Numerical And Experimental Investigation Of The Top-firing Hot-blast Stove Burner

The burner is the heating plant of the hot-blast stove, whose performance influences the service life and the air temperature of the hot-blast stove. The ceramic burner of top-firing hot-blast stove has many characters such as the short combustion flame, high theory combustion temperature, better combustion stability and the completeness of gas combustion, so it's widely used in the iron-making equipment. But the gas flow and gas combustion in the hot-blast stove are a complex process including turbulent flow, combustion, convection, radiation. Nowadays, the reasons for the lack of the systemic study and mature design experience are the flow field of the hot-blast stove and the basic combustion characteristic of the ceramic burner have not been understood. Based on this, the basic working characters of ceramic burner are investigated by the experiment and numerical simulation.In this paper, a three-dimensional model of hot-blast stove which the geometric similarity ratio is one sixth to the prototype is presented. Based on the governing equation and k -εturbulence model which suits to the gas flow in the top-firing hot-blast stove, the three-dimensional model is solved by FLUENT commercial software with SIMPLE algorithm. The flow fields of hot-blast stove are obtained. The numerical results also show the homogeneous characters of the combustion chamber outlet and the nozzle outlet, and the drift current is under control in the regenerator when flow control bricks are used in the gas loop.In addition, the current simulation methods of combustion are analyzed. Based on the diffusion combustion theory and P1 radiation model which suit to the gas combustion in the ceramic burner, the combustion process is simulated. The velocity distribution, temperature distribution and component distribution of the gas are obtained. By adjusting some parameters of the model, the numerical results can reflect the reality combustion process rightly.Further more, based on the similarity theory, an experimental model is built, and the cold state model experiment is carried out. The damping characters of the air loop, gas loop and model, and homogeneous character of the nozzle outlet are tested. By the improvement of the gas loop structure, the homogeneous rate of the model is highly increased. At last, the paper summarizes the subject, and some ideas are given for the coming investigation of the ceramic burner in the top-firing hot blast stove.