Wind Turbine Aerodynamics - Lecture

11 May 2026, Galih Bangga

Fundamental Equations of wind power

Wind Power - wind kinetic energy per unit time

$$ P_w = 0,5 \cdot \rho \cdot V^3 \cdot A $$

Power is proportional to $\text{velocity}^3$ and proportional to $\text{radius}^2$

Power Coefficient - power generated by the turbine over the power potential of the wind

$$ C_p = \frac{P_T}{0,5 \cdot \rho \cdot V^3 \cdot A} $$

Maximum power generated by a turbine is limited to $C_p = \frac{16}{27}$ according to the Betz limit

Tip Speed Ratio - rotor tip speed over wind speed

$$ \frac{\omega R}{U} $$

Capacity Factor - ratio of the actual output over a given period of thime to the maximum possible energy over the same period, practically, average power generated divided by the rated power of the turbine over a specific time

$$ CF = \frac{\text{average output}}{\text{peak output}} $$

Horizontal vs Vertical Wind Turbines

See more on Slide 30 onwards