Optimum Tank Size

Welcome aboard, scotty. Hope you enjoy your time in the forum.

You ask about a pump. Many pumps take suction from a tank of size zero - there is no associated tank, just a source of working fluid.

In order to generate a bit more meaningful discussion you probably want to provide more information about the installation, the situation, the goals of your effort.

Also, you might note there is sometimes a significant difference between minimum and optimum (as in the title.)

Best Regards.

Hello Scotty. Welcome.

The tank size has nothing to do with the pump minimum-maximum or optimum.

You design your tank size as per the volume you require to store with a 10%-15% margin so it is not undersized and overflows.

If it is undersized then you have to find a bigger capacity pump to pump faster.

If it is oversized then you've already unnecessarily wasted your money.

The in-between is your "optimum" size.

Do you intend the suction tank to enable prime retention in the case of air intakes or self priming?

Hello scottybritish

Not clear from your question, but perhaps you're asking about minimum tank size to give acceptable pump start frequency? Volume required between start and stop (not total tank volume) given by V = Q/(4*N) where Q = pump flow, m³/h and N = maximum allowed starts per hour. This is typically 5 - 6, but some can take 20 per hour. Max starts/h occurs when the flow into the tank = 1/2 the pump flow, as you can show by a quick bit of calculus if you're into that.

Doesn't just apply to suction tank, if you're filling a tank from a large reservoir it would be the discharge tank. Also if there are 2 or more pumps on staggered start/stop, only the flow per pump needs to be used in above,

Cheers....Codey

You must also maintain the NPS (net positive suction) so this would refer to the hight of the tanks assuming this tank is open to atmosphere. I am envisioning a tower water sump for a cooling tower.