(a) A 1:10 scale model of Francis' turbine system has a diameter of 50 cm and works with 380 rpm to produce 70 kW. It is required to build a similar prototype with a specific speed of 350 and a hydraulic efficiency of 80 %. The guide vane deflects the water with an angle of 30° with the tangential direction with constant velocity of flow. The total energy loss between the turbine runner exit point and the tail race is one seventh of the kinetic energy at exit from the runner. Investigate the possibility of cavitation if the turbine delivers water to tailrace with a velocity of 0.4 m/s. Find the suitable height for the turbine to be placed above the tailrace and to work without cavitation. Take the atmospheric and vapor pressures as 1 bar and 0.04 bar respecti vely.

(a) A 1:10 scale model of Francis' turbine system has a diameter of 50 cm and works with 380 rpm to produce 70 kW. It is required to build a similar prototype with a specific speed of 350 and a hydraulic efficiency of 80 %. The guide vane deflects the water with an angle of 30° with the tangential direction with constant velocity of flow. The total energy loss between the turbine runner exit point and the tail race is one seventh of the kinetic energy at exit from the runner. Investigate the possibility of cavitation if the turbine delivers water to tailrace with a velocity of 0.4 m/s. Find the suitable height for the turbine to be placed above the tailrace and to work without cavitation. Take the atmospheric and vapor pressures as 1 bar and 0.04 bar respecti vely.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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