Design and thermal analysis of a cooling system for an innovative braking system using CFD

The Zero-Emissions Driving System (ZEDS), equipped with a Magnetorheological (MR) brake, is a transformative approach to braking systems in automotive technology. MR brakes leverage the unique properties of Magnetorheological Fluids (MRF) to provide controlled braking without relying on friction, thus eliminating particulate emissions and reducing wear. However, a significant challenge faced by this system is the high heat generation during intensive braking maneuvers. Excessive heat can compromise the operational integrity of MRF, necessitating advanced cooling strategies to maintain safe and efficient functionality. Liquid cooling is considered the optimum cooling method for our case due to the high power heat generation of MRF during braking. Rotor and Stator are the two parts where liquid cooling can be implemented. The simulations are conducted in ANSYS FLUENT 2024 R1. with rotor cooling system , the temperature of the MRF at the end of the third cycle is lower compared to the case without cooling. However, the temperature is still near the limitation point of the MRF, which poses a significant risk. If the temperature continues to rise, which would compromise the performance and reliability of the system, potentially causing a malfunction. One reason the MRF temperature doesn't decrease, even with liquid cooling inside the rotor, is that the stator temperature remains high. Stator cooling indicates a notable reduction in stator temperature by approximately 20 to 25 degrees Celsius with respect to the rotor cooling, but the temperature within the MRF remained high. This persistent heat is attributed to the accumulation within the inner components of the rotor, which are somewhat isolated. These results clearly demonstrate that a combined cooling approach, integrating both rotor and stator cooling, is the most effective solution. This integrated strategy not only cools the stator but also facilitates the heat dissipation from the rotor and its inner components, thereby preventing dangerous thermal accumulation.