Unsteady Flow Analysis of a Formula Type Open Wheel Race Car in Cornering 2006-01-3661
In this paper we analyze the unsteady flow dynamics of a Formula type race car in turning condition and offer potential design recommendations for it.
In the competitive world of motorsports, performance in cornering is of vital importance. A vehicle in turning is subjected to highly unsteady aerodynamic forces, which affect vehicle stability and control. Hence its competitiveness is influenced adversely. In a steady flow solution typical of most CFD solvers, periodic flow structures driving the aero-forces are evened out. Hence with such data, one can obtain very limited insight for design improvements. We address this problem by using PowerFLOW, which provides a truly unsteady flow solution. The obtained time series data, allows us to visualize the flow events in real time as well as apply spectral methods to identify vehicle geometry components that drive these events.
This paper presents an initial validation study comparing flow simulation results to track test data for a full scale model in no-yaw condition. Then the effect of cornering on unsteady flow structures is studied using data obtained from simulations with a fixed crosswind and steering angle. Primary focus is given to the study of flow interactions between front tires, front wing, end-plate and the ground. The effect of unsteady flow structures on the rear wing is also demonstrated. Ultimately the study provides insight into the flow structures driving the aero-loads on the main lifting and control surfaces in turn condition. With this insight, some design recommendations are made and supported with additional simulations.