旋风分离器入口结构改进及其对“短路流量”的影响

常规切向进口旋风分离器的气流进入旋风分离器后必定要经过排气芯管外壁和筒体内壁之间,因此不可避免会使得相当一部分气流没有经过分离空间而直接从排气芯管底部排出(短路流量),这也是影响旋风分离器分离效率的重要因素之一。在前人工作的基础上,对旋风分离器的进口结构进行了改进:使得旋风分离器的入口具有一定截面角,并借助数值计算技术,分别对传统的和具有一定入口截面角旋风分离器内的三维流场进行了数值模拟,计算了芯管底部的"短路流量",结果表明:进口具有一定截面角可以明显减小芯管底部的"短路流量",这对改善旋风分离器的分离效率具有重要的实际意义。

Effect of the Improvement of Inlet Geometry of Cyclone Separators on Shortcut Flow Rate

When the gas flow goes into a conventional cyclone separator with a tangential direction inlet, some gas must traverse the region between the outer wall of the vortex and the inner wall of the cylinder, therefore, part of gas flow discharges directly from the vortex finder without arriving at the separation space (named shortcut flow). The shortcut flow is one of important parameters affecting the separation performance of a cyclone separator. In this study, certain improvement was made for the inlet geometry based on previous works, i.e., a section angle was designed in the inlet region of a cyclone separator. Moreover, three dimensional flow fields of the conventional cyclone separators and those with certain section angles at the inlet region were simulated and the shortcut flow at the bottom of the vortex finder was calculated. The result indicated that the inlet section angle of cyclone separators could reduce markedly the shortcut flow rate from the bottom of the vortex finder, which is practically important to improve the separation efficiency of cyclone separators.