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Unread 04-19-2004, 10:07 AM   #8
rkb2
Cooling Neophyte
 
Join Date: Apr 2004
Location: Europe/Slovenia
Posts: 6
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To Cathar

1. What do you mean by h ?
2. If the cup is long enough (i'd say if cup heigth > diameter) than the cascade is just heat transfer in a tube (i will give you an example of the velocitiy of water flowing trough a jet in a cup later), except of course for the base of the cup, for which I just assumed that the film coefficient is the same as in the tube (I could be way wrong here).

To WAJ_UK

1. The film coefficient (type this in GOOGLE) is about the same as the heat transfer coefficient (W/m*K)only this time in the join between two different mediums (copper/water, copper/air) and is measured in W/m^2*K.

lets say for heat transfering in the same medium (= heat conduction)
Q=heat transfer coefficient *medium length*temperature difference

lets say for heat transfering between copper/air (= heat convection, forced convection)
Q=film coefficient *area*temperature difference
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