离心风机内部流场数值优化研究

Aerodynamic optimization design with numerical simulation for centrifugal fan

以一小型离心风机为研究对象,首先根据国标设计一套进口风管风机测试装置对其进行测试,然后利用流体分析软件ANSYS CFX对其进行三维数值模拟,将试验测试结果和数值计算结果进行对比,得到模拟计算结果与试验测试结果基本一致,验证数值结果的准确性。接着对风机内部加装一防涡圈进行模拟计算,结果表明加装防涡圏后,蜗壳内部尤其叶轮和蜗壳前板之间的漩涡明显减小,漩涡强度减弱,流场得到改善,泄漏损失明显减小。另外对不同泄露间隙的风机进行数值计算,结果显示随着间隙的减小,泄漏量明显减小,所以在保证安全运行的条件下,间隙应尽可能小。

A small centrifugal fan was taken as the object of study. First,a duct test device was designed and test this fan. A three-dimensional numerical simulation on centrifugal fan was conducted with ANSYS CFX. The test results were compared with the numerical results and the simulation results were basically consistent with the test results. To break vortexes and reduce the internal leakage losses,a type of arc anti-vortex rings was installed to the fan. Another numerical investigation was also conducted for the fan with the rings. It was found that the flow field performance was improved and the cubage loss was reduced. The fan with the different clearance between inlet and blade was also simulated. The results showed that the leakage was significantly reduced with the decrease of the gap. Ensuring the safe operation conditions,the gap should be as small as possible.