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

Click here to see important news regarding the aCar App

Go Back   Fuelly Forums > Fuel Talk > Aerodynamics
Today's Posts Search Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 12-18-2009, 05:16 AM   #1
Registered Member
 
oneinchsidehop's Avatar
 
Join Date: Aug 2007
Posts: 165
Country: United States
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.
__________________

__________________
Mike
_______________________________________________

"If you want to save gas I suggest you permanently remove the drivers seat and steering wheel. That seems to help." -Oscar Halverson

oneinchsidehop is offline   Reply With Quote
Old 12-18-2009, 05:22 AM   #2
Site Team
 
Join Date: Dec 2006
Posts: 659
Country: United States
When the reynolds number exceeds 3000?
__________________

__________________
Think you are saving gas? Prove it by starting a Gas Log, then conduct a proper experiment.
bobc455 is offline   Reply With Quote
Old 12-18-2009, 05:31 AM   #3
Registered Member
 
oneinchsidehop's Avatar
 
Join Date: Aug 2007
Posts: 165
Country: United States
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".
__________________
Mike
_______________________________________________

"If you want to save gas I suggest you permanently remove the drivers seat and steering wheel. That seems to help." -Oscar Halverson

oneinchsidehop is offline   Reply With Quote
Old 12-18-2009, 05:57 AM   #4
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
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
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-21-2009, 08:59 AM   #5
Registered Member
 
rgathright's Avatar
 
Join Date: Apr 2008
Posts: 189
Country: United States
The answer to all questions is:
42
rgathright is offline   Reply With Quote
Old 12-21-2009, 09:13 AM   #6
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 12-23-2009, 03:54 AM   #7
Registered Member
 
oneinchsidehop's Avatar
 
Join Date: Aug 2007
Posts: 165
Country: United States
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.
__________________
Mike
_______________________________________________

"If you want to save gas I suggest you permanently remove the drivers seat and steering wheel. That seems to help." -Oscar Halverson

oneinchsidehop is offline   Reply With Quote
Old 12-23-2009, 07:28 PM   #8
Registered Member
 
GasSavers_JoeBob's Avatar
 
Join Date: Oct 2007
Posts: 698
Country: United States
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?
__________________

__________________
"We are forces of chaos and anarchy. Everything they say we are we are, and we are very proud of ourselves!" -- Jefferson Airplane

Dick Naugle says: 1. Prepare food fresh. 2. Serve customers fast. 3. Keep place clean.



GasSavers_JoeBob is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Fuelly Android Apps
No Threads to Display.
Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 09:26 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.