弯段半径对回流脉冲爆震燃烧室起爆特性影响

The Effect of Bend Section Radius on the Initiation Characteristics of a Reverse Flow Pulse DetonationCombustion Chamber

中文关键词:  爆震  脉冲爆震涡轴发动机  回流脉冲爆震燃烧室  弯段半径  起爆特性

英文关键词:detonation  pulse detonation turboshaft engine  reverse flow pulse detonation combustion chamber  radius of bend sec⁃ tion  initiation characteristics

中文摘要:

      针对应用于脉冲爆震涡轴发动机的回流脉冲爆震燃烧室的起爆特性，建立了数值仿真模型，搭建了相应的试验系统，对 模型进行了试验验证，使用校验过的模型进行了仿真计算，在相同的进、出口边界参数与点火频率条件下对比分析了不同弯段半 径对爆震波生成的影响规律。结果表明：存在较优的弯段半径范围（0.9~1.3倍管径），使得在限定尺寸范围内，在燃烧室内能形成 充分发展的爆震波。在弯段半径过小时，弯段内的高温区与高压区分离使得弯段内无法形成局部高温高压中心；在弯段半径过大 时，压缩波在弯段内的反射汇聚效应减弱，难以在弯段内形成有效的高压区。随着弯段半径的增大，爆震波形成位置与弯段出口 的距离先减小后增大，爆震燃烧室总的爆燃向爆震转变距离随着弯段半径的增大而增加。

英文摘要:

      The numerical simulation model and the corresponding experimental system were established for the study of the initiation characteristics of a reverse flow pulse detonation combustion chamber applied to a pulse detonation turboshaft engine, the model was experimentally verified, simulation calculations were conducted using the verified model, the influence of the different bend section radii on the generation of the detonation wave was analyzed under the same inlet and outlet boundary parameters and ignition frequency condition. The results show that there exists a better range of bend section radius (0.9-1.3 times of the pipe diameter), which allows the formation of a fully developed detonation wave in the combustion chamber within the limited size range. The high temperature zone and high pressure zone would separate and the local high temperature and high pressure centers would not be formed when the bend section radius was too small. The reflection and convergence effects of the compression waves in the bend section would decrease and the effective high-pressure zones in the bend section are difficult to form when the bend section radius is too large. With the increase of the bend section radius, the distance between the exit of the bend section and the formation position of the detonation wave decreases first and then increases. The total deflagration-to-detonation transition distance of the combustion chamber increases with the increase of the bend section radius.