As we wanted to test our car design iterations before we mill and make them and waste time on unreasonable ideas, we put our ideas through a Computational Fluid Dynamics (CFD) software. This allowed us to see where there was high and low pressure, laminar and turbulent flow and attachment and separation. These critical characteristics will decide what car design is fast or not this is why it was such a crucial part of our design phase.
The blue either represents slow airflow (or the actual body of the component). Blue appears just behind the body of the car in the bottom left image. This is due to the diffraction of the fluid (air) around the edge created when we (digitally) temporarily removed the back of the car, to reduce the number of unnecessary polygons in the simulation. This speeds up the processing of the CFD simulation. There is also a blue area in between the wheel and front wing – this will be completely negated when the wheels are turning.
The front wing creates vortexes that hug the side of the car, similarly to the cars in F1. This creates a layer in between (1) The laminar flow of air over the car and (2) The turbulent air in the environment. A secondary reason for the wing overhanging the side of the wheels – If not, these vortex created to help the car, will instead ruin the air flow over the car itself, slowing it down. Finally, the overhang also helps push the air around the side of the wheels, reducing drag.
It was difficult to retain the air flow sticking to the surface of the wing. As a result, the design being used is the maximum angle of attack possible with as small a size as possible. This angle is however enough to kick the air up over the wheels while keeping the wing light and within regulations.
All of this hard work and testing is what led us to having the fastest car at the regional finals. The painstaking iterating paid off and left us extremely happy with the result.
We kept iterating and researching after regionals ready for nationals – find out more