Construction and Evaluation of a Scale Model of The Chalmers Formula Student Car

Abstract

In Formula Student competitions, small improvements in aerodynamic performance can have a decisive impact on overall vehicle competitiveness. The aim of this project was to 3D-print a modular scale model of the Chalmers Formula Student car, enabling aerodynamic evaluation of a few design configurations in both computational and experimental environments. The original vehicle geometry was simplified in CAD to simplify manufacturing and ensure feasibility of scale-model testing. Non-critical features were removed while preserving the main aerodynamic surfaces responsible for downforce and drag generation. The resulting modular model allowed systematic variation of key aerodynamic components across different configurations. Computational fluid dynamics (CFD) simulations were conducted using STARCCM+, where aerodynamic forces and properties were evaluated for each configuration. The same configurations were tested experimentally in the Chalmers wind tunnel to enable comparison and validation of the numerical results. The results showed consistent discrepancies between CFD and wind tunnel measurements, with CFD generally predicting higher values of both drag and downforce. Despite these differences in absolute values, the relative trends between configurations were largely consistent, indicating that CFD could still be used effectively for comparative design studies. The observed discrepancies are primarily attributed to differences in setup between the numerical and experimental environments, including boundary condition simplifications, surface quality of the printed model, and experimental mounting constraints. Overall, the study demonstrates that although CFD requires careful calibration against experimental data, it remains a valuable tool in the aerodynamic development of a Formula Student car. Furthermore, the results highlight that small variations in surface quality and manufacturing tolerances can have a significant influence on the resulting aerodynamic performance, underscoring the sensitivity of scale-model testing.