Exhaust nozzle for multi-tube detonative engines

Abstract

A nozzle for a detonative combustion engine, the engine having multiple combustor tubes, comprises a common plenum communicating with the combustor tubes. The common plenum combines separate exhaust streams from the combustor tubes into a compound subsonic exhaust stream. A compound flow throat communicates with the common plenum. The compound flow throat converts the compound subsonic exhaust stream into a compound sonic exhaust stream. The common plenum and compound flow throat cooperate to maintain a predetermined upstream combustor pressure regardless of down stream pressure exiting the expansion section. Optionally, an interface section is inserted between the plenum and the engine such that it communicates with the common plenum section and with outlets of the combustor tubes. The interface section is compartmentalized into flow passages with each flow passage having a cross-sectional area that increases from that of a particular nozzle intake port connected to a conductor tube exit. Additionally, an expansion section communicates with the outlet of the compound flow throat and has a diameter greater than the diameter of the compound flow throat. The expansion section converts the compound sonic exhaust stream into a compound supersonic exhaust stream thus expanding the exhaust stream to predetermined lower pressure.