# Sizing Fuel Pump

Discussion in 'Off-Topic' started by thakid87, Jul 21, 2011.

1. ### thakid87 Thread Starter Active Member

May 23, 2009
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0
Hello.

I didn't know where to post this and I am hoping I can get some kind of feedback to point me in the right direction here.

The horizontal run from the fuel tank is 10 m and the vertical run is 6 m.

How can I determine what hp pump I will need? The generator has a fuel flow rate of 120-150 lph depending on load.

Any help I can help would be greatly appreciated.

2. ### GetDeviceInfo AAC Fanatic!

Jun 7, 2009
1,611
238
Luckily for you, fuel pumps are typically rated in gal/litres/min/hr. search for such

3. ### thakid87 Thread Starter Active Member

May 23, 2009
122
0
I've got that part down pat, but my issue is with the run/rise that it has to push that fuel. The several pump manufacturers that I've spoken to have salespeople that really don't know if their pumps are capable of this. So I was hoping to see if someone can help me calculate this.

Thanks.

4. ### GetDeviceInfo AAC Fanatic!

Jun 7, 2009
1,611
238
even though hp is a component, the pump won't be rated as such. Your run will create a pressure drop dependant on it's size and head. Your pump's performance curves will indicate it's volume at the pressure you require to overcome the drop plus your requirement at the delivery point. Call a real pump salesman up and they'll spec the system for you.

Jul 7, 2009
1,585
142
You're talking about a fluid flow problem. These kinds of practical problems are usually solved using Bernoulli's equation with additional terms for the effects of the pump and friction losses in the piping and fittings (including the rather famous D'Arcy-Weisbach equation). You typically need to know the fluid pressures, pipe size(s), pump characteristics, and different fittings. I'm surprised the pump people don't have simplified tables to help you look up the information you need. At the very least, you should submit your setup to them and ask them to submit it to their engineering staff for a recommendation. That's one of the things they get paid for.

6. ### strantor AAC Fanatic!

Oct 3, 2010
4,988
2,993
There's a lot of factors.
length of pipe
smoothness of pipe
# of bends
you've indicated 6m rise, so that's a start, you need a pump capable of at least 10 ft of head
diameter of pipe
rate of flow

lots of math: http://ohioline.osu.edu/b912/step_8.html

I suppose you could just shotgun this issue and get a pump with double the flow rate spec and double the head pressure spec.

or do the due diligence of all this math, or as mentioned call a sales rep