Darcy Friction Factor

The Darcy friction factor, often denoted by f, is a dimensionless parameter used in fluid mechanics to characterize the resistance to flow in a pipe or conduit.

The Darcy friction factor is commonly used in the Darcy-Weisbach equation, which relates the pressure drop or head loss in a pipe to the flow rate, pipe diameter, and fluid properties.

Darcy friction factor is proportional to shear stress at pipe/conduit wall as number of velocity heads and is used in momentum transfer in general and turbulent flow calculations in particular. It is equivalent to (4) times Fanning’s friction factor. It is normally defined in one of the following forms

darcy number Calculator

Darcy Friction Factor Calculators

Calculator 1

g (Acceleration due to gravity):
d (Diameter):
ΔP (Pressure drop):
ρ (Density):
V (Velocity):
L (Length):

Calculator 2

g (Acceleration due to gravity):

d (Diameter):

ΔP (Pressure drop):

ΔL (Length difference):

ρ (Density):

V (Velocity):

Calculator 3

gc (Dimensional constant):

d (Diameter):

ΔP (Pressure drop):

ρ (Density):

G (Mass velocity):

L (Length):

Calculator 4

gc (Dimensional constant):

d (Diameter):

ΔP (Pressure drop):

ΔL (Length difference):

ρ (Density):

G (Mass velocity):

Where:
d
=
Diameter
delta-P
=
Pressure drop
dP/dL
=
Pressure drop per unit length
gc
=
Dimensional constant
G
=
Mass velocity
L
=
Length
rho
=
Density
V
=
Velocity

The Darcy friction factor depends on various factors such as the Reynolds number, relative roughness of the pipe, and flow regime. It’s typically determined using empirical correlations or obtained from friction factor charts for specific flow conditions.
The Darcy friction factor is crucial in determining the energy losses associated with fluid flow in pipes and is widely used in the design and analysis of piping systems, HVAC systems, and hydraulic networks. It plays a significant role in optimizing system performance and ensuring efficient fluid transport.