周向畸变对跨声速风扇低阶强迫振动的影响研究  

Effects of Circumferential Distortion on Low-Order Forced Vibration of Transonic Fan

作　　者：穆泽 潘天宇 闫昭琦 郑孟宗 MU Ze;PAN Tian-Yu;YAN Zhao-Qi;ZHENG Meng-Zong(School of Energy and Power Engineering,Beihang University,Beijing 100191,China;Research Institute of Aero-Engine,Beihang University,Beijing 100191,China)

机构地区：[1]北京航空航天大学能源与动力工程学院,北京100191 [2]北京航空航天大学航空发动机研究院,北京100191

出　　处：《工程热物理学报》2022年第2期324-330,共7页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.51706008,No.51636001,No.51976005);国家科技重大专项(No.2017-II-0005-0018)。

摘　　要：边界层抽吸式推进系统(BLI)因具有降低未来商用飞机燃油消耗率的巨大潜力而备受关注。但风扇叶片作为关键组件,需要受到由于边界层吸入而导致的畸变来流的挑战。基于本团队前期在NASA Rotor 67进行的数值模拟,在设计转速附近风扇因受到二阶激励而以一阶弯曲的形式发生低阶模态振动,同时,激发的强度足以引起叶片振动。由于来流周向畸变变化范围随BLI推进系统而变化,因此其对低阶振动的影响值得研究。本文考虑了五个不同畸变来流角度,进行了NASA Rotor 67的三维非定常仿真和模态力分析。结果表明,低阶振动形式在不同的畸变角度下保持不变,但随着变形程度的增加,模态力的大小先增大然后减小。存在两个引起叶片振动的激励源,它们包含在畸变来流中,并在叶片通道中的引发。Boundary layer ingestion propulsion systems have attracted much attention due to significant potential to reduce the fuel consumption of future commercial aircraft.However,the fan blade,as a key component,needs to be designed to overcome the challenge of distorted inflow due to boundary layer ingestion.Based on the numerical simulation of NASA Rotor 67 under a BLI-type inlet distortion,previous study revealed that the resonance between second-order excitation and first-order bending mode is detected near the design rotor speed.At the same time,the magnitude of excitation is strong enough to induce blade vibrations.Due to that the circumferential extent of inlet distortion varies with the BLI propulsion systems,the effect of it on low-order vibration is significant to be investigated.Thus,five inlet distortions with different distorted extents are considered in this study.By the 3D unsteady simulation and modal force analysis of NASA Rotor 67,the results demonstrate that the low-order vibration modes remain unchanged under different distorted extents.However,with the increase of distortion extent,the magnitude of modal force starts to increase and then decreases.To cause the blade vibration,there are two significant sources of second-order excitation,which are included in distorted inflow and induced by the transient state in the blade passage.

关 键 词：低阶模态振动 畸变角度 模态力 

分 类 号：V215.3[航空宇航科学与技术—航空宇航推进理论与工程]