Abstract:
This paper investigates the flow-blocking ability of a novel valve-mode magneto-rheological
(MR) device to determine whether it can be used to replace the existing electro-mechanical
solenoid valves that are used to control the semi-active spring characteristics in a four-state,
semi-active vehicle suspension system (called the 4S4 system). MR fluids exhibit a reversible
behavior that is controlled by changing the intensity of an externally applied magnetic field,
allowing a change in the effective viscosity of the fluid. A mathematical model of the
proposed flow-blocking valve has been developed using a combination of the quasi-
Newtonian fluid model and the Bingham plastic model. This model has been modified with
suitable parameters and is used to predict the blocking characteristics of the MR valve. An
experimental setup has been developed with a prototype triple-pass valve mode MR fluid
channel. The experimental results demonstrate that the MR valve designed and developed in
this study is capable of generating a significantly high-pressure drop at very low flow rates,
effectively blocking flow for practical use in the 4S4 system.
