Experimental investigation on dynamic response of flat blades with underplatform dampers  

作　　者：Dayi ZHANG Bin GAO Jie HONG Jianwei FU Xiangyun GE 

机构地区：[1]School of Energy and Power Engineering,Beihang University,Beijing 100083,China [2]Beijing Key Laboratory of Aero-Engine Structure and Strength,Beijing 100083,China [3]Collaborative Innovation Center of Advanced Aero-Engine,Beihang University,Beijing 100083,China

出　　处：《Chinese Journal of Aeronautics》2019年第12期2667-2678,共12页中国航空学报（英文版）

基　　金：the financial support from the National Natural Science Foundation of China (Nos. 11772022, 91860205 and 51475021);the experimental devices provided by Key Laboratory of Vibration and Control of Aero-Propulsion System, Ministry of Education, Northeastern University (VCAME201602)

摘　　要：One test rig with three blades and two Under-Platform Dampers(UPDs) is established to better understand the dynamical behavior of blades with UPDs. A pre-loaded spring is used to simulate the centrifugal load acting on the damper, thereby achieving continuous adjustment of the pressing load. UPDs with different forms, sizes and materials are carefully designed as experimental control groups. Noncontact measurement via a laser Doppler velocimeter is employed and contact excitation which is performed by an electromagnetic exciter is adopted to directly obtain the magnitude of the excitation load by a force sensor mounted on the excitation rod. Particular attention is paid to the influence of the contact status of the contact surfaces, e.g. the pressure-sensitive paper is used to measure the effective contact area of the UPDs. The experimental variables are selected as the centrifugal force, the amplitude of the excitation force, the damper mass, the effective contact area, and the damper material. The Frequency Response Function(FRF) of the blade under different experimental parameters is obtained by slow frequency sweep under sinusoidal excitation to study the influence of each parameter on the dynamic characteristics of the blade and the mechanism analysis is carried out combined with the experimental results.One test rig with three blades and two Under-Platform Dampers(UPDs) is established to better understand the dynamical behavior of blades with UPDs. A pre-loaded spring is used to simulate the centrifugal load acting on the damper, thereby achieving continuous adjustment of the pressing load. UPDs with different forms, sizes and materials are carefully designed as experimental control groups. Noncontact measurement via a laser Doppler velocimeter is employed and contact excitation which is performed by an electromagnetic exciter is adopted to directly obtain the magnitude of the excitation load by a force sensor mounted on the excitation rod. Particular attention is paid to the influence of the contact status of the contact surfaces, e.g. the pressure-sensitive paper is used to measure the effective contact area of the UPDs. The experimental variables are selected as the centrifugal force, the amplitude of the excitation force, the damper mass, the effective contact area, and the damper material. The Frequency Response Function(FRF) of the blade under different experimental parameters is obtained by slow frequency sweep under sinusoidal excitation to study the influence of each parameter on the dynamic characteristics of the blade and the mechanism analysis is carried out combined with the experimental results.

关 键 词：Effective contact area Forced response FRICTION Test rig Turbo machinery Underplatform dampers 

分 类 号：V232.4[航空宇航科学与技术—航空宇航推进理论与工程]