Heat tranfer coefficients of steel??? 4

[carbide]

Any one know the heat transfer coefficient of any type (idealy Cr25, Ni20 steel) of stainless steel in (W/m^2K) PLEEEEASE?
Thanks,

ALEK
Desperate final yr avionics student

 

[svanels]

What are you looking for?
The standard properties like
Specific Heat c[sub]p[/sub] {kJ / (kg * K)}
Thermal Conductivity k {W / (m * K)}
can be found in tables.
The heat transfer coeficient depends on the situation, you have to describe your problem.
Check out thread391-4727

Regards


Steven van Els
SAvanEls@cq-link.sr

 

[tstead]

I just wanted to expand a little bit on svanels's answer - which is correct, but not as descriptive as you may need. The heat transfer coefficient, U, varies with the mode of heat transfer used - it is not a material property, per se.

For example, if you had a steel plate sitting in still water, you would expect a much different heat transfer coefficient than if the water were in motion.

The heat transfer coefficient is also dependant on geometry and position. For example, you could expect vastly differnt heat transfer coefficients with a horizontal tube heat exchanger as opposed to a verticle tube heat exchanger. In addition, you could expect even more of a change if you had a plate heat exchanger - even if you make the heat exchanger out of the same material and have the same fluid being heated/cooled.

In very few instances will you ever know what the heat transfer coefficient is by virtue of the materials used. You must calculate it from the geometry involved, the mode of heat transfer, and the fluids involved. This sort of calculation cannot be readily described in this forum except for a couple of simple cases. If you want, you can describe your situation in detail and someone might be able to assist you better.

Tim

 

[DonLeffingwellPE]

The above posters are exactly right. However, if you know the fluid involved, and the geometry, there are some published charts for ranges of heat transfer coefficients.
Some books that have these charts:

Mark's Handbook, Handbook of Heat Transfer, etc.

These type of charts are useful for estimating purposes, feasiblity studies, etc

Don Leffingwell