55 / 2021-03-29 09:09:48

Vibration characteristics of a rotating drum partially coated with strain-depended hard coatings

Drum; rotation effects; hard coatings; strain-depended behaviour; region division method

By considering the strain-depended behaviour of hard coatings, a unified nonlinear modelling method is proposed to build the semi-analytical model of a rotating drum partially coated with the coatings. The material damping is considered by using the complex modulus method. And to ensure the precise introduction of the strain-depended behaviour, cubic polynomials are used to represent the relationship between the storage and loss moduli of the coatings and the stain of the drum. Moreover, the rotation effects (initial hoop tension, centrifugal force, Coriolis force) are introduced, and the equation of motion is built by utilizing the Sanders’ shell theory and Rayleigh-Ritz method. Based on a region division method, the hard-coated layer is divided into many regions. The equivalent strain of each region is represented by the stiffness matrix of the region and displacement coefficient vector, and then the strain-depended behaviour of coatings is further introduced into the equation of motion. By separating the real part and imaginary part of the equation, an efficient iterative algorithm is presented for solving the complex nonlinear equation of motion. The convergence analysis and comparison investigation are performed to verify the presented method. Furthermore, the influence of both the position and area of coatings on the nonlinear vibration is evaluated, and better vibration-reduction schemes based on the coatings is proposed.