Source for Heat Transfer Coeficients

[SandCounter]

When I was in school, my number one question to the professor was always, "Great, I understand the physics, but in the real world, where do these givens come from?" The answer was always, "The company you work for will have the charts and tables of empirical they prefer you to use." Even many text books that provide sample tables have this kind of disclaimer.

Here I am, 12 years out of school, and after working at three different companies, I've found that this is almost never the case.

Currently I am working on a heat balance between tanks which contain combinations of water, fuel, and air. The tank walls are steel and coated. The application is fairly low risk and I am only trying to "ball park it," within, say, about 20%. For preliminary calculations, I am using overall heat transfer coefficients from various plate exchanger manufacturers which seems to match some other online sources for general air-steel-water coefficients. The coatings, of course, are a big unknown and the coating manufacturer does not seem to produce this data.

Can anyone recommend a reference for various overall heat transfer coefficients?

Thanks in advance for any assistance.

 

[IRstuff]

Seems to me that you are barking up the wrong tree. While thermal conductivities are certainly deterministic, overall htc's are no, since they depend on operating/ambient conditions, area, thicknesses, etc. Why would there be a single number for something that has a fairly large design range? If you really understood the physics of heat transfer, then you should be capable of setting up the equations and solving them.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[SandCounter]

Thanks for the helpful post IRstuff.

 

[Latexman]

Sorry, the best reference I have for various overall heat transfer coefficients is Business Confidential. The second best that I know is Perry's Chemical Engineers' Handbook. There must be others.

Good luck,
Latexman

To a ChE, the glass is always full - 1/2 air and 1/2 water.

 

[asifraza0]

Try Branan's chemical engineers handbook; it has numerous H-T coefficients and also try Heat Transfer Donald Kern
Good Luck
Araza

Asif Raza

 

[EdStainless]

The issue with heat transfer is that most of the resistance is in the boundary layers. I most applications that I have worked with I see 60-75% of the total resistance in the boundary layers, less than 5% in the tube wall, and other 20-30% in the fluids. And since the boundary layer conditions are so dependent on the specifics of the application .... a good grasp of the fundamentals of estimating them is about all that you can hope for.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[SandCounter]

EdStainless, thanks for the input. This will help me use my time more efficiently by securing boundary condition data.