Reference: Gas Pipeline Hydraulics, 2005, CRC Press, E. Shashi Menon, Chapter 2, page 71 Example 19


Pipe Flow Expert File: Case_11_IGT_Equation.pfe


Problem Description: 

Find the flow rate in a natural gas pipeline 15 miles long. 

The pipe is NPS 16 with a 0.250 inch wall thickness. 

The inlet & outlet pressures are 1000 psi.g & 800 psi.g, respectively. 

The pipeline efficiency is 0.95.  

Average gas temperature is 80 °F.  

Gas gravity = 0.6, viscosity = 0.000008 lb/ft-sec.  

The compressibility factor Z = 0.90.

Use the IGT equation to calculate the flow rate.


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Pipe Flow Expert Parameters:


Fluid Data: Gas with specific gravity 0.6 (0.044 lb/ft3), 80 °F, 0.00 psi.g, viscosity 0.0119 centipoise.

Pipe Data: Roughness 700 micro-inches.

Calculation Method: IGT (Institute of Gas Technology) Isothermal Flow equation, Node Adjust Method.M

Standard Atmospheric Model: 60°F, 14.696 psi.

Gas Physical Model: Real Gas Model (Ideal Gas Law with compressibility factor Z=0.9)


Result Comparison: 


Data Item

Published data

Pipe Flow Expert

Flow rate MMSCFD

263.1

263.37


Commentary: 

The published data and the calculated results compare well.