Analysis Of The Dynamic Characteristics And Damping Properties Of3-Dimensional Periodic Flexible Structures

Nowadays, with the rapid development of modern society and technology, people have more stringent requirements for material properties. The multi-performance composite materials, which have excellent properties including light weight, high stiffness, shock absorption and reduction, have been paid more and more attentions.3-dimensional periodic flexible structure is a new type of damping structures aiming at vibration absorption in the low frequency range. The structures, which are made by adding mechanical scaffolds or filling damping liquid between the two layer sheets of the unit cell, are devisable structures with good damping properties. Therefore they have a broad application prospect in the navigation, vehicle, construction and other fields. In this paper, two types of periodic flexible structures are researched. First of all, we analyzed the dynamic characteristic and damping property of the periodic flexible structure with damping liquid and micro-perforated panel. And then, the dynamic characteristic and damping property of the periodic flexible structure with mechanical scaffolds were researched. The main contents and conclusions include:For the first structure, the cell of the periodic structure was firstly analyzed by using the Newton’s Second Law and the invariable property of incompressible liquid in this article. Secondly, according to its mathematical models, an analytical method was programmed in MATLAB. Finally, by means of modification of structure size parameters and dynamic analysis of the structure as well as the curve fitting technology, the relational expression between the structure size parameters and the transfer function was summarized, the dynamic characteristics of the structures can also be designed by utilizing these formulae. Furthermore, the damping property of the flexible structure was also researched. It shows that the structure with damping have excellent effect on the shock absorption.For the second structure, based on the shock theoretical and physical meaning of transfer function, the influence of the model size parameters on the dynamic property and the damping property is researched. And then, by modifying the size parameters, the analysis of FEM model is simulated and the dynamic characteristics curves are also fitted. Finally, the relationship between the coefficients of the transfer functions and the size parameters of the model is derived.All in all, dynamic characteristics and damping properties of the two periodic flexible structures are investigated through numerical calculation and simulation.