Table top fountain pump

[mohtogh]

Hello,
I want to make small pump for my table top fountain. Typical spec. are Q= 100 gph and H= 3 ft .
I have three question about it :
1. what is the shape for impeller?
2.What is the method for sealing? (Instead of mechanical seal )
3. It must be sealed , because works under the water .
What is the method for sealing ?
Thanks

 

[insideman]

You want a pump to fountain 100 gph 3 feet high. I converted gph to cubic feet per minute to get units I am used to working with. 100 ghp = 0.2228 cfm. I also assumed H = 4, not 3, to allow for some losses in the fountain.

Then I calculated Ns= N(cfm^.5)/H^.75 = .1669N.

We would like Ns to be between 500 and 800 for best efficiency. Try 500 = .1669N, then N is 2996 rpm. Say 3000 rpm. This rpm should be available in small induction or shaded pole motors.

Detail design of the pump and motor selection is a bit beyond the time and effort I am willing to spend on a freebie project... Let me know if you want to go farther.

For sealing, consider a magnetic coupling. Zero leakage!

Does this help?

 

[pardal]

I want to keep track of this post.
You can reach me at k281969@hotmail.com
but keep your post here for mutual benefits.
Pardal