Numerical Simulation And Engineering Application Of Single And Multiple Low NO_x Swirl Burners On The Same Floor

Under the new power system planning,the continuous improvement of new energy generator assembly capacity and grid connected capacity poses a great challenge to the stability and consumption capacity of China’s power grid.As the main power generation mode in China,coal-fired power generation must undertake the task of power grid peak regulation.Therefore,coal-fired power generation will still play an important role in the future.Among the coal-fired power generation modes,the swirl opposed co mbustion mode has better performance in reliable operation,reducing the deviation of heat receiving surface and ultra-low emission than the four corner tangential combustion mode,and has gradually been favored by supercritical and ultra supercritical coa l-fired units.OPCC low NO_x swirl burner is independently developed and designed by China.At present,it has been put into operation in many large swirl opposed boilers.However,the nozzle of medium frequency generator burner of coal-fired unit with OPCC low NO_x swirl burner is burnt out.So this paper takes the OPCC low NO_x swirl burner with burning loss of a swirl opposed boiler in Guangdong as the research object.Firstly,the 1:1 three-dimensional modeling and meshing of a single swirl burner are carried out based on Gambit platform.Secondly,used the control variable method to study the relationship between the air distribution mode and structural characteristics of a single swirl burner and the cold dynamic field.Based on the numerical simulation results of the cold dynamic field,carried out the multi condition comparative study on the relationship between the air distribution mode and structural characteristics of a single swirl burner and the hot combustion characteristics.At present,the numerical simulation of OPCC low NO_x swirl burner is nothing more than the numerical simulation of a single swirl burner or the whole furnace.However,a single swirl burner cannot consider the impact of other swirl burners when the project is actually put into operation;The numerical simulation of the whole furnace has the problem of over simplifying the structure of the swirl burner and there is a certain error with the engineering practice,therefore,this paper creatively carried out the numerical simulation of the cold and hot characteristics of multiple low NO_x Swirl Burners on the same floor.Similarly,Gambit platform is used to carry out 1:1 three-dimensional modeling and grid division.Based on the control variable method,carried out a multi condition comparative study on the relationship between air distribution mode and structural characteristics and cold dynamic field under the coupling of multiple low NO_x Swirl Burners on the same floor.After determining the structural characteristics of multiple Swirl Burners on the same floor based on the numerical simulation results of cold dynamic field,numerically simulated the relationship between air distribution mode and hot combustion characteristics of multiple low NO_x Swirl Burners on the same floor.Based on the numerical simulation method,this paper carries out the numerical simulation of OPCC low NO_x swirl burner.The conclusion of the numerical simulation results has been applied to the actual transformation of the project and achieved good transformation results.