The power available at the shaft of a Kaplan turbine is 0.75 MW. The volume flow rate of water in 15 m3/s, whirl velocity at inlet is 12 m/s and blade velocity is 5 m/s. Find the mechanical efficiency (in %)?

Correct Answer: 83.33
Mechanical efficiency of a Kaplan Turbine is given by ηm = shaft power / ρQVw1u1. Substituting the given values into this equation, we get mechanical efficiency = 83.33%.