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Admiralty Coefficient Power

Contents

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Quick-look delivered power from displacement, speed and a ship-type Admiralty coefficient.

Formula

$$ P_D = \frac{\Delta^{2/3} \cdot V^3}{C} $$

Symbol legend

SymbolMeaningUnitSource
$P_D$Delivered power at the propellerkWresult
$\Delta$Displacement at design draftthydrostatic curves
$V$Service speedkndesign spec
$C$Admiralty coefficient - tanker/bulker 400–500, container 200–300, Ro-Pax 300–400, cruise 200–280-empirical / sister-ship fit

$C$ bundles hull form, frictional regime and propulsive efficiency into a single number. Calibrate it on sea-trial data whenever available.

Sources

  • Molland, Turnock & Hudson - Ship Resistance and Propulsion (Cambridge).
  • Bertram - Practical Ship Hydrodynamics (Elsevier).