Quote:
Originally Posted by CHSGreenpower
Thanks to Sefirob and Aerohead for your input.
Your replies confirm my suspicions that this will only be able to be a visual educational tool for younger students - at that sort of rate it would suck itself in!
I'm a year 10 student, 15 years old, so am still learning here (as you can see). I intend to back up my results with CFD when I have the required experience to do this.
My idea was mainly to use it as an educational tool, and instead of relying on output numbers I was going to use it to answer the question 'does this offer an improvement over that?'
Some people have told me that wind tunnels are near obsolete due to CFD but I know that (like aerohead said) large names in aerodynamic design still use them.
I presume continued use of analogue methods (wind tunnel, water tow) is now mostly to back up CFD readings?
Sefirob - I'd seen that page, and used it a few times, however I came on here to see if:
1. The wind speeds I wanted would work
2. If I could make those speeds accurate by design
The answer, so it seems, to both of those questions is no.
Instead, I now intend to simply make it similarly to the Science Buddies one just as an educational tool.
The question I now ask is: Will the visual outcomes from tests in this (very inaccurate) tunnel mislead students, being a hinderance to their learning?
If so I'll quit while I'm ahead. I've not spent much money on it yet so will probably concentrate on getting my CAD skills up to scratch so I can do CFD instead.
Thanks again
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Daimler-Benz has a full-scale CFD capability which runs on a supercomputer.They report a 99% accuracy compared to full-scale tunnel testing.
The rub is that a single iteration of a body design takes more than a day's run time in the computer.
A full-scale mockup,with interchangeable surfaces in clay can be evaluated within minutes,and changes can also be accomplished within minutes.
Also,clay modelers can actually (and do) modify the clay mockup right inside the wind tunnel,literally shaving a few millimeters off a contour at a time then quickly re-testing.
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I wouldn't discourage you from doing the tunnel.Run as fast an air velocity as your budget can allow.Tell the students the 'conditions' and limitations of the tunnel technology at 1/10-scale,and look forward to more robust 'tools' for the future.
Some 'big dogs' have used 1/10-scale,and they just figure that there'll be a discrepancy from a 'perfect world' condition,but you can certainly see 'trends' with smoke,lamp black and kerosene smears,and tufts.
