Numerical Investigation of Combustion/Shock-train Interactions in a Dual-Mode Scramjet Engine

Abstract

A high-resolution numerical study is carried out to investigate the transient process of the combustion and the shock-train developments in an ethylene-fueled directconnect dual-mode scramjet combustor. The transient simulation begins with the supersonic air flow development followed by fuel injection. Air-throttling is then applied at the expansion part of the combustor to provide mass addition to block the flow to subsonic speed. The ignition occurs several milliseconds later when the fuel and air are mixed sufficiently. The pressure build up by the combustion leads to the shock train formation in the isolator section that advances to the exit of the intake nozzle. Then, the air-throttling is deactivated and the exhaust process begins and the situation before the air-throttling is restored. Present simulation shows the detailed processes in the dual-mode scramjet combustor for better understanding of the operation regimes and characteristics.