Identification of cubic nonlinearity in disbonded aluminum honeycomb panels using single degree-of-freedom models

摘要: Prior work on a disbonded aluminum honeycomb panel showed evidence of quadratic stiffness nonlinearity, as well the presence an unknown cubic nonlinearity. Approximations to higher order nonlinear single degree freedom (SDOF) models were solved using method multiple scales. These approximations then used fit displacement data from sinusoidal excitation test and determine coefficients model function damage size. Confirmation nonlinearity was achieved through examination force restoration curves excited at one-half primary resonance in conjunction with coefficient fitting model. The against whether could be or damping related. shows that is This confirmed what seen when system one-third resonance. ability match vibratory behavior SDOF use frequency lower frequencies can isolate damaged area identify mechanisms may involved.