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Modern vehicles have been increasingly equipped with advanced technologies such as hybrid and cylinder-on-demand to
enhance fuel efficiency. These technologies also come with vibration problems due to the switching between the power
sources or the variation of the number of active cylinders. To mitigate these vibrations, a large variety of vibration
isolators have been proposed, ranging from passive to active isolators. Semi-active mounts are often preferred to other
solutions because of their overall low power requirement in operation as well as relatively simpler configurations.
Among the semi-active categories, the magnetorheological fluid (MRF) mounts have been proven to be a viable solution
for modern vehicle vibration isolation. These mounts can change their stiffness and damping characteristic without
involving moving parts, by controlling the yield stress of the MRF housed inside the mount by means of magnetic field.
This study looked into several innovative designs for MRF mounts. The characteristics of the mount depend significantly
on the compliances of the rubber, the number and arrangement of the fluid chambers and the number of flow passages
connecting the chambers. These parameters provide the designers with various options to design the mounts to function
in various conditions and over a wide range of frequencies. Different values of the aforementioned parameters were
selected to form specific designs with certain characteristics. Mathematical models have been developed for each design
and MATLAB/Simulink was used to simulate the response of each mount to certain excitations. As the hydraulic and
magnetorheological (MR) effects are dominant in the mount, the elastomer behavior is considered linear.
A discussion of the advantages and disadvantages of each design, based on the simulated response, is presented. The outcomes of this study can be a useful reference for MRF mount designers and leads to the development of a general MRF mount design methodology.
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