2. Assume a 3-blade wind turbine with 30-m diameter, and 3-m hub diameter. The airfoil-shaped blades...

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2. Assume a 3-blade wind turbine with 30-m diameter, and 3-m hub diameter. The airfoil-shaped blades have lift coefficient of (C = 0.25 +0.0847a a < 12 (C = 1.27 a > 12 The turbine has its peak power coefficient at a tip speed ratio of 9, and has minimum drag to lift ratio at an angle of attack of 10 degrees. In two different cases of no wake rotation, and existing wake rotation, and for 20 station of the blade, calculate A) Pitch angle B) Cord length C) Twist angle D) Compare twist angle ang cord length distributions along the blade for two cases above. Note: For both cases, assume no losses in your calculation. For the case with the wake rotation, Assume: Cd=0 no tip loss For the case without wake rotation Assume: Cd=0 a=1/3 a =0 no tip loss 2. Assume a 3-blade wind turbine with 30-m diameter, and 3-m hub diameter. The airfoil-shaped blades have lift coefficient of (C = 0.25 +0.0847a a < 12 (C = 1.27 a > 12 The turbine has its peak power coefficient at a tip speed ratio of 9, and has minimum drag to lift ratio at an angle of attack of 10 degrees. In two different cases of no wake rotation, and existing wake rotation, and for 20 station of the blade, calculate A) Pitch angle B) Cord length C) Twist angle D) Compare twist angle ang cord length distributions along the blade for two cases above. Note: For both cases, assume no losses in your calculation. For the case with the wake rotation, Assume: Cd=0 no tip loss For the case without wake rotation Assume: Cd=0 a=1/3 a =0 no tip loss