A computational and experimental study was conducted on nozzle geometries for rocket application rotating detonation engines (RDEs). Three geometries, including a nozzleless blunt body typically employed in RDE combustor hot-fire testing and two aerospike nozzles, were investigated. Simulations of the exhaust flow of a rotating high-frequency, high-pressure ratio wave based on rocket RDE test results were related to comparable constant-pressure conditions. Computational and experimental results showed the high momentum added by the highest-pressure detonation products influences the exhaust plume differently than a comparable steady flowfield fed by the same average product gas flow rate. In particular, the RDE exhaust flow tended to enhance entrainment on the nozzleless blunt body recirculation region and delay flow separation on nozzle expansion surfaces due to overexpansion compared to a constant-pressure engine. Results have important ramifications for isolating RDE combustor performance from nozzle effects and must be considered for future design of nozzle geometries to exploit the high-frequency, high-pressure ratio outflow of an RDE.

对用于火箭应用旋转爆震发动机（RDE）的喷嘴几何形状进行了计算和实验研究。研究了三种几何形状，包括通常在RDE燃烧器热试验中使用的无喷嘴钝体和两个气钉喷嘴。根据火箭RDE测试结果对旋转的高频高压比波的排气流进行仿真与可比较的恒压条件相关。计算和实验结果表明，与由相同平均产品气流量供入的可比稳定流场相比，由最高压力爆轰产物增加的高动量对排气羽流的影响不同。特别是，与恒压发动机相比，由于过膨胀，RDE排气流倾向于增强在无喷嘴钝体再循环区域上的夹带，并延迟喷嘴膨胀表面上的流分离。结果对于将RDE燃烧器性能与喷嘴效应隔离开来具有重要意义，并且在将来设计喷嘴几何形状以利用RDE的高频，高压比流出时必须考虑这些结果。