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(DME 311)

B.Tech. DEGREE EXAMINATION, MAY - 2015

(Examination at the end of Third Year)

MECHANICAL ENGINEERING

Paper - I : Operation Research

Time : 3 Hours Maximum Marks : 75

Answer question No.1 compulsory (15)

Answer ONE question from each unit (4 × 15 = 60)

1) Write brief note on :

a) Scope of operation research.

b) Slack and surplus variable

c) Vogel‟s approximation for transportation problem.

d) Characteristics of queing system.

e) Two person zero – sum game.

UNIT – I

2) Solve by simplex method

Maximize Z = 5x1 – 4x2 + 3x3

Subject to 2x1 + x2 – 6x3 = 20

6x1 + 5x2 + 10x3 < 76

8x1 – 3x2 + 6x3 50

x1, x2, x3 0

OR

3) a) Write a short note on degeneracy.

b) Using dual simplex method solve the following problem

Minimize Z = 2x1 + 2x2 + 4x3

Subject to 2x1 + 3x2 + 5x3 2

3x1 + x2 + 7x3 3

x1 + 4x2 + 6x3 5

x1, x2, x3, x4 0

UNIT - II

4) a) Problem solve the following transportation problem.

Destination

A B C

I 21 16 25 13 11

Source II 17 18 14 23 13 Availability

III 33 27 18 41 19

6 10 12 15 43

Requirement

OR

b) Given the matrix of set-up cost show how to sequence the production so as to minimize the

set up cost per cycle.

A1 A2 A3 A4 A5

A1 2 5 7 1

From A2 6 3 8 2

A3 8 7 4 7

A4 12 4 6 5

A5 1 3 2 8

UNIT - III

5) Derive the economic lot size formula for the optimum production quantity q per cycle of a single

product so as to minimize the total average cost per unit time.

OR

6) A man is engaged in buying and selling identical items. He operates from a ware house that can

hold 500 items each month he can sell any quantity that he chooses upto the stock at the beginning

of the month. Each month he can buy as much as he wishes for delivery at the end of the month so

long as his stock does not exceed 500 items. For the four months. He has the following error – free

forecasts of cost sales prices.

Month i 1 2 3 4

Cost ci 27 24 26 28

Sale price pi 28 25 25 27

UNIT - IV

7) The following table list the Jobs of network with their estimates.

Duration

Job Optimistic to Most likely tm Pessimistic

1-2

1-6

2-3

2-4

3-5

4-5

6-7

5-8

7-8

3

2

6

2

5

3

3

1

4

6

5

12

5

11

6

9

4

19

15

14

30

8

17

15

27

7

28

a) Draw the project network.

b) Calculate the length and variance of the critical path.

c) What is the approximate probability that the Jobs on critical path will be completed in 41

days.

OR

8) Explain the forward pass and back ward pass competations for critical path method.

(DME 312)




Paper - II : Design of Machine Elements




1) a) State commonly used materials for rivets.

b) Define the efficiency of compound screw.

c) What are the applications of cotter joint?

d) Explain Self locking screws.

e) What are the various factors influence the endurance limit of a material?

f) What is reinforcement in weld? What are advantage of it?

g) What is fatigue stress concentration factor?

UNIT – I

2) a) Discuss about phases of design.

b) Explain :

i) Thermal stress

ii) Hoop stress

OR

3) a) Explain the following theories of failure.

i) Maximum principal (normal) stress theory

ii) Maximum shear stress theory.

b) Explain the terms reliability, maintainability and availability in the design of mechanical

component.

UNIT - II

4) A square threaded transmission screw used in a screw jack has a root diameter of 80mm and a lead

of 12mm. It is double thread and is designed to lift a load of 120KN. The coefficient of friction is

0.15. Determine the following.

a) Pitch of the screw

b) Mean radius of thread

c) Efficiency of screw

d) Unit compressive stress in the screw.

e) Bearing pressure on the projected area of the threads in contact.

f) Is the screw self locking.

