In: Physics
A 3-blade wind turbine with a diameter of 16 m spins at 35 rpm at a 5000 m elevation where the average wind speed is 30 km/hr. The atmospheric pressure and temperature at that location are 98 kPa and -10 oC, respectively. There is a rotating wake behind the turbine. Neglecting the frictional drag, calculate the maximum power coefficient and maximum power.
Power Co-efficient is given by the equation
where
means the conversion efficiency of the turbine, motor and the
electrical efficiency respectively(see the attatched
figure)
the typical values of
and
for the given wind speed are as given below
ηb = 0.397
ηm = 0.96
ηe = 0.94
where
and
means the output and input powers respectively.
where
is the density of the air,
is the area swept by the turbine and
is the velocity of the wind.
where
is the absolute pressure,
is the specific gas constant for dry air and
is the Absolute temperature.
from the given question,
.