旋流式分离器三维流场测定

INVESTIGATION OF 3D FLOW FIELD IN VORTEX TYPE CYCLONE SEPARATOR

在Φ196mm的实验模型上,用五孔球形探针较详尽地测量一、二次气不同流量比例和不同结构情况下旋流式分离器的三维速度场及压力场。得到了切向速度在分离器中部为准强制涡,外部非喷嘴区为准自由涡和喷嘴区为随半径先降后升的分布形式,在一定的一次气旋流器结构和参数条件下,轴向速度存在滞流和倒流现象,从流场上解释了形成准滞止灰环的原因,此外,初步分析探讨了形成螺旋形灰带等问题。

3-Dimensional flow field and pressure distribution in vortex type cyclone separator are investigated in detail on a φ196 mm test model with 5-hole ballprobe under different first and secondary flow rate ratio and different shape of structure parts. The results show that the tangetial velocity profile follows quasi forced vortex distribution in the outer part of the separator but near the nozzle area it first decreases and then increases with the radius. Under original guide vane shape and certain flow rate regime, secondary vortex and reverse flow exist which explains the cause of appearing quasi stagnating dust ring. Mechanism of producing spiral shaped dust ring for achieving good performance is also analysed preliminarily.