Thrust Augmentation of Solid Rocket Motors Using Beamed Microwave Energy

摘要

A method for augmenting the thrust of a solid rocket motor by coupling beamed microwave energy to aluminanparticles in the diverging section of a nozzle is analyzed.Coupling ofmicrowave radiationwithmicron-sized aluminanparticles increases the particle temperature. The main mechanism of thrust increase is expected to be gas–particlencollisions that transfer the increased energy of particles to kinetic energy of the expanding gas. A dynamic power-ngeneration and beaming scheme has been designed to produce 1.0 GWof power at a launch vehicle throughout thenfirst 50 kmof its ascent trajectory.Microwave coupling to alumina particles has been investigated experimentally. Antwo-phase, two-way coupled numerical model has also been developed to assess the increase in propulsivenperformance. The developed numerical capability has been used to calculate nozzle flowfields for two different solidnrocket motors with and without the addition of beamed microwave radiation. High gas density and fast collisionalnrelaxation result in the efficient transfer ofmicrowave energy to the kinetic energy of the flow.The total thrust in bothncases was found to increase by approximately 0.5%for a 100 = 2nmicrowave beamand by 6%for a 1 = 2nbeam.