The flow of products through the aft-end of a detonation combustor is intrinsically unsteady, ultimately resulting in periodic and nonuniform flow parameters at the exit plane of a rotating detonation combustor. Therefore, the integrated design of the nozzle and combustion chamber is an important challenge in rotating detonation engines (RDEs). This paper describes a thorough three-dimensional numerical simulation of a hydrogen–air rotating detonation combustor with/without an aerospike nozzle and investigates the nozzle flow without a combustor. The simulation results allow us to analyze the coupling characteristics of the rotating detonation combustor and the aerospike nozzle. The new features of the shock wave dynamics and expansion characteristics in the nozzle with/without an integrated RDE combustor are compared. For the same rotating detonation combustor exit, the propagation mode of the detonation wave and backpressure in the RDE combustor exit are affected by the aerospike nozzle. The intensity of the shock wave and the angle with respect to the direction of the air flow are lower with the aerospike nozzle than in the nozzleless model, which is consistent with the effect of backpressure increase on the shock dynamics. Regardless of whether the nozzle is connected to the combustor, the nozzle affects the dynamic alternation of the design point state to over-expansion and under-expansion along the circumferential direction. The shock wave intensity and total pressure recovery inside the nozzle with the combustor are slightly stronger than those in the nozzle without the combustor. Consequently, the thrust and total pressure recovery of the nozzle integrated with the RDE combustor are enhanced by 7% and 5.6%, respectively. Thus, decoupling the nozzle from the rotating detonation combustor is feasible for testing the design performance of the unsteady nozzle.

通过爆震燃烧器后端的产品流本质上是不稳定的，最终导致旋转爆震燃烧器出口平面处的周期性和非均匀流动参数。因此，喷嘴和燃烧室的一体化设计是旋转爆震发动机（RDE）的一个重要挑战。本文描述了带/不带气钉喷嘴的氢-空气旋转爆震燃烧器的全面三维数值模拟，并研究了不带燃烧器的喷嘴流动。仿真结果使我们能够分析旋转爆震燃烧器和气钉喷嘴的耦合特性。比较了带/不带集成 RDE 燃烧器的喷嘴的冲击波动力学和膨胀特性的新特征。对于相同的旋转爆震燃烧室出口，RDE燃烧室出口的爆震波和背压的传播方式受气钉喷嘴的影响。与无喷嘴模型相比，使用 Aerospike 喷嘴的冲击波强度和相对于气流方向的角度较低，这与背压增加对冲击动力学的影响一致。无论喷嘴是否与燃烧器连接，喷嘴都会影响设计点状态沿圆周方向的过膨胀和欠膨胀的动态交替。带燃烧器的喷嘴内部的冲击波强度和总压力恢复比不带燃烧器的喷嘴略强。最后，与 RDE 燃烧器集成的喷嘴的推力和总压力恢复分别提高了 7% 和 5.6%。因此，将喷嘴与旋转爆震燃烧器解耦对于测试非稳态喷嘴的设计性能是可行的。