Reference:  Hydraulics of Pipeline Systems, 2000, CRC Press LLC, Bruce E. Larock, Rowland W. Jeppson, Gary Z. Watters, Page 220, Example problem 5.30


Pipe Flow Expert File: Case_08_Water_Find_Pump_Head_Required.pfe


Problem Description: 

A small pipe network connects two reservoirs which have different water surface levels.


The main water source (lowest reservoir) has a surface elevation of 90 ft.

The highest reservoir has a surface elevation of 100 ft.


At each node in the pipe network water is removed from the system.


A pump supplies water from the lowest reservoir to the system.


When all out flow demands are being met calculate 

the pump head required to supply the network without

any flow entering or leaving the highest reservoir.


A screenshot of a computer??Description automatically generated


Fluid Data: Water at 41° F. (5° C Assumed)


Result Comparison: 


Data Item

Published data

Pipe Flow Expert

Pump head required (ft)

51.0

50.631   (100.000 – 49.369) 


Commentary: 

The published data and the calculated results compare very well.

To model this situation in Pipe Flow Expert a fixed head increase pump was used to add 100 ft hd to the system.

A flow control valve was placed on the pipe leading to the highest reservoir, to represent the requirement that zero flow should occur in this pipe the flow control flow rate was 0.0001 ft³/s (smallest allowable value).

The differential head introduced by the flow control valve was subtracted from the fixed 100 ft head added to the system to obtain the actual head that would be required from actual pump that would be installed in the system.