Design of a squeeze film magnetorheological brake considering compression enhanced shear yield stress of magnetorheological fluid

Abstract

A magnetorheological brake, consisting of rotating disks immersed in a MR fluid and enclosed in an electromagnet, is proposed to replace the conventional heavy weight low response hydraulic disk brake. The frictional characteristics of the proposed brake can be controlled by regulating the yield stress of the MR fluid as function of magnetic field and normal compressive force. The controllable yield stress retards the surfaces of rotating disks, thus MR fluid can be used as a brake lining material. The present research work attempts designing a squeeze film MR brake by accounting compression enhanced shear yield stress of magnetorheological fluid. Theoretical calculations indicate that the estimated braking torque of the six plate squeeze film MR brake, under compression, is in the order of 600Nm. To validate the theoretical design and its findings, a prototype of single-plate squeeze film MR disk brake has been developed. Experimental test setup helps to illustrate braking torque under different control currents (0.0 to 1.25 A).

Experimental investigations and characterization of shear and squeeze mode magnetorheological brake

“…Analytical expressions [Eqs. (5) and (6)] used for the same are [20] where is the viscosity of the MRF, is the angular velocity of the disk brake, r 2 and r 1 are outer and inner radii of the rotary disk of the brake, h is the MR fluid gap, N is number of turns in electromagnet, I is input current to the electromagnet, k and are MRF-dependent constant parameters. Equation (5) is used for evaluation of shear mode MR brake, while Eq.…”

“…Thus, there lies need to explore squeeze mode MR brake regarding output torque and temperature rise. Sarkar and Hirani [19,20] have explored this mode and reported improvement in the output torque. The present work reports the design and development of shear and squeeze mode MR brake prototype.…”

Simulation-based estimation of an automotive magnetorheological brake system performance

“…The results of the FEA based optimization, taking into account the mass, space, braking torque, and temperature, were presented. Sarkar and Hirani [11] proposed a squeeze mode-based MR brake to improve the braking torque. During the experimentation, a maximum torque of 7 Nm was achieved at 1.25 A, which is not sufficient for an automotive application.…”

Performance Simulation Analysis for Magnetorheological Damper with Internal Meandering Flow Valve

“…Furthermore, the stiffness of MR fluid can be varied by controlling the magnetic field strength. MR fluid has been applied in numerous automotive components such as vehicle clutch, braking, steering, suspension, clutch, and engine mounting system [11][12][13][14][15]. One of the well-known devices that employ MR fluid is Magnetorheological (MR) damper [16][17][18].…”