A Francis turbine is to be designed to develop 3700 kW of power under a head of 70 m while running at a speed of 600 rpm. Following are some pertinent data of the turbine:
• Ratio of width of runner to outer diameter of the runner = 0.1
• Ratio of outer diameter to inner diameter of the runner = 0.5
• Flow ratio = 0.25
• Hydraulic efficiency = 95%
• Mechanical efficiency = 80%
• Circumferential area occupied by thickness of vanes = 10%
Assuming constant flow velocity, calculate (a) guide vane angle, (b) runner blade angle at inlet, and (c) blade angle at the outlet.