The Effect of Rear Spoiler Type, Velocity, and Distance between Two Cars in a Slipstream on the Force of Drag on the Trailing Car

The purpose of this research was to determine which combination of factors, rear spoiler type, velocity of the two cars, and distance between the two cars, would experience the least amount of drag force on the trailing car in a slipstream. The subject of drag force is important in the scientific and automobile communities, as advances in the field of aerodynamic forces can lead to many benefits to many people and industries, including more efficient methods of optimizing fuel consumption, and in the case of the stock car racing industry, more efficient methods of overtaking opponents in a race.

In order to collect data, two styrofoam cars were built and tested with corresponding rear spoiler type, velocity of the wind tunnel, and distance between the two cars. The drag force acting on the trailing car was measured with a force sensor. The data collected was then analyzed via a Three-Factor Design of Experiment statistical analysis. The results of this analysis and scientific reasoning confirmed that the significant factors of this experiment were velocity and distance between the two cars, while rear spoiler type was deemed as an insignificant effect to the overall force of drag acting on the rear car. As velocity decreases, drag force decreases and as distance decreases, drag force also decreases. Not only did these results provide reasoning to accept the hypothesis of the experiment, but it also affirms previous scientific research conducted in the subject of aerodynamic forces and the effects of a slipstream.

Research Conducted By:

Yusuf Khatri
Sterling Heights High School

Stephen Lewandowski
Sterling Heights High School