DefinePK

Abstract

Nozzles are the important part of propellers generating the thrust and enabling the rockets to move in a  forward direction. However, their efficient design is imperative to enhance the thrust force and to reduce fuel consumption. Therefore, the aim of this study is to conduct a comparative study of different convergent section
angles to evaluate the maximum thrust force of a supersonic nozzle. Computational fluid dynamic (CFD) simulation is performed with different convergent section angles ranging from 42 ° to 24° by maintaining the same pressure ratio and operating conditions. In addition, the numerical simulation is performed with different working fluids such as air, carbon dioxide, and carbon monoxide. Furthermore, the effect of inlet temperature on Mac h number is also analysed. The numerical simulation is performed on an unstructured grid. Meanwhile, the simulation is carried out on a 2D axisymmetric density - based coupled solver with a viscous k-Omega SST turbulence model. The results are validated with previous experimental work and found good agreement with 2.6 percent error. The study revealed that decreasing the convergent angle up to 27° has a favourable effect, and a 1.6 percent increase in thrust force was estimated. Additionally, CO₂ was considered the best working gas with the highest thrust performance, preceded by air, nitrogen, and CO. Furthermore, the inlet temperature has a significant effect on the nozzle Mach number. The findings of this study may be used to design efficient jet engines and rockets.