Numerical Investigations on Thermo-Structural Behavior of Various Cut Patterns for Ventilation on Automobile Brake Discs

Overheating of the brake disc is a major concern in the brake performance. Overheating is the main cause of a reduction in braking efficiency, especially if a vehicle is fully loaded. The heat dissipation rate for Solid rotors is very low. In order to increase the heat dissipation rate, the disc must be used with ventilation provided on it. Further in ventilated disc rotors, the ribs in between the rotors provide cooling. The ribs allow the flow of heat and pull out the air in between the rotors for efficient cooling. In this research, four different brake disc namely, Solid Disc (SL), Cross-drilled disc (CD), Cross-slot disc (CS) and Hybrid disc (CD-CS-SG) which is a combination of Cross drilled and slot with side groove have been analyzed at various brake conditions in the form of heat generation and thermal stresses. The temperature gradient over the surface is studied using the thermal numerical simulations and the stress generated within the structure core of hybrid rotor is studied using the thermo-structural coupling. These results of the optimized hybrid rotor are compared with the results of the primitive design of solid, cross-slotted and curved vane ventilated disc rotors. The results when compared at a given constant angular velocity, the hybrid ventilated brake disc rotor with a side groove proves to be superior to the primitive types in mechanical and thermal properties. It is also been observed that the disc surface temperature was increased with an increase in braking time. Whereas, heat dissipation was found to be maximum in the hybrid brake disc as compared to all configurations. More thermal stresses were observed in hybrid brake disc especially at the corners as compared to solid disc.