对旋式通风机全流道与单流道内部流场的对比分析

Comparative analysis on flow field inside whole flow channel and single flow channel of contra-rotating fan

分别建立对旋式通风机全流道模型和单流道模型,应用标准κ-ε湍流模型和SIMPLE算法,求解三维时均雷诺N-S方程,对对旋式通风机全流道和单流道进行三维定常湍流流场的数值模拟,得到前后级叶片压力面与吸力面、3个轴向位置截面的压力分布图。将二者结果对比分析发现:由于两级叶片的交互作用,从全流道的计算结果可以看出,叶轮流道截面图上的压力并未显示出良好的周向对称性,并且单流道模型的设定只是一种近似,所以若要获得更为全面准确的流场信息,应选用全流道模型进行数值模拟。这也为对旋式通风机计算模型的选取提供参考。

The model of the contra-rotating fan with whole flow channel and the one with single flow channel were separately established, standard κ- ε turbulent model and SIMPLE algorithm were applied to solve 3D Reynoldsaveraged Navier-stokes equations. In addition, numerical simulation on 3D steady turbulent flow field inside the whole flow channel and the single flow channel was carried out, and the stress distributions on pressure side and suction side of anterior and posterior stage of blades as well as those on section of three axial locations were obtained. Comparative analysis of the two results showed: due to interaction of two stages of blades, the calculation results of the whole flow channel indicated poor circumferential symmetry of the stress on section of the impellor flow channel; because of the model of the single flow channel being approximately established, to achieve comprehensive and accurate data about flow field, the model of the whole flow channel should be selected to carry out numerical simulation. The analysis results offered reference for selecting calculation model of the contra-rotating fan.