Study on dynamics responses and applications of non-uniform beam structure under crosswind

Abstract

This article studies the dynamic responses of the nonuniform beam structure under the action of the crosswind and its applications on vibration control and utilization (energy harvesting based on the piezoelectric beam). First, the natural frequencies and mode shapes of the nonuniform beam are solved by Adomian decomposition method and then the beam vibration deflections and piezoelectric charges are derived. Furthermore, from the theoretical model and solutions, the influences of different taper ratios and outer diameters on the deflections of nonuniform beam structures with the same mass are studied. The deflections of nonuniform same mass beam structures with positive and negative exponential profiles are also compared. It is demonstrated that the deflections of the beam decrease with the increase of taper ratios and increase with the increase of outer diameters. Under the wind velocity ranges of 10 m/s to 26 m/s, the deflection of the nonuniform beam with a negative exponent profile is less than the one with a positive exponent profile. Through this study, the optimal nonuniform beam structure with either small deflection or high piezoelectric charge output can be designed according to different wind velocities and demands.