四通道燃烧器冷态流场优化的PIV测量

利用粒子成像测速仪PIV对水泥生产中回转窑冷态模型内四通道燃烧器出口附近的流场进行测量，考察不同的轴流风、旋流风、煤风和中心风之间的比例关系对流场的影响作用，分析了四种不同工况下的燃烧器出口的流场特性．结果表明轴流风和旋流风速度对燃烧器形成的射流场影响最显著．其中轴流风促进内部回流区的形成，旋流风减弱内回流区的形成，但能够加强流体和煤粉的充分混合，避免煤粉燃烧时局部高温区的形成．因此适当增加轴流风量和旋流风量可以起到降低烟气中的NOx含量的作用．

Measurement of the flow field of four-passage combustor with PIV

The flow field near the outlet of a four-passages combustor inside a rotary kiln was measured with particle image velocimetry(PIV).The effect of the ratio relationship,especially axial air,swirl air,coal air and centre air,on the flow field was analyzed,and the combustor outlet flow field properties of different conditions were discussed.The result shows the velocity of axial air and swirl air makes a prominent influence on the jet flow of field of combustor,and axial air promotes the formation of the inner region of back flow.Swirl air reduces the formation of the inner region of back flow,but reinforces the mixture of coal and fluid,avoiding the formation of local high-temperature region.Therefore,the proper increase of the axial air and swirl air quantity can reduces the emission of NO_x.