Wind Tunnel air flow
Hi,
I'm building a small, low-speed wind tunnel to test our school's Greenpower race car designs.
Greenpower has come up on Ecomodder before I believe, it essentially involves single seat electric cars having to travel the furthest distance they can in a given time on one set of batteries. All cars use the same batteries and motor.
Anyway, I digress.
We have built the test section of a wind tunnel for 1/10th scale models of our car designs.
It measures 165 x 235 x 360mm internally, with pieces angled at 45 degrees stretching 31mm along each side from the corner to prevent pressure differences.
The largest model that it could be used for measures 120 x 120 x 280mm however typical sizes are usually about 60 x 50 x 280mm.
The wind tunnel needs to be able to produce speeds from about 25mph to 55mph or so.
I am yet to build the inlet horn, diffuser or purchase any fans yet because I didn't want to build them incorrectly so as to change the working speeds, rendering our wind tunnel almost useless to us.
What size should the inlet horn and diffuser be?
What CFM will I need to achieve these speeds?
If any of you can point me in the correct direction to find answers to either of these questions that would be great.
Thanks
Sam
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