Chemical Forums
Specialty Chemistry Forums => Chemical Engineering Forum => Topic started by: DanielGeltman on March 09, 2017, 04:41:01 AM
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Hey everyone,
I have a problem figuring out the shape factor in the following problem:
(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fi65.tinypic.com%2F29xiv87.jpg&hash=754241ff2d4a4d96acae9dabf0225e6028af5e56)
"Surfaces 1, 2 and 3 are very long (I assumed infinite..)- surfaces 1 and 2 are identical plates and surface 3 is a quarter of a cylinder. There is vacuum between the surfaces.
What is the value of the shape factor F33? (That's not the real question but that's where I had a mistake)"
So.. I decided to use the following figures:
(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fi63.tinypic.com%2F53pqa8.jpg&hash=bebd5bd0c4174a76d1c9bf3d2a558786866f0b8f)
If we assume that there is an inner cylinder of infinitesimal radius we'll find out that the shape factor F33 is 1, but since we have only quarter of a cylinder I assumed that the shape factor F33 would be 0.25.
I was wrong but don't know why. I also don't know the real shape factor-just that it's not 0.25.
Could you please help me?