OR

5) a) Explain the Goodman method for combination of stress.

b) A 5 cm diameter shaft is made from carbon steel having ultimate tensile strength of

6300Kgf/cm2. It is subjected to a torque which fluctuates between 20000Kgf-cm to 8000Kgf-

cm. Using Soder berg method, calculate the factor of safety. Assume suitable values for any

data needed.

UNIT - III

6) Design a double riveted butt joint with two cover plates for the longitudinal seam of a boiler shell

of 800mm diameter. The maximum steam pressure is 1.2MPa. The allowable stresses are T =

30MPa, 1 = 37MPa, c = 55MPa. The efficiency of the joint is 70%. The corrosion allowance is

1mm.

OR

7) A bracket carrying a load of 15kN is to be welded as shown in figure. Find the size of weld

required if the allowable shear stress is not to exceed 80MPa.

UNIT – IV

8) Explain the following:

a) Design of socket and spigot cotter joint.

b) Distinguish among through bolt. Carriage bolt, tap bolt stud and set screw.

OR

9) Design a knuckle joint to transmit 150kN. The design stresses may be taken as 75MPa, in tension,

60MPa in shear and 150MPa in compression.

(DME 313)




Paper - III : Machine Dynamics




1) Explain the following :

a) ISOCHRONISM.

b) Gyroscopic Torque.

c) PRONY Brake Dynamometer.

d) Dynamic Balancing.

e) Stability of a Governor.

UNIT – I

2) In a vertical double – acting steam engine, the connecting rod is 4.5 times the crank. The weight of

the reciprocating parts is 120 kg and the stroke of the piston is 440 mm. The engine runs at 250

rpm. If the net load on the piston due to steam pressure is 25kN when the crank has turned through

an angle of 120º from the top dead centre, determine the

i) thrust in the connecting rod.

ii) pressure on slide bars.

iii) tangential force on the crank pin.

iv) thrust on the bearings.

v) turning moment on the crankshaft.

OR

3) The length of a connecting rod of a gas engine is 500 mm and its centre of gravity lies at 165 mm

from the crank pin centre. The rod has a mass of 80 kg and a radius of gyration of 182 mm about

an axis through the centre of mass. The stroke of piston is 225 mm and the crank speed is 300 rpm.

Determine the inertia force on the crank shaft when the crank has turned a) 30º and b) 135º from

the inner dead centre.

UNIT - II

4) Discuss in brief the following :

a) Balancing of Locomotives.

b) Hammer blow.

c) Swaying couple.

d) Slider – Crank mechanism.

e) Dynamic Balancing.

OR

5) Derive an expression for secondary force while balancing V-engines. Explain with a neat sketch.

UNIT - III

6) a) Derive an expression for power using Belt Transmission Dynamometer with neat sketch.

b) Following data refers to a rope brake dynamometer.

Brake drum radius = 120 cm

Radius of rope (r1) = 10 cm

Dead laod (w) = 2500 N

Spring balance (s) = 400 N

Speed N = 300 RPM

Determine brake power, indicated power and frictional power if mechanical efficiency is

80%.

OR

7) a) Explain with neat sketches, the Gyroscopic effect on Naval ships.

b) A motor cycle and its rider together have a mass of 200 kg and their centre of gravity is 0.6

m above the ground level when the motor cycle is upright. Each road wheel is 0.6m diameter

and has a moment of inertia 1kgm2. The rotating parts of the engine have a moment of inertia

0.17kgm2. The engine rotates at 5.5 times the speed of the road wheels and in the same sense.

Determine the angle of heel necessary when the motor cycle is rounding a curve of 30m

radius at a speed of 55KPMH.

UNIT - IV

8) Each arm of a porter governor is 200mm long and is pivoted on the axis of the governor. The radii

of rotation of the balls at the minimum and the maximum speeds are 120mm and 160mm

respectively. The mass of the sleeve is 24kg and each ball is 4kg. Find the range of speed of the

governor. Also determine the range of speed if the friction at the sleeve is 18N.

