CFD Numerical Simulation Study On Operation Optimization And Energy Saving Of Internal Combustion Hot Blast Stove

In this thesis,an internal combustion hot blast stove of a steel plant is taken was the research object and was studied by using computational fluid dynamics(CFD)numerical simulation method.In the numerical simulations,a three-dimensional steady-state CFD model for the whole hot blast stove and a two-dimensional transient CFD model for a single channel of checker bricks in the regenerator of the hot blast stove were established.Then,the three-dimensional steady-state CFD simulation of the whole hot blast stove was combined with the two-dimensional transient CFD simulation of the single channel in checker bricks in the regenerator to realize highefficiency simulation calculations of the continuous and multi operation cycles(combustion period and blast period)of the hot blast stove.In the present research,firstly,the arrangement of checker bricks on the top of the regenerator of hot blast stove was reformed to improve the distribution of flue gas flow entering the regenerator during the combustion period,which was simulated by using the developed CFD models.According to the simulation results,the flow field,temperature field and concentration field on the top surface of the regenerator before and after the retrofit were compared and analyzed.In order to verify the accuracy and practicability of the model simulations,thermal data before and after the checker brick arrangement modification on the top surface of the regenerator in the steel plant were collected and compared with the simulation results to verify the validity of the simulation models.The simulation results are as follows:(1)The numerical simulation results show that the uniformity of flow distribution on the top surface of the regenerator of internal combustion hot blast stove was improved.The average temperature of the flue gas entering the regenerator during combustion period is 43 °C higher than that before retrofitting.(2)The results show that the average temperature of hot air obtained by blast furnace is 39 ° C higher than that before the retrofit after the layout of lattice brick on the top of the regenerator is improved.(3)Two dimensional unsteady CFD numerical simulation results of lattice brick single channel for heat transfer in regenerator of hot blast stove show that: before reconstruction,the top temperature of regenerator is relatively low,and the overall hot air temperature is relatively low during air supply period,and with the extension of air supply time,the air temperature drops greatly;after retrofit,the top temperature of regenerator is relatively high,and the overall hot air temperature is relatively high and stable during air supply period.(4)The CFD simulation results for the operation optimization of hot blast stove show that when the air consumption coefficient is close to 1.0,the combustion effect is the best,and the gas in the hot blast stove is basically completely burned.