Comparative Analysis of Turbulence Models for Turbulent Non-premixed Combustion: A Hybrid Rocket Engine Case Study

The phenomenon of turbulent combustion in the range of high Reynolds numbers is complicated to model using standard averaging methods like RANS (Reynolds-averaged Navier-Stokes). In the presented research, an extensive comparative analysis of turbulence models used for modeling this type of phenomenon was carried out. The object of the study was a combustion chamber of a hybrid rocket engine with swirled oxidant injection and a divergent section at the end of the chamber to ensure better mixing of fuel and oxidant. As part of the study, a DDES (Delayed Detached Eddy Simulation) type simulation was performed, from which averaged flow fields were then created using the Favre averaging. The flow field thus created was compared in 2D RANS-type simulations using the most popular turbulence models in this type of analysis, such as \(k-\omega \) , \(k-\epsilon \) , hybrid models, and RSM (Reynolds stress equation model). Analyzing the results allows us to identify the limitations of simplified analyses and show which turbulence model is most effective for modeling turbulent combustion phenomena.