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Pump characteristic curves

Pump characteristic curves

Pump characteristic curves

(OP)

Question: Has anybody ever seen centrifugal pump characteristic curve plots (on cartesian coordinates) with head on the ordinate vs. the square of the flow rate on the abscissa to show a "straight" contour ?

Could you comment on the advantage of such, especially when referring to large pumps with different speeds of rotation ?

How would these coordinates affect HP, NPSH and efficiency plots ?

RE: Pump characteristic curves

I have not seen one, but I have made reversed coordinate curves (not square root of Q) myself on occasion for hydraulic analysis.  I makes it easy to get the equation for Q vs dH, which helps when solving Kirchoff loop equations and finding the output signal needed from a pump's flow/speed controller based on pressure transmitter's input.

http://virtualpipeline.spaces.msn.com

RE: Pump characteristic curves

25362,
It very unusual.
Performance curves, Q-H and TDH system curves has predominant cuadratic behavior.
Also NPSHr and NPSHa.
Power Rating is cubic.
I think is better to see curves without any particular modification.
Por example if you have a Q-H for Mixted Flow Impeller
(Specific Speed 5000 to 6000), you should appreciate
if this pumps has inconsistent problem at rated point.

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