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Forced evaporative cooling in high humidity conditions

  1. Feb 3, 2010 #1
    hello all,

    We live in a hot part of the world with the extra bonus of high humidity - around 90%. We don't have A/C, and don't really want to get it (energy use).

    Evaporative cooling wont do much (towel on head) becuase of water saturation in air. Would a cold wet towel + fan force water to evaporate from a hot body (taking heat with it)?

    thanks
     
  2. jcsd
  3. Feb 3, 2010 #2

    russ_watters

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    Staff: Mentor

    Well if the towel starts off cold, you'll transfer more heat initially while you warm it up. And a fan always helps.
     
  4. Feb 4, 2010 #3
    thanks Russ - I've seen you contribute to loads of peoples threads.

    I like to have confirmed some general comments to which yes or no could be added by someone in the know......(Russ..... :-p):

    1. If the water on the towel is cooler than the body temperature, heat will transfer from the body to the towel. As the towel heats up, the transfer rate will slow down. Once the towel reaches the same temperature (or close) of the body, the transfer of heat will stop.

    2. Would cool water on the surface of the skin, have the same effect. I'e, transfer heat from the body to the water (heating it up)?

    3. If cool water does work, and it gets warmed up by the body, in high humidity the water would stay on the skin....and would only evaporate off the skin if done by a fan....(forced off).

    4. If forcing water off the skin in high humidity works with a fan, blowing water off the skin - where does the blown off water go if the air is already at 90% humidity? - does it blow off on to the nearest adjacent surface... or go where ever the fan blows it?

    thanks.... :-)
     
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