Computational Study on the Effect of Vane Design in Enhancing the Mixing of Subsonic Jet and Sonic Jet

The purpose of this study is to numerically analyze the effect of vortex generators that are shaped like vanes in enhancing the mixing of subsonic and sonic jet and to determine the best design which yields maximum reduction in jet potential core length and minimum thrust loss at the nozzle exit.  Four different nozzle designs namely, models A, B, C and D are designed and compared with a base nozzle which is a plain circular nozzle without any vanes. The simulation is performed in ANSYS Fluent using the S-A turbulence model. The centerline pressure decay and radial pressure decay from models A to D are compared with that of the base nozzle to determine the ability of the vane to enhance the jet mixing characteristics. To evaluate the thrust loss, the total pressure at the exit plane of models A to D is measured and compared with that of the base nozzle. When comparing all the designs, it is observed that Model B produces the highest reduction in potential core length which is 66.4% at Mach no. 1 and Model D produces minimum total pressure loss which is 0.47% at Mach no. 0.4. In contrast to the conventional method, this design introduces a novel approach by placing the vanes parallel to the flow instead of the usual perpendicular arrangement. This unique configuration allows the vanes to redirect the flow rather than hinder it, resulting in a total pressure loss of less than 3%.