风扇级负荷对其进口总压畸变响应特性影响研究

基于不同转子级负荷下的风扇压气机叶排实验特性,应用畸变传递的矩阵分析模型,对不同级负荷下的风扇压气机转子叶排、静子叶排的容进口总压畸变特性进行了详细分析,初步建立了级负荷对总压畸变及其沿轴流压气机叶排衰减特性影响规律。计算结果表明,提高转子级负荷在设计工况附近能有效提高转子叶排容总压畸变能力,但在接近失速工况下其容总压畸变能力明显降低;不同转子负荷下其后静子叶排容畸变特性存在明显差异,这对合理选择风扇压气机设计级负荷尤为重要。

Exploring Attenuation of Steady Circumferential Pressure Distortion of Axial Flow Compressor with Axial Fan Stage

Recent developments in high loading multistage axial compressor~() makes the attenuation of its steady inlet circumferential distortion increasingly imperative.Our aim is to explore the effect of fan rotor load on the response of an axial flow compressor to steady inlet circumferential total pressure distortion in order to make the fan stage load as conducive as possible to faster attenuation of its steady inlet circumferential distortion.A simulation technique of matrix transfer model is developed for the prediction of the decay of inlet circumferential total pressure distortions through any combination of rotors,stators and clearances.The method and model are applied to two transonic axial fan stages.Detailed numerical results are given in figures and tables of the full paper;in this abstract we just discuss the trends revealed by numerical results.Numerical results show that:(1)great attenuation of total pressure distortion through the rotors and weak attenuation of that through the stators downstream of the rotors are obtained with high rotor loading near fan design conditions;(2) for surge conditions,low decay rate through rotors and even amplification through stators downstream of the rotors are found with both high and low fan loading cases;(3)compared with the results of low fan loading rotors,higher attack angles at rotor inlet and narrower surge margins are observed with high fan loading rotors;(4) although phase profiles at fan stage exit of total pressure distortion and static pressure distortion are opposite near design conditions,these profiles disappear near surge conditions.So,it is shown that flow coupling condition under steady inlet circumferential total pressure distortion given by Greitzer is,in our opinion,only applicable to certain working range of the axial fan stage.Appropriate design of the fan rotor load for multistage fan compressors must be considered to make the axial fan compressors have high tolerance to inlet pressure distortions.