Numerical simulation of injection schemes in scramjet of RBCC engine

In order to make ejector mode, ramjet mode and scramjet mode operate in a single flowpath, validate the adaptability in multi-modes, and obtain good combustion performance, the effect of variations of the position of fuel injection on the combustion performance of the existing two dimensional (2D) engine was carried out by the numerical simulation involving three-steps reduced chemical kinetic model. Results show that with fuel-pylon injection, the reliable ignition and steady combustion of the RBCC engine in supersonic flow can be achieved by using the strut-rocket as the way of ignition source and flame stabilization; based on the fuel-pylon injection, better combustion efficiency and engine performance can be achieved with assistance of strut and isolator injection, in which the inner thrust is 1.35 times compared with the way of fuel-pylon injection and strut injection; the shock trains moves upstream further with more quantity of fuel injected in isolator, which will have impact on operation performance of the engine.