INVESTIGATION INTO TEMPERATURES, THERMAL STRESSES AND DEFLECTIONS OF DIFFERENT BRAKE DISC DESIGNS FOR COMMERCIAL VEHICLES

摘要

The paper investigates temperatures, thermal stresses and deflections of most commonly used brake disc designs for commercial vehicles. Two types of ventilated disc designs (standard and anti-coning) and a solid disc design w ere analysed. The braking duties considered include single stop and a long drag braking. The difference between the two ventilated disc designs relates to the attachment of a disc friction 'ring' (cheek) to the top hat section. The outboard disc friction surface is attached to the top hat section in a standard disc, whilst the inboard face is attached to the top hat section of the anti-coning disc. The two ventilated disc designs show very different thermal stresses, deflections and cooling characteristics. The anti-coning design has very low deflections (coning), but higher stresses. Furthermore, this design has much poorer cooling characteristics than standard ventilated disc due to the restricted air intake (from the outboard side of the disc). The studies indicated much better overall performance of the solid disc than originally expected. Despite inferior cooling characteristics, this design has the highest thermal capacity, which is the result of its higher mass. Solid disc has low stresses and deflections (coning). Conducted research clearly shows that there is no 'best overall' design and the selection of the brake disc concept is a complex process which should be 'braking duty driven'.