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Heating compressed air to provide lift

  1. Jan 2, 2009 #1
    Just a question about heating compressed air..

    I know generally how hot air works.. You heat it and particles expand and creates lift.

    So my question is, Does heating compressed air provide any lift? if so how much in relation to normal air?
    if I had 100m^3 of air heated to 120C,
    would it provide the same lift as the (same amount) but now compressed air heated to 120C

    Does this make sense? or have I missed the point...
  2. jcsd
  3. Jan 2, 2009 #2

    Vanadium 50

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    No, it won't provide any lift at all. Compressed air is heavier than uncompressed air.
  4. Jan 2, 2009 #3

    Andrew Mason

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    In order to rise, the density of the air has to be less than the density of the surrounding atmosphere. Heating compressed air could provide lift if it was heated and allowed to expand so that its density was less than the surrounding atmosphere. But then it would not be compressed air. as Vanadium has pointed out.

  5. Jan 2, 2009 #4
    Ah I see, I misunderstood the concept of compressed air, thanks for your replies.
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