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Q5. The first stage of an impulse turbine is a two rows Curtis wheel. Steam leaves the nozzles at a velocity of 550 m/s and an angle of 17 o to the plane of rotation. The blade speed is 125 m/s.

The first and second row of moving blades have symmetrical blading and the fixed blade outlet angle is 26°.

The blades have a velocity coefficient of 0.9.

(a) Draw The steam velocity vector diagram to a scale of 1 mm = 5 m/s (5)

(b) Determine EACH of the following:

(i) The moving blade inlet and outlet angles; (3)

(ii) The fixed blade inlet angle; (2)

(iii) The angle and absolute velocity of the steam leaving the stage; (2)

(iv) The diagram efficiency. (4)