Moody Diagram

Calculate fluid flow friction coefficients from a Moody diagram. Determines the SI-based Moody friction factor (λ) used in the Darcy-Weisbach major loss equation based on Reynolds number and relative roughness.

Moody Diagram Calculator

Calculate fluid flow friction coefficients using the SI-based Moody diagram approach.

Inputs

Provide the following parameters to determine the friction factor:

  • Absolute Roughness (k): Surface roughness in meters
  • Hydraulic Diameter (d_h): Pipe or duct equivalent diameter in meters
  • Reynolds Number (Re): Flow Reynolds number (dimensionless)

Output

  • Relative Roughness (r): Calculated as k / d_h
  • Friction Factor (λ): Estimated from the Moody diagram

Note: For transient flow (2300 < Re < 4000), interpolate between laminar and turbulent values.

Calculator

Inputs

Results

Relative Roughness (r)-- -
Friction Factor (λ)-- -
Moody Diagram | MEPKit Engineering Tools | MEPKit