COMPUTATIONAL ANALYSIS OF SUPERSONIC JETS FROM RECTANGULAR NOZZLES

Abstract

A prominent field which is drawing much attention in recent times is the mixing characteristics of supersonic jet flows because of its wide ranging applications in Aero-engines. Unlike in subsonic flows, vanes or baffles could not be used for creating mixing in a supersonic flow. In the present study, the supersonic jet flow from a nozzle with rectangular cross section is analyzed using CFD Techniques. The primary cause of the non-uniform flow exiting the nozzle is due to cross-flow pressure gradients imposed on wall boundary layers. The cross-flow pressure gradients cause the boundary layer to roll up into counter-rotating vortex pairs on each of the four sides of the nozzle. These four vortex pairs produce significant non-uniformity in the nozzle exit flow. The nozzle is designed using CATIA design software and the computational analysis is done using ANSYS CFX software for different aspect ratios.