Each wire is labelled and clear heat shrink used.

UAS has recently begun using Computational Fluid Dynamics (CFD) software to aid us in designing elements of our aerodynamics package.

Unfortunately time and cost constraints make a true to life simulation a difficult task to achieve, as ideally every component down to the smallest washer should be modeled into the software and then animated to garner accurate results.

The UAS rear wing is a fantastic example of how we use the software to aid our design despite our time constraints. By focusing on a small area in isolation, we can more clearly judge how changes will impact our drag and down force characteristics.

In this instance it was found that adding a 15mm gurney strip to the larger lower rear wing increased the overall down force by a significant amount ( ≈ 11%). This produces an extra 14kg of effective weight on the rear at 200kph, with only ≈3% increase in total rear wing drag.

We have also been able to generate numerical data using the program. Doing so allowed us to find a number of interesting results.

On straights, the wear wing of the UAS Zed has a tendency to flex under the down force load. This change in area has an impact on the overall down force of the wing.

Using CFD analysis we were able to simulate a number of different instances. We simulated a straight wing, one with the top wing flexing to touch the lower and an instance of both flexing to the same degree. We did this at both 200km/h and 100km/h simulating a worst case scenario through high and low speed corners.

As can be seen from the tabulated data this flexing causes a drastic change in the dynamics of the wing. Both down force and drag are significantly reduced as the wing starts to bend.

On straights this is beneficial as it has the same effect as the adjustable rear wing systems used in the 2011 formula 1 season, if to a lesser degree, reducing drag so we can achieve a higher top speed.

In low speed areas it is slightly more detrimental, however it should be noted that at these speeds overall down force is significantly lower and as such flex is reduced causing a corresponding reduction in overall down force lost.

The new VQ30DETT motor compared to the old VG30DETT.

The new motor is running less boost and is on E85 while the VG is running more boost and octane booster.

We added a second layer to rear diffuser acting as a scoop for air going under the car. This added 10kg to downforce at 150kmph according to CFD annalysis.

Custom box housing dry sump tank with breather and electric power steering pump, all mounted in the left rear of the car for better weight distribution.

Nascar anti heat and anti scatter blanket of the tunnel.

Garrett compressor cover coarse casting.

Machined lighter and smoother for airflow, with pressed fit and swaged 3inch alloy pipe stepping up from 2.5inch to match our ram pods.

Gurney added to trailing edge of bonnet. Creates low pressure area behind behind it drawing hot air and excess pressure from under the bonnet up and over the car.

This causes a pressure differential increasing down force, improves cooling and feeds more air to our rear wing.

Speed by Time graph taken from Drift box GPS data.

G Force Graph.

Wakefield track map created from Performance Box, GPS positioning.