Experimention And Numerical Simulation Of The Combustion Chamber Used In Top-Firing Hot Blast Stove

The combustion chamber is the core part of dome combustion hot stove. It affects the work of the hot stove and the quality of air.Therefore,it is very significant to research and understand its performances.So far,no reference about the experimental study of the combustion chamber used in dome combustion hot stove in the homeland was retrieved.In order to understand the situation of the gas flow and the flow distribution in the combustion chamber;a series of experiments have been carried out on two kinds of burners' model,respectively.The mixture situation of air and gas has been measured by energy spectrum analysis.Numerical simulation has been applied to the process in the combustion chamber.The outlets of coal gas and air were in the same row but gap arrangement in the modelⅠ.The centerline of the air vents was the same radial with the mixing chamber,and the angle of the gas vents into the mixing chamber was 25°angle.The experiment result of the modelⅠindicates that,under the non-premixed condition,the speed of vents was uneven when the air and the gas vents were in the same row layout.Air current was mostly concentrated in the center when the gas vents are DC type.Air current was mostly concentrated in the marginal when the gas vents were swirl type.Therefore the DC vents and the swirl vents should work in harmony.The new combustion chamber modelⅡhas been designed on the basis of analyzing the first combustion chamber's functions.Some characters have been measured on the new burner.The ring road of gas was above that of air. The air circuit and the coal gas circuit have the uniform distribution of two rows of every 12 vents respectively on the circumference.The centerline of the vents in the upper row is the same radial with mixing chamber,the angle of the vents in the lower row into the mixing chamber was 22°angle.The experiment result of the modelⅡindicated that,it is beneficial to mixture of air and gas and combustion stability when the air vents and the gas vents have a row of cyclone vents,respectively.The angle of the vents into the mixing chamber should be 22°angle.In addition,the gas gathering ring roads of the modelⅡwere external.Thickness between the ring road and the mixing chamber increases.Temperature difference of the unit thickness diminishes, heat stress of the fireproof material decreases.It was conducive to protecting the wall.It can be concluded from the model experiments that,the parameters such as vent's form,row number,vent's angle and vent's speed,have important effects on the commixture condition of the air and the coal gas in this kind of combustion chamber.The flow and the combustion procedure have been simulated by FLUENT software.It has simulated the field distribution of flow,concentration, temperature and pressure.The result of the numerical simulation agreed well with the result of experiments.