Experimental Works on Dynamic Behavior of Laminated Composite Beam Incorporated with magneto-rheological fluid under Random Excitation

Abstract

Laminated composite structures are widely being used in modern industries particularly robot arms, aerospace and wind turbine blades where the structures mainly exposed to harsh random vibration and in turn, leads to unpredicted failure. Adding Magneto-rheological (MR) fluids in such structures may significantly improve their dynamic response. In the present work, the vibration response of laminated composite beams filled with MR fluids (MR laminated beam) under random loading has been investigated using experimental as well as simulation approaches. Finite Element Model (FEM) has been utilized to simulate the vibration response under random loading. An in-house set-up has been designed to test and investigate the behavior of the laminated beam filled with MR fluid. The simulation results have been validated by experimental ones where a reasonable match has been observed. A mechanical shaker is used to apply a white noise load as input excitation to the beam. Two main common mechanical boundary conditions, namely clamped-free and clamped-clamped boundary conditions have been investigated. The effect of high value (up to 2000 Gauss) of the magnetic field has been investigated. It is observed that increasing the magnetic field up to 1200 Gauss in clamped-free and up to 1500 Gauss in clamped-clamped boundary conditions increases the natural frequency of the structure. Beyond this value, the natural frequencies of some modes decrease. It is realized that by increasing the magnetic field, energy dissipation of MR laminated beam reduced.