Abstract
The laminar-turbulent transition of a mixing layer induced by oscillating flat plates at an exit of a two-dimensional nozzle was experimentally investigated. The mixing layer was formed between the jet which issued from the nozzle and the surrounding quiescent fluid. The plates oscillated vertically in relation to the mean flow. The oscillation frequency was two orders of magnitude smaller than the fundamental frequency of the velocity fluctuation. The disturbance traveled downstream as the convective instability, though it was damped only far downstream. Fluctuating energy production and convection rates that contribute to the streamwise and normal fluctuating velocities became maximum at different streamwise stations. The stations did not correspond to the respective positions where the fluctuating velocity became maximum in the streamwise component, although it corresponded in the normal component.
