Experimental measurement of a multi-pole magnetorheological fluid clutch under air cooling

Thermal characteristics have a profound effect on the allowable slip power and torque transmission stability of magnetorheological (MR) fluid devices. This paper investigates the thermal properties of a multi-pole MR clutch under different heat dissipation methods. First, the structure of the clutch is described, and heat generation and heat dissipation of the designed clutch are studied theoretically. Then, a numerical model is established, and several simulations are conducted on steady-state and transient temperatures under various operation conditions. After that, a temperature testing platform for the MR clutch is built, and several temperature experiments are carried out. The results show that the allowable steady-state slip power of the clutch under natural air cooling is about 147 W. Under forced air cooling, the allowable steady-state slip powers are 1.295, 1.555, and 1.790 kW, respectively, when the wind speeds are 3.5, 7.0, and 10.5 m/s. Furthermore, it turned out that the transmission torque of the MR clutch decreases with the increase in temperature. The experimental and simulated values of temperature are in good agreement in terms of numerical values and trends, indicating that the established temperature field simulation model can better reflect the temperature characteristics of the actual operation of the proposed multi-pole MR clutch. This research achievement can provide support for research on heat dissipation technology for MR devices with multiple excitation sources.