分布式送风空调用多翼离心风机集流器的优化研究

Optimization Study of Bell Mouth on Multi-blade Centrifugal Fan Used in Distributed Air Supply Conditioner

通过对分布式送风空调用多翼离心风机进行CFD分析,对比了几种不同结构型式的集流器,并结合实际测试寻求对多翼离心风机的性能及噪声最佳优化方案的集流器型式。研究结果表明,不同集流器结构型式对多翼离心风机风量、噪声有较大影响。改变集流器的圆弧面导流结构,根据气流进入集流器后流动特性增加的集流器内侧扩口,能提升多翼离心风机风量2.3%;增大集流器内径,当集流器包围住叶片宽度的一半左右时风机风量最佳,即(叶轮外径-集流器内径)≈(叶轮外径-叶轮内径)/2时,多翼离心风机风量最佳;集流器增加内侧挡筋后,叶轮前端面与蜗壳间间隙泄漏量减少,风量提升10.7%,噪声降低1.2 dB。

The CFD software was used to analyze multi-blade centrifugal fans for distributed air supply conditioners,compared with several different types of bell mouth,and combined with actual tests to find the best optimized type of the bell mouth for the performance and noise of multi-blade centrifugal fans.The research results show that different structure forms of bell mouth has a great influence on air volume and noise of multi-blade centrifugal fan.By changing the circular arc surface of bell mouth diversion structure,the increased flaring inside the bell mouth according to the air flow characteristics after entering bell mouth can increase the air volume of the multi-blade centrifugal fan by 2.3%;By increasing the bell mouth diameter,when the bell mouth encircles about half of the blade width,the fan air volume is best,namely,(the impeller diameter-bell mouth diameter)≈(impeller outer diameter-impeller inner diameter)/2,the multi-blade centrifugal fan has the best air volume;After adding the inside block ribs in the bell mouth,the air leakage through the gap between the front face of the impeller and volute was reduced,air volume was increased by 10.7%,and the noise was reduced by 1.2 dB.