Author : Jamesha Ibrahim 1
Date of Publication :7th March 2015
Abstract: This paper deals with the optimization of slanted perforated tabs to enhance the mixing characteristics of subsonic and sonic axi-symmetric jets issuing from a convergent nozzle. Measurements of centerline axial velocity decay and radial velocity distribution were carried out. The effect of various perforation geometries such as circular, ellipse, square and triangular cross sections of 2mm equivalent diameter in the tab is analyzed and the corresponding area blockage are found to be 2.88%. In this paper the 3-D numerical simulations have been carried out using the commercial meshing tools and analysis software. The centerline velocity of the jet is found to decay at a faster rate for the tab with elliptical perforation geometry as compared to other geometries. Also the reduction in potential core length with elliptical perforation tab for the jet operated at Mach number of 0.4, 0.8 and 1 are found to be 43.8%, 49.5% and 50%.
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