Discharge from a high-intensity millimeter wave beam and its application to propulsion

Abstract

Many experimental and numerical studies have been conducted to elucidate the fascinating physics of plasma formation and shock wave propagation during millimeter wave beam irradiation outputted from a high averagepower gyrotron. A microwave-rocket system for rocket launching was proposed as an engineering application using an intense millimeter wave beam. Flight demonstrations and thrust measurements were repeated while changing the ambient pressure, beam power density, beam profile, and vehicle shape. We reviewed reports of experimental and computational studies to assess information on plasma propagation and compressible fluid dynamics induced by the millimeter wave beam. Earlier experiments and simulations of rocket launching were also examined for this study.

Development of a Novel Launch System Microwave Rocket Powered by Millimeter-Wave Discharge

“…The comb-shaped filamentary structure was formed at much lower intensity than the breakdown threshold. Takahashi et al [46,47] proposed a numerical model considering compressibility of the ambient gas. Results showed that expansion behind a precursor shock wave enhances the effective field intensity to near the threshold in front of the plasma.…”

Computational Analysis of Plasma Evolution during High Power Millimeter Wave Breakdown using Mesh Refinement based Fluid Simulations

“…The model can address any general problem involving HPM breakdown at high pressures and can accurately reproduce the experimental observations [3]- [5], [7], [17]- [21]. Accurate simulation of this complex phenomenon will further help to understand the underlying physics for various applications in aerospace research [5], [6], high-speed combustion [22], microwave rockets [17], [23], [24], to study plasma shields that hamper the high power microwave transmission through the air [11] and will also help to realize the safe operation of high power microwave devices such as airfilled waveguides by suppressing the breakdown phenomenon using an external DC magnetic field [13].…”

Plasma propagation via radiation transfer in millimeter-wave discharge under subcritical condition

“…Experiments and numerical calculations have been carried out to study discharge phenomena caused by a high-power millimeter-wave irradiation [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. A millimeter-wave discharge can be applied to a microwave rocket (Fig.…”