Experimental Investigation on Vortex Generator's Distance From Film Cooling Hole

Abstract

The effects of vortex generator distance from film cooling holes on increasing gas turbine blade film cooling efficiency have been studied experimentally. The technique of infrared (IR) thermography has been implemented to study the temperature field. The diameter of the film cooling hole and the crossflow velocity define the Reynolds number, which is fixed at 2369. There are now three different jets for crossflow blowing ratio adjustments: 0.5, 1.0, and 1.5. Three different vortex generator distances from the film cooling hole have been studied experimentally to increase the gas turbine blade film cooling efficiency. It has been shown that the lowest distance between vortex generator distance and film cooling hole yields better film cooling efficiency. Overall, the delta winglet pair with the lowest distance between vortex generator distance and film cooling hole outperforms the higher distance because of the generation of secondary longitudinal vortices that completely destroy counter-rotating vortex structures because their rotational tendency is opposite to that of the counter-rotating vortex pair (CRVP).