双级旋风分离器特性的计算机预报

利用计算流体力学ＣＦＸ４．２ 软件对双级旋风分离器的气固两相流进行了三维数值模拟，采用贴体坐标系统描述复杂的几何边界和基于交错网格的网格系统；对于气相流场，采用雷诺应力模型计算旋转流动，在拉格朗日坐标中计算粒子运动．为优化求解，采用多块结构适体网格，利用ＳＩＭＰＬＥ 算法解离散方程；此外，给出了双级旋风分离器内不同截面的速度分布和５ 种不同尺寸共６０ 个粒子轨迹．研究结果表明，双级旋风分离器比常规的旋风分离器分离效果要好．

PREDICTION OF THE PERFORMANCE OF TWO STAGE CYCLONES

The gas solid two phase 3D swirling flow in a large scale cyclone modified with a two stages separation has been investigated by mathematical simulation with CFX4.2 codes. The gaseous flow was simulated by using Reynolds stress turbulence model,while the solid movement by Lagrangian approach. The computing method used is the SIMPLE method. The multi block grid methodology involving the use of an unstructured set of block is used. The moving trajectory of 60 particles of 5 kinds of different sizes with a certain solid fraction and various sections velocity field were traced by the computer calculation. It has been confirmed that the two stage separation in the inner tube will improve the efficiency of the cyclone.