Aerodynamic Design and Numerical Simulation of Over-under Turbine-based Combined-cycle (TBCC) Inlet Mode Transition

A parameterized design method is established for mode transition of over-under TBCC inlet and the design variables are optimized by Multi-Island Gene Algorithm using auto-CFD solution. Dynamic overset grid technology is utilized tocontrol and simulate the coupled rotation of both the flow splitter and ramjet cowl of TBCC inlet. Mach number effects, time effects and rotating patterns of the splitter during TBCC mode transitionare studied systematically by unsteady simulation in contrast to quasi-steady numerical result,and which shows that all these factors have great influence on the dual-flowpathinlet throat performance as well as the aerodynamic characteristics with similar hysteresis effects.