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Radiation! How radiation affects different configurations of a clothes horse

  1. Jan 20, 2012 #1
    I have a clothes horse on which clothes can be hung parallel to each other roughly 50 cm apart. I place the clothes horse perpendicular to the radiator so the heat from the radiates along the length of the wet clothes. However my flatmate places the clothes horse parallel to the radiator so the heat must first radiate through one wet garment before getting through to the second garment.

    Can anybody help me with a scientific solution to this question. Any equations for working this out would be good but I'm mainly looking for a description as to which drying configuration would dry the clothes the fastest.
  2. jcsd
  3. Jan 20, 2012 #2
    Hang one article of clothing right side up, and another upside down. Then place one inside the other. Keep in mind, I have no idea what a clothes horse is... but the general idea is to make two articles of clothing dry as though they were more or less one. Drying the Front side of one shirt and the back side of the other in roughly equal time.
  4. Jan 20, 2012 #3


    User Avatar
    Gold Member

    Clothes horse - much better name than a clothes drying rack - I like.

    I imagine you are talking about a baseboard heater or radiator, which actually in operation heat a room by convection and very little by means of radiation.

    What happens is as follows:
    - the air in your room has a certain humidity level, which means the amount of moisture in the air
    - 100% relative humidity means that the air is completely saturated with moisture and can hold no more. If your room is 40% relative humidity, clothing will still dry.
    - and as the air warmed by the radiator is able to hold more moisture - the relative humidity of the warmed air has fallen to a lower level.
    - the warmer air, now a little "dryer" can accept moisture from your clothes a little more quickly
    - the warmer air rises, accepts moisture, becomes a little more humid, and is continiously replaced by more "dryer" warm air that passes around the clothing.

    So the question of whether the orientation of parrallel or perpindicular placement of the clothes horse to the radiator will dry clothes the fastest, is subject to the air circulation pattern set up around the clothes. If one is drying one or two pieces of clothing, then parrallel would be the best as both pieces of clothing are above the radiator. As the number of pieces of clothing increases, more garments ( or parts of the garment ) will be farther from the radiator and not dry as quickly, so I suspect placement, parrallel or perpendicular, would not matter, all things being equal,

    On the other hand, the small amount of radiation transmiitted from the radiator to the clothing, would be blocked by parallel placement of the first piece of clothing.

    You could test orientation and clothing drying times by timing "test runs" of each orientation and note the length of time it took to when you feel the clothing is dry.
  5. Jan 21, 2012 #4


    Staff: Mentor

    If you are using radiant heat then think of the radiator as a big light bulb. Then position the clothes so that as much of the "light" from the light bulb is blocked, as though you were trying to dim the room.
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