Research on a novel water-cooling multi-cylinder magnetorheological transmission device

Power transmission is an important application for magnetorheological (MR) fluid, and the cylinder-type power transmission device is a novel transmission form due to its high stability, higher transmission torque, and large ratio of power to mass. This work designed a novel multi-cylinder transmission device with a water-cooling channel because the MR transmission device, especially high-power MR transmission device, inevitably works in the high-temperature environment. Based on Ohm's law and electromagnetism theory, the magnetic circuit in the novel MR transmission device is designed, and the magnetoresistance was calculated. The finite element method is used to analyze the magnetic field in the device to ensure that the magnetic field in the working gap of MR fluid is strong enough for the MR effects. The temperature of the MR fluid inside the device is analyzed by the finite element method in the natural cooling state and the water-cooling state, respectively, so as to obtain the performance of water cooling. The novel MR transmission device is manufactured to verify its power transmission capability and heat-dissipation performance. The experimental results show that the novel device can transmit a maximum torque of 70 N m, consistent with the rated torque. In addition, compared with natural cooling, the water cooling makes the temperature of the MR fluid to drop by 32.7% under the same working condition. This is the first time that the cooling channel is set up in the cylinder-type MR transmission device, which will provide a solution for the higher power transmission capacity by MR fluid.