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Freeman
12-06-2008, 11:25 PM
Flow Of Compressible Gas In A Horizontal Pipeline

The four commonly-used equations for long-distance gas pipeline are:
- Weymouth Equation
- Panhandle A
- Panhandle B
- AGA (American Gas Association)
Another equation was recently derived by Ohirhian via the manipulation of three basic equations : Weymouth, Colebrook and Reynold's number.
Each of the above five gasflow equations is based on some assumed expression for Friction factor , a dimensionless correlating function. m is the friction factor (also called the Moody friction factor) that is commonly tabulated in the Moody Charts. Quite often the Fanning Friction factor f is used: f = m/4.
The equations for each method is given below:



- Weymouth Equation:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%37%75%34%2d%5 3%5a%79%49%2f%41%41%41%41%41%41%41%41%41%5a%38%2f% 52%77%46%6b%50%4f%61%53%4b%5f%63%2f%73%31%36%30%30 %2d%68%2f%57%65%79%6d%6f%75%74%68%2e%67%69%66)

- Panhandle A:

( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%37%39%6f%2d%5 3%5a%7a%49%2f%41%41%41%41%41%41%41%41%41%61%45%2f% 53%58%64%6b%58%75%45%58%52%4c%34%2f%73%31%36%30%30 %2d%68%2f%50%61%6e%68%61%6e%64%6c%65%2e%67%69%66)
- Panhandle B:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%38%4b%6f%2d%5 3%5a%30%49%2f%41%41%41%41%41%41%41%41%41%61%4d%2f% 43%57%36%67%30%65%41%67%56%6c%4d%2f%73%31%36%30%30 %2d%68%2f%50%61%6e%68%61%6e%64%6c%65%42%2e%67%69%6 6)

- AGA (fully turbulent):

( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%38%68%6f%2d%5 3%5a%31%49%2f%41%41%41%41%41%41%41%41%41%61%55%2f% 6c%37%4b%6a%39%52%56%55%54%78%73%2f%73%31%36%30%30 %2d%68%2f%41%47%41%2e%67%69%66)

- Ohirhian:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%38%73%6f%2d%5 3%5a%32%49%2f%41%41%41%41%41%41%41%41%41%61%63%2f% 73%52%4b%39%69%7a%72%61%41%55%77%2f%73%31%36%30%30 %2d%68%2f%4f%68%69%72%68%69%61%6e%2e%67%69%66)


Where:
qsc = gas rate at standard condition, scf/d
P1 = inlet pressure, psia
P2 = outlet pressure, psia
Psc = pressure at standard condition, psia
Tsc = temperature at standard condition, &degR
Tm = mean temperature of line, &degR
Tg = ground temperature, &degR
μ = mean gas viscosity, cp
γ = mean gas relative density (air = 1)
Zm= mean gas compressibility factor
d = inside diameter of pipe, inches
L = pipe length, miles
E = pipeline efficiency
m = Moody friction factor
f = Fanning friction factor
Ft = transmission factor (√[1/f ])
ε = absolute roughness of pipe, inches
The mean values of the gas properties (Z & μ) are determined at the average pressure and temperature, derived as follows:


( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%2d%71%6f%2d%5 3%5a%33%49%2f%41%41%41%41%41%41%41%41%41%61%6b%2f% 64%72%37%51%70%59%6d%4f%7a%49%38%2f%73%31%36%30%30 %2d%68%2f%4d%65%61%6e%73%2e%67%69%66)


BIBLIOGRAPHY




Maddox R.N. & Lilly L.L.; Gas Conditioning & Processing, Volumes 2 & 3; Campbell Petroleum Series, Norman, Oklahoma, 1990.
Katz D.L. & Lee R.L.; Natural Gas Engineering - Production & Storage; McGraw-Hill Publ. Co., New York, 1990, chap. 6.
Ohirhian P.U.; Direct calculation of the gas volumetric flow rate in horizontal and inclined pipes; Paper SPE-37394, Soc. of Petroleum Eng., Richardson, Texas, 2002.

Freeman
12-06-2008, 11:29 PM
Flow Of Compressible Gas In An Inclined Pipeline

For a slightly inclined pipeline, flow rate predictions are obtained by the modification of the horizontal gas pipleline flow equations. The elevation change (positive uphill, negative downhill) is compensated for by adding the static head of gas column to the pressure loss calculation.
The four commonly-used equations for long-distance gas pipeline are:
- Weymouth Equation
- Panhandle A
- Panhandle B
- AGA (American Gas Association)
Another equation was recently derived by Ohirhian via the manipulation of three basic equations : Weymouth, Colebrook and Reynold's number.
Each of the above five gasflow equations is based on some assumed expression for Friction factor , a dimensionless correlating function. m is the friction factor (also called the Moody friction factor) that is commonly tabulated in the Moody Charts. Quite often the Fanning Friction factor f is used: f = m/4.
The equations for each method is given below with the eS and Le terms accounting for elevation change :

