Magnetorheological (MR) dampers are semi-active controllable devices that utilize magnetorheological fluids (MRF) for generating governable force. The MR fluid contains magnetic micro-sized/nano-sized iron (Fe) particles, non-magnetic-based fluid, and some additives to mitigate sedimentation and agglomeration. The addition of magnetic nano-sized particles exhibits better sedimentation stability relative to common dispersed additives without affecting the MR effect. MR dampers may be treated as fail-safe as they behave as passive dampers in case of a breakdown of the control mechanism. These dampers are simple in construction, own fewer moving parts, make use of less power, are brisk in response, and mitigate the tolerances. MRF have the special potential to vary dynamic yield stress on the application of a magnetic field and damping force is varied by magnetically varying the rheological characteristics of the fluids. This paper investigates the magnetized field produced in the damper using finite element analysis (FEA) and verified using magnetic circuit theory. A 2D axisymmetric MR damper has been firstly modelled using SolidWorks software and then magnetic field density in MRF space on the application of current has been determined using ANSYS Maxwell software v16. For analytical modeling of the MR damper, a program in “C” language for electromagnetic circuit theory has been used to evaluate the shear stress for the MR damper. The “C” program results and FEA results indicated a small variation of 3.63% in magnetic flux density generated for the current flow of 1 A through the coil and this led to the validation of this study.

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