A plausible non-thermal plasma effect on shock waves

Summary form only given, as follows. Shock waves have been the main obstacle for the development of supersonic/hypersonic vehicle. The very high wave drag associated with shock wave formation around a vehicle imposes restrictive vehicle shape requirements, which limit the flexibility of the vehicle design. Moreover, shock waves formed around the supersonic/hypersonic vehicle have the side effect of producing sonic booms on the ground. Introducing an energy source at somewhere upstream of the object to the supersonic incoming flow, the gas heating results in a, local reduction of Mach number that in turn causes the shock to move upstream. The usually strong bow shock front is then replaced by a weaker oblique shock with significantly lower wave drag. However this process requires a large power density to significantly elevate the gas temperature. In this work, a plausible physical mechanism explaining the observed nonthermal plasma effect on shock waves is presented. Analysis shows that a symmetrically distributed plasma spike in front of the shock can effectively deflect the incoming flow symmetrically It is the increase of the deflection angle of the flow that modifies the shock wave structure.