Liquid Pipeline Pressure Loss From The Darcy Weisbach Equation

Calculate single phase liquid pipeline pressure loss using the Darcy Weisbach equation.

`Po = P - (fd L / (ID) + K) 1/2 ρ V^2 + ρ g (zi - zo) `

where :

Po = outlet pressure
P = inlet pressure
fd = Darcy friction factor
L = piping length
ID = piping inside diameter
K = total friction loss factor for fittings
ρ = fluid density
V = fluid velocity
g = gravity constant
zi = inlet elevation
zo = outlet elevation

The Darcy friction factor can be calculated for

Hagen-Poiseuille laminar flow equation
original Colebrook White equation
modified Colebrook White equation
Prandtl Nikuradse smooth pipe equation
Blasius smooth pipe equation
Colebrook smooth pipe equation
Miller smooth pipe equation
Konakov smooth pipe equation
Von Karman rough pipe equation

For low Reynolds numbers Re < 2000, the fluid flow is laminar and the Darcy friction factor should be calculated using the Hagen-Poiseuille laminar flow equation. For high Reynolds numbers Re > 4000, the fluid flow is turbulent and the Darcy friction factor should be calculated using one of the turbulent flow equations. In the transition region 2000 < Re < 4000, the flow is unstable and the friction loss cannot be reliably calculated. The minor loss K factor is used to account for pipeline fittings such as bends, tees, valves etc..

The calculators use the Darcy-Weisbach pressure loss equation. The Fanning friction factor is used with the Fanning pressure loss equation. The transmission factors are commonly used for gas flow. The results for the Darcy and Fanning equations are identical provided that the correct friction factor is used.

Change Module :

Liquid Pipeline Chemical Dose Rate Calculation Module
Liquid Pipeline Fluid Density Viscosity And Specific Gravity Calculation Module
Liquid Pipeline Fluid Mass And Volume Calculation Module
Liquid Pipeline Fluid Velocity And Flow Rate Calculation Module
Liquid Pipeline Local Pressure Calculation Module
Liquid Pipeline Minor Loss Factor Calculation Module
Liquid Pipeline Pressure Loss From The AGA Equation Calculation Module
Liquid Pipeline Pressure Loss From The Moody Diagram Calculation Module
Liquid Pipeline Unit Weight Calculation Module
Liquid Pipeline Vent Calculation Module
Liquid Rectangular Duct Pressure Loss Calculation Module
Water Open Channel Or Culvert Flow Rate From The Manning Equation Calculation Module
Water Pipeline Pressure Loss From The Hazen Williams Equation Calculation Module
All

Related Modules :

Fluid Density And Volume Calculation Module
Line Pipe Cross Section Calculation Module
Liquid Kinematic And Dynamic Viscosity Calculation Module
More Pipeline Schedule Modules

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Links : ±

CALCULATOR : Single Phase Liquid Pipeline Pressure Loss From Moody Diagram [FREE] ±

Calculate liquid pipeline outlet pressure from flow rate and diameter using the Moody diagram.

The Moody diagram combines the Hagen-Poiseuille laminar flow equation with the Colebrook White turbulent flow equation (either the original Colebrook White equation or the modified Colebrook White equation).

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
visctype : Viscosity Type
- μu : User Defined Dynamic Viscosity
- νu : User Defined Kinematic Viscosity
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
- Reu : User Defined Reynolds Number
rfactype : Pipe Internal Roughness Type
- ru : User Defined Surface Roughness
- rru : User Defined Relative Roughness
fdtype : Darcy Friction Factor Type
- fdu : User Defined Darcy Friction Factor
ρ : Fluid Density
L : Pipe Length
K : Minor Loss K Factor
zi : Inlet Elevation Relative To Datum
zo : Outlet Elevation Relative To Datum
Pi : Inlet Pressure

Tool Output

ΔP : Friction Pressure Loss
μ : Dynamic Viscosity
ID : Inside Diameter
M : Mass Flowrate
Po : Outlet Pressure
Q : Volume Flowrate
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
ff : Fanning Friction Factor
rr : Surface Roughness Ratio
td : Darcy Transmission Factor
tf : Fanning Transmission Factor

CALCULATOR : Single Phase Liquid Pipeline Pressure Loss From Prandtl Nikuradse Blasius Colebrook Miller Konakov And Von Karman Equation [FREE] ±

Calculate liquid pipeline outlet pressure from flow rate and diameter.

