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Seat No.: Enrolment
GUJARAT TECHNOLOGICAL UNIVERSITY
PDDC SEMESTER-IV EXAMINATION WINTER 2018
Subject Code:X41902 Date: 22/11/2018
Subject Name: Fluid Power Engineering
Time: 02:30 PM TO 05:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1

Show that in case of jet striking the flat plates mounted on wheel, the efficiency will be maximum when the tangential velocity of wheel is half of the jet.
07

What is the function of draft tube? State the type of draft tube and explain with a neat sketch of any one.
07
Q.2

Derive an expression for the optimum value of the intercooler pressure in a two stage reciprocating air compressor for perfect inter cooling condition.
07

A centrifugal air compressor draws air at a temperature of 27°C running at 14000 rpm has the following data:
1. Outer diameter of blade tip= 450 mm 2. Slip factor=0.90
3. Isentropic total head efficiency= 0.80
Assuming that the absolute velocities of air at inlet and outlet are same. Calculate
1. Temperature rise of air passing through compressor
2. Static pressure ratio
07
OR

A single stage, single acting Reciprocating compressor has clearance volume is of the swept volume. Air drawn at 0.9 bar and 270c. The delivery pressure is 7.5 bar. The atmospheric conditions are 1.013bar and 170 c. The index of compression or expansion is 1.3. Find 1. Indicated power when 3.5m3/min of free air delivered.
2. Volumetric efficiency and
3. Volumetric efficiency to free air delivered.
07
Q.3

Discuss any Characteristic curves of hydraulic turbine
07

A hydro-electric power plant developing 80MW brake power under the head 450m and at 450 rpm. Calculate total quantity of water required diameter of jet and no. of nozzle required. Assuming overall efficiency= pitch diameter of wheel to jet diameter ratio= 10, Co-efficient of velocity= 0.96 and speed ratio 0.45
07
OR
Q.3

Why governing of water turbine is required? Explain governing of any one hydraulic turbine with neat sketch
07

An inward flow reaction turbine produces 150kW while working under a head of 30 m. The discharge through the turbine is 720lit/sec and is radial outlet. The diameter at inlet and outlet are 60cm and 45cm respectively. Take the radial velocity at outlet as 4.8m/s, width of wheel constant and speed of runner is 600rpm. Calculate overall and hydraulic efficiencies and inlet angle of guide and runner blades.
07
Q.4

Give classification of Reciprocating pump. Draw neat sketch of single acting reciprocating pump.
07

A centrifugal pump runs at 550 rpm and discharges 7 m3/min against head of 11 m. It has impeller of 45 cm outer diameter and 20cm inner diameter. Vanes are set back at outlet angle of 400. The constant velocity flow is 2.5 m/s. Calculate:
1.The manometric efficiency 2.Vane angle at inlet.
07
OR
Q.4

Derive Darcy- Weisbach formula for calculating loss of head due to friction in a pipe
07
2

An oil of specific gravity 0.80 is flowing through a pipe of diameter 250 mm at the rate of 0.6 m3/sec . Find the head loss due to friction and power required to maintain the flow for a length of 450 meter. Take kinematic viscosity of an oil as 0.30 stokes.
07
Q.5

What do you mean by minor energy losses? Derive equation for the loss of head due to sudden enlargement in pipe.
07

Give detail classification of rotary compressor and explain any one with line sketch
07
OR
Q.5

Write short note on Jet pump.
07

Draw and explain Hydro-electric Power Plant with neat Sketch.
07