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Cube Law Fuel Ratio

Quick ratio of main-engine fuel at two speeds using V^n scaling. Screened separately from the voyage-slow-steaming page for one-liner use.

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Formula, assumptions, and limits

FnewFref=(VnewVref)n\frac{F_\text{new}}{F_\text{ref}} = \left(\frac{V_\text{new}}{V_\text{ref}}\right)^n
SymbolMeaningUnit
Vref,VnewV_\text{ref}, V_\text{new}Speedskn
nnSpeed exponent (3 default)
RatioRatioNew-to-ref fuel fraction

Source: MAN ES - Basic Principles of Ship Propulsion

In short

Quick ratio of main-engine fuel at two speeds using V^n scaling.

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