升气管插入深度对旋风分离器内部流场影响的数值模拟

Numerical Simulation of the Influence of the Lengths of Exit Tubes on the Internal Flow Field of Cyclone Separators

针对旋风分离器内部复杂的三维强湍流,在仿真过程中,采用雷诺应力模型(RSM),利用贴体网格技术,模拟得到不同升气管插入深度时的旋风分离器内的切向速度分布、轴向速度分布和进出口压降。结果表明,当升气管插入深度减小时,会使总压力损失有所降低,但有一部分气流将从入口直接进入升气管形成短路,使旋风分离器的分离性能下降;对于特定的旋风分离器,升气管插入深度存在最优值,可保证较高的分离效率和较低的压降。

In a simulation process, the tangential velocity distribution, axial velocity distribution , and imported and exported pressure drops of the different lengths of exit tubes in cyclone separators were derived through simulation using Reynolds Stress Model（RSM） and Body-Fitted Coordinates Grids （BFC） for the complex three-dimensional strong turbulent flow in cyclone separators. The result shows that when the reduction of the length of exit tubes can make the total pressure loss decrease, but some of the air flow would directly enter the exit tubes through the inlets to form a short circuit to lower the performance of the cyclone separators. There is an optimum value for the lengths of exit tubes for given cyclone separators that can guarantee comparatively high separation efficiency and low pressure drop.