How does the flow ratio (ψ) of a Francis turbine vary with available head (H)?

Related MCQs

• The velocity of the flow through the Kaplan turbine is 25 m/s. The available head of the turbine is 60 m. Find the flow ratio of the turbine (take g = 10 m/s2).
• A student performs an experiment with a Francis turbine. He accidently set the RPM of Francis turbine to 1400 rpm instead of 700 rpm. He reported the power to be 1 MW. His teacher asks him to perform the same experiment using the correct RPM. The student performs the same experiment again, but this time the erroneously doubled the flow velocity. What does the student report the power to be?
• The available head of a Francis Turbine is 100 m. Velocity of the flow at the runner inlet is 15 m/s. Find the flow ratio.
• The available head of a Francis Turbine is 120 m. The blade velocity is given 35 m/s. Find the speed ratio of the turbine.
• A Kaplan turbine requires a speed ratio of 2. The available head of the turbine is 5 m. What should be the blade velocity of the turbine such that a speed ratio of 2 is maintained (take g = 10 m/s2)?
• Which of the following efficiencies for Francis Turbine is defined as the ratio between the power available at the shaft of the turbine to the power produced by the runner?
• Volume flow rate of water in a Francis turbine runner is 25 m3/s. The flow velocity, whirl velocity and blade velocity are 11 m/s, 10 m/s and 5 m/s respectively, all values given at runner inlet. Find the power developed by the turbine.
• The flow rate of the water flow in a Francis turbine is increased by 50% keeping all the other parameters same. The work done by the turbine changes by?
• The volume flow rate into a Francis turbine is Q m3/s. 0.25Q m3/s volume of water do not flow over the runner blades. What is the mechanical efficiency of the turbine (in %)?
• The volumetric efficiency of a Francis turbine is given to be 90%. If the volume flow rate through the turbine is 25 m3/s. What is the flow rate of water over the runner blades (in m3/s)?