Experimental Study on Nonlinear Vibration of Cantilever Cylindrical Shell

Nonlinear dynamic behavior of a cantilever cylindrical shell is studied experimentally using non-contact type of electromagnetic shaker, acceleration measurements, and imaging of vibrating shell using two high speed 3D cameras. The response history and frequency spectrum are measured at different locations along the circumference of the free end of the shell for different excitation amplitudes and mode of vibration. The frequency response obtained from acceleration measurements is found to be in good agreement with the simulated response in ANSYS. The response histories from acceleration data and digital image correlation are compared for one case and found to match very well. The traveling wave phenomenon along with participation of higher harmonics and softening nonlinearity are observed. The traveling wave response is observed for certain range of forcing frequency for the shell excited in modes with number of circumferential waves n = 3 and 5. It is shown that the traveling wave response can be detected based on the phase angle difference of response at different circumferential locations.