A Contrastive Study Of Vibration Response Analysis Method For Thin-walled Cylindrical Shell

Thin-walled cylindrical shell structures have been widely used in many engineering areas for its high stiffness and small mass. Meanwhile the vibration response problems for thin-walled shell structure under dynamic loads have evoked great attentions for the scholars. Among various kinds of load forms, harmonic excitation is the most fundamental load form. Any complicated load form can be divided into a series of harmonic loads excitations. By using the linear superposition theorem of system, we can get overall response from every harmonic response; therefore, harmonic vibration response methods for the thin-walled shell structure have important scientific significance and great engineering value.In this dissertation, brief reviews about shell theories and the analysis methods for dynamic response of circular cylindrical shells are given. Then taking cantilever thin-walled cylindrical shell as a research object, analysis methods about the forced responses of shell under harmonic excitation are discussed. The main research contents in this paper are as following:(1) Based on thin-walled shell assumptions and Love shell theory, stationary thin-walled cylindrical shell vibration differential equations are established. Vibration response characteristics of thin cantilever cylindrical shell under radial harmonic excitation are discussed by using the principle of mode superposition.(2) Based on the thin-walled characteristic, the finite element model for cantilever cylindrical shell is established, By means of comparing the modal parameters (natural frequency and vibration modal shape) between modal experiment and FEM, the finite element model is verified.(3) In order to get the vibration response characteristics of cantilever nodal points of the FE model,which is under single-point excitation loads, harmonic response analysis and transient response analysis are performed for different vibrational state(resonant and non-resonant).(4) Key technologies are discussed including arrangement of testing points, shock excitation method and vibration response acquisition plan.A testing system are established to get the result of radial responses(of the measure point)for different vibrational state. Then the result is discussed.(5) Based on the FEM, resonant behavior of thin-walled cylindrical shell is analyzed. Through comparing results of vibration response, it is found that resonant behavior is related to the modal shape, and an experiment is taken to validate it.