Film cooling effectiveness enhancement using surface dielectric barrier discharge plasma actuator

The case presented here deals with the enhancement of film cooling effectiveness using plasma flow control. In this experimental study, a jet is injected from an elongated slot into a thermally uniform cross-flow. The influence of a surface plasma dielectric barrier discharge actuator on heat transfer downstream of the slot is investigated. 2D PIV and IR-thermography measurements are performed for three different blowing ratios of M = 0.4, 0.5 and 1. Results show that the effectiveness can be increased when the discharge is switched-on. Whatever the blowing ratio, the actuator induces a deflection of the jet flow towards the wall, increases its momentum and delays its diffusion in the cross-flow. The best results are obtained with a blowing ratio close to 0.5 and an steady actuation without any frequency modulation.