Pump Head Calculation (When to include the velocity head?) - NEWBIE
Pump Head Calculation (When to include the velocity head?) - NEWBIE
(OP)
In what conditions do I need to include the velocity head in determining the total head of the Pump i'm sizing?





RE: Pump Head Calculation (When to include the velocity head?) - NEWBIE
However, if you are dealing with a high flow, low head installation then perhaps the velocity head is important. Most pipe sizing software will automatically calculate the velocity head for you, or if you are building a spreadsheet then just add in one more formula and you can be sure whether the velocity head is important or not every time.
Katmar Software - AioFlo Pipe Hydraulics
http://katmarsoftware.com
"An undefined problem has an infinite number of solutions"
RE: Pump Head Calculation (When to include the velocity head?) - NEWBIE
The example they give has a velocity of 8.5m/sec where it makes ~5% difference, but again on a relatively low head output.
In general I would say that if your output pressure is more than 5 bar and velocity where you're measuring the pressure less than 4-5 m/sec, you can safely ignore it. - Katmars example is less than 0.3% of the head.
So just do it as a quick side calc (not exactly hard) and see if its > 1-2% of the pump head. If it is then add it in, if not just forget about it.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Pump Head Calculation (When to include the velocity head?) - NEWBIE
For most pumping applications, the velocity is a small component of the pump head. However, for some pump applications with very high flows and low discharge heads, the velocity head may become important. See the example.
http://www.pumpsandsystems.com/pumps/september-201...
http://www.pumpsandsystems.com/topics/pumps/centri...
RE: Pump Head Calculation (When to include the velocity head?) - NEWBIE
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist