气体与液体两相连续旋转爆轰发动机爆轰波传播特性三维数值模拟研究

Three-dimensional Numerical Simulation on the Propagation Characteristics of Detonation Wave in Gas-liquid Two-phase Continuous Rotating Detonation Engine

为了研究气体与液体两相连续旋转爆轰波的传播特性,基于三维守恒元和求解元方法,在圆柱坐标系下采用带化学反应的气体与液体两相爆轰模型,对连续旋转爆轰发动机进行三维数值模拟。通过计算获得了爆轰波起爆及其稳定传播时的流场结构,分析了流场在燃烧室径向方向的变化以及发动机的推力性能,揭示了两相爆轰波的传播特性。研究结果表明:燃烧室内流场结构与文献[4]中的实验研究结果定性一致;由于环形燃烧室外壁面的收敛和内壁面的发散,爆轰强度沿着燃烧室的径向方向逐渐增强,实现了爆轰波的自持旋转传播;以汽油为燃料、富氧空气为氧化剂,在填充总压为0.2 MPa、总温为288.15 K、燃料液滴半径为25μm的条件下,连续旋转爆轰发动机所获得的平均推力约为880 N,爆轰波的传播频率约为4 390 Hz.

A gas-liquid two-phase detonation model with chemical reaction is established in cylindrical coordinates based on the conservation element and solution element method, and the three-dimensional numerical simulation of continuously rotating detonation engine is performed to investigate the propagation characteristics of gas-liquid two-phase continuously rotating detonation wave. The flow field structure and stable propagation of detonation wave at initial formation stage were obtained through the calculation. Meanwhile, the variation of flow field in the radial direction and the thrust performance are analyzed, and the propagation characteristics of two-phase detonation wave are revealed. The simulated results show that the flow field structure in the combustion chamber is consistent with the experimental results in Ref. [ 4 ]. Because of the convergence of outer wall and the divergence of inner wall, the detonation strength increa- ses along the radial direction of the combustion chamber. The self-sustaining rotating propagation of detonation wave is realized. When the injection pressure and injection temperature are 0.2 MPa and 288. 1.5 K, respectively, and the fuel droplet radius is 25 μm, the average thrust of the gasoline and oxy- gen-enriched air continuously rotating detonation engine is about 880 N, and the propagation frequency of detonation wave is about 4 390 Hz.