OR

9) In a spring loaded governor of Hartnell type the lengths of the horizontal and the vertical arms of

the bell-crank lever are 40mm and 80mm respectively. The mass of each ball is 1.2kg. The

extreme radii of rotation of the balls are 70mm and 105 mm. The distance of the fulcrum of each

bell-crank lever is 75mm from the axis of rotation of the governor. The minimum equilibrium

speed is 420 rpm and the maximum equilibrium speed is 4% higher than this. Neglecting obliquity

of the arms,

Determine

a) The spring stiffness.

b) Initial compression and

c) Equilibrium speed corresponding to radius of rotation of 95mm.

(DME 314)




Paper - IV : Hydraulic Machines




1) a) Find the force exerted by a jet of water of diameter 75 mm on a stationary flat plate, when

the jet strikes the plate normally with velocity of 20 m/s.

b) Define the terms : Hydraulic Machines, Turbines & Pumps.

c) Define the terms : Suction head, delivery head & static head.

d) Define slip, percentage slip & negative slip of a reciprocating pump.

e) What is meant by geometric, kinematic & dynamic similarities?

UNIT - I

2) a) Obtain an expression for the force exerted by a jet of water on a fixed vertical plate in the

direction of the jet.

b) A jet of water of diameter 50 mm having a velocity of 20 m/s strikes a curved vane which is

moving with a velocity of 10 m/s in the direction of the jet. The jet leaves the vane at an

angle of 60º to the direction of motion of vane at outlet. Determine. (5 + 10 =15)

i) The force exerted by the jet on the vane in the direction of motion.

ii) Work done per second by the jet.

OR

3) A jet of water of diameter 100 mm strikes a curved plate at its centre with a velocity of 15m/s. The

curved plate is moving with a velocity of 7m/s in the direction of the jet. The jet is deflected

through an angle of 150º. Assuming the plate smooth find : (3 × 5 =15)

a) Force exerted on the plate in the direction of the jet.

b) Power of the jet & c) Efficiency.

UNIT - II

4) A Peltan wheel is revolving at a speed of 200 r.p.m. and develops 5886 kW S.P. when working

under a head of 200 m with an overall efficiency of 80%. Determine unit speed, unit discharge &

unit power. The speed ratio for the turbine is given as 0.48. Find the speed, discharge & power

when this turbine is working under a head of 150m. (15)

OR

5) A Francis turbine with an overall efficiency of 70% is required to produce 147.15 kW. It is

working under a head of 8m. The peripheral velocity = and the radial velocity of flow

at inlet is . The wheel runs at 200 r.p.m. and the hydraulic losses in the turbine are 20%

of the available energy. Assume radial discharge, determine (3 + 4 + 4 + 4 = 15)

i) The guide blade angle.

ii) The wheel vane angle at inlet.

iii) Diameter of the wheel at inlet, &

iv) Width of wheel at inlet.

UNIT - III

6) A single – acting reciprocating pump has a plunger of 10 cm diameter and a stroke of length 200

mm. The centre of the pump is 4m above the water level in the sump & 14 m below the level of

water in a tank to which water is delivered by the pump. The diameter and length of suction pipe

are 40 mm and 6 m while of the delivery pipe are 30 mm & 18 m respectively. Determine the

maximum speed at which the pump may be run without separation. If separation occurs at 7.848

N/cm2 below the atmospheric pressure. Take atmospheric pressure head is 10.3 m of water.

(7½ + 7½ = 15) OR

7) a) With the help of a neat sketch explain the various component parts of a centrifugal pump. (10)

b) How will you obtain an expression for the minimum speed for starting a centrifugal pump? (5)

UNIT - IV

8) Derive on the basis of dimensional analysis suitable parameter to represent the thrust developed by

a probelles. Assume that the thrust P depends upon the angular velocity „ ‟ speed of advance „V‟

diameter „D‟ dynamic viscosity „ ‟ mass density and elasticity of the fluid medium which can be

denoted by the speed of the sound in the medium C. (15)

OR

9) Assuming that the viscous force F exerted by a fluid on a sphere of diameter D depends on the

viscosity mass density of fluid P, & the velocity of sphere „V‟ obtain an expression for the

viscous force. (15)

(DME 315)

B. Tech. DEGREE EXAMINATION, MAY - 2015

(Examination at the End of Third Year)


Paper - V : I.C. Engines and Gas Turbines


Answer question No. 1 is compulsory (15)

Answer ONE question from each unit (4 x 15 = 60)

1) a) Differentiate between a flywheel and a governor.

b) Define the terms pre-ignition and detonation.

c) What is meant by ignition delay?

d) What are causes of knock in C.I. Engines?

e) Define the terms Bore, Stroke, Swept volume, compression ratio and clearance volume.

f) Write a short note on fuels used for gas turbines.

g) State the fundamental differences between the jet propulsion and Rocket propulsion.

