1. The problem statement, all variables and given/known data I am trying to find out the rate at which I need to pump water into a device generating a specific amount of heat to keep it at a low temperature. I have not taken thermodynamics yet, and so I am trying to use a very basic model. The water is pumped through a copper pipe. I know the following: - Temperature of incoming water - length and diameter (both inner and outer) of the copper pipe - The total heat being generated by the device I am looking for an equation that will have these as independent variables and give me the needed flow rate of the water. Again I am looking for a ballpark answer, so if there are some other assumptions I have to make, like uniform heating, I can get away with it. 2. Relevant equations unkown 3. The attempt at a solution I have tried looking around the internet but am not familular enough with the material to know what I am looking for. Any help would be greatly appreciated, even if it's just pointing me in the right direction.