The preliminary design of a turbine for a new hydroelectric power scheme has under consideration a vertical-shaft Francis turbine with a hydraulic power output of 200 MW under an effective head of 110 m. For this particular design, a specific speed, Ωs = 0.9 (rad), is selected for optimum efficiency. At runner inlet the ratio of the absolute velocity to the spouting velocity is 0.77, the absolute flow angle is 68°, and the ratio of the blade speed to the spouting velocity is 0.6583. At runner outlet, the absolute flow is to be without swirl. Determine
a. the hydraulic efficiency of the rotor;
b. the rotational speed and diameter of the rotor;
c. the volume flow rate of water;
d. the axial length of the vanes at inlet.