Numerical study of flow characteristics in a single-element Lean Direct Injection (LDI) combustion chamber

Studying the combustor flow field helps identify effective fuel and air mixing areas. The purpose of this paper is to investigate the structure of cold flow in a single-element Lean Direct Injection combustor. In studying and modeling of a turbine engine combustor, it is important to identify the areas of swirling, reversal and symmetry of the flow inside the chamber due to its influence on the rate of fuel and air mixing and also to study the reaction flow accurately. In this paper, the effect of operating pressure on the turbulent flow is studied. Since computational fluid dynamics are very time-consuming to solve the reacting flow problems, it is necessary to select the appropriate turbulence model that saves time with good accuracy. Comparing the computational results of the k-ɛ Realizable and Reynolds stress turbulence models (RSTM) and computational errors analysis, the maximum error was obtained for the Reynolds stress model of 31% and for the k-ɛ Realizable model of 37% compared to the experimental data. The difference between numerical results of turbulence models showed that the low-cost k-ɛ Realizable model is acceptable for the studied studies and can be used to model the reacting flow of an LDI combustor with highly swirl flow.