旋转爆轰发动机的有效工作直径设计

采用单步化学反应模型，忽略黏性、热传导和扩散效应等对流动的影响，对流项采用5阶WENO格式进行离散，时间步进采用3阶精度的Runge-Kutta方法，对以H₂/Air为反应混合物的旋转爆轰发动机进行二维数值模拟，研究发动机有效工作的直径范围.研究表明:旋转爆轰发动机在特定条件下的临界直径为0.51倍的轴向长度l，只有大于临界直径时发动机才能正常工作；且随着直径增大，发动机推力、比冲、爆轰波高度和传播速度逐渐增大；通过Lagrange二次插值得到发动机直径上界的近似值为2.80l；以l作为长度单位，得到旋转爆轰发动机有效工作的直径范围为:0.51 ≤ L* ≤ 2.80. 

Design of Effective Working Diameters of Rotating Detonation Engine

One-step Arrhenius reaction model was used with no consideration of the effect of viscosity,heat transmission and diffusion on flow for mixtures of H2/Air to simulate twodimensional rotating detonation engine(RDE) to research on RDE's effective diameter range.The inviscid flux was discreted with fifth-order WENO scheme,and the time integration was performed with three-order Runge-Kutta Scheme.The results show that the critical diameter of RDE is 0.51l in specific conditions,where l refers to the axial length,only when the diameter is larger than the critical diameter can RDE work properly.As the diameter increases,the thrust,specific impulse,detonation wave height and the wave propagation velocity increase gradually.The upper limit of RDE's diameter is about 2.80l,which comes from Lagrange quadratic interpolation.The effective diameter range of RDE(taking l as the length unit) in this specific condition is 0.51≤L* ≤2.80.