不同数量并联微旋风分离器分离性能影响研究

Effects of numbers of parallel micro-cyclone separators on separation performance

为了考察不同并联旋风分离器的分离性能,运用计算流体力学(CFD)软件对由不同数量、直径为 30 mm 的微旋风元件构成的并联分离器性能特征进行了数值研究。结果表明,当微旋风元件入口气速一致时,增加微旋风元件数量,虽然各并联分离器对 5 μm 以下、中位粒径 3.5 μm 颗粒的总分离效率基本相同,但对 3 μm 以下颗粒的分级效率有所下降;组合分离器灰斗中排尘管间间距减小,微旋风元件内切向速度分布几乎不变,中心轴向速度下降,排尘管尾端气流更加紊乱;随着微旋风元件数量增加,各组合分离器微旋风元件排尘管段旋流稳定性系数 Sv 沿轴向逐渐增大,微旋风元件内旋流稳定性变差。

The performance of parallel separators composed of different numbers of micro-cyclone elements (diameter = 30 mm) was numerically studied by CFD. The results show that when the inlet gas velocity keeps constant and the numbers of micro-cyclone elements increases, the total separation efficiency of each combined separator decreases in treating particles with diameter less than 3μm, although this value has not obvious variation for particles with diameter <5 μm and volume average particle size = 3.5 μm. As the number of micro-cyclone element increases, the space between the dust discharge tubes in the dust bowl decreases and the tangential velocity distribution in the micro-cyclone element remains almost unchanged. The central axial velocity decreases and air low at the dust discharge tube tail becomes more disorder. As the number of micro-cyclone element increases, the cyclone stability coefficient (Sv) of the dust tube gradually increases along the axial direction, and the cyclone stability in the micro-cyclone element decreases.