基于波形分解法研究叶片表面压力波动

Investigation of Unsteady Profile Pressure Based on the Decomposition of Characteristic Waveform

本文以某一组合压气机为研究对象,采用数值方法模拟三排叶片在设计工作点的非定常流场。依据转/静/转模型中静叶表面压力波动幅频特性,确定影响静叶表面压力波动的因素,通过对比转/静/转模型和时序模型中静叶表面压力分布情况,获得上下游动叶叶片数目对中间叶片表面压力分布影响。最后引入转/静模型,通过应用模型分解减法获得两组影响因素相对叠加相位,从而揭示上下游叶片数目和时序位置影响中间叶片表面压力分布机理。结果表明:上下游动叶叶片数目的异同直接影响中间静叶表面压力波动的周期特性。两组影响因素的相对叠加相位决定着压力波动幅值大小。

Numerical simulations of the three-dimensional unsteady viscous flow field of three cases, R/S/R case with unequal rotor blade numbers, R/S case and clocking case, were performed at design point. The data from R/S/R were analyzed to find out the influence, which drives the static pressure fluctuated with time on the stator blade surface; the data from the clocking case were investigated to understand the period of unsteady pressure fluctuation and conclude the relationship between the static pressure fluctuation and clocking positions; the R/S case was employed to obtain the influence from upstream rotor. The results show that the amount of the rotors＇ blade decided the period of the static pressure fluctuation. Besides, clocking positions play an important role in the amplitude of the static pressure fluctuation for clocking case.