Modified Modal Strain Energy Method for Analyzing the Dynamic Damping Behavior of Constrained Viscoelastic Structures

Modal strain energy (MSE) method is an efficient approximation approach for kinetics parameter calculation of constrained viscoelastic structures.MSE fails to determine the precise dynamic behavior of viscoelastic structures when the stiffness matrix is a complex one.To address this issue, this study proposes a new modified MSE method to calculate the loss factor and natural frequency of a constrained viscoelastic structure on the basis of the correlation analysis of the current modal strain method.The modifying factor changed with the amplitude of the modal order loss factor.A prototype system with four parameters, which was equivalent to a viscoelastic sandwich beam or plate, was used to analyze the error between the new modified method and current methods.The proposed method was applied to a viscoelastic suspension.Results show that the proposed method obtains minimum relative errors of 1.2% and 2.3% for structural loss factor and natural frequency as compared with existing methods.This study provides a certain reference for the performance analysis, structural design, and improvement of constrained viscoelastic structures.