Numerical Simulation On The Combustion Process Of A New-type Pulverized-coal Burner

The paces of study on a new-type burner have never stopped. That makes the test of a new-type burner's performance very important, and the numerical simulation is one of the most valuable test methods. Based on a pilot-scale furnace, the combustion characteristic of a new-type pulverized-coal burner is simulated in three-dimension using the numerical simulation method.The method and model which be used in simulating the combustion process have been summarized in this thesis. The FLUENT software is used to simulate the flow, heat transfer, combustion process in the boiler.In the calculating course, the Realizablek -εdouble equations model is used to simulate the turbulence flow, the Lagrangian particle random trajectory model is used to simulate the two phase turbulence flow; the P1 radiation model is used to simulate the radiation heat transfer, the Mixture-Fraction/PDF is adopted to simulate the gas phase turbulence burning, and spread–power control burning model is adopted to simulate the coke combustion.At the same time, the cold-air aerodynamic field and the combustion characteristic in thermal state has been simulated in this thesis under different swirling intensity. The adaptability of the new-type pulverized-coal burner to different coal is also been studied.Though the comparison and analyze of the simulation, it has a good flow field when the swirling intensity of the secondary air is 1.27, 1.43. The greater the swirling intensity of the primary air, the shorter the distance of ignition is. It has been proved the adaptability of the new-type burner to different coal is very strong. The results simulated above offer the extremely theoretical guidance for the actual experiment.