In the inlet velocity triangle of a Kaplan turbine, α1 = 45o. The velocity of flow at inlet = 10 m/s. Find the whirl velocity of water at the inlet of Kaplan turbine?

Correct Answer: 10 m/s
In the inlet velocity triangle, tan (α1) = Vf1/ Vw1Since α1 = 45o, Vf1 = Vw1 = 10 m/s.