1. A Francis turbine operates at its maximum efficiency point at no 0.94, %3D corresponding to a power specific speed of 0.9 rad. The effective head across the turbine is 160 m and the speed required for electrical generation is 750 rev/min. The runner tip speed is 0.7 times the spouting velocity, the absolute flow angle at runner entry is 72 deg from the radial direction and the absolute flow at runner exit is without swirl. Assuming there are no losses in the guide vanes and the mechanical efficiency is 100 percent, determine: (1) the turbine power and the volume flow rate; (2) the runner diameter; (3) the magnitude of the tangential component of the absolute velocity at runner inlet; (4) the axial length of the runner vanes at inlet.

1. A Francis turbine operates at its maximum efficiency point at no 0.94, %3D corresponding to a power specific speed of 0.9 rad. The effective head across the turbine is 160 m and the speed required for electrical generation is 750 rev/min. The runner tip speed is 0.7 times the spouting velocity, the absolute flow angle at runner entry is 72 deg from the radial direction and the absolute flow at runner exit is without swirl. Assuming there are no losses in the guide vanes and the mechanical efficiency is 100 percent, determine: (1) the turbine power and the volume flow rate; (2) the runner diameter; (3) the magnitude of the tangential component of the absolute velocity at runner inlet; (4) the axial length of the runner vanes at inlet.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.19P

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