防涡圈对离心风机性能影响的探讨

摘要

针对某离心通风机模型，研究了防涡圈对风机性能的影响。数值模拟和试验结果都说明了加装防涡圈后全压升和效率有所下降，这与以往的认知不完全一致。设计工况下，未加装防涡圈的通风机全压升比加装长防涡圈的风机高出约4％，效率高出约3％，内泄漏情况也会随防涡圈长度的增加变得严重；从内部流场可以看出，加装防涡圈减小了蜗壳内部的扩压空间，叶轮出口大尺度漩涡更加剧烈，影响了叶轮出口气流方向，并在叶轮出口产生回流现象，降低了通风机的全压和效率。因此认为对于不同压力系数和流量系数的风机，防涡圈对风机性能的影响规律是不一样的。%Affection of anti-vortex ring on the performance of a centrifugal fan model has been studied.The results of numerical simulation and experiment explains that total pressure and efficiency decrease after the anti-vortex ring installed,which is not en-tirely consistent with previous knowledge.According to the results of numerical simulation and experiment,the total pressure and efficiency of centrifugal fan with no anti-vortex ring are about 4% and 3% higher than the centrifugal fan with long anti-vortex ring,internal leakage also becomes worsen with the increasing length of anti-vortex ring.According to the internal flow field analy-zing,the space in volute becomes small because the installation of anti-vortex ring,large vortex at the impeller outlet becomes more intense,which affects air flow direction at the impeller outlet,backflow phenomenon take place at the impeller outlet,total pressure and efficiency of the centrifugal fan model will decrease.As a result,it can be concern that the anti-vortex ring causes different impaction on centrifugal fan of different pressure coefficient and flow coefficient.