基于扰动方程的超音速轴对称射流马赫波辐射研究

发布时间：2018-04-13 13:32

  本文选题：非线性扰动方程 + 线性稳定性　； 参考：《计算力学学报》2017年02期

【摘要】：超音速不稳定波是导致剪切流失稳和转捩的主要不稳定模态,这种模态以马赫波的形式辐射到远场,从而产生强烈的声场。采用线性稳定性理论和非线性扰动方程(NLDE)分析,计算超音速轴对称射流不稳定波的扰动演化(Ma=2.1),对马赫波辐射进行研究,包括马赫波辐射方向、辐射源位置,以及随斯特劳哈尔数的变化情况。研究结果表明,在超音速轴对称射流中,马赫波沿固定方向辐射向远方,不稳定波相位沿另一方向传播,这两个方向相互正交;马赫波辐射源位置位于不稳定波压力幅值最大处;斯特劳哈尔数St越大,马赫波辐射的能力越强,辐射区域越集中。
[Abstract]:Supersonic unstable waves are the main unstable modes leading to shear loss stability and transition, which radiate to the far field in the form of Mahh waves, thus producing a strong sound field.By using the linear stability theory and the nonlinear perturbation equation (NLDED), the perturbation evolution of the unstable waves of the supersonic axisymmetric jet is calculated. The radiation of the Mahh wave is studied, including the direction of the radiation and the location of the radiation source.And with the change of Straugher number.The results show that in the supersonic axisymmetric jet, the Maher wave radiates far along the fixed direction and the phase of the unstable wave propagates in the other direction. The two directions are orthogonal to each other.The location of the Mach wave radiation source is located at the maximum value of the unstable wave pressure, and the greater the Strauher number St, the stronger the ability of the Maher wave radiation and the more concentrated the radiation region.
【作者单位】： 天津大学机械工程学院力学系;
【基金】：国家自然科学基金重点项目(11332007);国家自然科学基金(10972156)资助项目
【分类号】：O358
，

本文编号：1744737