SPECIFICATION SHEET • SI METRIC
CAT: MARINE

Hull Frictional Resistance (ITTC-1957)

Estimate frictional resistance (Rf) based on wetted surface area.

💡 Engineering Knowledge PrimerCalculate frictional resistance of a ship hull using the ITTC-1957 formula.
OPERATING LIMITS — ITTC skin-friction estimate only; verify reference length, appendages, form and correlation limits.
INPUT DESIGN PARAMETERS (SI)
m²
m
knots
kg/m³
m²/s
CALCULATED SPECIFICATION OUTPUT
Frictional Resistance (Rf)
385.2 kN
Reynolds Number784700000 1
Friction Coefficient (Cf)0.00158 1

Technical Methodology & Engineering Principles

GOVERNING EQUATION
Re = V × Lref / ν, Cf = 0.075 / (log10(Re) - 2)^2, Rf = 0.5 × ρ × V² × S × Cf
Assumptions & Scope

ITTC-1957 correlation line using the vessel reference length Lref and wetted area S; this estimates skin friction only.

Operating Range & Boundary

Use finite, physically meaningful inputs within the stated operating assumptions.