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B.Tech. Engineering Programmes (MLEP)Model Question Paper with Synoptic Answer Key

TML101: Automobile Engineering -1

Maximum Allowed Time: 180 Minutes Maximum Marks: 100

Instructions for the students

1. All questions are compulsory.2. "Long Answer type Question (LAQ)" is a supply type question of 20 marks, which requires typical answer of about

60-80 lines in about 32-40 minutes.

3. "Short Answer type Question (SAQ)" is a supply type question of 05 marks, which requires typical answer ofabout 15-20 lines in about 08-10 minutes.

4. Use of non-programmable type of scientific calculator is allowed.5. Draw neat diagrams wherever necessary.

Q No. Question (Q) Q Marks

Long Answ er type Questions (LAQs)

1 (a) Discuss detonation & knocking in S.I. Engines with help of schematic.

(b) Explain normal and abnormal combustion is C.I. engines with P diagram.

Synoptic Answer Key

SN Key Marks

Q. 1 (a) Detonation / Knocking

- abnormal combustion

- occurs because of peculiar movements of flame front resulting in

dashing and hence noise

- explain with schematic (Fig. 5.11 pg. 178 of Mathur Sharma)

Explanation7 marks

Schematic3 Marks

Q. 1 (b) P diagram (Fig. 6.2) of Mathur Sharma (Page 217) 3

Normal stapes Ignition delay period, Rapid or uncontrolled combustion,

Controlled combustion and afterburning.

4

Abnormal stapes Diesel knock (Fig. 6.10 Pg. 228) 3

20


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2 (a) Discuss at least 3 methods to determine Frictional power in performance testing.

(b) Define

(i) B.P.

(ii) I.P.

(iii) mechanical(iv) Brake thermal efficiency

(v) Indicated thermal efficiency

Synoptic Answer Key

SN Key Marks

02 (a) Three Methods(1) Morse test(2) Willans line Method(3) Motoring test

3

Explanation of each of 1st two i.e. Morse, Willans line

(1) Morse Test

B.P. = I.P F.P. = I1 + I2 + I3 + I4 (F1 + F2 + F3 + F4)

When 1st cylinder cut off

B.P1 = I2 + I3 + I4 (F1 + F2 + F3 + F4)

I1 = B.P. B.PSimilarly I2, I3 and I4 are calculated

Total Indicated Power = I1 + I2 + I3 + I4 = I.P.Then Frictional Power = I.P. B.P.

(2) Willians Line Method

(i) A graph of fuel consumption for different loads against B.P. is plotted.

(ii) Ve X axis interacts is frictional power.

2 x 2 = 4

02 (b) B.P. Power available at crankshaft

I.P. Power available at piston

Mechanical efficiency = mech = B.P. / I.P.

Brake thermal efficiency = B.P. / nif x c.v.

Indicated thermal efficiency = I.P. / nifx c.v.

2 marks

each x 5= 10

marks

20

F.P B.P

FuelConsumption


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3 (a) Write short note on purpose and design of different types of Piston Ring.(b) Why aluminum cylinder heads are commonly used? Discuss its drawbacks?

Synoptic Answer Key

SN Key Marks

(a) Piston Rings perform three functions

01. Sealing02. Remove oil03. dissipate heat

3

Piston Ring Types

01. Compression Rings02. Oil Control rings01. Compression Rings

i) Form seal between piston and cylinder walls.

ii) Generally made of cast iron

iii) Typical soft coatings used an graphite, phosphate, iron oxide, or

molybdenum

iv) hard coating used is chromium

1.5

Figure 8.49 2

Oil Control Rings are

01. Segmented oil ring02. Cast iron oil ring.Both types of rings are slotted so that excess oil from cylinder wall pass

through ring

1.5

Figure 8.50 2

(b) Aluminum herds are commonly used because of low weight

Weight (9 to 18 kg)

Low Weight means low load means more fuel economy

3

Disadvantage

Aluminum expands & contracts almost twice as much as cast iron. Thiscreates problems.

When aluminum head is meted with iron, the difference is thermal expansion

between head and block creates a scrubbing stress. Increased thermal stresscan lead to cracking.

3

Fig. 9.16 2

Fig. 9.17 2

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4 (a) Discuss different components used in Liquid Cooled System with help of sketches.(b) Discuss typical turbocharger system with help of sketch.

Synoptic Answer Key

SN Key Marks

(a) Liquid CooLed System

Need of cooling system

-L.I.G. Engines generate heat which needs to be dissipated.

