Convection and radiation from a rotating drum? 1

[TrevorH]

Can anybody help?
I am trying to find the heat loss from a rotating drum. The following condition would apply - Solid steel drum dia 1m x 0.5m long rotatingi air at 1000rpm. Temperature 100 degC with ambient of 20 degC.
I am finding great difficulty in bringing my distant degree knowledge up to date by using various library text books.
Has anybody a good reference book I should use or has some direct knowledge information?
It would be much appreciated. Trevor

 

[theonlydave]

Hi, do you have cross flow or is the heat transfer in still air? You may like to check out the following references that you may find useful if the rotating drum is in still air:

T.Anderson and O.A. Saunders, Proc. Roy. Soc. A 217, 555, 1953

W.M. Kays and I.S. Bjorklund, Trans. ASME 80, 70, 1958

Theodore Theodorsen and Arthur Regier, “Experiments on Drag of Revolving Disks, Cylinders, and Streamline Rods at High Speed,” NACA technical Report 793, 1944

Baris Ozerdem, “Measurement of Convective Heat Transfer Coefficient for a Horizontal Cylinder Rotating in Quiescent Air,” Int. Comm. Heat Mass Transfer, 27, 3, 2000

John H. Lienhard IV and John H. Lienhard V, “A Heat Transfer Textbook,” Phlogiston Press, Cambridge, Massachusetts, 2005

John R. Howell, “A Catalog of Radiation Heat Transfer Configuration Factors”,

http://www.me.utexas.edu/~howell/intro.html,

University of Texas at Austin

Michael C.Wendl, “Fundamentals of Heat Transfer Theory and Applications”, Department of Mechanical Engineering and School of Medicine, Washington University, 2003

 

[TrevorH]

Hi theonlydave
Thanks for your reply. The rotating drum is in still air except for the fact the action of the rotation will produce forced convection!
I will try to obtain copies of your suggested references. How do you specify the length factor to calculate the Reynolds and Nusselt numbers - Drum circumference? and using this how would the average heat transfer coefficient be established? Hope you can help - thanks

 

[prex]

Interesting problem.
I don't think that the drum peripheral speed matters very much, as in fact this doesn't cause turbulence in the air (unless you have some kind of fan blades on drum surface).
Therefore I would treat this problem as a natural convection problem on a still surface, though this could somewhat underestimate the exchange.
A typical value for the heat transfer in your conditions (including radiation) is 10 W/m²°K, the double when air is forced to move, like in wind: I don't think that by analysis you will get better approximations.

prex

http://www.xcalcs.com

Online tools for structural design

 

[theonlydave]

The Rotational reynold number is pwD^2/(2u). p is the density of air, w is rotation speed, D is diameter, u is dynamic viscosity of air. The reference i mentioned should be sufficient for your problem, please check those out.