An Improved Model for Magnetorheological Fluid-Based Actuators and Sensors

Abstract

The resistance to flow of magnetorheological (MR) fluids is greatly increased by the application of a magnetic field. At present, most devices exploiting this MR fluid behavior are pistons executing straight-line motion. The MR fluids in these devices are subjected to shear flow, and are modeled by either the Bingham plastic or Herschel-Buckley models, both 1D, phenomenological continuum-level forms relating strain rate, magnetic field magnitude, and stress magnitude, and fit to continuum-level empirical measurements. We employ a multiscale model of the MR fluid introduced in an earlier paper, which integrates nanoscale behavior over a mesoscale volume to deduce continuum properties. This approach replaces many of the phenomenological features of the Bingham plastic and Herschel-Buckley models with first principles, and isolates those few phenomenological features that remain into a single scalar term. The model is compared to the Bingham plastic and Herschel-Buckley models, assessing each model’s ability to capture the experimentally measured mechanical response of a particular MR fluid-based damper to specified magnetic fields. The result of this comparison is that, our model possesses the flexibility to best match the measured behavior of the MR fluid device observed in our experiments, with fewer required experimental measurements.

A review on the simulation and modeling of magnetorheological fluids

“…All models in this approach are macro-scale and consider the MR suspension as a single continuum. The continuum approach suffers from some weaknesses; the rheological constants are derived from fitting the experimental measurements, consequently their application is limited to a narrow range of applicability (Ahmadkhanlou et al, 2010). Most of the rheological models are almost inaccurate at low values of stress because of assuming a strict yield stress.…”

The chemical stability and cytotoxicity of carbonyl iron particles grafted with poly(glycidyl methacrylate) and the magnetorheological activity of their suspensions

“…Compact coating of PGMA largely improved the chemical stability of the particles in an acid environment and thus reduced the common drawback of bare CI particles. Therefore some authors [21][22][23] have employed the All chemicals were used as received. The cell viability was evaluated by spectrometric assay (MTT).…”

“…The behavior of MR suspensions can be characterized by the Bingham plastic model [19], which belongs among the most popular models because of its simplicity and sufficient accuracy [20]. Therefore some authors [21][22][23] have employed the All chemicals were used as received. Therefore some authors [21][22][23] have employed the All chemicals were used as received.…”

Study of limit cycle in antagonistically coupled Magneto-Rheological actuators

“…Fig. 3 shows the shear stress-shear rate behavior of a sample MR fluid, which qualitatively represents the typical behavior of MR fluids [15]. As observed, the behavior of an MR fluid can be divided into two main phases; preyielding and post-yielding regions.…”