Getting old and forgetfull: flow becomes non-laminar at "x" degree.. 10? 12? 17? - Fuelly Forums

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Old 12-18-2009, 05:16 AM   #1
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Getting old and forgetfull: flow becomes non-laminar at "x" degree.. 10? 12? 17?

I've heard all kinds of numbers over the years, but a while back when posting here I finally figured out what the correct answer is. (I know *it depends* on speed, humidity and elevation, but let's say... really really subsonic, like 65mph, 60% humidity and sea level)

And a ball park is fine, I'm building a rear fairing for a street car, not a fighter jet.
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Old 12-18-2009, 05:22 AM   #2
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When the reynolds number exceeds 3000?
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Old 12-18-2009, 05:31 AM   #3
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Quote:
Originally Posted by bobc455 View Post
When the reynolds number exceeds 3000?
(digging through mental cobwebs)
I *think* that's what I'm talking about.

I remember a rule of thumb for back hatches/fairings that went something like "remember, if the angle is more than "x" degrees and the flow will separate and you'll have turbulence"

But I can't find the dall garned number for "x".
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Old 12-18-2009, 05:57 AM   #4
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It might be in one of these:
http://www.gassavers.org/showthread.php?t=4527
http://www.gassavers.org/showthread.php?t=1298

From:
http://www.google.com/custom?hl=en&c...%3A6eyn0a2-udg
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Old 12-21-2009, 08:59 AM   #5
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The answer to all questions is:
42
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Old 12-21-2009, 09:13 AM   #6
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Old 12-23-2009, 03:54 AM   #7
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Quote:
Originally Posted by rgathright View Post
The answer to all questions is:
42
That's only the answer, they have finished calculations on the question. damn mice.
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Old 12-23-2009, 07:28 PM   #8
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Quote:
Originally Posted by oneinchsidehop View Post
That's only the answer, they have finished calculations on the question. damn mice.
Is that your final answer?
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