Quote:
Originally Posted by Phantom
It probably will not make much of a difference since it is plastic but use some coarse sandpaper on the barrels to increase the surface area to help conduct the heat.
Using a radiator would work you could completely fill the tanks and have a pump move water from the center tanks to end end one with the radiator moving the water to the remaining tank.
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Thanks.
I think (maybe) there is a tendency to overestimate the negative effect of using a plastic wall barrel. The conductivity of the polyethylene is 0.26 BTU/ft-hr-F. If you assume a 0.1 inch thick barrel wall, this works out to an R value of 0.03 for the barrel wall. The R value of a moving air film (5 mph?) is R 0.17. So, it seems like the thermal resistance of the air film is much greater than the thermal resistance of the barrel wall. There is also the resistance of water film next to the barrel wall on the inside. I'm inclined to think that even though a metal barrel wall would be much more conductive, it would not make much difference because of the resistance of the air and water films inside and outside the wall?
I understand that when Steve Baer change from metal barrels to plastic barrels on his living room barrel wall that he did not see any difference in performance.
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Got the 2nd fan yesterday from Grainger, but the weather is still much to cool to try a new setup.
Gary