Pipe Flow Expert Software Non Compressible Results Verification - Case 14: Water - Net Positive Suction Head Available - Example 2

Reference:  Cameron Hydraulic Data , 18th Edition, 1994, Ingersoll-Dresser Pumps. Page 1-14, Example No 3.

Pipe Flow Expert File: Case_14_Water_Net_Positive_Suction_Head_Available.pfe

Problem Description: 

A pump is used to deliver water to a distribution system.

The friction loss through the suction line is stated to be 2.92 ft head.

The water source is 10 ft above the pump.

The pressure on the surface of the fluid is atmospheric, 14.696 psi.a.

The fluid is boiling water at 212°F.

Find the NPSHa and the suction head available.

Fluid Data: Water at 212°F at sea level.

Result Comparison: 

Commentary: 

The published data and the calculated results compare well.

This is a very simple example where the friction loss through the pipes is stated.

To model this situation in Pipe Flow Expert, pipe diameters and pipe lengths have been set to give a total friction loss in the suction pipes of 2.92 ft hd, when the pump flow rate is set to 5 ft³/sec.

The discharge pipework was modeled with a similar size pipe and a 10 ft lift on the discharge side of the pump.

This allows the HGL at the node where the pump has been located to be used for comparison with the published suction head available.

Note: The vapor pressure of the boiling fluid is equal to the fluid surface pressure, so the pressure on the fluid surface does not add to the NPSHa.