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Old 06-04-2011, 04:15 PM   #16 (permalink)
aerohead
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Quote:
Originally Posted by khafra View Post
Thanks, aerohead! I thought the relevant figure for the Reynolds Number was the viscosity, 13x that of air. If we can really move the water 833x slower than air for a model of the same size, that's great.

My thought was to ignore the flow imaging and just do a/b testing: Put a scale on the tow rope and see how much drag I get on my car model (or any similar bluff body). Then put on miniature turbolator tape in various locations and see if the scale registers a lighter reading for the same water speed.

Then, rig up a waterproof stepper motor to a spoiler and maybe a pump to test the devices in this crazy-looking Chrysler patent: Motor vehicle with flow-influencing devices to reduce air resistance - US Patent 6378932 Description
khafra,you're correct about the Reynolds number.Kinematic viscosity is the operative parameter on that one.I do have an SAE paper on underwater tow-testing of 1:24-scale Formula-1 models and they're size was not an issue.Which is great as far as model making goes.
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