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Reg No.: Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
FOURTH SEMESTER B.TECH DEGREE EXAMINATION, DECEMBER 2018

Course Code: ME206
Course Name: FLUID MACHINERY (ME)

Max. Marks: 100 Duration: 3 Hours
PART A
Answer any three questions. Each question carries 10 marks.

1 a) In ೩ Pelton wheel turbine, the runner of the turbine is provided with double hemi- 4
spherical cup shaped buckets instead of single curved blade. why?

b) A jet of 7.5cm diameter strikes a flat plate, normal of which is inclined at 45° to 6
the axis of the jet with a velocity of 25m/s. Find the normal force exerted on the
plate i) When the plate is stationery ii) When the plate is moving with a velocity of
15m/s in the direction of jet and away from the jet.

2 9) Explain advantages and disadvantages of a Pelton turbine? 3 9) Prove that the hydraulic
efficiency of a Pelton wheel turbine is maximum when 7 the jet velocity striking the runner
is twice the tangential velocity of the runner? 3 a) What is meant by specific speed of a
turbine? What is its significance? 4 b) With neat sketches, explain the working servo motor
mechanism of governing of a 6 pelton turbine.
4 a) Explain the theory of draft tube in reaction turbine. How is the turbine 5 performance
affected in the absence of draft tube?

b) A Kaplan turbine is designed to develop 9MW power while operating under a net 5
head of 7m. The speed ratio based on outer diameter and flow ratios are to be 2.09
and 0.68 respectively and the ratio of outer to hub diameter is 3. Assuming an
overall efficiency of 85%, find the speed and specific speed of the turbine.

PART B Answer any three questions. Each question carries
10 marks

5 a) Reciprocating pumps are called positive displacement pump why? 3 b) A
centrifugal pump lifts 2.5m*/min of water to a height of 20m through a pipe line 7
of 10cm diameter. The total length of the pipe line is 11 0൩. Assuming an overall
efficiency of 75% and an inlet loss of 0.3m, find the power required to drive the

pump. Take coefficient of friction f = 0.012

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