Calculating Pump Head: Equation & Parameters Explained

[ajoyce]

Hi there

Looking for some help with calculating the head for a pump

The example in my textbook isn't exactly clear.

Is there a specific equation I can be using or can it be worked out having the following:

volumetric flow rate
density of fluid
gravity
pump efficiency
pipe diameter
equiv length head loss

 

[SteamKing]

IDK about calculating pump head. The head and flow rate of a pump are generally derived from testing the pump. This data is then incorporated into a characteristic curve for the pump.

https://app.qleapahead.com/rtp/LibraryGet.aspx?asset=85798,63

 

[ajoyce]

Thanks I will have a look and see what you have provided

 

[Travis_King]

If it's discharging into atmospheric pressure, e.g. the top of a tank, then the head of the pump will be equal to the head loss due to pipe friction plus the head loss due to elevation change between the suction water level and the discharge level.

 

[bigaggie]

IDK about calculating pump head. The head and flow rate of a pump are generally derived from testing the pump. This data is then incorporated into a characteristic curve for the pump.

It can be done, but it's not very straightforward. There are several "modeling" equations that can be used to predict performance based on the geometry of the impeller (or plungers if a piston pump), but you are correct, the only real way to know how a pump will perform is to test it.

That said, I really don't understand the original question. It sounds like a summation of the losses will give you the answer they're looking for, but I could be misunderstanding the statement of the problem.