Wi nd Po w er 3

What is the approximate theoretical limit for the maximum efficiency of wind turbines?

• 0.74
• 0.67
• 0.59
• 0.81
• 0.51

Where is the airfoil the thickest?

• at the tip
• midway
• at the root
• The thickness must be the same throughout

What is the relationship between wind speed and power generated?

• Inverse
• Direct
• Direct Squared
• Direct Cubed
• Inverse Squared

What are ideal locations for wind towers?

• inland
• coastal regions
• hills
• Both A & B
• Both B & C

In early publications, the efficiency curves of this design, and the American Multiblade design were switched inadvertently, making it appear as though the following design was less favorable to study.

• Dutch four arms wheel
• High Speed Two Blade Design
• Darrius Rotor
• Savonius Rotor
• Teeter Hinged Rotor

By which mechanisms can power loss be reduced in wind turbines?

• by decreasing the height
• by using more than 3 blades and increasing the speed
• by utilizing a pitch system
• by switching to a VAWT design
• By incorporating a step down transformer into the substations

At the tip of a rotor blade, describe the direction of airflow.

• Upper side of the airfoil profile to lower side.
• Lower side of airfoil profile to upper side
• From the tip of the rotor blade towards the root

State the directionality of the lift force on a turbine blade relative to the direction of wind flow.

• Parallel
• Perpendicular
• There is not enough information to answer this question

What is the name of the opposing force on a turbine blade?

• Drag
• Lift
• Thrust
• Resistance
• none of the above

In which type of design can turbine blades have no twist?

• Horizontal axis wind turbines
• Vertical axis wind turbines