Analysis on influence of the magnetorheological fluid microstructure on the mechanical properties of magnetorheological dampers

Abstract

Magnetorheological (MR) damper is a semi-active control device designed by utilizing the instantaneous fluid-solid conversion characteristics of MR fluid, thus the microstructure of MR fluid fundamentally determines the mechanical properties of MR dampers. In order to study the influence of MR fluid microstructure on the macroscopic mechanical properties of MR dampers, a micro-macro mathematical model for MR dampers was proposed to describe the dynamic properties of MR dampers affected by the microstructure of MR fluid. Firstly, the micromodel of MR fluid was brought into classic quasi-static model and the double-Sigmoid model to propose a mathematical model, which considers the MR fluid microstructure by expressing the yield force parameter in the traditional double-Sigmoid model with the microstructure parameters of MR fluid. By analyzing the data of the performance test of a single-coil MR damper, the parameters of the proposed mathematical model were fitted. The proposed micro-macro model for MR dampers was verified by comparing the results calculated by this model with the performance test data. Based on the proposed micro-macro mathematical model, the nonlinear hysteretic curves with different MR fluid microstructure parameters can be numerically analyzed and compared. Finally, the influences of the volume fraction, size, and coating thickness of ferromagnetic particles on the mechanical properties of MR dampers were revealed and discussed. The research can provide guidance for the preparation and formulation optimization of high-performance MR fluid.

Bionic Structure Inspired by Tree Frogs to Enhance Damping Performance

“…From the 1960s to the present, throughout the history of MF dampers, researchers have continuously worked to improve their damping performance . To achieve the aim, they have explored various configurations of MF dampers, , added different porous materials into MFs, , and so on. However, little research has been done on the inner surface structures of MF dampers …”

Molecular Dynamics Simulations and Experimental Studies of the Microstructure and Mechanical Properties of a Silicone Oil/Functionalized Ionic Liquid-Based Magnetorheological Fluid

“…This liquid−solid phase transition is reversible, and the mechanical properties of MR fluids are easily managed by adjusting the magnetic field strength. 6,7 Owing to their sensitive and controllable rheological properties, MR fluids have been receiving increasing attention in various mechanical engineering fields, such as those related to shock absorbers, 8,9 dampers, 10,11 and clutches and brakes. 12 However, the density of magnetic particles in these fluids is much higher than that of the carrier liquids.…”

“…Magnetorheological (MR) fluids, which are field-responsive colloidal suspensions of magnetic particles in a nonmagnetic medium, are a special type of smart fluid. , Carbonyl iron (CI) and silicone oil (SO) are commonly used as magnetic materials and carrier liquids, respectively. − Under an applied magnetic field, MR fluids transform from Newtonian fluids into Bingham fluids in milliseconds, and the magnetic particles form chainlike structures along the magnetic field direction. This liquid–solid phase transition is reversible, and the mechanical properties of MR fluids are easily managed by adjusting the magnetic field strength. , Owing to their sensitive and controllable rheological properties, MR fluids have been receiving increasing attention in various mechanical engineering fields, such as those related to shock absorbers, , dampers, , and clutches and brakes . However, the density of magnetic particles in these fluids is much higher than that of the carrier liquids.…”

Investigation of proposed integrated control strategies based on performance and positioning of MR dampers on shaking table

“…Therefore, the research in the field of semi-active control systems has been in focus this last decade. Among the semi-active control device available in the market, magnetorheological (MR) dampers have received great attention from researchers worldwide because of their robustness, adaptability, and distinctive rheological properties [5,6]. The device only requires a small amount of energy to operate, while acting as a passive control device in case of failure of feedback or power supply.…”