Liquid Cooling, Air Cooling

1

Liquid cooling

- Most efficient method of cooling

Components

-Coolant, water pump, radiator, thermostat

1

(1) Coolant should not freeze. Hence antifreeze coolant used water +ethylic glycol

1

(2) Water pump driven by crankshaft thro pulleys and v-best. 1

Centrifugal type pump

Fig. 11.34, pg. 261

2

(3) Radiator is basically a heat exchanger. It has series of tubes & funs that

expose coolants heat for better heat transformer

Types cross flow, down flow

1

Fig. 11.35 pg. 261 2

(4) Thermostat helps to prevent overheating of engine. Composed of waxand metal pellet.

Fig. 11.42 pg. 264

2

(b) Turbocharger increases the amount of airflow and hence power output of

engine

1

Components

Turbine or hot wheel

Shaft

Compressor or cold wheel

Waste gate valve

Actuator

Center housing & rotating assembly (CHRA)

3

Fig. 12.32 6

20

Short Answer type Questions (SAQs)5 Discuss the difference between petrol and diesel engine (Any five points)

Synoptic Answer Key

SN Key Marks

Petrol Engine Diesel Engine

(1) Spark ignition (1) Compression ignition

(2) low compression ratio 6-11 (2) High compression ration 13-22

(3) High speed engine (3) low speed

(4) Lighter (4) Heavier

(5) Otto Cycle (5) Operates on Diesel Cycle

1 mark

eachpoint

05

6 Discuss Rope Brake dynamometer with the help of neat sketch.

Synoptic Answer Key

SN Key Marks01 Fig. 18.16 pg. 643, Mathur Sharma 3

02 (i) Dynamometer measures brake power

(ii) Rope is used to apply braking torque (T) and B.P. is calculated by

B.P. =60

2 NT

2

05


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7 Explain principle of Hybrid Vehicles?

Synoptic Answer Key

SN Key Marks

1) Uses electronic motor + gasoline engine2) For example Toyota Prius (Japan)3) Electronic motor also acts as generator4) Engine is 4 cylinder Ackinson cycle engine5) When engine is running motor charges battery (working as

generator)

6) Once NIMH batteries are charged, vehicle switch from gas tobattery.

1 mark

for 5

pointseach

05

8 Draw a neat labeled sketch of Pellet type Catalytic converter.

Synoptic Answer Key

SN Key Marks

Fig. 12.21 (pg. 290) 3

Correct labels 2

05

End of Model Question Paper with Synoptic Answer Key


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TML101: Automobile Engineering-1









1 (a) What occurs in the combustion chamber of a four stroke engine? Name the four strokes of afour-stroke cycle engine.

(b) What precautions should be taken when cleaning an engine prior to its removal? Explain

thermal cleaning.(c) Describe the functions of connecting rod and crankshaft. Also explain the function of cylinder

lines?

Synoptic Answer Key

SN Key Marks

5

5

10

2 (a) Where and how is the camshaft mounted on overhead camshaft engines?

(b) What is used in some engines to limit the side movement of the pushrods? Define galling

wear.

(c) Describe briefly different cooling systems.

Synoptic Answer Key

SN Key Marks

5

5

10

3 (a) What are the objectives of lubrication?

(b) Describe the construction and function of gear type oil pump? How does it differ with rotor-type oil pump?

(c) What are the advantages of preheating intake air?

Synoptic Answer Key

SN Key Marks

01.

5

10

5


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4 (a) Write short note on air filter.

(b) Explain function and working of catalytic converters.

(c) Explain intake and exhaust valves. Explain in detail important valve components of four

stroke engine.

Synoptic Answer Key

SN Key Marks

5

5

10

Short Answer type Questions (SAQs)

5 On what bases the automobile engines can be classified?

Synoptic Answer Key

SN Key Marks

05

6 What are the advantages and disadvantages of diesel engines in a passenger car?

Synoptic Answer Key

SN Key Marks

05

7 What are the advantages of two stroke cycle engine over four stroke cycle engine?

Synoptic Answer Key

SN Key Marks

05

8 Write short note on piston and piston rings.

Synoptic Answer Key

SN Key Marks

05

End of Model Question Paper

Synoptic Answer Key not available


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6B.Tech. Engineering Programmes (MLEP)Model Question Paper with Synoptic Answer Key










1 (a) What is the function of gasket? Give classification of engine gaskets.

(b) Name some applications of hard gaskets. Where are flexible sealers most often used?

(c) What are the various materials used for gasket? Give general gasket installation procedure.

Synoptic Answer Key

SN Key Marks

5

5

10

2 (a) What happens in an electrical circuit when the resistance increases? What is the difference

between voltage and current?

