Speed–Power Curve Generator

ITTC ’57 friction + Froude-based residuary. Table + live curve. Separate PNG/PDF exports for both.

If blank, S ≈ 1.7 × LWL × B.
Adds to ITTC ’57 Cf.
Applied to delivered power.
Speed–Power Table

Area S: — m²

Method: ITTC ’57 friction + CR(Fn) with CR = 0.004 + 0.0025·Fn2.5.

Sea margin: —% applied to PD.

Enter geometry & range, then Generate. Table shows coefficients & power at each speed.
V (kn) Fn (–) Re (–) Cf Cr RT (kN) PD (kW) PD,marine (kW)
Report: Speed–Power Curve Generator
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Speed–Power Curve (Plot)
Shows PD (kW) vs Speed (kn). Marine margin not shown.
Formula Notes

Friction (ITTC ’57): \( C_f = \dfrac{0.075}{(\log_{10} Re - 2)^2} + \Delta C_f \)

Residuary correlation: \( C_R = 0.004 + 0.0025\,F_n^{2.5} \)

Total resistance: \( R_T = 0.5\,\rho\,V^2\,S\,(C_f + C_R) \)

Delivered power: \( P_D = \dfrac{R_T\,V}{\eta_D} \).

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