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Drag coefficient for plate perpendicular to airflow

  1. Mar 26, 2012 #1
    from wikipedia, it is written 1.98-2.05 for flat plate perpendicular to flow(2D) , but I have a differrent b/h ratio plate, where h=157mm and b=816mm , b/h=5.197

    how to get the drag coefficient in this case?

  2. jcsd
  3. Apr 9, 2012 #2
    What are your flow conditions?

    Laminar? Turbulent?

    Are we just talking about ambient air? or God blowing on the plate... =)

    Give me the Reynolds number and I can help you out.

    Cheers =)
  4. Apr 9, 2012 #3
    For a plate perpendicular to the flow the reynolds number will not matter much. That wikipedia page gave a Cd for a 3d flat plate and you will probably be ok using that. Otherwise there is not an easy way to figure this out, your best bet would be to find some reference with similar measurements
  5. Apr 9, 2012 #4


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    Given that this is going to be entirely pressure drag, the state of the flow (laminar vs. turbulent) won't matter a bit. The only thing that could potentially play a role in would be the nature of the vortices that would be shed behind the plate, but the aft side is going to be massively separated and emitting vortex streets regardless.
  6. Apr 10, 2012 #5

    Did not properly read OPs question. I thought he was talking about parallel flow on plate.

    Whoops =)
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