Thanks for all your replies. You guys are right, my U value is way too high. And, Montemayor raise a good point that if we keep the air flow arround the tank to minimum that it is reasonable to assume a thicker air film thickness e.g. 1mm, Now, use the thermal conductivity of 0.025 W/mC, I get...
It is a non-insulated steel tank, assuming no scale form in the initial heating. If I only use thermal conductivity of air 0.025 W/mC, and air thickness 0.2 mm. I got a high U value of 125 W/m2C. The tank heat transfer surface area is about 20 m2, which are all 4 walls of the tank 14'x40"x6'...
I know this probably a chem eng 101 question for you guys, but I need to help so that I can get a right heat exchanger for our processing tanks.
I am currently working on aluminum anodizing line setup. When I calculate the heat loss for the processing tanks I got results, which reaaly puzzled...
