The aim of the current article is to study the combustion characteristics of the liquid fuel (Jet-A) inside a gas turbine model combustor under different conditions of the inlet air and fuel. The two-phase flow of the air and liquid droplets is modeled with the two-way coupling in the Eulerian–Lagrangian approach. The steady flamelet and discrete ordinates models are implemented to model the combustion and radiative heat transfer, successively. The \({\text{NO}}_{\text{x}}\) modeling is done as a post-process using the finite rate model. The outcomes indicate that increasing the fuel spray velocity leads to an improvement in the combustion phenomenon in the primary region, a rise in the flame temperature, and finally, a growth in the amount of \({\text{NO}}_{\text{x}}\) produced. By decreasing the half angle of fuel injection by 10°, the maximum temperature inside the combustion chamber decreases by 43 K. An increase of \(26\text{\%}\) in the inlet air temperature (from \(373\) to \(473\text{ K}\) ) does not have a considerable effect on the species’ concentration distribution. However, with a \(54\text{\%}\) growth in the inlet air temperature, changes in the concentration distributions particularly in the concentration of \({\text{CO}}_{2}\) become noticeable. Enhancing the temperature of the inlet air causes a rise in the concentration of \(\text{NO}\) . The concentration of \(\text{NO}\) is highly dependent on the inlet air pressure, and a direct relationship has been observed between increasing the inlet air pressure and the amount of the \(\text{NO}\) produced.
