COMPARATIVE ANALYSIS OF CFD TURBULENCE MODEL FOR A SUPERSONIC NOZZLE AT DIFFERENT CONICAL ANGLE

Abstract: A rocket nozzle is a mechanical device which was to design the control of rate of flow, speed, direction and pressure of stream that exhaust through it. There are various types of rocket nozzles which were used depending upon the mission of the rocket. This analysis was over a convergent divergent rocket nozzle. The objectives are to measure the pressure and Mach number variation within convergent divergent rocket nozzle with different divergent angle. In this paper computational Fluid Dynamics (CFD) Analysis of various performance parameters like static pressure and the Mach number are studied in detail for a rocket nozzle from Inlet to exit by using Ansys Fluent software. From the public literature survey the geometry of the co-ordinates are taken. A two- dimensional convergent divergent nozzle model is used for the analysis and the governing equations were solved using the finite-volume method in ANSYS FLUENT software. The divergent angles used for analysis were 5°, 9°, 11° 15°,20°.The boundary conditions of the nozzle are specified based on literatures revised. The created nozzle geometry is solid works then exported to ANSYS AUTODYN for meshing. The meshed geometry was imported in the analysis software package FLUENT. The fluid inside the nozzle subject to supersonic speed in standard k-epsilon model and spalart allmaras pressure, density, viscosity along with other details were noted down. The pressure contour and Mach number contour particular nozzle models were plotted. The simulation performed in steady state condition, where oblique shock occurred at flow velocity greater than Mach number 1 was captured. After the simulation the results revealed that the divergence angle varies the Mach number and other performance parameters also varies. The divergent angle increases for each simulation and the results were compared in order to suggest the better nozzle model.