(b) What kind of solder is used to repair electrical wiring? What is an SPST switch?

(c) Describe how semiconductors work. What are P-type and N-type semiconductors?

Synoptic Answer Key

SN Key Marks

5

5

10

3 (a) Explain Light-emitting diodes and Zener diode.

(b) Explain the principle of multiplexing.

(c) Describe the basic electronic logic gates.

Synoptic Answer Key

SN Key Marks

5

5

10

4 (a) Explain the purpose of a battery and describe the basic parts of an automotive battery.

(b) Explain the chemical reaction that occurs to produce current in a battery. Describe the

differences, advantages and disadvantages of the different types of batteries.

(c) Explain the purpose of the starting system. List the components of the starting system.

Synoptic Answer Key

SN Key Marks

5

10

5



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5 Explain the different types of magnetic switches and starter drive mechanism.

Synoptic Answer Key

SN Key Marks

05

6 Explain the purpose of charging system. Identify the major components of the charging system.

Synoptic Answer Key

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05

7 Describe the different types of headlights and how they are controlled?

Synoptic Answer Key

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05

8 Describe the operation of ignition coils, spark plugs and ignition cable in brief.

Synoptic Answer Key

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05




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1 (a) What are the gasoline additives? Give their names and functions of each of them.

(b) Sketch a mechanical fuel pump and describe its working.

(c) What are the functions of fuel feed system of an automobile? Describe briefly the various

systems of supplying fuel from the fuel tank to the engine cylinder.

Synoptic Answer Key

SN Key Marks

5

5

10

2 (a) What is a carburetor and carburetion?

(b) Give classification of carburetors? Explain it in brief.

(c) What are the functions of fuel pump and injector in diesel engine vehicles? Describe briefly

the functions of various parts of an injector.

Synoptic Answer KeySN Key Marks

5

5

10

3 (a) Why is the clutch placed between the flywheel and transmission? What are the requirements

of clutch?

(b) Describe the construction of a clutch plate? What are the different types of friction materials

used on a clutch plate?

(c) Describe the construction and working of the following

i) Hydraulic clutch

ii) Diaphragm clutch

Synoptic Answer Key

SN Key Marks

5

5

10


11/16

4 (a) Explain the function of transmission in an automobile. Give a classification of transmission.

(b) What are various components of transmission system? Describe their role. Explain theprinciple of synchromesh gearing.

(c) Explain need of fuel filters.

Synoptic Answer Key

SN Key Marks

5

10

5


5 Describe the advantages of LPG.

Synoptic Answer Key

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05

6 Why does knocking occur?

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05

7 What are the defects in a simple carburetor?

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05

8 What are the methods of fuel injection in the Diesel engines?

Synoptic Answer Key

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05




12/16


TML104: Automobile Engineering 4









1 (a) Explain the problems encountered in FWD drivelines? What are the possible causes andcorrective remedies?

(b) Write short note on Automotive air-conditioning.

Synoptic Answer Key

SN Key Marks

Q. 1 (a) Problems (See pg. 907)

(1) Vibrations in steering

(2) Vibrations thro vehicle

(3) Vibrations thro Vehicle at low speeds

(4) Vibrations during acceleration

(5) Grease dripping

(6) Snapping noise

Any Five

problemswith

diagrams

&remedy 2

markeach.

Q. 1 (b) (1) Ventilation System need to ventilate 2

(2) Heating System Heating in winter season 2

(3) Cooling System Basic principle vapor compression cycle,refrigerants used, refrigerating effect achieved. (Fig. 48.3, pg. 1226)

Process 1-2 Refrigerating effect, Process 2-3, compression Process

3-4, Condensations is condenser and process 4-1 is throttling isexpansion valve or capillary tube

6

20

2 (a) Discuss or Tires write (i) function (ii) classification (iii) Tire construction (iv) Rating

(b) Explain different springs used in suspension systems.

Synoptic Answer Key

SN Key Marks

02 (a) (1) Tires provide traction 2

(2) Tube 2 Tubeless tries explain 2

(3) Bead, Tread, Spies 2

(4) Belted bias ply, Radial Ply 2(5) Rating eg. P195/75R14 2

02 (b) Coil springs 2

Torsion bar springs 3

Single leaf spring 2

Multiple leaf spring 3

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3 (a) List the problems that arise due to incorrect wheel alignment.(b) Explain master cylinder operation in braking system.

