The flow-head and peformance graph for cetrifugal pumps

[waterskin7]

http://images1f.snapfish.com/232323232%7Ffp934%3Enu%3D333%3A%3E23%3A%3E2%3B7%3EWSNRCG%3D323%3A76%3C89%3B698nu0mrj

check on the link above , it is my workings on spreadsheet and data given .
basic : i am being told , that two centrifugal pumps , diameter given , speed given , are pumping water , through two parallel pipes , to a tank , they want to know the difference of pipe flow and power between using 1 pump and 2 pumps . performance data and darcy f are given for the pumps , these are data to plot a H-Q and efficiency graph .

what i did on the spreadsheet , is plotting the graph , get the parabolic curve equation , workout the A B C representing the properties of the pump , work out the x value , square it , then the number = pipe flow .

so where do those other informations comes in ? i mean the dia , length , darcy f .

 

[minger]

It seems that the only differences between the two systems are the pumps themselves? Is that correct? If so, then what information can be used to determine the differences? What adjustments will need to be made?

 

[CFDFEAGURU]

Darcy is the pipe friction factor. You get this value from reading a chart or performing a calculation.

 

[CFDFEAGURU]

The chart is the Moody Diagram and the equation is called the Colebrook equation.

http://en.wikipedia.org/wiki/Moody_diagram

 

[waterskin7]

my apology , what i think my homework was asking is , the difference of pipe flow between using one pump and using two .