COMPARATIVE STUDY OF SUPERSONIC NOZZLES

Abstract

In this experiment, comparative flow analysis of two different nozzles has been performed. The analysis has been performed according to the shape of the nozzles by keeping the same input parameters. The experiment has been carried out in two preliminary steps. First one includes modeling and CFD analysis and the later part is about comparing their different properties. For this analysis, two dimensional axisymmetric nozzle geometries were drawn in Solid Works and CFD analysis is done using Fluent. The basic difference between these two nozzle geometries is their outlet divergence angle, whereas the inlet cross-sectional area, throat cross-sectional area and nozzle length are exactly same. These two nozzle geometries were drawn having outlet divergence angle 10° and 20° respectively. Velocity, pressure and temperature distribution on both nozzles have been studied to take the final decision. From analysis, it is clearly observed that the nozzle having outlet divergence angle 20° gives higher exit velocity with Mach number of 5.62 whereas the nozzle with outlet divergence angle 10° gives an exit velocity with Mach number of 4.31. Besides, lower temperature distribution and lower pressure distribution were observed in the nozzle with outlet divergence angle 20° throughout the expansion zone and nozzle with outlet divergence angle 10° exhibits higher temperature and pressure throughout the expansion zone. As the nozzle with divergence angle 20° gives higher exit velocity, it is the better one between these two nozzles.