Numerical Simulation Of High Temperature Air Oil-Free Ignition Technology And NO_x Formation

Our country is abundant in coal and deficient in oil, the short supply of oil turns to be a serious problem. High temperature air oil-free ignition is a new-style coal particle burning technology, which can be used in coal-fired boilers start-up or low load in thermal power plant and save a lot of oil.Numerical simulation method is employed in this thesis to investigate high temperature air ignited burner and coal-fired boiler using this type of burner. First, design six different pulverized coal concentrators for the burner and compare each scheme. Secondly, simulate and analyze the burning process of coal particle in this burner, and give an optimum structure for original burner. Start-up and 30%MCR of boiler are also studied using numerical method. Finally, adopt improved NOx global model using User Defined Function(UDF) which is an advanced function of Fluent software, to forecast the NOx formation process in 30%MCR of boiler. The study results will provide guidance for design and operation optimization of the burner and start-up and low load of boilers.