Design and Optimization of Divergent Angle of a CD Rocket Engine Nozzle Using Computational Fluid Dynamics

The present study involves the Computational Fluid Dynamics (CFD) analysis of a rocket engine nozzle to investigate the behaviour of supersonic flow at different divergent angles. A two-dimensional axi-symmetric model is employed, and the governing equations are solved using the finite-volume method in ANSYS FLUENT® software. The inlet boundary conditions are set based on available experimental data. The analysis focuses on studying the variations in key parameters such as the Mach number and static pressure. Additionally, the phenomenon of oblique shock is visualized, and the movement of the shock wave with respect to the divergent angle is observed. The results indicate that at a divergent angle of 8°, the shock wave is completely eliminated from the nozzle. Furthermore, it is observed that the Mach number shows an increasing trend as the divergent angle increases, suggesting the existence of an optimal divergent angle that minimizes shock-related instabilities and meets the thrust requirements for the rocket engine. The findings from this analysis provide valuable insights for the design and optimization of rocket engine nozzles, with potential applications in enhancing overall engine performance and stability.