脉冲爆轰发动机噪声的近远场传播研究

摘要

To study the propagation characteristics of detonation noise for pulse detonation engines(PDE),detonation noise in near-field was analyzed.A theory model was set up and the PDE detonation noise was calculated in this paper.Parameters of static pressure,total pressure and temperature were obtained by using the space-time conservation element and solution element method (CE/SE).And on this basis,PDE pressure distribution in near-field was obtained by using large eddy simulation,and the far field sound pressure were predicted too.The results showed that:when the distance was less than the reference radius, PDE detonation noise amplitude was proportional to the radial distance power of -3;when the distance was greater than the ref-erence radius,PDE detonation noise amplitude was proportional to the radial distance power of -1.The results were of great significance for studying the mechanism of detonation noise and control method.%为探索脉冲爆轰发动机（PDE）的爆轰噪声传播特性，对爆轰噪声进行分析，建立了理论模型并进行数值仿真。通过CE／SE 方法计算得到 PDE 管口静压、总压及总温随时间的变化曲线，在此基础上，利用大涡模拟得到了 PDE 近场区域的压力分布，并进一步对远场声压进行了预测。仿真结果表明：当轴向距离小于参考半径时，PDE 噪声以1／r3衰减；当轴向距离大于参考半径时，PDE 噪声以1／r 衰减。该结果对研究 PDE 噪声的形成及控制方法具有指导意义。