Recent content by RNPNR

These pumps are single vane impeller pumps used to transfer live fish from one tank to the other. These are not traditional centrifugal pumps. Hence the curves. Regarding calcs yes I used one incorrect value and I have corrected it now. I built this spreadsheet after your suggestions.

Here is what I calculated. We are changing diameter after the pump discharge. So I am assuming pressures change due to velocity change. After calculating pressure loss, I used affinity law to calculate new flow and head to make up for the pressure loss. One of the end condition is velocity...

Pump generates 36' head max. the point I am looking at 500 gpm at 30 ft head. I need to calculate the change in flow with 6" pipe for 9,10 and 11 m head. It is not the gain. Sorry for confusions.

Thanks Russ. I am going to add a sketch here. As you have mentioned that I need to know the pipe length. The flow rate and head I am referring to is from a pump curve with 8" inlet and outlet . I need to calculate the flow at different heads when using 6" pipe.

I have a pump running at 400rpm with 8" inlet and outlet with head 30 ft 500 gpm. Now I am planning to reduce the discharge line to 6" . Assuming the flow rate and speed constant the velocity in the pipe will increase. How do I calculate the change in head?