Synoptic Answer Key

SN Key Marks

(a) Problems effect

01 Incorrect camber setting - Tire, wear bearing wear 2

02 Too much +ve caster - hard steering etc. 2

03 Too much ve caster - instability etc. 2

04 Incorrect SAI - instability Poor return etc. 205 Incorrect toe setting - Tire wear 2

(b) Figure 44.12 (pg. 1139) 3

It converts mechanical force to hydraulic pressure 1

Working (1) master cylinder hydraulic

Device (2) when the brake pedal is depressed, primary cup compresses fluid.

Piston & Primary Cup seals the system. Secondary Cup sets non-pressurized

Fluid (3) when brake pedal is released shoe return springs / piston sealsretract the piston.

6

20

4 (a) Draw a neat sketch of duo-servo drum brake. Explain its working.(b) What are Antilock brake systems? List their components and types? Define slip rate with

figure?

Synoptic Answer Key

SN Key Marks

(a) Neat sketch Fig. 45.6 Pg. 1159 3

Label Neat & correct labeling 3

Explanation four points

(1) self energizing(2) front & rear shoe actuated by double piston wheel cylinder(3) Forward rotation force on adjuster link then to secondary shoe(4) Friction developed by secondary lining is greater

4

(b)Slip rate defn =

edVehicleSpe

WheelSpeededVehicleSpe

2

- ship rate curve (Fig. 47.2) pg. 1198 3

Antilock braking Systems (1) gets pumping job rapidly than human foot(2) Mostly electronic/hydraulic pumping

(3) Components are (a) Accumulator, booster pump,

valve, master cylinder (b) Control unit

2

Fig. 47.1 pg. 1198 3

20


5 Define Differential? Explain its Functions.

Synoptic Answer Key

SN Key Marks

Differential is geared mechanism located between driving axles of a vehicle. 1

Function

Figure 36.20

2

Consider the vehicle turning a corner of radios 30 feet. Then the inner wheelsrotate to cover 46 feet and outer wheels rotate to cover 58 feet. If these

wheels rotated at same speed, vehicle turning would have been impossible.Differential rotates driving axles at different speeds.

2

05

6 Explain caster and camber.

Synoptic Answer Key

SN Key Marks

01 Wheel alignment terms

Caster angle of the steering axis of a wheel from vertical as viewed fromside of vehicle. (Pg. 1116, Fig. 43.2)

2.5

02 Camber angle represented by tilt of either front or rear wheels inward or

outward from vertical as viewed form front of vehicle. (Fig. 43.3)

2.5

05


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7 Explain manual parallelogram steering system.

Synoptic Answer Key

SN Key Marks

Purpose of steering system

(i) steering linkage(ii) steering gear(iii) steering column & wheel

2

Fig. 42.2

Components Pitman arm, idler arm, links, tie rods

3

05

8 Explain Automatic stability control

Synoptic Answer Key

SN Key Marks

Stability control systems apply brakes at any one wheel to correct over steer

or under steer. In some vehicles, stability control is also linked to electronic

suspension system.

Components

Control unit

Sensors Yaw rate sensor, wheel speed sensor, lateral acceleration sensor

(G sensor) and steering angle sensor.

2

(Fig. 47.23) 3

05

End of Model Question Paper with Synoptic Answer Key


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TML104: Automobile Engineering-4









1 (a) What is steering linkage? What is the difference between parallelogram steering linkage andrack and pinion steering linkage?

(b) Explain various types of springs used in suspension system.

(c) Explain in detail power steering used in automobiles with figure.

Synoptic Answer Key

SN Key Marks

5

5

10

2 (a) What is the difference between four wheel drive (4WD) and all Wheel drive (AWD)?

(b) Explain independent front suspension system.

(c) Draw neat sketch of telescopic shock absorber and explain its construction and working.

Synoptic Answer Key

SN Key Marks

5

5

10

3 (a) What are advantages of hydraulic brake system over drum brake system? Explain in detailhydraulic brake system. Explain construction of master cylinder with neat sketch.

(b) Explain tube type and tubeless tires.

Synoptic Answer Key

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15

5

4 (a) With help of sketch explain tire rotation.

(b) Explain four-wheel drive vehicle alignment.

(c) Draw neat sketch of disc brake and explain it. Compare disc brake with drum brake.

Synoptic Answer Key

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5

5

10



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5 Describe the different components of an automobile air-conditioning system.

Synoptic Answer Key

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05

6 What is the importance of having correct tier pressure? What are the causes of tier wear?

Synoptic Answer Key

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05

7 What does change of state mean? Why is it important to air conditioning units?

Synoptic Answer Key

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05

8 What are the different types of rear end suspension?

Synoptic Answer Key

SN Key Marks

05



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