入口面积可变式旋风分离器的性能

当旋风分离器的进气流量(Q_in)小于设计流量时，分离效率会大幅降低。对此，笔者提出通过改变入口面积来保持或提高分离效率的解决方案。首先，以PV型旋风分离器为对象，通过冷态实验，对比了2种入口面积改变方式与分离效率的关系。结果表明,随着进气流量减小，入口面积减小可有效提高分离效率，且侧堵入口(BS型)的效果优于横堵入口(BT型)。流场模拟结果表明,与BT型旋风分离器相比，BS型旋风分离器的切向速度更大，径向速度峰值更小且更均匀，因此其分离效率更高。其次，设计了1种入口面积可变式(VIA型)旋风分离器，确定了入口面积调节方法，并测试了其分离性能。结果表明,当进气流量从最佳进气流量递减时，因其入口面积可随之变小，入口气速基本不变，而分离效率不降反升，并在实验范围(Q_in为2300~9700 m³/h)内一直保持较高的水平。

Performance of the Cyclone Separator With Variable Inlet Area

When the inlet flowrate (Q_in) of thecyclone separator is less than its design one, its efficiency will be greatlyreduced. In order to solve this problem, experiments and numerical simulationswere conducted on the influence of inlet area of PV type cyclone on theseparation efficiency. The experimental results show that the efficiency ofcyclones increases when the inlet area decreases. Moreover, it is found thatthe efficiency of the cyclone with a sidely-blocked inlet (BS type) is betterthan that of the cyclone with a transversely-blocked inlet (BT type). Thesimulation results show that the tangential velocity of BS type cyclone isgreater than that of BT type cyclone, and the radial velocity of BS typecyclone is smaller, which promotes the separation efficiency. For the VIA type,when the working flowrate decreases from its optimal flowrate, the inletvelocity remains the same or higher by reducing its inlet area, which couldensure a higher efficiency within the experimental range (Q_in is2300-9700 m³/h).