Large eddy simulation investigation of the effect of radiative heat transfer on the ignition progress in a model combustor

•The TF model based on FLUENT undergoes secondary development. By loading UDFs, the DTF model is applied on FLUENT to simulate turbulent combustion.•LES-DTF method coupled with the skeletal mechanism of kerosene is used to investigate the influence in ignition process under low-temperature inlet.•The key factors that influence the ignition process in the cold flow field are analyzed.•The reasons why low-temperature inlet and high oil gas ratio affect the ignition process are discussed. Radiation significantly influences turbulent combustion. This paper investigates the impact of radiative heat transfer on the ignition process in a multi-staged model combustor. The ignition process is simulated both without and with consideration of radiation. Large Eddy Simulations based on the Euler-Lagrange description of the liquid spray and the Dynamic Thickened Flame model coupled with a skeletal chemical reaction mechanism are employed. The Weighted Sum of Gray Gases method are employed to solve the spectral properties and the Discrete Ordinates method is employed to solve the radiative transfer equation. The results indicate that radiative heat transfer influences the flame structure during the ignition process. In the flame propagation phase, both the total heat transfer and the exit average temperature are higher, with the radiative heat transfer during ignition being less than 15% of the total heat transfer. During the kernel generation phase, radiative heat transfer leads to a 7.24% increase in the maximum temperature of the flame kernel, a 7.74% expansion of the flame surface area, and outward movement of the position of the maximum heat release rate. Additionally, the ignition delay time extends by 14.91%. In the flame propagation phase, the flame transfers heat to the mixed gas and droplets near the flame surface through radiation, promoting flame spread.