The first stage of a turbine is a two-row velocity compounded wheel. Steam at 40 barand 400 C is expanded in the nozzles to 15 bar, and has a velocity at discharge of700 m/s. The inlet velocity to the stage is negligible. The relevant exit angles are: nozzle18°; first row blades 21°; fixed blades 26.5"; second row blades 35°. Take the bladevelocity coefficient for all blades as 0.9. The mean diameter of the blading is 750 mmand the turbine shaft speed is 3000 rev/min. Draw the velocity diagram for this wheland calculate:(i) the diagram efficiency;(ii) the stage efficiency.(70.8%; 67.4%)

INTRODUCTION : Turbines are the prime movers in which the heat energy of the steam is converted…

The first stage of a turbi and 400 "C is expanded 700 m/s. The inlet velocit 18°; first row blades 21 velocity coefficient for al and the turbine shaft spe and calculate: (i) the diagram efficience (ii) the stage efficiency.

The first stage of a turbi and 400 "C is expanded 700 m/s. The inlet velocit 18°; first row blades 21 velocity coefficient for al and the turbine shaft spe and calculate: (i) the diagram efficience (ii) the stage efficiency.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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