Energy Deposition Techniques to Improve Scramjet Performance

The proposed program will explore the deposition of energy in a scramjet inlet to (re)start supersonic/hypersonic flow, without any moving parts or actuators. The resulting expansion and heating can prompt flow-control that favors inlet-(re)starting. The approach can integrate well with other supersonic/hypersonic flow-control applications, which will further be considered in the course of the program. BENEFIT: The benefits of this non-mechanical approach to scramjet inlet (re)starting will be low-risk operation, with nearly instantaneous re-start and fast recovery of the starting system. The anticipated weight penalty is much less than mechanical systems, and there is no associated loss of efficiency when flying at the design point. Many of the currently proposed approaches involve mechanical mechanisms that involve risk and maintenance, with the alternative being to overbuild the powerplant to force the flow through the throat before throttling down to the desired operating conditions. If this technique provides the anticipated non-mechanical solution, a large weight constraint will be lifted, resulting in the possibility of closing the design on a single-stage (to orbit) hypersonic vehicle.  This is of great interest to the large contractors as potential industrial partners. Depositing energy in the upstream flow can also enhance the combustion process through pre-excitation and heating of the air. This has the potential to employ the necessary hardware to optimize the combustion cycle during general operation.