pitching motion, phase shifts exist in different positions of the vehicle. The enhancement of the rarefied effect weakens the disturbance to the plasma sheath. This research reveals the distribution and regularities of the dynamic plasma sheath. It is significant in solving the ionization blackout problem and the design of the reentry vehicle, and provides reliable data for further research on the dynamic plasma sheath.