Numerical Study of Brake Disc Cooling Accounting for Both Aerodynamic Drag Force and Cooling Efficiency 2001-01-0948
This paper reports how numerical simulation can be used as a tool to guide vehicle design with respect to brake cooling demands. Detailed simulations of different brake cooling concepts are compared with experimental results.
The paper consists of two parts. The first part places the emphasis on how to model the flow inside and around the brake disc. The boundary layer and the pumping effect is investigated for a ventilated single rotor. The numerical results will be compared to experimental results. In the second part, an engineering approach is applied in order to rank different technical solutions on a Volvo S80 vehicle in terms of brake cooling and aerodynamic drag.
The results from the free brake disc simulations indicate that the tangential velocity can be predicted with high accuracy, e.g. standard k-ε model with prism near wall cells typically within 4% of measured data. The pumping effect, i.e. the radial velocity was somewhat poorly predicted, although within 15% using standard k-ε model.
On the complete vehicle simulations, trends for both aerodynamic drag and brake cooling were captured for the cases considered. This implies that CFD is a useful tool in evaluating different brake cooling design concepts.