Engineering

Helicopter rotor: lift from moving air

Change collective pitch and rotor speed; compare blade-element thrust, induced flow and the power needed to hover.

Actual application image

Try this

Raise collective pitch or rotor speed. Compare thrust with the weight; blue streaks indicate downward induced air.

The model and its limits

Uniform-inflow hover blade-element model with bounded lift coefficients. Vertical travel is limited to an 8 m teaching stand. No forward-flight or vortex-ring prediction.

Equations used in the module

Equations
T = 2 rho A v_i^2
P_induced = T v_i

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