Fans and critics alike panned last week’s Cybertruck unveiling, calling the design boxy and ugly. One specific area of concern that was not addressed by Elon Musk was how aerodynamic the new design was, something that is particularly important for electric vehicles.
Engineer Justin Martin has attempted to answer that question, by taking a user-created (i.e., non-Tesla) 3D design and uploading it into a virtual wind tunnel. Obviously since this 3D model was created only by reviewing photos and videos of the truck, the results aren’t going to be 100% accurate, but certainly give a sense to the aerodynamic efficiency of the Cybertruck.
And the results were better than expected. One of the main concerns before running the simulation was what effect the sharp, angular windshield would have on aerodynamics when there is a big empty void, the “Vault”, behind it. On typical pick-up trucks, this area is well known for turbulence, as the airflow goes over the truck cab and into and over the box. The fear was the angular windshield would result in airflow detaching from the truck, in other words continuing up at the same angle, away from the truck bed.
The results showed the Cybertruck’s design actually works well to maintain a flow over the top of the car without detaching as feared. These results depend on the roundness applied at these edges in the final production model, which can’t be accurately determined from pictures alone.
While Martin didn’t attempt to calculate a drag coefficient, Wouter Remmerie, an Aerodynamics & CFD specialist, did attempt to calculate one for the Cybertruck. The drag coefficient is typically used as a rough estimation of how efficient a car is as it moves forward through air. The lower the number, the more efficient the car.
One of the difficulties in estimating one currently without a full 3D model from Tesla directly is the wheel arches and fenders. The large open wheel arches and protruding fenders don’t help with the aerodynamics, as they create quite a bit of drag themselves, according to Remmerie.
Using the best information available today, he calculate the drag coefficient Cd to be 0.48 (if you’re interested, you can download the full report here). For comparison, the drag coefficient for the Model 3 is 0.23.
As mentioned, these results are obviously very preliminary as they were built on public 3D models based on pictures and videos of the Cybertruck. Until we get official numbers and designs from Tesla, we won’t know for sure just how aerodynamic Tesla’s Cybertruck really is. But this certainly points out both some positive areas where the Cybertruck performs well, and others where improvement is still needed to improve efficiency. Good thing Tesla still has two years to tweak it.