1. A 75 m high wind tower with a 50 m rotor diameter has been constructed in a region that follows the 1/7th rule for the coefficient of shear friction. The blades that have been selected for the turbine can reliably operate over a prolonged period of time if the maximum power ratio experienced during each blade rotation does not exceed 1.4. Are these blades suitable for this turbine? Justify your answer with numerical evidence (a calculation). 2. A 2.1 MW wind turbine system has a rotor diameter of 78 m and a rated speed of 12 m/s. What is the efficiency of the entire wind turbine system? Assume a density of 1.225 kg/m3 .

1. A 75 m high wind tower with a 50 m rotor diameter has been constructed in a region that follows the 1/7th rule for the coefficient of shear friction. The blades that have been selected for the turbine can reliably operate over a prolonged period of time if the maximum power ratio experienced during each blade rotation does not exceed 1.4. Are these blades suitable for this turbine? Justify your answer with numerical evidence (a calculation). 2. A 2.1 MW wind turbine system has a rotor diameter of 78 m and a rated speed of 12 m/s. What is the efficiency of the entire wind turbine system? Assume a density of 1.225 kg/m3 .

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.32P

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