螺杆空压机用多翼离心风机气动性能改进

Improvement on Aerodynamic Characteristics of Multi blade Centrifugal Fan of Screw Air Compressor

为研究多翼离心风机原型机出口风速均匀性差机理,采用CFD数值模拟技术,计算风机内部气动性能及出口风速分布规律,并通过实验验证了计算模型和计算方法的准确性。计算结果显示该风机存在内部流场紊乱、叶道内涡旋多且蜗舌处回流严重等问题,最终造成风机出口均匀性差。在保证安装接口一致的前提下,通过优化风机进口集流器、叶片结构、叶片数量、蜗壳型线及扩压器等参数,改善了进气流道以及风扇与蜗壳匹配性,有效提升风机内部气动性能,消除涡流和回流现象。同时在扩压器进气口处增加整流破涡设计,进一步改善风机出口均匀性。实验结果表明:风机出口风速差值由10m/s降低至3m/s。

In order to study the mechanism of poor uniformity wind speed at outlet of primary multi-blade centrifugal fan,CFD technology was used to calculate the internal aerodynamic performance and outlet wind speed distribution of the fan.The accuracy of the calculation model and method was verified by experiments.The results show that internal flow field of fan is disordered,vortices at blade channel and serious backflow near volute tongue leads to poor outlet uniformity.On the premise of the same installation interface,inlet passage and the matching between fan and volute are improved by optimizing the parameters of fan inlet collector,blade structure,blade number,volute profile and diffuser,so as to effectively improve the internal aerodynamic performance of the fan.Besides that,the uniformity of fan outlet is improved by a rectifier added at the inlet of diffuser.Experimental results show that difference of wind speed at fan outlet decreases from 10m/s to 3m/s.