DIY Aerodynamics #1: a '70s VW Beetle

In this video, we will be doing High Tech aerodynamic field testing do it yourself style. We took a 1970s beetle and equipped it with little tufts. Tufts Tufts are small bits of light-weight wire that can move along with the wind. They allow you to see the local orientation of the air flow. If they stay still and stick to the surface, this indicates nicely attached air flow. If they wiggle around in different directions, this indicates turbulence, often occuring in zones of detached air flow. Testing on a '70s volkswagen beetle We equiped the roof and rear window of a 1970 volkswagen beetle with tufts, all around 10 cm apart. We're curious to learn whether the air flow will nicely follow the curvature of roof and rear window, or detach and become turbulent at a certain point. Observations - Front section of the roof: at the very front of the roof, just after the jump from the front wind shield, we saw a slightly more nervous movement of the first tuft. Admittedly, the effect was not very pronounced. The other tufts further down stream were all stable. - Rear section of the roof: all tufts on the roof stayed nicely flat and stable. - Rear window: intense, nervous movement of the tufts Interpretation We saw that at the front of the car, we had a little bit of turbulence at the first tuft. This could indicate detachment of the airflow, possibly because the flow needs to rise up and jump on to the roof. The sharp angle between front wind shield and the top of the roof could cause local detachment of the air flow. Right after that first part, the flow re-attaches again and all tufts are stable until it reaches the rear window: likely, the downward angle of the rear window is too steep for the flow to stay attached. The air detaches and follows a more horizontal trajectory, somewhere above the rear window, causing flow recirculation in the area below. With special thanks to - My dad, for being the best Go Pro Mount alternative in the market - https://www.bensound.com/ for providing us with royalty free music that's easier to listen to than just wind. ----------------------------------------------------------------------------------------------------------- Wouter Remmerie Wouter is the Founder of AirShaper, an online, virtual wind tunnel. With this tool and these videos, we want to make aerodynamics accessible to everyone! Interested in more content like this on the field of aerodynamics? Make sure to click that subscribe button, we post new videos every week! Looking for a way to test your Aerodynamics projects without all the hassle and the huge costs coming with it? Check out https://www.AirShaper.com and see how easy it can be!

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