Unit - I

2) Explain classification of I.C. Engines. Draw the value timing diagram for 4-stroke engine and

briefly explain the working principle of it.

OR

3) a) Explain the working principle of simple carburettor with a neat sketch.

b) Comparision between a Flywheel and a Governor.

Unit – II

4) A 2-cylinder C.I engine with a compression ratio 14 : 1 and cylinder dimensions of 200 mm × 250

mm works on two stroke cycle and consumes 14 kg/h of fuel while running at 300 r.p.m. The

relative and mechanical efficiencies of engine are 65% and 76% respectively. The fuel injection is

effected upto 5% of stroke. If the calorific value of the fuel used is given as 41800 kJ/kg. Calculate

the mean effective pressure developed?

OR

5) What is combustion of fuels? Explain in detail combustion analysis, And types.

Unit – III

6) a) What is combustion process? In S.I Engines and C.I Engines?

b) Write a short notes on octane number and cetane number.

OR

7) An axial flow compressor with an overall Isentropic efficiency of 85% draws air at 20oC and

compress if in the pressure ratio 4 :1, The mean blade speed and flow velocity are constant

throughout the compressor. Assuming 50% reaction blading and taking blade velocity as 180 m/s

and work input factor as 0.82 calculate :

i) Flow velocity.

ii) Number of stages.

Unit – IV

8) a) Draw the schematic layout of gas turbine cycle with regenerator, reheating and intercooler?

Explain salient features.

b) What do you mean by jet propulsion?

OR

9) In a jet propulsion unit air is drawn into the Rotary compressor at 15ºC and 1.01 bar and delivered

at 4.04 bar. The isentropic efficiency of compression is 82% and the compression is uncooled.

After delivery the air is heated at constant pressure until the temperature reaches 750ºC. The air

then passes through a turbine unit which drives the compressor only and has an isentropic

efficiency of 78% before passing through the nozzle and expanding to atmospheric pressure of

1.01 bar with an efficiency of 88%. Neglecting any mass increase due to the weight of the fuel,

determine :

i) The power required to drive the compressor.

ii) The air-fuel ratio if the fuel has a calorific value of 42000 KJ-Kg.

iii) The pressure of the gases leaving the turbine.

iv) The thrust per kg of air per-second.

(DME 316)

B. Tech. DEGREE EXAMINATION, MAY - 2015



Paper - VI : Metal Cutting & Machine Tools


Answer question No. 1 is compulsory (15)

Answer ONE question from each unit (4 x 15 = 60)

1) Write a short notes on the following:

a) What are the basic elements for machining operations? Explain any two.

b) Explain about all geared head stock.

c) Explain about cross-rail in shapes.

d) What are the work holding devices in milling machine?

e) What are the Drilling tools? Explain one.

UNIT - I

2) Explain briefly with neat diagrams of any six Lathe accessories.

OR

3) a) Explain Thread Cutting by using Lathe.

b) Explain Machining Parameters in Lathe.

UNIT – II

4) What are the types of Drilling Machines? Discuss briefly with neat diagram of Radial drilling

machine.

OR

5) a) Explain the factors to be kept in mind in selecting a grinding wheel?

b) Identify standard marking system gives below on grinding wheel

30 – A – 36 – H – 6 – V – G

UNIT – III

6) a) Explain with sketch of Nomenclature of a plain milling cutter.

b) Explain briefly about Methods of Milling.

OR

7) a) Describe the construction and working of a “Column and Knee” type milling machine with

line diagram.

b) What are the Milling operations? Explain

UNIT – IV

8) a) Describe Tool Geometry of Single Point Cutting tool.

b) In orthogonal cutting of a mild steel component, if the rake angle of tool is 10º and shear

angle is 30º, find the chip thickness ratio.

