Performance Evaluation of Hypersonic Pre-Cooled Turbojet Engine

Abstract

Pre-cooled turbojet engine is investigated to realize Mach 5 class hypersonic transport aircraft. The engine has been demonstrated under sea level static and Mach 2 flight conditions using hydrogen as fuel. In this study, Mach 4 propulsion wind tunnel test is performed and the performance of air intake, pre-cooler, core engine and exhaust nozzle are obtained. Liquid nitrogen is supplied to the pre-cooler as a coolant in place of liquid hydrogen. Gaseous hydrogen is supplied to the main burner to drive the turbine with the combustion gas. A protective screen is placed in front of the pre-cooler to prevent damages of it from high-speed particles. Bypass door is placed in front of the core engine to start the mixed compression air intake at low speed operation of the core engine. As a result, the engine performance data is obtained without any damage of pre-cooler. Air intake is started by the effect of bypass door at low speed operation of the core engine.