Identification of harmonic load acting on an elastically supported thin plate linked with attachments

Abstract

Plate-like structures in real mechanical system is always simplified and modeled as an elastically restrained thin plate loaded with stiffness or mass. The dynamic model of the plate distinguished with previous classic model is complex vibrational characteristics and merely proposed by numerical method. Accordingly, identification of harmonic load acting on this plate becomes difficult for hardly obtaining inverse equations or matrix from its response functions directly. To solve this problem, dynamic model of the plate is established by numeric method and combined with particle swarm optimization (PSO) method to reconstruct harmonic load by minimizing total error between vibration responses in identification and test. Then, it is used to deal with acceleration responses tested in an elastically supported plate derived by a harmonic load. Parameters of the harmonic load are identified and found to agree with those of real source by their comparison. Thus, it is concluded that harmonic load driving on the plate linked with elastic boundary and attachment can be identified accurately by proposed numeric model of this paper. Furthermore, acceleration distribution of the plate at modal frequencies and responses at different test point, which are acquired from identification and test, are demonstrated and discussed. It is revealed that the numeric model proposed in this paper identifies parameters of harmonic load mainly through tendency of vibration distribution on the plate, and the accuracies of its reconstruction results at some locations are limited.