本文分别对采用常规单圆弧叶片和等减速叶片两种不同型线叶轮的离心风机进行了试验研究,并做了整机全工况数值模拟计算。流场分析表睨:应用等减速流型设计的离心风机,其叶轮内部的流动损失小,压力梯度变化更规律,叶轮出口的射流-尾迹结构较弱,出口速度场均匀且最大速度值较低。所以,等减速流型设计的叶轮,其流动损失、扩压损失、出口混合损失以及出口截面突变损失均比较小,效率较高。
Performance experiments and numerical simulations were conducted on two centrifugal fans with different impellers but the same nozzles and casings. In one impeller the blades were circular arc-shaped, while in the other one the blades were designed by using uniformly decelerated flow model. By investigating the flow fields closely, it was revealed that, inside the impeller with the blades designed by uniformly decelerated flow, the flow losses was less, the variation of the pressure gradient was more regular and the jet-wake flow at the impeller's exit sections were weaker. Therefore the conclusion can be drawn that, in the uniformly decelerated flow impeller, the flow losses, the diffusion losses, and the losses caused by abruptly enlarged cross section from the impeller to casing are all little, and all these factors contribute to the fan's high efficiency.