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Heat transfer along a pipe - excel calcs?


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#1 Supe

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Posted 01 August 2011 - 01:42 PM

This one is well out of my realm of expertise, considering it's been far too long since I've even thought about that blur known as thermodynamics.

What I'm looking for is an excel file or any guidance to help me calculate the approximate temperature drop along a given length length of pipe. We often wrap pipe spools for heat treatment, and frequently have sensitive equipment/valves in proximity to the heater pads/insulation. I'm looking for something that will allow me to ballpark "in still air with no air/fluid flow through the pipe ID, a pipe of X thickness will see a temperature drop of approximately Y degrees over Z inches from the heat source."

Any help would be greatly appreciated.

#2 Master slacker

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Posted 16 September 2011 - 11:35 AM

Dude. No love.

BTW, I can't help you with this.

#3 pbrme

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Posted 20 December 2011 - 01:15 AM

Supe, did you ever find info? I just now read. You should know this stuff like the back of your nutsax.

#4 Supe

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Posted 20 December 2011 - 09:20 PM

I did not.

As far as knowing it... pfft. Been a long time since I've dealt with anything not specific to metallurgy or welding codes.

#5 pbrme

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Posted 03 January 2012 - 06:01 PM

I can attempt to provide some insight into this, but need some additional information on this setup. A sketch would be good. Pipe & Insulation; size, length, wall thickness, material... etc. Location of heat source, and instrumentation, and also heat source min. max. would all be variables to adjust in the test boundary.

"We often wrap pipe spools for heat treatment..." what is the wrap?
"in still air with no air/fluid flow through the pipe ID..." You're still going to have natural convection.

I think I can help with setting up a spreadsheet for playing with the variables, but a generic sketch of a setup would be nice.

#6 Supe

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Posted 03 January 2012 - 06:28 PM

pbrme: They are wrapped with ceramic heaters as the heat source. Understood on the natural convection comment, but we're also only looking to ballpark these values. Pipe is capped off at both ends. If you PM me an e-mail address, I can send you a rough sketch.




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