Coupled field numerical simulation of thermally loaded plasma coal gasification channels

Thermal plasma based system for fire support and stabilization in pulverized coal fired boiler, developed in Laboratory for Thermal Engineering and Energy, Institute of Nuclear Sciences "Vinca", Belgrade, is planed to be an alternative to existing oil burner's system at boiler A1 in the TPP Nikola Tesla in Obrenovac, Serbia. Assuming steady plasma-coal gasification process in the steady air-coal mixture channel flow, preliminary calculation predicted temperature of channel's inner wall at level higher then 700°C. This could induce thermal dilatations of thin-wall steel channel with rectangular cross­section that can remarkably affect air-coal mixture channel flow. In order to prevent occurrence of significant disturbances in the mean air-coal mixture flow, reconstructive operations on existing lower segments of burner's section are dane including replacement of one rectangular air-coal mixture channel with two channels having circular cross section. The aim of this work is to evaluate influence of thermally loaded channel dilatations on air-coal mixture flow in both cases.