Patent ID: 8528341

Claim:
A regenerative superheater system for a ramjet engine, comprising: (a) a superheater that includes a hot side and a cold side in thermal communication with each other; (b) a subsonic diffuser with a variable-geometry inlet and a subsonic nozzle with a variable-geometry exit in fluid communication with the hot side of the superheater and a combustion chamber of the ramjet engine, wherein combustion gas is bled from the combustion chamber through the subsonic diffuser inlet to the hot side of the superheater and released as exhaust through the subsonic nozzle; (c) a fluid reservoir in fluid communication with the cold side of the superheater, wherein fluid flows from the reservoir through internal passages in the cold side of the superheater, wherein the fluid gains thermal energy from the cold side of the superheater according to a temperature differential between the hot side and cold side of the superheater that is modulated by time-varying geometry of the subsonic diffuser inlet and subsonic nozzle; and (d) a delivery line that redirects the fluid upstream of the combustion chamber from the cold side of the superheater.