Power developed by Francis turbine are calculated for a certain set of conditions. Now, the inlet whirl velocity is doubled, the blade velocity at inlet is doubled and the flow velocity is quartered. The power developed:

Correct Answer: Is same as the original value
The power developed by a Francis Turbine is given by P = ρAV (Vw1.u1). Hence, if inlet whirl velocity is doubled, the blade velocity at inlet is doubled and the flow velocity is quartered, then the power developed will remain the same as its original value.