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本文以一种电子元件冷却用的单级微型轴流风扇为研究对象,数值模拟研究其内部的非定常流场,分析了动静干涉下叶表压力的非定常响应特征及其产生机理.研究发现,下游静叶前缘附近的高压力梯度是引起上游转子叶表压力波动的主要原因.该势干扰在向上游转子通道内的传播过程中,转子吸力面附近存在一个扩张区域,该区域内的压力波动相位相同.但在扩张区之外扰动具有轴向指向性,导致压力面上的波动存在相位差.对于下游静子而言,转子尾迹改变了来流冲角,但是这种影响仅限于叶片前缘的滞止点附近的区域;在静叶后半段压力波动微弱.“,”In this paper,the unsteady flows in a micro-axial fan stage which is widely used in cooling systems of electronic devices are numerically investigated.The study is focused on the characteristics and the mechanism of unsteady responses of the pressure on blades caused by rotor-stator interactions.The pressure fluctuation on the blade surface of the upstream rotor is mainly caused by the high pressure gradient around the leading edge of the stator blades.During the propagation process of the potential interaction,there exists an expansion region in which the pressure fluctuation is in phase with that on the suction surface.While in outside of the expansion region,clear axial directivity of the propagation is observed.Hence,the pressure changes in phase on the suction surface,while phase lag is observed on the pressure surface.For the downstream stator,the rotor-wake changes the attack angle of the stator,because of the velocity deficit.However,the effect of this change is only in around of the stagnation point.The unsteady response in the second half of the stator surface is weak.