Simulation Of Soot Generation In Pulverized Coal Boiler Based On TRI And Analysis Of The Influence Of Pulverized Coal Particles On Radiation

When a large pulverized coal boiler is burning,the turbulent radiation interaction（TRI）will affect the temperature field,which in turn affects the generation of soot and NO_X and other pollutants.Taking a 300MW four-corner tangentially rounded pulverized coal boiler in a power plant as the research object,numerical simulation methods are used to analyze the combustion temperature field of the boiler furnace under the interaction of turbulent radiation,and its influence on soot generation and NO_X,and study the effects of temperature turbulence and particles on radiation heat transfer and pollutant generation.According to the design parameters and structural dimensions of the HG1025/17.5-HM300MW subcritical natural circulation drum boiler,pulverized coal combustion under the interaction of turbulent radiation.Use ICEM software to mesh the boiler body,and use numerical simulation software Fluent to numerically simulate the influence of pulverized coal combustion in the furnace,Soot,NO_X generation,particles and temperature turbulence and particles on radiation heat transfer under the action of TRI.The user-defined scalar method（UDF）and the group balance model（PBM）are used to numerically simulate the turbulent radiation interaction of power plant boilers.Define and solve the root mean square of temperature fluctuations,then use the UDF function of the Fluent software to modify the radiation source term in the radiation transfer equation to include the turbulent radiation fluctuation term,and then use the software’s own PBM model to complete the turbulent radiation interaction Simulation of the role.The simulation study of pulverized coal combustion with or without turbulent radiation interaction under different load conditions.Numerical simulation of the combustion process of pulverized coal with or without TRI under three load conditions of 140MW,210MW,and300MW.The results show that:in general,as the boiler load decreases,the temperature decreases and the NOx content decreases significantly,but it does not have much influence on the O₂ and CO content in the furnace.The combustion temperature of pulverized coal under the action of TRI is lower under the same load.The average temperature drops by 57K,51K and54K,respectively.The pollutant emissions are relatively reduced,and the content of O₂ and CO does not change much.On 140MW with or without TRI,the formation of Soot,the effect of temperature fluctuation,and the effect of coal particles on it.The results show that after considering the effect of TRI,the average concentration of soot increases due to the increase of temperature,which increases by 1.524g/m³ at 15m,which proves that its temperature is negatively correlated with soot formation.At the same time,after considering the effect of TRI,the soot has a wider range of influence and the aggregation effect is more concentrated.The residence time of pulverized coal is longer,and the turbulent radiation interaction caused by its temperature fluctuation increases the radiation heat transfer of the furnace flame.At the same time,the scattering effect of burning particles makes the distribution of turbulent kinetic energy in the furnace more diffuse,the number of turbulent kinetic energy is larger,the number of particles increases relatively,the opacity of each section of the furnace increases,and the background radiation of the furnace increases.In summary,the turbulent pulsation of particles in TRI must not ignore.