Modeling of turbulence, chemistry, and heat transfer of a rocket nozzle

Abstract

Calculating the composition of the combustion products serves as the starting point for the high-area ratio (HAR) rocket nozzle. The HAR rocket nozzle finds application in next-generation hypersonic vehicles and missiles. The gas dynamics, gas radiation, and turbulence-chemistry interactions (TCI) play a crucial role in simulations of hypersonic turbulent reactive flows through a rocket nozzle. The interaction of turbulence and chemistry leads to random species mixing and enhanced heat transfer. The k-omega shear stress transport (SST) model is employed to calculate the average flow fields. The eddy dissipation concept (EDC) with reduced chemistry is applied to capture the TCI in the nozzle. The spectral properties of H2O are calculated using the full spectrum k-distribution (FSK) model in conjunction with the first-order spherical harmonics method. The mass fractions of combustion products obtained from Particle Swarm Optimization (PSO) and Monte Carlo (MC) methods agree well with the Chemical Equilibrium with Applications (CEA) code. The flow fields obtained with the current solver are validated with the published experimental data. A significant rise and fall of 7–8% have been observed in the centerline flow properties when not including the TCI models in the flow solver. The centerline flow fields obtained with different discretization schemes are in good agreement. The radiative heat flux from the H2O species is more dominant than the convective.