| CALC : Flow : Friction 041 : Turbulent Gas Flow Friction Pressure Loss From Mole Flow Rate and Compressibility Factor Z : Calculator
Description : Calculate the friction pressure loss ΔPf from the mole flow rate N for turbulent gas flow in a pipeline.
Discussion : The pipeline diameter, fluid compressibility factor Z, fluid temperature and fluid viscosity are assumed to be constant along the pipeline. Changes in elevation and dynamic pressure are ignored. The k factor value accounts for the minor losses due to bends tees and valves etc in the pipeline. The k value should be relative to the pipeline diameter. The function CalcFMoody() calculates the Darcy friction factor f from the Reynolds number Re and the relative roughness Rr. To verify the output from function CalcFMoody() check that the value fchk equals f. For turbulent flow check that the Reynolds number Re > 2000.
Figures :
Input Variables :
- μ = Fluid Dynamic Viscosity
- D = Section Internal Diameter
- K = Dimensionless Friction Pressure Loss Factor K
- L = Section Length
- N = Fluid Mole Flow Rate
- Pi = Fluid Inlet Absolute Pressure
- R = Universal Gas Constant
- T = Fluid Absolute Temperature
- Z = Fluid Dimensionless Compressibility Z Factor
- mw = Fluid Mole Weight or Molar Mass
- r = Section Internal Roughness
Output Variables :
- ΔPf = Fluid Friction Pressure Loss
- ρi = Inlet Fluid Density
- ρo = Outlet Fluid Density
- Po = Fluid Outlet Absolute Pressure
- Re = Fluid Dimensionless Reynolds Number
- Rr = Internal Pipeline Dimensionless Roughness Number
- Vi = Inlet Fluid Velocity
- Vo = Outlet Fluid Velocity
- f = Dimensionless Darcy Friction Pressure Loss Factor f
- fchk = Check Dimensionless Darcy Friction Factor f
- vmi = Inlet Fluid Mole Volume
- vmo = Outlet Fluid Mole Volume
Calculation :
Rr = r / D
Re = ( 4 mw N ) / ( π μ D )
f = CalcFMoody( Re , Rr )
fchk = 0.25 / log10( Rr / 3.7 + 2.51 / ( Re √( f ) ) ) 2
Po = √( Pi 2 - ( f L / D + K )( 16 mw Z R T N 2 ) / ( π 2 D 4 ) )
ΔPf = Pi - Po
vmi = ( Z R T ) / Pi
vmo = ( Z R T ) / Po
ρi = mw Pi / ( Z R T )
ρo = mw Po / ( Z R T )
Vi = ( 4 N Z R T ) / ( π Pi D 2 )
Vo = ( 4 N Z R T ) / ( π Po D 2 )
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