Abstract. Low-temperature vortex combustion numerical simulation was performed using FIRE-3D software. Low-temperature vortex combustion aerodynamic and heat-andmass transfer versus coal dust size range characteristic were analysed. The results are presented in graphical form. P-49 Nazarovo station steam generator model was created. The results of the numerical modelling are suitable for coal dust size range effect on lowtemperature vortex combustion analysis.