Fan placement on a Formula Student vehicle: A study to evaluate placement of fans for improved aerodynamic performance

Abstract

Formula Student 2024 saw an increase in teams that used fans for aerodynamic gain instead of just for cooling purposes. This gave a huge performance to the car in terms of downforce and therefore better grip which allows for faster cornering. The sudden performance gain resulted in a rule change for the 2025 Formula Student season where a maximum combined total rated power of any active devices designed to move air is 500 W. This restriction made it more difficult to find aerodynamic advantages from the fans and their positioning became more vital. The objective for this project is to investigate how a fan system on Chalmers Formula Student’s (CFS) current car can be implemented to enhance the aerodynamic performance. Concepts were generated by dividing the aerodynamic components into four regions, front wing, side wing, rear wing and diffuser. Each component could then be investigated by looking at data from past simulations, but also by taking inspiration from other teams. Having formulated several concepts for each geometrically defined region, they were realized using computer aided design (CAD). The results were then evaluated using computational fluid dynamics (CFD) and numerical values and field plots of several properties were obtained. The result showed that significant downforce can still be found in spite of the new regulation change. The regions that performed best were side wing and diffuser. While the concepts in these regions show potential, future iterative work is still needed to perfect their functionality, depending on the direction of development for the CFS aerodynamic package.