Hydrodynamic Analysis Method
Holtrop & Mennen Resistance Prediction
Statistical regression method — J. Holtrop & G.G.J. Mennen (1982 & 1984)
The Holtrop–Mennen method is a widely-adopted statistical regression technique for estimating the total calm-water resistance of conventional displacement ship hulls. Derived from model tests and full-scale trials, it decomposes total resistance into physically meaningful components:
Total Ship Resistance
$$R_T = R_F(1 + k_1) + R_{APP} + R_W + R_B + R_{TR} + R_A$$
Each term represents a distinct physical contribution to bare-hull and appendage drag in calm water.
Frictional Resistance ($R_F$)
Based on the ITTC-1957 friction correlation line applied to the wetted surface area $S$, with form factor $(1+k_1)$ capturing the viscous pressure resistance of the hull form:
ITTC-1957 Correlation Line
$$R_F = \frac{1}{2}\rho V^2 S \cdot C_F$$
The friction coefficient is driven by: Cf = 0.075 / (log(Re) − 2)², and $k_1$ from $L$, $B$, $T$, $L_{CB}$, $C_P$, $C_M$.
Wave-Making Resistance ($R_W$)
The most complex component, valid for $0.10 \leq F_n \leq 0.55$. It captures the hull's bow and stern wave interactions through empirical regression coefficients:
Wave Resistance (Holtrop Form)
$$R_W = c_1 c_2 c_5 \nabla \rho g \, e^{\,m_1 F_n^{d} + m_2 \cos(\lambda F_n^{-2})}$$
Coefficients c₁–c₅, m₁, m₂, λ, d are regression functions of principal dimensions and form coefficients.
Additional Components
Appendage resistance $R_{APP}$ uses equivalent flat-plate drag with individual $1+k_2$ form factors. Bulbous bow ($R_B$) and transom ($R_{TR}$) are optional additive corrections. Correlation allowance $R_A$ covers hull roughness and scale effects.