Railways
NTPC (Technical Ability)
Instrument Mechanical
Question Bank
Instrument Mechanical
question_answer
The gross head available to a hydraulic power plant is 100 m. The utilized head in the runner of the hydraulic turbine is 72 m. If the hydraulic efficiency of the turbine is 90%, the pipe friction head is estimated to be:
A)20 m
B)18 m
C)16.2 m
D)1.8 m
Correct Answer:
B
Solution :
Frictional head lost, \[{{H}_{L}}={{\eta }_{hyd}}\times H-{{H}_{u}}=0.9\times 100-72=18\,m\]