Numerical Simulation On Flow And Combustion Process In Riser Square Box Type Atmospheric Furnace

Square box type atmospheric heating furnace has the characteristics of large thermal power and high capacity.Compared with traditional cylindrical furnace,square box type furnace was suitable to meet the need of large-scale industrial production in the future.In the current literature,the study of square box furnace was relatively small.Therefore,the systematic numerical simulation research on square box furnace was of great significance to development of petrochemical industry.Numerical simulation research was carried out on the velocity distribution,temperature distribution,flame shape,composition distribution and tube temperature distribution on the combustion and tube coupled heat transfer of the square box type atmospheric furnace.The simulation results were close to the actual operating data by comparing them and the calculation model was proved to be reliable.Detailed simulation was done about the impacts of different excess air coefficient,air distribution proportion and fuel components on combustion process in furnace,determines the optimum excess air coefficient and air distribution ratio and obtains the influence of different fuel composition on the heating furnace combustion conditions.When the secondary air ratio was controlled within 0.7-0.75 and the excess air coefficient was controlled at 1.05,the combustion of the furnace was the best.Choosing the appropriate excess air coefficient and the air distribution proportion could guarantee the normal operation of the furnace and improve the working efficiency of the heating furnace.This has certain reference significance for the operation of the heating furnace.Detailed simulation was done about the impacts of the burner nozzle diameter and angle on the fuel combustion.This has certain reference significance for the optimization of burner structure.The results showed that the heat efficiency of the furnace was highest when the diameter was 3.5 mm.The three-dimensional geometrical model of the full-size heating furnace with tube was constructed using structured grids without any simplification.Numerical simulation research was carried out on the combustion and tube coupled heat transfer within the industrial scale of heating furnace in detail by partition coupled heat transfer calculation.