Sensitivity of Aerodynamic Force Coefficients to Changes in Onflow Velocity Components for a 1/4 Scale Automobile Model

Abstract

Finding a reliable and accurate numerical model to investigate the transient effects of external turbulent flow on vehicle performance is of interest to the automotive industry. Practical applications include the assessment of vehicle wakes and/or over-taking manoeuvres on vehicle aerodynamic forces. On-road measurements are expensive and repeatability of test conditions can be difficult to achieve in practise. Schröck et al. [1] suggests that aerodynamic forces acting on a vehicle are sensitive to side wind conditions and showed that a transferfunction approach could be used to predict the influence on vehicle aerodynamic loading. The current work aims to compliment the work of Schröck et al. by utilizing both experimental and CFD to investigate the influence of time varying on-flow conditions on the drag for a 1:4 scale model vehicle. Outcomes of this work might then be used in development of accurate and cost effective prediction methods.