The analysis for predicting axial thrust in a single stage open impeller pump is straight forward. Is the same formula used when putting these pumps in series? Specifically, the last pump in my series will see 400 psi inlet pressure. Is it as simple as plugging in my 400 psi for P inlet? That...
Yes, we do see a vortex too close to the inlet for comfort.
We are subtracting the inlet conditions and taking into account the velocity head. We have inlet pressure gage, discharge pressure gage and flow meter. Hope to rerun the test Monday with the discharge moved further away.
Thanks for...
I will clairify, the pump is being run on a test rig, I believe the discharge pipe is too close to the inlet and may be introducing turbulance/air into the inlet. There is no NPSH issue as it is an open tank with 6' of tubing before the pump and flooded.
I think you hit on something. The pumps that are fine are much smaller. We are going to check the turbulence from the discharge and how it may effect the inlet.
Thanks, I will let you know.
Yes, the head diverges from the published curve as we go out in flow for one of our model pumps. At shutoff we match-up to the published pretty good but it drops off as we go out in flow. Other model pumps of ours match the published curve well using the same test stand. Velocity head data was...
what would cause one of our simi shrouded impeller centrifugal pumps to loose head as we go out on the flow? The test stand has been double checked and everything else with the pump seems normal.
