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[Luke]

Sorry for my previous, unclear, message. I was in a hurry. We are building a beverage cooler that will circulate ice water around a number of aluminum cans. While there is always conduction when one object comes in contact with another of different temperature, we are focusing on the aspect of convection. Convection occurs when a fluid of some type has mass flow in one direction thereby carrying the heat off the surface as it flows by. Thus, by circulating the water in the container we will have an increased cooling rate as compared with standing water. For calculating purposes, I need a ball park estimate of the normal convection (unaided by any circulating device) and of the forced convection rate (aided by a circulator) for aluminum cans in water.



TIA,
Luke

[djack77494]

Luke,
Keep in mind that you will have convective heat transfer whether you pump the ice water or not. If you pump ice water past your aluminum cans, you will have forced convection; if the cans just sit in "staqgnant" ice water, you will have free convection. That is because heat will leave the beverage container and warm up the icy water everywhere along the wall. The warmed water will rise and be replaced by cooler water. This heat transfer is far in excess of what you could get with probably the best of straight conduction transfer.

Enough said. For details, refer to your favorite heat transfer textbook.
Doug