- #1
russde
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I have a Thermo I problem:
Given: 80m diameter wind turbine rotating at 20rpm under steady wind conditions at an average wind velocity of 30kph. The eff of the system is 35%.
Need: Power generated
Assumptions (made by me):delta PE ~0; mass=constant; operating at Steady Sate; T~constant
Now, since the eff is = W/Energy and E=delta U +deltaKE +deltaPE this should reduce to:
Eff=W/deltaKE with my assumptions
deltaKE=1/2 m (V2^2 - V1^2)
I know that V2 should be larger than V1 and p2 should be less than p1 but this is where I get stuck, finding V2.
With T~constant specific enthalpy is 0, and entropy will also be 0...
right?
How about a hint to get me on the right path?
Thanks,
R
Given: 80m diameter wind turbine rotating at 20rpm under steady wind conditions at an average wind velocity of 30kph. The eff of the system is 35%.
Need: Power generated
Assumptions (made by me):delta PE ~0; mass=constant; operating at Steady Sate; T~constant
Now, since the eff is = W/Energy and E=delta U +deltaKE +deltaPE this should reduce to:
Eff=W/deltaKE with my assumptions
deltaKE=1/2 m (V2^2 - V1^2)
I know that V2 should be larger than V1 and p2 should be less than p1 but this is where I get stuck, finding V2.
With T~constant specific enthalpy is 0, and entropy will also be 0...
right?
How about a hint to get me on the right path?
Thanks,
R