新型等离子体点火燃烧筒研究

Study on new type of plasma ignition combustor

以装有150kW等离子体发生器的某等离子体点火试验燃烧器为例,应用数值模拟的方法对等离子体点火燃烧器的稳燃性能进行了研究,并提出了一种新型的径向/切向进风等离子体点火燃烧筒.研究结果表明,一次风速(风粉气流流速)、等离子体气流的穿透区域和煤粉浓度等是影响等离子体点火过程及煤粉着火燃烧的主要因素.径向/切向进风可以在燃烧筒内形成多向回流和旋流,使得风粉气流在燃烧筒内不仅有轴向速度,而且还有径向和切向速度,改变了轴向进风气流运动的单一性,增加了煤粉气流在筒内的停留时间,着火区域扩大,火焰充满度好,有利于燃烧筒内的稳燃.

Ignition and stabilization of coal combustion in some experimental plasma ignition burner with 150 kW plasma torch is analyzed.The main factors affecting the plasma ignition process and pulverized-coal combustion in plasma combustor are investigated.Based on the stabilization and combustion problem analysis,a new type plasma combustor with radial/tangential primary flow inlet is put forward and the characteristics of this type of combustor are also investigated.The research result shows that the primary velocity（pulverized-coal flow velocity）,plasma flame area,plasma flow temperature and pulverized-coal particle density are the main factors for the plasma ignition process and pulverized-coal ignition.The plasma combustor with primary radial/tangential inlet can produce recirculation zones and swirl flow in the combustor.In addition,the velocity field and temperature field between two type inlet designs are compared.