局部扰动对平板边界层流动稳定性影响的研究

在壁面上构建局部扰动,数值研究不同特征的局部扰动对平板边界层流动稳定性影响的作用机理,进一步探讨壁面扰动的分布、类型、强度大小对三维扰动波在平板边界层流动中的非线性演化规律以及失稳机制的问题.确定什么样的局部扰动能使三维扰动波快速增长或者是什么样的局部扰动能对流动起抑制的作用,同时寻求在三维扰动波向下游发展过程中的传播方向会发生怎样的变化等.对该问题的深入研究,将使人们能深入理解认识平板边界层流动过程中的转捩发生、流动失稳及湍流形成的理论机制.

Numerical study on the effect of local disturbance on hydrodynamic stability of plate boundary layer

In this paper,local disturbances structure is designed on flat-panel wall,and the effect of differently characteristical local disturbances on hydrodynamic stability of plate boundary layer is numerically studied.Further,the distribution,type and intensity of local disturbance influence upon the nonlinear evolution and instability control of the three-dimensional disturbance waves in the plate boundary layer.The local disturbance structure could lead to the rapid or slow growth of 3-D disturbance wave.At the same time,the change of propagation direction of 3-D disturbance waves in the process of developing toward the downstream can be found.The study will enable people to understand the transition occurs,hydrodynamic instability and the formation mechanism of the turbulence in the plate boundary layer.