Identification of structural modal parameters based on sound pressure measurement
XIA Maolong1, LI Sheng1,2
1.State Key Laboratory of Structural Analysis for Industrial Equipment, School of Naval Architecture,Dalian University of Technology, Dalian,116024
2. Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, China
Based on the frequency response function of sound pressure, the method of identifying structural modal parameters by measured sound pressure is proposed. It can accurately identify the structural natural frequencies, damping ratios and mode shapes with the measured sound pressure, and can avoid mass loading due to use of vibration sensors on the structure. Combined with the structural dynamic equations, the sound pressure frequency response function is established based on the boundary element method and the Rayleigh integral formulation for sound radiation from an arbitrary body. The method is also able to identify the structural modal parameters with Single-Input-Multiple-Output testing and Multiple-Input -Single-Output testing. Finally the accuracy and the validity of the method are verified on the basis of the numerical simulation experiments.
夏茂龙1，黎胜1,2. 基于声压测量的结构模态参数辨识[J]. 振动与冲击, 2017, 36(22): 232-238.
XIA Maolong1, LI Sheng1,2 . Identification of structural modal parameters based on sound pressure measurement. JOURNAL OF VIBRATION AND SHOCK, 2017, 36(22): 232-238.
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