Structural Frequency Response Function Prediction and Experimental Validation between Aircraft Engine Mount and Pylon
Abstract— Structure frequency response function (FRF) prediction and validation are necessary for aircraft noise and vibration engineering. With the frequency response functions (FRFs), the vibration transmission characteristic can be evaluated by engineer so that potential structure resonance behavior can be found at specific frequencies. In this paper, the concerned vibration frequencies come from the engine low pressure rotor and high pressure rotor during engine operation in cruise condition. The finite elements model of engine mount, pylon and pylon spar with fuselage was established and the frequency response functions between the engine mount excitation location and the pylon response locations were calculated. Then hammer method was used to acquire actual frequency response functions to validate the calculation results. The comparison results show that it was in good agreement between the calculated results and experimental results. From these frequency response functions, it could be evaluated that there was no resonant characteristics for the engine mount, pylon and pylon spar with fuselage structures at the concerned frequencies and there was no risk for the structure-borne noise problem caused by engines.
Index Terms— FRF calculation, FRF testing, structural mode, hammer method, engine vibration.
Junwei Xu, Luyao Ge, Feng Han, Huayong Zhao
Functional Structure Department, Shanghai Aircraft Design and Research Institute, CHINA
Cite: Junwei Xu, Luyao Ge, Feng Han, Huayong Zhao, "Structural Frequency Response Function Prediction and Experimental Validation between Aircraft Engine Mount and Pylon," Proceedings of 2019 the 9th International Workshop on Computer Science and Engineering, pp. 387-394, Hong Kong, 15-17 June, 2019.