# Enhancing vehicle performance through the application of airfoils as spoilers with movable trailing edge

## TL;DR

This paper shows how adjustable spoilers on cars can improve performance and stability by dynamically controlling aerodynamic forces.

## Contribution

The novelty lies in using airfoils with movable trailing edges to dynamically adjust downforce and lift forces for vehicle performance.

## Key findings

- Adjusting the trailing edge angle increased negative lift force by up to 36% at 30 degrees.
- Positive lift force improved vehicle acceleration with a 15% increase in total lift force.
- Drag coefficient simulations showed a 6% discrepancy compared to Tesla's reported value.

## Abstract

Vehicle safety and stability are paramount in the automotive industry, with aerodynamics playing a crucial role in enhancing these attributes. Spoilers, often used to modify airflow around vehicles, can significantly impact performance depending on their design and configuration. This study explores the use of airfoils as spoilers with adjustable trailing edges to dynamically control downforce and lift forces, aiming to improve vehicle stability and performance.

Computational Fluid Dynamics (CFD) simulations were performed using ANSYS Fluent ® software (ANSYS, Inc., Canonsburg, PA, USA) The authors confirm that they have obtained the necessary license for the use of this software in academic research. to analyses the aerodynamic effects of spoilers with varying trailing edge angles (AOTE). A Tesla car model was designed in CATIA™ software (Dassault Systèmes), Vélizy-Villacoublay, France), and simulations were conducted at speeds ranging from 120 km/h to 350 km/h. The Shear Stress Transport (SST) k-ω turbulence model was employed to accurately capture airflow patterns. The computational domain was configured as a wind tunnel, and a grid independence study ensured the reliability of the results. Boundary conditions included velocity inlets, pressure outlets, and no-slip walls for the car and spoiler surfaces.

The study revealed that adjusting the trailing edge angle had a significant impact on downforce and lift forces. At a trailing edge angle of 30 degrees, the negative lift force increased by up to 36%, while at zero degrees, it increased by up to 17%. The positive lift force was optimized to enhance vehicle performance during acceleration, resulting in an overall increase in total lift force by up to 15%. The simulated drag coefficient of 0.256 showed a 6% discrepancy compared to Tesla’s reported value of 0.24, primarily due to differences in mesh refinement and the omission of certain design features.

This study demonstrates the potential of movable trailing edge spoilers in improving vehicle stability, handling, and acceleration. The ability to dynamically adjust aerodynamic forces offers a practical solution for enhancing vehicle performance and safety. Future research will focus on refining control algorithms and testing under a broader range of driving conditions. These findings provide a strong foundation for integrating advanced aerodynamic features into modern vehicle designs.