- Weymouth Equation:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%37%75%34%2d%5 3%5a%79%49%2f%41%41%41%41%41%41%41%41%41%5a%38%2f% 52%77%46%6b%50%4f%61%53%4b%5f%63%2f%73%31%36%30%30 %2d%68%2f%57%65%79%6d%6f%75%74%68%2e%67%69%66)

- Panhandle A:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%37%39%6f%2d%5 3%5a%7a%49%2f%41%41%41%41%41%41%41%41%41%61%45%2f% 53%58%64%6b%58%75%45%58%52%4c%34%2f%73%31%36%30%30 %2d%68%2f%50%61%6e%68%61%6e%64%6c%65%2e%67%69%66)


- Panhandle B:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%38%4b%6f%2d%5 3%5a%30%49%2f%41%41%41%41%41%41%41%41%41%61%4d%2f% 43%57%36%67%30%65%41%67%56%6c%4d%2f%73%31%36%30%30 %2d%68%2f%50%61%6e%68%61%6e%64%6c%65%42%2e%67%69%6 6)

-AGA (fully turbulent):


( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%38%68%6f%2d%5 3%5a%31%49%2f%41%41%41%41%41%41%41%41%41%61%55%2f% 6c%37%4b%6a%39%52%56%55%54%78%73%2f%73%31%36%30%30 %2d%68%2f%41%47%41%2e%67%69%66)

Ohirhian:
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%7a%38%73%6f%2d%5 3%5a%32%49%2f%41%41%41%41%41%41%41%41%41%61%63%2f% 73%52%4b%39%69%7a%72%61%41%55%77%2f%73%31%36%30%30 %2d%68%2f%4f%68%69%72%68%69%61%6e%2e%67%69%66)

Where:
qsc = gas rate at standard condition, scf/d
P1 = inlet pressure, psia
P2 = outlet pressure, psia
Psc = pressure at standard condition, psia
Tsc = temperature at standard condition, &degR
Tm = mean temperature of line, &degR
Tg = ground temperature, &degR
μ = mean gas viscosity, cp
γ = mean gas relative density (air = 1)
Zm= mean gas compressibility factor
d = inside diameter of pipe, inches
L = pipe length, miles
Le = effective pipe length, miles
ΔH = Change in elevation between inlet & outlet (ft)
E = pipeline efficiency
m = Moody friction factor
f = Fanning friction factor
Ft = transmission factor (√[1/f ])
ε = absolute roughness of pipe, inches
( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%30%41%56%6f%2d%5 3%5a%34%49%2f%41%41%41%41%41%41%41%41%41%61%73%2f% 33%4a%35%76%64%6d%6c%2d%63%65%49%2f%73%31%36%30%30 %2d%68%2f%53%2b%4c%2e%67%69%66)

The mean values of the gas properties (Z & μ) are determined at the average pressure and temperature, derived as follows:


( 2e%62%6c%6f%67%67%65%72%2e%63%6f%6d%2f%5f%5f%6c%6d %71%76%47%39%43%65%51%73%2f%52%31%30%41%6b%34%2d%5 3%5a%35%49%2f%41%41%41%41%41%41%41%41%41%61%30%2f% 68%51%39%57%54%41%42%45%78%4f%38%2f%73%31%36%30%30 %2d%68%2f%50%2b%54%2e%67%69%66)
BIBLIOGRAPHY




Maddox R.N. & Lilly L.L.; Gas Conditioning & Processing, Volumes 2 & 3; Campbell Petroleum Series, Norman, Oklahoma, 1990.
Katz D.L. & Lee R.L.; Natural Gas Engineering - Production & Storage; McGraw-Hill Publ. Co., New York, 1990, chap. 6.
Tian S. & Adewusi M.A.; Development of analytical design equation for gas pipelines; Paper SPE-24861, Soc. of Petroleum Eng., Richardson, Texas, 1992.
Ohirhian P.U.; Direct calculation of the gas volumetric flow rate in horizontal and inclined pipes; Paper SPE-37394, Soc. of Petroleum Eng., Richardson, Texas, 2002.

icqaa
12-26-2008, 02:45 PM
can u translate it in to international units?
and i want to know how to convert BWRS EOS's unit ,and use it in to gas pipeline simulation?
thanks

mirfan389
12-26-2008, 09:59 PM
How can we find the diameter of compressed natural gas pipe line if flow rate and pressure is given.
If anyone has ebook related to this, please inform soon.
Muhammad Irfan

icqaa
12-27-2008, 04:45 AM
i have the Chinese version, do u want to have a look?