Research On Modeling And Simulation Of Supersonic Scramjet

In this thesis, modeling and simulation of hypersonic scramjet are studied in order to provide a scramjet model which is able to research on control theories and strategies of scramjet engine, this model hopefully substitute for CFD softwares for their limitations of computational complexity and time consuming, provides a basic for researching on control theories and strategies of scramjet engine.The external compression area and internal compression area are studied in order to design the inlet, supposed the flight altitude of vehicle H=23.9km, and mach number 5 as the design point. the possibility of the inlet model was validated by the simulation results; A scramjet combustion chamber model is built, and the results of flight experiment and simulation results were compared to validate the possibility and credible of the model.A quasi-steady analysis technique is used to studying the flowfield in the inlet,a start state judgment criterion was give according to the pressure rates of the lip and the second rampω1,, the throat and the lipω2: whenω1<2.5,ω2>1.5, the inlet start . the flowfield was simulated and studied when changing the mixing equivalence ratio, entrance mach number and the position of the fuel injectors, some conclusions are given:1) increasing the mixing equivalence ratio can enhance the pressure of the tailof combustion chamber, but reduce the burning rate when the combustion chamber isn't jammed; 2) increasing the entrance mach number extend the mixing length, go against enhancing the pressure of the tail of combustion chamber; 3)the position of the fuel injector should close to the entrance of the combustion chamber, and two point fuel injectors enhance the performance.