The Darcy-Weisbach friction factor may be calculated using either the Hagen-Poiseuille laminar flow equation, the original Colebrook White equation, the modified Colebrook White equation, the Prandtl Nikuradse smooth pipe equation, the Blasius smooth pipe equation, the Colebrook smooth pipe equation, the Miller smooth pipe equation, the Konakov smooth pipe equation, the Von Karman rough pipe equation, or user defined.

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
visctype : Viscosity Type
- μu : User Defined Dynamic Viscosity
- νu : User Defined Kinematic Viscosity
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
- Reu : User Defined Reynolds Number
rfactype : Pipe Internal Roughness Type
- ru : User Defined Surface Roughness
- rru : User Defined Relative Roughness
fdtype : Darcy Friction Factor Type
- fdu : User Defined Darcy Friction Factor
ρ : Fluid Density
L : Pipe Length
K : Minor Loss K Factor
zi : Inlet Elevation Relative To Datum
zo : Outlet Elevation Relative To Datum
Pi : Inlet Pressure

Tool Output

ΔP : Friction Pressure Loss
μ : Dynamic Viscosity
ID : Inside Diameter
M : Mass Flowrate
Po : Outlet Pressure
Q : Volume Flowrate
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
ff : Fanning Friction Factor
rr : Surface Roughness Ratio
td : Darcy Transmission Factor
tf : Fanning Transmission Factor

CALCULATOR : Water Pipeline Pressure Loss From Hazen Williams Equation [FREE] ±

Calculate water pipeline outlet pressure from flow rate and diameter using the Hazen-Williams equation.

The Hazen Williams equation was developed for water pipelines. The Hazen Williams roughness coefficient C can either use predefined values, or user defined.

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
cfactype : Pipe Internal Roughness Type
- Cu : User Defined Pipe Internal Roughness Factor
ρ : Fluid Density
L : Pipe Length
zi : Inlet Elevation Relative To Datum
zo : Outlet Elevation Relative To Datum
Pi : Inlet Pressure

Tool Output

ΔP : Friction Pressure Loss
C : Hazen Williams Roughness Factor
ID : Inside Diameter
M : Mass Flowrate
Po : Outlet Pressure
Q : Volume Flowrate
V : Fluid Velocity
fd : Equivalent Darcy Friction Factor
r : Hydraulic Radius
s : Hydraulic Grade Line Slope (ΔH/L)

CALCULATOR : Water Pipeline Pressure Loss From Moody Diagram [FREE] ±

Calculate water pipeline outlet pressure from volume flow rate and diameter using the Moody diagram.

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
wtype : Water Type
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
- Reu : User Defined Reynolds Number
rfactype : Pipe Internal Roughness Type
- ru : User Defined Surface Roughness
- rru : User Defined Relative Roughness
fdtype : Darcy Friction Factor Type
- fdu : User Defined Darcy Friction Factor
L : Pipe Length
K : Minor Loss K Factor
zi : Inlet Elevation Relative To Datum
zo : Outlet Elevation Relative To Datum
Pi : Inlet Pressure

Tool Output

ΔP : Friction Pressure Loss
μ : Water Dynamic Viscosity
ρ : Water Density
ID : Inside Diameter
M : Mass Flowrate
Po : Outlet Pressure
Q : Volume Flowrate
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
ff : Fanning Friction Factor
rr : Surface Roughness Ratio
td : Darcy Transmission Factor
tf : Fanning Transmission Factor

CALCULATOR : Single Phase Liquid Pipeline Pressure Loss From AGA Equation [FREE] ±

Calculate liquid pipeline outlet pressure from volume flow rate and diameter using the AGA equation.

The AGA equation was developed for hydrocarbon pipelines. Minor losses are calculated from the pipe bend index (bend degrees per mile).

