四墙切圆浓淡燃烧器射流特性的实验研究

Experiment Research on Jet Characteristics of Bias Burners for the Four-wall Tangential Firing

为了解四墙切圆燃烧中一次风的射流特性,本文采用实验室冷态模化实验,用PDA测量了分别采用水平浓淡燃烧和垂直浓淡燃烧方式的一次风射流流动特性。实验结果表明,由于燃烧器高宽比的差异,水平浓淡燃烧的气流刚性较强,也说明当燃烧器喷口数量比较多时,在采用这种四墙切圆燃烧时,喷口应该采用分组布置,这样可以降低每组燃烧器的高宽比,提高气流的刚性,从而有效减轻气流贴壁的状况。此外,研究表明采用水平浓淡燃烧的贴壁风速较高,是应该予以关注的。

For study the jet characteristics of the primary air with the four - wall tangential firing, a cold modeling experimental device was set up and the PDA was used to test jet characteristics of the primary air based on two unit boilers with wall tangential firing burners as the prototypes, which one is applied horizontal bias burner, another is applied vertical bias burner. Through the experiment with PDA test, the paper studies the airflow characteristics of the two kinds of bias burners. The study shows that, due to the difference of the height to width of the both burners, the jet rigidity of the horizontal bias burner is stronger. Also, for the four - wall tangential firing, if the amount of the nozzle of each burner is too many, grouping layout should be adopted to reduce the burner height -width ratio so that the airflow could be more rigid, and it biasing to the wall could be lightened effectively. The study also shows that, for the four- wall tangential firing, the speeds closed the wall are somewhat high, it should be concern.