Vibration suppression device that has variable moment of inertia using magneto-rheological fluid (Fluid behavior inside flywheel)

Abstract

The authors developed a vibration suppression device (VSD) that has variable moment of inertia using magneto-rheological (MR) fluid in order to get series inertia mass effect for vibration reduction. In previous paper, the proto-type VSD was manufactured and the variable series inertia mass effect was confirmed. From the experimental results, the series inertia mass effect can be switched by the current of electromagnets. And theoretical model of solidified form of the fluid was proposed by formula and the trend were closed the experimental results. Then the vibration tests of 1DOF system with the VSD were conducted by a shaking table. Vibration reduction of the VSD was confirmed. The current of the electromagnet was controlled by using the reinforcement learning. But the fluid behavior inside the flywheel has not investigated before. In this paper, to investigate the fluid behavior inside the flywheel, it is analyzed by computational fluid dynamics (CFD). Three types of the flywheels are manufactured, and 2 types of electromagnets are used here. Equivalent inertia mass in totally 20 cases of the flywheel and the electromagnets are numerically calculated by using the OpenFOAM, and also measured in experiments. From the analytical results, convection is initially occurred in the direction of the magnetic poles when the magnetic field applies, and then the particles are eventually solidified at locations other than near the magnetic poles. Finally, the analytical results are compared with the theoretical and the experimental results.

Keywords

• vibration control device
• inertia mass
• moment of inertia
• mr fluid
• fluid behavior
• cfd