HM型等离子燃烧器多级燃烧特性数值模拟

用Fluent软件对HM型等离子燃烧器的点火燃烧特性进行了二维数值模拟，计算了煤粉空气混合物从等离子点火区到炉膛内主要断面的温度场、着火过程成分变化和煤粉进入炉膛初期的燃尽率等。结果表明：一级燃烧筒内的煤粉在离开等离子体点火区距离约D1（一级筒直径）的部位挥发分开始着火；一级燃烧筒中心线上的温度从点火区开始首先降低然后升高；二级煤粉在距离二级燃烧筒入口约2倍D2（二级燃烧筒直径）处开始着火，二级燃烧筒断面温度中部高四周低；三级煤粉在距离二级燃烧筒出口约2m处开始着火，并形成稳定的火球状火焰。计算结果还表明：燃烧器燃尽率较高，当形成稳定的火焰时，挥发分已经完全燃烧，碳的燃尽率达到46%以上。

Using CFD to Simulate Lignite Plasma Ignition Burner Stage by Stage Combustion Feature

A simulation investigation into the combustion feature in a lignite plasma burner is presented. The numerical simulation focuses on some ignition factors such as the combustion section temperature, combustible component and the burner combustion efficiency. The result shows that the first stage pulverized coal powders are ignited quickly in the distance about one diameter of the first chamber, and the volatile is ignited first; after passing through the plasma area, the center temperature of the chamber decreases first from the ignition area and then increases. The second stage pulverized coal powders are ignited in the distance about two diameters of the 2nd chamber. The left pulverized coal powders go into the furnace along with the two stages flame; being heated by the flame, the temperature of the third stage pulverized coal powders increase and the third stage powders are ignited in the furnace about 2 meters afar from the out of the burner, with a ball shape flame where the coal combustion efficiency is more than 46%.