Richard J. Weber, John S. Mackay
Based on the assumption that shock-free internal burning is possible in a supersonic airstream, calculations are made for the performance of ramjets using supersonic combustion velocities. Diffusion of the air from the flight speed to a lower supersonic velocity is generally found to be desirable before the air enters the combustor. With a constant-area combustor, both maximum thrust and overall engine efficiency are achieved when sufficient heat is added to choke the flow at the combustor exit.
An Adobe Acrobat (PDF) file of the entire report: