在翼型或机翼的风洞试验中,常用绊线或局部表面粗糙度来固定边界层转捩。本文研究了在零压力梯度条件下,这种人工扰动在风洞平板侧壁上的湍流边界层中的传递,并且发现扰动所引起的动量损失会保留在下游的边界层中。在零压力梯度下,这个局部的动量损失几乎是一个附加的常量,而逆压梯度则会扩大这种动量损失。不同直径的绊线在不同的位置对边界层扰动的大小是可以确定的。 In airfoil or wing wind tunnel tests, tripods or local surface roughness are often used to fix the boundary layer transitions. In this paper, we study the propagation of this artificial disturbance in the turbulent boundary layer on the side wall of a wind tunnel under zero pressure gradient and find that the momentum loss caused by the disturbance will be retained in the downstream boundary layer. At zero pressure gradient, the local momentum loss is almost an additional constant, while the reverse pressure gradient expands this momentum loss. Different diameter of the tripwire in different locations on the boundary layer of the size of the disturbance can be determined.