Previous in Forum: Welder Trade Test   Next in Forum: GRP Pipeline Design
Close
Close
Close
10 comments
Rate Comments: Nested
Associate

Join Date: Jul 2008
Posts: 28

Volumetric Flow for Centrifugal Pump

08/18/2008 8:15 AM

Knowing a centrifugal pump's speed (RPM), impellers diameter and exit holes, how can I determine its approximate volumetric flow.

Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Power-User

Join Date: Aug 2007
Posts: 479
Good Answers: 9
#1

Re: Centrifugal pump's volumetric flow.

08/18/2008 8:46 AM

You can't. You need to know something about the discharge head. The volume depends widely on it.

Register to Reply Score 1 for Good Answer
Guru
United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on.
Posts: 32175
Good Answers: 839
#4
In reply to #1

Re: Centrifugal pump's volumetric flow.

08/18/2008 9:42 AM

Quite. The pump operates where the pump characteristic curve and the system characteristic curve intersect.

__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
Register to Reply Score 1 for Good Answer
Associate

Join Date: Jul 2008
Posts: 28
#5
In reply to #1

Re: Centrifugal pump's volumetric flow.

08/18/2008 10:02 AM

The only information I have is that the medium is compressed in the chamber ( between rotor and stator) with pressure up to 10 bar.

Register to Reply
Guru
Popular Science - Biology - New Member Hobbies - Musician - New Member APIX Pilot Plant Design Project - Member - New Member Hobbies - CNC - New Member Fans of Old Computers - ZX-81 - New Member

Join Date: Jan 2007
Location: Centurion, South Africa
Posts: 3921
Good Answers: 97
#2

Re: Centrifugal pump's volumetric flow.

08/18/2008 9:25 AM

Try and enter the name and model number of the pump into google. If you are lucky you may get a selection table or even a pump curve.

With this info you will have a rough indication of the capacity.

__________________
Never do today what you can put of until tomorrow - Student motto
Register to Reply
Power-User

Join Date: Aug 2007
Posts: 479
Good Answers: 9
#3
In reply to #2

Re: Centrifugal pump's volumetric flow.

08/18/2008 9:28 AM

Yes. The pump curve would be nice to have. But if you get it, then you will need TDH. Sort of a Catch 22!

Register to Reply
Guru
Popular Science - Biology - New Member Hobbies - Musician - New Member APIX Pilot Plant Design Project - Member - New Member Hobbies - CNC - New Member Fans of Old Computers - ZX-81 - New Member

Join Date: Jan 2007
Location: Centurion, South Africa
Posts: 3921
Good Answers: 97
#6
In reply to #3

Re: Centrifugal pump's volumetric flow.

08/18/2008 10:39 AM

True but it is at least something to work with.

He has the rpm, impeller diam, and the head of 10 bar. That may be enough to get a good indication.

__________________
Never do today what you can put of until tomorrow - Student motto
Register to Reply
Guru
Popular Science - Biology - New Member Hobbies - Musician - New Member APIX Pilot Plant Design Project - Member - New Member Hobbies - CNC - New Member Fans of Old Computers - ZX-81 - New Member

Join Date: Jan 2007
Location: Centurion, South Africa
Posts: 3921
Good Answers: 97
#7

Re: Centrifugal pump's volumetric flow.

08/18/2008 10:49 AM

Hi gerdsmit

A bit more info will be helpful.

Where are you from?

Do you have a make and model no?

If not what about a photo? or what is the colour?

Is the pump on its own or in a system?

What do you intend to do with the pump?

Will the pump make a good doorstop?

__________________
Never do today what you can put of until tomorrow - Student motto
Register to Reply
Associate

Join Date: Jul 2008
Posts: 28
#8
In reply to #7

Re: Centrifugal pump's volumetric flow.

08/18/2008 11:15 AM

Hi Hendrick,

I'm from Fla. USA. It is still a design of a reactor that pretends to work like a centrifugal pump. Centrifugal force will force he fluid to move through small holes in an outer stator. Tangential velocity will be around 40/50 m/s. According to Bernouilli's law the fluid will eprience a pressure drop due to increase of speed. To manage the pressure drop I need an approximation of the flow.

Register to Reply
Power-User

Join Date: Aug 2007
Posts: 479
Good Answers: 9
#9
In reply to #8

Re: Centrifugal pump's volumetric flow.

08/18/2008 11:25 AM

This is called modelling. You want to simulate results of something using something else.

So the problem remains. The "simulator" or "model" or "analog" cannot predict results without having the basic parameters for the device that you are attempting to "model".

One solution is to create model "sets" for specific solution "range of values". Work out the characteristics for each "set". Then pick the set that is most appropriate for the actual device for further study or prototyping.

Sort of a trial and error approach.

Register to Reply
Guru
Popular Science - Biology - New Member Hobbies - Musician - New Member APIX Pilot Plant Design Project - Member - New Member Hobbies - CNC - New Member Fans of Old Computers - ZX-81 - New Member

Join Date: Jan 2007
Location: Centurion, South Africa
Posts: 3921
Good Answers: 97
#10
In reply to #8

Re: Centrifugal pump's volumetric flow.

08/18/2008 3:09 PM

Hi gerdsmit

I won't be of much further help.

Just out of curiosity

Are you doing a scale model? and do you have to apply scaling rules for flow and time similar to hydraulic models for dams?

__________________
Never do today what you can put of until tomorrow - Student motto
Register to Reply
Register to Reply 10 comments

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Copy to Clipboard

Users who posted comments:

gerdsmit (2); Hendrik (4); PWSlack (1); user-deleted-9 (3)

Previous in Forum: Welder Trade Test   Next in Forum: GRP Pipeline Design
You might be interested in: Centrifugal Pumps, Volumetric Gas Flow Switches

Advertisement