Answer to Question #305623 in Mechanical Engineering for ravi

Question

Define: i. Cut-in speed ii. Cut-out speed iii. Yaw control iv. Coefficient of performance of a wind mill

Answer 1

Cut-in speed:

The cut-in speed (typically between 6 and 9 mph) is when the blades start rotating and generating power

Cut-out speed:

The cut-out speed is the point at which the turbine must be shut down to avoid damage to the equipment. 

Yaw control, that is, the control to nose the helicopter fuselage left or right, is accomplished by means of the tail rotor (for a single rotor–tail rotor machine). A major function of the tail is, first, to counteract the torque of the main rotor.

Coefficient of performance of a wind mill

The coefficient of performance, CP, also called the power coefficient of a wind turbine, is defined as the ratio of the power captured by the rotor of the wind turbine, PR, divided by the total power available in the wind, P, just before it interacted with the rotor of the turbine.