静子开缝高度对高负荷两级风扇性能的影响

Effects of Height of Stator Slot on Performance of High-Load Two-Stages Fan

为了研究静子开缝高度对高负荷风扇性能的影响,根据风扇的流动特点,设计了在第二级静子叶根处开缝的流动控制方案,并提出了多种不同缝隙高度的静子开缝方案,通过计算对采取各种方案下的流场进行了分析。研究表明,缝隙射流可阻断静子吸力面气流的径向流动,吹除缝隙出口后的低速气流,从而达到扩稳的目的,设计转速下方案A的风扇稳定工作范围扩大了7.1%;在不同工况下静子开缝对角区气流分离和流动损失均有一定的控制效果,而在堵塞工况下,由于静子通道内流动分离较小,开缝射流的优点没有得到充分体现;在所研究的范围内,当开缝高度较低时,缝隙射流对角区分离和流动损失的控制能力较弱,而开缝高度的增加对控制叶根角区气流分离有利,对控制较大叶高处吸力面的气流分离不利。

In order to study impacts of the height of stator slot on performance of high-load fan, the slotted blade flow control programs before the root of the second stator were designed based on the feature of fan flow. Dif- ferent height of blade slot programs were presented and the changes of fan aerodynamic performance and flow structure resulted from different programs were simulated. The results show that the slotted blade could control the radial flow on suction surface, decrease low momentum flow after the outlet of slot and finally increase the flow stability, and config A has 7.1% stable working range increase at design speed. The control program could cause corner separation suppressed and lower pressure loss in all conditions expect the blockage condition which has less separation in the stator passage. Within limits of our study, it will cause unsatisfactory control on corner separation and flow loss if the height is lower, while it will have optimistic effects on corner flow control but un- fulfilled control on the high part of blade suction surface flow if the height is higher.