Correct Answer : Option (C) : Constant velocity
Explanation : Area of spiral structure gradually decreases because as discharge decreases correspondingly area also decreases. So, runner will rotate with constant velocity.
Correct Answer : 90.91
Explanation : The definition of Hydraulic efficiency in a Kaplan turbine states that it is the ratio between the Runner power to the shaft power. If input water power is 1.10 times the runner power, the runner power is 1/1.10 = 0.90909 Times the water power. Hence, hydraulic efficiency = 90.91%.
Correct Answer : Hydraulic efficiency
Explanation : The definition of Hydraulic efficiency in a Kaplan turbine states that it is the ratio between the Runner power to the shaft power. Hence, the correct option is Hydraulic efficiency.
Correct Answer : Kaplan turbine
Explanation : As the head for Kaplan turbine is low, the discharge of water through the turbine is high and hence, blade resistance should be low. That’s why Kaplan turbine will have the lowest number of blades.
