Design study and component tests on a subscale precooled turbojet engine for flight experiments

Components of the small scale precooled turbojet engine such as variable intake, air pre-cooler, core engine, ram combustor, and variable nozzle are designed and tested for flight experiments and high enthalpy wind tunnel tests. The engine is expected to be operative from lift-off to Mach 6 by applying the precooling system and using LH2 as a fuel. Length of the engine is 2 m. Hypersonic and supersonic wind tunnel experiments are conducted to acquire and improve the intake aerodynamic performances. Total pressure recovery of the intake is 0.22 at Mach 5. Variable intake with advanced composite material is designed to realize the intake without cooling under Mach 6 flight condition. The shape of the intake and the precooler is determined using FEM analysis. Mixed compression type compressor is designed by CFD analyses. Component test of the main combustor is performed using gas hydrogen. A variable mechanism and cooling mechanism of the rectangular nozzle is designed. After the wind tunnel and combustion tests of the engine components, total engine system is designed by 3 dimensional CAD. The weight of the engine satisfies the requirement of the flight test.