Rivian R1T Aerodynamics - Is the claimed drag coefficient of 0.30 correct?

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Rivian R1T Aerodynamics - Is the claimed drag coefficient of 0.30 correct?

Learn more about CFD simulations:    • Computational Fluid Dynamics Explained  

Rivian claims a drag coefficient of just 0.30 for the Rivian R1T. That's much lower than the typical 0.45-0.50 for cars like the Ford F150 and alike.In this video, we'll goo over the details of how they did this.

--Smooth underfloor--
On a conventional ICE (internal combustion engine) truck, many of the drive train components are exposed. This creates quite a lot of aerodynamic resistance as the air flows underneath the car. On the Rivian, they have covered almost the entire underfloor with flat, smooth panels. This greatly reduces the turbulence & drag generated.

--Smooth exterior--
Door handles have been made flush and the design in general doesn't feature many external bits of geometry sticking out. This helps to keep the flow attached to the surface.

--Air deflectors--
Ahead of both the front & rear wheels, air deflectors help to guide the air around the tires, reducing the "head on collision" of the air on the tires. They likely also help to bridge the wheel well area.

--Air curtain--
Inside the front bumper, air gets accelerated through channels which exit in the front wheel wells. This stream of air acts as an air curtain, shielding the rotating wheels. This reduces the drag generated by the wheels, which typically act as large mixers.

--Air breathers--
A slot/channel connects the rear of the front wheel wells to an open channel at the bottom of the door panels. This helps to evacuate some of the high pressure air in the wheel wells and provides a stream of air that ends up at the rear wheels.

--Cabin spoiler--
The spoiler at the cabin helps to "contract" the flow both in top view and side view. The flow lands onto the closed cargo bed, ahead of the trailing edge of the cargo bay. The spoiler also features slots which help to accelerate the flow / draw more air downward into the wake.

--Gaps--
At the top of the right A-pillar we detected more turbulence than the same area at the left A-pillar. Upon closer inspection, we found that there actually was a misalignment of panels, causing this flow problem.

A massive thanks to A2MAC1 (https://www.a2mac1.com/) for providing us with the 3D scan of the Rivian R1T. Just contact us if you want to purchase this or another analysis using their 3D scans.


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