OR

9) a) What are the factors influencing in tool life? Explain

b) Determine the cutting speed and machining per cut when the work having 35mm diameter is

rotated at 200 rpm. The feed given is 0.2 mm/rev and length of cutting is 60 mm.

(DME 321)




Paper - I : Operations Management


Answer question No. 1 compulsory (15)

Answer One question from each unit (4 × 15 = 60)

1) Write a brief note on the following :

a) Mass and flow production

b) TQM

c) Forecasting

d) XYZ Analysis

e) Job order production

UNIT – I

2) Briefly explain EOQ models.

OR

3) Explain Master scheduling methods.

UNIT – II

4) a) Enumerate Aggregate planning methods.

b) Explain different ranges of plan.

OR

5) a) Explain different planning models.

b) Discuss in brief functions of Materials Management.

UNIT – III

6) Explain in detail about MRP and its importance.

OR

7) Explain in detail about reliability of a system.

UNIT - IV

8) Explain in brief the following :

a) Purpose & Types of inventories.

b) Safety stock

c) CRP.

OR

9) Explain various charts used for quality control.

(DME 322)


(Examination at the End of Third Year)


Paper - II : Design of Transmission Elements


Answer question No.1 compulsorily (15)


1) a) What is hydrostatic lubrication?

b) In a worm gear only wheel is designed. Why?

c) Derive an expression for face width of helical gears.

d) Explain the various materials used for the belts.

e) Advantages of gear drives.

f) Function of a key.

g) What is crowing of belt pulley?

UNIT - I

2) A flexible coupling is used to transmit 15 kW power at 100 rpm. There are 6 pins and their pitch

circle diameter is 200 mm. The length of pin in contact with the left hand flange, the gap between

the two flanges and the length of bush in contact with the right hand flange are 23, 5 & 35mm

respectively. The permissible shear and bending stresses in the pin are 35 and 152 N/mm2

respectively. The permissible pressure for the rubber brush is 1N/mm2. Calculate

a) Pin diameter by shear consideration.

b) Pin diameter by bending consideration.

c) Outer diameter of the rubber brush.

OR

3) a) Explain the effect of keyways.

b) Design the rectangular key for a shaft of 50mm diameter. The shearing and crushing stresses

for the key material are 42 MPa and 70MPa respectively.

UNIT - II

4) Design a journal bearing for the following data :

Journal diameter = 70 mm

Journal speed = 450 rpm

Clearance = 0.0025 mm/mm

Viscosity of the oil = 10 centipoise at 75°C

Ambient temperature = 27°C

Specific gravity of oil = 0.9

OR

5) a) Discuss selection of parameters for Journal bearing design.

b) Why are ball and roller bearings described as anti-friction bearings.

UNIT - III

6) a) Derive an expression for centrifugal tension for belt.

b) A v-belt drive is required for a 15 kW, 1440 rpm electric motor. Which drives a centrifugal

pump running at 360 rpm for a service of 24 hrs per day. From space considerations the

centre distance should be approximately 1m. Determine

i) Belt specifications.

ii) Number of belts.

iii) Pulley diameters.

OR

7) Design a chain drive to actuate a compressor from 15 kW electric motor running at 1000 r.p.m,

the compressor speed being 350 r.p.m. The minimum centre distance is 500 mm. The compressor

operates 16 hours per day. The chain tension may be adjusted by shifting the motor on slides.

UNIT - IV

8) a) Explain desirable properties of a gear material.

b) A pair of spur gears with centre distance of 495 mm is used for a speed reduction of 4.5:1.

The module is 6mm. Calculate the number of teeth on the pinion and the gear.

OR

9) A cast iron helical gear with 30° helix angle has to transmit 20 kW at 1200 rpm. The safe static

stress for cost iron is 55 MPa. The width of face is 3.5 times circular pitch. If the gear has 24 teeth

determine the following for 20° full depth teeth.

a) Module.

b) Pitch diameter.

c) Width of face.

d) End thrust.

Assume lubrication factor = 1.15.

