Calm-Water Hull Resistance

Total resistance & effective power (Holtrop–Mennen 1982)

Hull main dimensions

Hull type

Length unit

Length on waterline LWL

Moulded beam B

Moulded draft T

Forward draft TF

Displaced volume ∇

Block coefficient CB: — Prismatic CP: —

Hull form coefficients

Midship coefficient CM

—

Waterplane coefficient CWP

—

LCB (%L, + forward)

Stern shape

Advanced (optional)

Set ABT/AT to 0 for no bulb and dry transom. Add appendages via the schedule below.

Bulb transverse area ABT

m²

Bulb centroid height hB

Immersed transom area AT

m²

Appendage schedule (area · (1+k2))

Each appendage adds ΔRT = ½ρV²·(1+k2)·S·C_F; the schedule feeds R_APP into the resistance result.

Environment

Water

Water density ρ

kg/m³

Kinematic viscosity ν

×10⁻⁶ m²/s

Speed unit

Service & environmental corrections

Simplified preliminary-design corrections applied to the design-speed resistance.

Wind drag (Taylor)

Wind speed

Frontal area

m²

Added resistance in head seas

Significant wave height

Factor C_AW

—

Fouling / roughness ΔCf

ΔCf

—

Shallow water

Water depth

Run

Speed (design)

from

steps

—

Resistance summary at design speed

Appendage resistance breakdown

Per-item ΔRT and their share of the total appendage resistance at design speed.

Resistance & power curves

Speed sweep table

Method: Holtrop–Mennen (1982). Valid mainly for conventional displacement hulls.
ν normally 1.139×10⁻⁶ m²/s for seawater at 15 °C.
If a coefficient is auto it is derived from the block coefficient.