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Old 11-22-09, 07:39 PM   #26
AC_Hacker
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Quote:
Originally Posted by dremd View Post
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The In Floor PDF you linked to was SUPER informative!

One thing I'm still trying to figure out is pump sizing. I see the head through x feet of y pipe, but what I don't understand is what is a good flow rate.
dremd,

I'm assuming that you're referring to this link?

http://www.radiantcompany.com/manual...l_web-2009.pdf

I'm still trying to work out the pump thing myself...

I know that it's in my hydronic book, but I haven't dug that deep yet.

So far, I know that if you pump fluid through a pipe, that there is a pumping rate where 'turbulent flow' begins. An it is desirable to pump fast enough to reach turbulent flow, because heat transfer is enhanced, and hard as it is to believe, power required is reduced.

The factors affecting the threshold of turbulent flow are:
  • smoothness of pipe
  • diameterr of pipe
  • viscosity of fluid
  • etc.


If you're gonna do some research, there is a mathematical construct called Reynolds number that is pivotal in calculating pump size.

There's probably a free program that will do this for you, or a Java Script page calculator that will do the trick.

Please share with us what you learn.


Best Regards,

-AC_Hacker

Last edited by AC_Hacker; 11-22-09 at 07:42 PM..
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