09/18/2015
This is part of the magic that allows our system to operate. Most engines use mechanical means to preprocess the air, raising temperatures and pressures; this is not a possibility at speeds higher than Mach 3.5. The temperatures and velocities involved do not allow mechanical functions of compression as the flow would drop under the speed of sound, raising entropy, and decreasing work that can be extracted from the flow.
The solution is hidden in the air itself:
When in a supersonic flow, the compressible fluid (Yes, at high speeds air is a fluid - not a gas) stagnates on leading edges, causing shock waves to build up.
Taking advantage of these waves through body design allows the pre-processing of oncoming flow, bringing a hypersonic flow down to supersonic speeds, compressing, and directing parallel to the combustion chamber, eliminating the need for compressors or other moving parts. This allows the entire combustion chamber to remain isentropic, allowing supersonic gas to expand in a post cowl - trading temperature for pressure, and pressure for force.
This way a M3.5 flow can exit the rear cowl at speeds of M9 with minimal fuel being used.
Several designs exist that use a series of shock waves, and we are developing a dynamic system that uses movable planar surfaces to achieve higher pre-processing efficiency than a static body design, also allowing the system to perform as a rocket.
