Supachai Lakkam, Kullayot Suwantaroj, Phupoom Puangcharoenchai, Songwut Mongkonlerdmanee, and Saiprasit Koetniyom

pp. 671 - 781

Abstract

A brake disc plays an important role in the automotive industry since it concerns directly with safety. In order to
develop proper heat ventilation a wide range of brake discs have been designed. Different types of physical brake disc
geometries, as front- and back-vented brake discs, affect the heat ventilation directly. This is a vital factor of the brake’s
capability. We recognized the importance of this circumstance and therefore attempted to create a test to investigate the
temperature gradient of the brake disc in order to evaluate the coefficients of heat convection. The coefficients were modified
by the change of temperature distribution in both brake discs under the forced heat convection in steady state conditions.
However, the heat radiation value does not take into account that the heat convection is dominated by the physical geometry
of the brake disc. To set up the experimental test for investigating the heat transfer by convection the JASO C406 standard is
adopted. The experimental results in terms of heat convection coefficients are used in the numerical simulation via the finite
element method in order to study the temperature diffusion and heat ventilation of front and back-vented brake discs. Consequently, the experimental results reveal that the overall heat convection coefficients of the front-vented brake disc are higher
than these of the back-vented one. In other words the simulation yields that the front-vented brake disc allows stronger heat
ventilation than its compared object, leading to larger temperature differences between outboard and inboard rotors, resulting
in more thermal stress. This makes it more susceptible to be damaged during operation.