Three-Dimensional Numerical Simulation Of Rotating Detonation Engine With Separate Supply Of Fuel And Oxidizer

Rotating detonation engine(RDE) is a new kind of engine based on detonation combustion. With respect to pulsed detonation engine, RDE have high thermal cycle efficiency and less pollution. what’s more, It has the advantages of operating continuously just with one initiation, which leads to a wide application prospect. The purpose of this thesis is to study operateing characteristics of RDE with separate supplyof fuel and oxidizer based on numerical simulations. The main conclusions are as follows:(1) To research the cold-flowing mixing effect of fuel and oxidant gases in the combustion of RDE. Based on the ideal gas assumptions, three dimensional Euler equations are solved by coupling with high-resolution upwind flux split scheme (AUSMPW+) and time using the four-step runge-kutta method. According to the numerical results, the cold-flowing mixing flow field characteristics of fuel and oxidant gases are described in detail. different injection schemes such as different fuel injection position, injection angle, and unilateral or bilateral injection and boundary conditions such as mass flow rate, back pressure, equivalence ratio effects on cold-flowing mixing effect and flow field. Mixing degree is used to quantitatively evaluate the gas-gas mixing extent. The results shows:as the injection position moves forward, the H2/Air mixing effect obviously improved. The change of the injection angle also has a great influence.the mixing effect is good in reverse injection. For the injection method through unilateral and bilateral injection holes, the mixing effect of injection with holes from double side is significantly better than the unilateral injection. In the given calculation condition, different calculation parameters was compared, as mass flow rate increased, mixing effectiveness gradually decreases. As back pressure increased, mixing effect gradually increased. The change of the equivalence ratio has a little influence. As equivalence ratio increased, the mixing effectiveness increases a little.(2) In order to study the operation process of RDE with separate supply of fuel and oxidizer. based on the ideal gas assumptions, three dimensional Euler equations with chemical reactions are solved by coupling with high-resolution upwind flux split scheme (AUSMPW+),7 species and 8 reaction kinetics model, and the transport processes such as thermal conduction, diffusion andviscosity were ignored. The flow field structure of RDE and the influence of fuel injection strategies on RDE characteristics were discussed in detail. results show that:the numerical method used in this article can simulate the flow field structure of the RDE effectively. In the given calculation condition, as the injection position moves forward, the RDE characteristics were obviously improved. But the change of the injection angle has a little influence. As the injection angle decreases, the RDE performance was gradually improved. The RDE performance with the double side injection method was much better than that with the unilateral injection. The RDE performance is proportional to the mixing effect. In the given calculation condition, as mass flow rate increased, engine propulsive performance obviously improved,detonation wave height showed an increase firstly but decreased. As back pressure increased, the average thrust,specific impulse based on mixtures and detonation wave height gradually decreases, the average propagation velocity of rotating detonation wave gradually increased. As equivalence ratio increased, the average thrust、specific impulse and the average propagation velocity of rotating detonation wave gradually increased,detonation wave height keep stable.