(DME 323)




Paper - III : Mechanical Vibrations


Answer question No.1 is compulsory (15)


1) a) What is meant by damping?

b) What is the equivalent stiffness of spring?

c) Discuss dynamic magnifier.

d) Explain about transmissibility.

e) What are the eigen values and eigen vectors?

UNIT - I

2) a) Explain different types of free vibrations.

b) How can we obtain the frequency, phase and amplitude of a harmonic motion from the

corresponding rotating factor.

OR

3) Determine the natural frequency of the simple pendulum of length L, mass m, if the mass of rod is

a) negligible

b) not negligible

UNIT - II

4) a) Explain logarithemic decrement.

b) Explain about structural damping and Interfacial damping.

OR

5) A coil of spring stiffness 4 N/mm supports vertically a mass of 20kg at the free end. The motion is

resisted by the oil dash pot. It is found that the amplitude at the begining of the fourth cycle is 0.8

times the amplitude of the previous vibration. Determine the damping force per unit velocity. Also

find the ratio of the frequency of damped and undamped vibrations.

UNIT - III

6) a) Determine the equivalent viscous damping from frequency response curve.

b) Discuss about the energy dissipated by damping.

OR

7) a) Explain Combined Rectilinear and angular modes of vibration.

b) Explain about viscous damping.

UNIT - IV

8) Determine the Natural frequency of the free longitudinal vibration using equilibrium method.

OR

9) A shaft of 40mm diameter and 2.5m long has a mass of 15kg per meter length. It is simply

supported at the ends and carries three masses 90kg, 140kg, and 60kg at 0.8m, 1.5m and 2m

respectively from the left support. Taking modulus of elasticity as 200 GPa. Find the frequency of

the Transverse vibration.

(DME 324)




Paper - IV : Basic Electronics and Microprocessors




1) a) Draw the circuit diagram of a Diode connected in forward bias.

b) Draw the output characteristics of Transistor.

c) What is meant by feed back?

d) Draw the symbols of JFET, MOSFET.

e) Convert (7F)16 to Decimal and Octal?

f) Write Demorgans Theorems.

g) Realize a three input NAND gate using basic gates.

h) Write Flags in 8085 Microprocessor?

i) What is Microprocessor?

UNIT - I

2) a) Discuss PN diode V-I characteristics with neat sketch.

b) Explain about formation of PN junction.

OR

3) a) With circuit and necessary wave forms explain the operation of HWR.

b) Explain the comparison between BJT and FET.

UNIT - II

4) a) Discuss the electrical characteristics of an OP-amp in details.

b) Compare and contrast an ideal OP-amp and practical OP-amp.

OR

5) a) Draw and explain colpits oscillators.

b) Discuss about condition for oscillations.

UNIT - III

6) a) Express the following function in sum of min terms and product of max terms

F(A,B,C,D)=B‟D+A‟D+BD.

b) Realize half adder using 2-i/p NAND gates.

OR

7) a) Realize an SR latch using.

i) NOR gates ii) NAND gates

b) Convert D-Flip Flop to T-Flip Flop.

UNIT - IV

8) a) Draw the internal architecture of 8085 and explain.

b) List the features of 8085 Microprocessor.

OR

9) a) Explain Instruction set of 8085.

b) Write a program to add N-8-bit numbers.

(DME 325)




Paper - V : Heat Transfer


Answer question No.1 is compulsory (15)

Answer any ONE question from each unit (4 × 15 = 60)

1) a) What is a thermal Resistance?

b) State Fourier‟s law of heat conduction.

c) Define temperature field and temperature radient.

d) What is the difference between critical radius of insulation and critical thickness of

insulation.

e) What is Biot number and Fourier number?

f) Define efficiency and effectiveness of fin.

g) What is the governing law for the radiation?

UNIT - I

2) a) Explain the different modes of heat transfer along with their governing laws.

b) Explain the electrical analogy of heat transfer. Illustrate the concept of electrical analogy

considering a multilayer composite wall.

