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Convection question

  1. Nov 18, 2007 #1
    Hi, I was wondering if someone could help explain how the following shapes would affect convection. What it is is a heat plate with nothing, a bundle of tubes, and just fins. It's in a vertical tube and the air flows upwards. I understand convection but I don't get how it would be affected in terms of a physical object such as these in its path.

    http://img231.imageshack.us/img231/718/heatplatesf1.jpg [Broken]
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Nov 22, 2007 #2


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    The rule of thumb I use is that flow lines just downstream of an obstacle get very close to their far-away away structure within a distance comparable to the width of the obstacle. So if the tubes have a diameter d, then at a distance d downstream from each tube, the flow-lines are essentially homogenized again. For some shapes (tear-drop, for instance), this distance can be much smaller than the width of the object.
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