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
visctype : Viscosity Type
- μu : User Defined Dynamic Viscosity
- νu : User Defined Kinematic Viscosity
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
- Reu : User Defined Reynolds Number
rfactype : Pipe Internal Roughness Type
dfactype : AGA Drag Factor Type
- θu : User Defined Total Bend Angle
- BIu : User Defined Bend Index
- Dfu : User Defined Pipe Drag Factor
fdtype : Darcy Friction Factor Type
- fdu : User Defined Darcy Friction Factor
ρ : Fluid Density
L : Pipe Length
zi : Inlet Elevation Relative To Datum
zo : Outlet Elevation Relative To Datum
Pi : Inlet Pressure

Tool Output

ΔP : Friction Pressure Loss
μ : Dynamic Viscosity
Df : AGA Pipe Drag Factor
ID : Inside Diameter
M : Mass Flowrate
Po : Outlet Pressure
Q : Volume Flowrate
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
ff : Fanning Friction Factor
rr : Surface Roughness Ratio
td : Darcy Transmission Factor
tf : Fanning Transmission Factor

CALCULATOR : Single Phase Liquid Pipeline Pressure Loss General [FREE] ±

Calculate general liquid pipeline outlet pressure from flow rate and diameter using the Moody diagram.

Tool Input

fdtype : Darcy Friction Factor Type
- fdu : User Defined Darcy Friction Factor
ρ : Fluid Density
ID : Pipe Inside Diameter
r : Pipe Inside Surface Roughness
L : Pipe Length
K : Minor Loss K Factor
zi : Inlet Elevation Relative To Datum
zo : Outlet Elevation Relative To Datum
Pi : Inlet Pressure
μ : Dynamic Viscosity
Q : Volume Flowrate

Tool Output

ΔP : Friction Pressure Loss
M : Mass Flowrate
Po : Outlet Pressure
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
rr : Surface Roughness Ratio

CALCULATOR : Single Phase Liquid Pipeline Darcy Friction Factor [FREE] ±

Calculate liquid pipeline Darcy Weisbach friction factor from Renolds number and pipe roughness.

The Fanning friction is equal to the Darcy friction factor divided by four. The transmission factor equals the inverse of the square root of the friction factor.

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
visctype : Viscosity Type
- μu : User Defined Dynamic Viscosity
- νu : User Defined Kinematic Viscosity
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
- Reu : User Defined Reynolds Number
rfactype : Pipe Internal Roughness Type
- ru : User Defined Surface Roughness
- rru : User Defined Relative Roughness
fdtype : Darcy Friction Factor Type
- fu : User Defined Darcy Friction Factor
ρ : Fluid Density

Tool Output

μ : Dynamic Viscosity
ID : Inside Diameter
M : Mass Flowrate
Q : Volume Flowrate
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
ff : Fanning Friction Factor
rr : Surface Roughness Ratio
td : Darcy Transmission Factor
tf : Fanning Transmission Factor

CALCULATOR : Single Phase Liquid Pipeline Equivalent Length And K Factor [FREE] ±

Calculate single phase liquid pipeline minor loss factors through a fitting (valve, tee, reducer, enlarger etc...).

Enter the minor loss factor as either the K factor, the equivalent length, the equivalent diameters, or the flow coefficient (Av, Kv, Cv units). Change flow coefficient units on the setup page. The Darcy friction factor is required to calculate the equivalent length and equivalent diameters. Use either the laminar flow equation, the original Colebrook White equation, or the modified Colebrook White equation from the Moody diagram. The Darcy friction factor can also be user defined.

Tool Input

schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
visctype : Viscosity Type
- μu : User Defined Dynamic Viscosity
- νu : User Defined Kinematic Viscosity
voltype : Fluid Flow Rate Type
- Qu : User Defined Volume Flow Rate
- Mu : User Defined Mass Flow Rate
- Vu : User Defined Fluid Velocity
- Reu : User Defined Reynolds Number
rfactype : Pipe Internal Roughness Type
- ru : User Defined Surface Roughness
- rru : User Defined Relative Roughness
kfactype : Minor Loss Factor Type
- ku : User Defined Minor Loss K Factor
- lu : User Defined Minor Loss Length
- lodu : User Defined Minor Loss Diameters
- fvu : User Defined Minor Loss Flow Coefficient
fdtype : Darcy Friction Factor Type
- fdu : User Defined Darcy Friction Factor
ρ : Fluid Density

Tool Output

μ : Dynamic Viscosity
ID : Inside Diameter
K : Minor Loss K Factor
M : Mass Flowrate
Q : Volume Flowrate
Re : Reynolds Number
V : Fluid Velocity
cvg : Convergence Factor (≅ 1)
fd : Darcy Friction Factor
ff : Fanning Friction Factor
fv : Minor Loss Flow Coefficient
l : Minor Loss Equivalent Length
lod : Minor Loss Diameters
rr : Surface Roughness Ratio
td : Darcy Transmission Factor
tf : Fanning Transmission Factor