Abstract: With gasoline as fuel and air as oxidizer, experiments were performed to investigate the propagation of back-pressure in an air-breathing pulse detonation engine (PDE) with inner diameter 60mm. The back-pressure was measured at different operation frequencies ranging from 10Hz to 30Hz. The experimental results show that the back-pressure approximately increases linearly with increasing frequency. The ratio that the time of pressure fluctuation to a cycle time increases with increasing frequency. The pressure oscillation has a maximum value with operation frequency of 20Hz. The numerical model was developed and the characteristic of formation and propagation of the back-pressure was numerically investigated. The simulation results confirm that the back-pressure is induced by the retonation wave. The experimental and numerical results agree well,indicating that the method of simulation can reasonably reflect the propagation process of back-pressure. 

Key words: Detonation; Engine; Back-pressure;Experiment; Numerical simulation

摘要： 以汽油为燃料,空气为氧化剂,在内径为60mm的吸气式脉冲爆震发动机上进行了反压传播规律实验研究。测量了10~30Hz频率范围内进气道内的反传压力。实验结果表明,进气道内的反压峰值随着工作频率的增加而增加,两者基本呈线性关系。随着工作频率的增加,压力波动的时间占每个工作循环时间的比例增加。压力脉动比在20Hz时达到最大。建立了数值模型,采用小能量点火及温度梯度自适应方法,计算得到了反压的形成及传播特性。计算结果印证了反压是由于回传爆震引起的。将计算结果与实验结果进行了比较,结果表明两者符合地较好。 

关键词: 爆震; 发动机; 反压; 实验; 数值模拟 