Constitutive modeling of magnetorheological fluids: A review

Magnetorheological (MR) fluids have been extensively utilized in broad applications in diverse fields because they are characterized by many attractive features, such as high yield strength, low sensitiveness to impurities, wide operating temperature range, and fast response. Constitutive modeling is a very useful tool for characterizing the rheological properties of MR fluids, which plays a significant role in the design and optimization of MR devices. Over the past few decades, many constitutive models have been proposed for MR fluids. This article aims to provide an overview of the constitutive models of MR fluids and the applications of these models in MR device modeling, including quasi-static modeling, dynamic modeling, and finite-element modeling, along with a brief coverage of the constituents and rheological properties of MR fluids. The attention is mainly focused on the macroscopic parametric constitutive models of MR fluids, and a quantitative comparison among them has been conducted by utilizing a series of representative experimental data sets; while the microscopic constitutive models are briefly introduced since they are quantitatively fewer than the macroscopic models due to their inherent complexity in physics and limited applicability in practice. The review also analyzes the gaps in studies on the constitutive modeling of MR fluids, identifies the research directions, and makes suggestions for future development.