OR

3) a) Define heat flux and thermal diffusivity and explain it‟s importance in conduction mode of

heat transfer.

b) A plane brick wall 25cm thick is faced with 5cm thick concrete layer. If the temperature of

the exposed brick face is 70°C and that of the concrete is 25°C, find out heat lost per hour

through a wall of 15m × 10m. Also determine the inter face temperature. Thermal

conductivity of the brick and concrete are 0.7 W/m°K and 0.95 w/m°K respectively.

UNIT - II

4) a) What is lumped mass model? Derive the equation for the temperature of a lumped body for

the specified transient condition.

b) A thick bronze plate ( = 0.86 × 10–5

m2/s and k = 26 W/m°K) is initially at a uniform

temperature of 250°C suddenly the surface is exposed to a coolant at 25°C Assuming h = 150

w/m°K. Determine the temperature at 5 cm from the surface after 10min of exposure.

OR

5) a) Explain Hyeho dynamic and thermal boundary layer with reference to flow over heated plate.

b) Water at 20°C is to be heated by passing it through the tube. Surface of tube is maintained at

90°C. The diameter of tube is 4cm while it‟s length is 9m. Find the mass flow rate so that

exist temperature of water will be 60°C. The properties of water are

= 995 kg/m3, Cp = 4.175 kJ/kg°K, K = 0.64 w/m°K,

V = 0.62 × 10–6

m2/s, = 4.25 × 10

–3 K

–1

UNIT - III

6) a) Explain with neat sketch development of boundary layer on hot and cold vertical plate

subjected to Natural convection.

b) Estimate heat transfer from a 40W incandescent bulb at 127°C to 27°C quiescent air

approximate the bulb as a 50 mm diameter sphere. What percentage of power is lost by free

convection.

OR

7) a) Define heat exchanger effectiveness and explain it‟s significance.

b) In a counter flow double pipe heat exchanger water is heated from 40°C to 80°C with oil

entering at 105°C and leaving at 70°C taking the overall heat transfer coefficient as 300

w/m2K and the water flow rate as 0.1 kg/s. Calculate the heat exchanger area.

UNIT - IV

8) a) Describe the phenomenon of radiation from real surfaces.

b) Two very large parallel planes with emissivities 0.3 and 0.8 exchanges radioactive energy.

Determine the percentage reduction in radioactive energy transfer when a polished

aluminium radiation shield (E = 0.04) is placed between them.

OR

9) Explain the following laws relevant to radiation heat transfer

a) Kirchhoff‟s law

b) Wien‟s displacement law

c) Planck‟s law

d) Lam bert law

(DME 326)




Paper - VI : Engineering Metrology




1) a) What is a comparator? Classify. (2)

b) Explain the principle of ring gauges. (2)

c) What is microscopic inspection? (2)

d) Explain locating pins. (2)

e) Explain the principle of calibration. (2)

f) Use of slip gauges. (2)

g) Write advantages of CMM. (2)

h) Define precision. (1)

UNIT - I

2) a) Write the differences between hole based system and shaft based system. (7)

b) Explain with the help of diagrams the measurement of angle using the sine bar and slip

gauges. (8)

OR

3) a) Explain the term Selective Assembly. (5)

b) Define terms : tolerance, allowance and limits. (6)

c) Explain Taylor‟s principle of limit gauges. (4)

UNIT - II

4) a) What are the steps involved in designing Jigs and fixtures. (8)

b) Briefly discuss the principle and operation of bevel gear generating machine with neat

sketch. (7)

OR

5) a) With neat sketch explain about working of various clamping devices. (8)

b) Explain the principle of inspecting involute profile of gear tooth. (7)

UNIT - III

6) a) Name the various types of pitch errors found in screw? State their causes? (7)

b) Explain any pneumatic comparator, list out its merits and applications. (8)

OR

7) a) Explain the three wire method with neat sketches. (7)

b) With neat sketch explain the electrical and electronic comparator. (8)

UNIT - IV

8) a) Explain the procedure of „alignment tests‟ to be done on a drilling machine. (7)

b) What are the elements of surface texture explain with a neat sketch. (8)

OR

9) a) Explain the details of construction, principle and operation of CMM. (9)

b) What is meant by alignment tests machine tools? Why they are necessary? Explain. (6)

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