Analyses of Electromagnetic Properties of a Hypersonic Object With Plasma Sheath

Abstract

In this paper, we present a rigorous numerical approach for the electromagnetic (EM) analyses of a hypersonic object with plasma sheath. First, the effective EM parameters of the plasma flow are constructed by solving the Navier–Stokes fluid dynamics equation combined with proper thermochemical models. Then, the EM characteristics of the hypersonic complex are examined by the method of moments based on the volume–surface integral equations. Both the fluid field properties and the associated EM effects are analyzed for a real sphere–cone object that flies at a hypervelocity of 7650 m/s and at an altitude of 61 or 71 km. The impacts of the plasma sheath on the propagation, scattering, and radiation properties are discussed. The plasma sheath may block the transmission and radiation of radio waves for a wide range of frequencies, as the attenuation may exceed 20 dB. Also, the plasma sheath may influence the backscattering radar cross section to an extent of 20 dB. As the frequency increases, the effects tend to weaken and eventually may be ignored beyond 50 GHz. The simulation results are found in good agreement with available experimental data, which indicates that the proposed approach is reliable for predicting the level of radio blackout.