HomeCalculatorsFlettner Rotor - Drive Power

Flettner Rotor - Drive Power

Electric motor input power to spin a Flettner rotor at the design RPM - 1–3 % of generated thrust energy.

FlettnerRotor power
Tip speed
47.1m/s
Drive power (screening)
2,884.3kW

Formula, assumptions, and limits

$$P = \tfrac{1}{2} \rho_a C_D D H V_t^3$$

$C_D$ ≈ 0.3 for smooth cylinder in spin. Real drive also has bearing/seal losses. Manufacturers quote 200–600 kW drive per rotor.

Symbol legend

SymbolMeaningUnitSource
$V_t$Rotor tip speedm/sπDn
$D, H$Rotor diameter / heightmmaker spec

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