Tank Heat Losses

[adpit]

Dear All,

I am evaluating heat losses from tanks.

I am assuming zero heat losses from bottom of the tank and for the side wall I am using 3E PLUS software.

Now I have an issue with the roof of the tank. I found that for uninsulated sections there is a correction factor for the heat losses based on type of liquid product.

I get the heat losses from uninsulated tank flat top from 3E plus and I am assuming a 0.65 factor for Fuel Oil type but i think i cannot use this value for all the types of roof. Roof can be of several type, floating, no floating, dome or flat and so on.

could any of you give me some tips on which correction factor i need to use?

Many thanks,

 

[ChocLab]

I have done many calculations in the past wrt heat losses from a tank. To ignore the heat loss due to the ground is not exactly a good assumption. Remember that for a tank, the section of the tank that sits on the ground is conduction heat transfer, whereas the rest of the tank is mainly convection heat losses.

The only time I would consider ignoring the ground is if the the area of the tank on the ground is very small as compared to the rest of the tank (if there is such a design) or something like a propane sphere which is supported off the ground on sleepers.

To consider the ground losses, you need to know what materials are under the tank as far as the frost layer. Find out the depth to the frost layer and the temperature of it from the plant design specifications.

I hope this helps.

KL