VARIABLE INERTIA DAMPER USING MR FLUID

Inertia damper has an inertia effect by a flywheel which is caused by a quick moving mass. In general, it is difficult to change the inertia mass physically. In order to obtain a variable inertia effect, a new type of inertia damper has a long bypass pipe is proposed in this paper. This type of damper generates a damping effect and inertia effect by the fluid. It is noted that the inertia effect is depended on a density of the fluid, cross sectional areas of cylinder and bypass pipe, and length of the bypass pipe. If the diameter of the bypass pipe can be controlled, it means that a cross sectional area of the bypass pipe can be switched by clustering particles of MR fluid under magnetization, the inertia effect might be artificially controllable. A trial damper with several electromagnets installed along the long bypass pipe is manufactured, and dynamic property is measured when MR fluid inside the bypass pipe is magnetized by the electromagnets. From experimental results, it seems to be that the inertia effect can be switched and depended on amplitude of magnetization. Finally, the calculated results are theoretically approached, and compared with the experimental results.