Opposition control of turbulent spots

Opposition control of artificially initiated turbulent spots in a laminar boundary layer was carried out low-turbulence wind tunnel with the aim to delay transition turbulence by modifying structure within spots. The timing and duration control, which using wall-normal jets from spanwise slot, were pre-determined based on baseline measurements transitional layer. results indicated that high-speed region cancelled opposition replaced carpet low-speed fluid. application variable-interval time-averaging technique velocity fluctuation signals demonstrated reduction both burst intensity spots, but frequency increased.