17.6.1. Coefficient of Lift (CL)

Try these first

1. 1.

   Define the coefficient of lift.

   Hint

   Think about what ratios we calculate in physics.

2. 2.

   What direction does the lift force act?

   Hint

   Consider how airplanes take off.

3. 3.

   What does the coefficient of lift (CL) measure?

   • Lift force relative to weight
   • Lift force relative to dynamic pressure and area
   • Lift force without any factors

   Hint

   Focus on what CL is designed to represent.

4. 4.

   True or False: A higher Reynolds number typically leads to a higher coefficient of lift.

   • True
   • False

   Hint

   Consider how different flow types interact with surfaces.

5. 5.

   A wind turbine with a blade length of 5 m generates a lift force of 2000 N at a wind speed of 15 m/s. Calculate the coefficient of lift if the air density is 1.225 kg/m³.

   Hint

   Calculate the area of the turbine blades first.

6. 6.

   Explain how changing the shape of a bicycle helmet influences the aerodynamics and thereby the lift and drag experienced by the rider.

   Hint

   Think about how shapes create turbulence.