Simple Question re: Piping System Curve

[jbuck123]

Let's say I have modeled the system curve for a single temporary water pipeline and am satisfied with what I have plotted on a line chart and am going to plot some different centrifugal pump curves on top of it to see where the different operating points fall. If there is another temporary water pipeline running parallel to the first one, with exactly the same specifications, and I were to connect the two pipelines together with a common manifold, what effect would this have on the system curve? This would flatten out the system curve, right?

 

[BigInch]

It would tend to flatten out the curve.
System curves are similar to a parabola, Head, H = k * Q^n + Ho Where Q = flow (plotted on the x axis), and Ho is initial static head.
In your case with two identical pipelines connected to the same pump manifold, k would essentially be cut in half when the second pipeline is connected. Also note that the second pipeline must also pass the same elevations and have equivalent outlet conditions as well; same outlet elevation, flowrate and pressure.

 

[LittleInch]

Or if these are truly the same, Q in either pipe is half of the total. Friction Head will therefore fall by a quarter for the same total flow compared to a single pipe.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way