Experimental Investigation of Innovative Vortex Generators in the Mixing Enhancement of Subsonic Jets

Abstract

Jet mixing becomes necessary for its wide range of applications from household appliances to modern high technology rockets. Various researchers have studied the enhancement of jet mixing and concluded that the most effective jet mixing is due to the engagement of a vortex generator at the exit plane of the nozzle, thereby creating vortices of different sizes to enhance the mixing. To intensify the jet mixing, two similar innovative vortex generators with a total blockage ratio of 3.5% are placed diametrically opposite locations of the convergent nozzle. The Aspect Ratio of the convergent nozzle is 1. A numerical investigation is carried out to assess the effectiveness of the vortex generator for Mach numbers of 0.4, 0.5, 0.6, 0.7 and 0.8. The centerline Pitot pressure decay was calculated and found to exhibit the core length reduction due to the introduction of the Vortex generator. To measure the effectiveness of the jet mixing using vortex generators, the results are compared with the uncontrolled jet.