Numerical simulation and parameter analysis of kerosene/oxygen combustion flame in a supersonic spray gun

The characteristics of supersonic flame, such as temperature and impact velocity, are crucial for assessing the performance of coating materials in a thermal barrier coatings (TBCs) service environment simulation device. A 2D supersonic spray gun (SSG) is modelled using the ANSYS software. Numerical simulations are performed to investigate kerosene/oxygen combustion and the influence of inlet parameters in a SSG. Comparison of the numerical simulation of the axial temperature with the experimental data, the standard k - ε turbulence model is selected for the analysis of the turbulent flow and the Eddy-Dissipation model (EDM) is chosen to analyze the combustion process. The results show that an increase in the total mass flow of kerosene/oxygen results in only a marginal rise in the overall flame temperature. The temperature can be maximized at a kerosene/oxygen mass flow rate mass flow ratio of 2.5, while a ratio of 3.5 proves to be the most suitable for application in practical testing situations. Furthermore, an increase in the oxygen inlet pressure significantly elevates the overall Mach number of the flame flow, extends the supersonic zone, and enlarges the pocket structures. Adjusting the contraction ratio of the convergent section in the supersonic spray gun can effectively optimize both the flame temperature and velocity.