Gas Pipeline Calculator

Solution/ Design Parameter based on Transmission Factor Calculation Method

The PPI Gas Pipeline Flow Calculator uses the General Flow Equation -

\displaystyle Q = \frac{C_1}{\sqrt{f}}*\left(\frac{T_{b}}{P_{b}}\right)*\left[ \frac{\left( P_1^2-P_2^2-H_{c}\right)}{\left(SG*T_{a}*L*Z_{a}\right)}\right]^{0.5}*D^{2.5}*E

where,

\displaystyle H_c = C_2*SG*\left(H_2-H_1\right)*P_{avg}^2/\left(Z_a*T_a\right)

\displaystyle C_1 = 77.58

\displaystyle C_2 = 0.0375

where,

• Q = Flow Rate [ SCFD ]
• F = Transmission Factor
• Tb = Base Temperature [ °R ]
• Ta = Average Temperature [ °R ]
• Pb = Base Pressure [ psia ]
• P1 = Pressure at Inlet of pipe [ psia ]
• P2 = Pressure at Outlet of pipe [ psia ]
• D = Pipe Inside Diameter [ inch ]
• L = Pipe Length [ miles ]
• SG = Specific Gravity of Gas
• Za = Average Gas Compressibility Factor
• Pavg = Average Flow Pressure [ psia ]
• E = Pipeline Efficiency
• H1 = Elevation at Point 1 [ feet ]
• H2 = Elevation at Point 2 [ feet ]

Friction Factor, f, can be estimated using following relations -

Colebrook-White (Modified)

\displaystyle \frac{1}{\sqrt{f}}= -2*Log_{10}\left[ \frac{\epsilon}{3.7}+\frac{2.825}{\left(Re*\sqrt{f}\right)}\right]

IGT Improved

\displaystyle \frac{1}{\sqrt{f}}=2.3095*Re^{0.1}

Chen

\displaystyle \frac{1}{\sqrt{f}}=-2\log_{10}\left(\frac{\epsilon}{3.7065} - \frac{5.0452}{Re}*\log_{10}C\right)

where,

\displaystyle C=\frac{\epsilon^{1.1096}}{2.8257}+\frac{7.149}{Re^{0.8961}}

Gouder - Sonnad

\displaystyle \frac{1}{\sqrt{f}}=0.8686*\ln\left[\frac{0.4587*Re}{{C-0.31}^{C/(C+1)}}\right]

where,

\displaystyle C = 0.124*Re*\epsilon+\ln\left(0.4587*Re\right)

Renouard

\displaystyle \frac{1}{\sqrt{f}}=0.21*{Re}^{-0.2}, Re < 4000

\displaystyle \frac{1}{\sqrt{f}}=2.4112*{Re}^{0.09}, 4000 < Re < 4e6

\displaystyle \frac{1}{\sqrt{f}}=2.1822*{Re}^{0.1}, Re > 4e6