Shear stresses in turbulent pulsating channel flow

摘要

An experimental study of the structure of a pulsating air flow through a smooth channel was carried out. The flow pulsations were artificially imposed onto the main flow through periodic blockage of channel outlet cross section. A method for determining the additional shear stresses due to the imposed flow pulsations is proposed. The essence of the method consists in the determination of the shear stresses based on the revealed dynamics of the flow velocity field, whose measurements were carried out by the optical method from the results of digital video recording of the flow pattern. Profiles of velocities, accelerations, and additional shear stresses during a period of imposed flow pulsations were obtained.