Coupling and simulation analysis of magnetorheological fluid damper based on dynamic grid

Abstract A coupling simulation analysis method for the damper, considering structure, magnetic field, and fluid flow, is proposed based on a double-rod external valve magnetorheological fluid(MRF) damper using dynamic mesh technology. First, the overall structural parameters and principle of the double-rod external valve magnetorheological fluid damper are analyzed to determine the unidirectional and multi-stage circumferential flow layout in the external valve, along with the magnetic field configuration perpendicular to the circumferential channels. Next, based on magnetic circuit design and steady-state finite element analysis, the relationship between the magnetorheological fluid viscosity, magnetic flux density, and external excitation current in the channels is clarified. The relationship between the fluid viscosity, pressure drop, and flow rate is then analyzed. Finally, a complete dynamic mesh model for the fluid domain is established to compute the coupled dynamic damping characteristics under piston motion conditions. The results demonstrate that the coupling simulation analysis method can effectively calculate dynamic damping forces under piston speed excitation and external electrical excitation.