Numerical Simulation Of Two Pulse Detonation Engine

As a new concept propulsion system, pulse detonation engine which is based on detonation combustion is widely considered to be one of the most development meaning aeronautics and astronautics engines in the 21st Century. Efficient ignition is one of the key techniques. Two-Stage PDE is based on the shock wave focus periodic in the resonator cavity, which can explode the detonation directly. In this paper, Two-Stage PDE has been studied by using numerical simulations. The numerical method is coupled-explicit solver. The chemical reaction for the stoichiometric hydrogen-air mixture is modeled by one-step.The present paper involves three parts:Firstly, numerical simulation of non-reaction unsteady flow in a Two-Stage PDE resonator is studied in different reflectors including ellipsoid reflector, upright reflector parabolic reflector and conical reflector. On this basis, flow is simulated under varying the depth of the resonator (30mm-90mm) to investigate the influence of the depth of the resonator on the twice high pressure and high temperature region. The result shows the optimal depth of resonator can be determined in ellipsoid reflector and parabolic reflector, however, parameters of the second high pressure and high temperature region nearby point A in upright reflector and conical reflector vary with liner variation of the depth of the resonator.Secondly, on basis of the fuel pre fill in the resonator, the cases with different jet temperature and jet pressure are simulated. The results indicate the influence of the jet temperature and the jet pressure on detonation initiation. On this basis, the detonation explodes successful on the axial line by choosing the suitable jet parameters. Several refocusing phenomenon are captured associated with the development of the flow field. Further study shows that the detonation initiation position is on the vertex when the jet pressure is lower than one critical value.Thirdly, the multi-cycle working process of Two-Stage PDE is investigated by using the divergent section and the separation of fuel and jet flow. The result shows that the engine works steadily after one cycle. The detonation frequency is 1.9 KHz.