automobile enginering part b questions

ME2354 AUTOMOBILE ENGINEERING KLNCE

PART B QUESTIONS

UNIT I VEHICLE STRUCTURE AND ENGINES

I.Chassis

1. Draw the layout of an automobile and indicate the various components (OR) VEHICLE CONSTRUCTION (OR)Draw the layout of conventional chassis with a neat diagram and explain about the various parts on it.

2. Explain the classifications of chassis according to engine arrangement and drive

(i)conventional chassis (ii)semi forward ,full forward chassis (iii) front wheel ,rear wheel drive and four wheel drive

II.Frame

3. Explain the construction and types of frames used in automobile with neat sketch

4. Explain the following terms.(i)Load distribution in frames (ii)Frame materials (iii)Defects of frame

III.Engine

5.Explain the various components of engines with their functions and materials

6.Explain the classification IC ENGINE based on the following

(i) cylinder arrangement (ii) valve arrangement .

IV.Aerodynamic effects and vehicle body design(Self study topics)

7.Explain the various forces acting on a body of automobile and its aerodynamic effects

8.What are the aspects considered in the body design

UNIT II ENGINE AUXILARY SYSTEM

8. Explain the working principles of electronically controlled gasoline injection system

9.Explain the following (i) Monopoint Injection System (ii)Multi point injection system

10.Electronically controlled common rail direct injection (CRDI) with neat sketch

11.What is unit injector ?How its controlled electronically?

12.Explain Types of electronic ignition system

(i)transistorized ignition (ii) capacitive ignition(iii)Distributor less ignition.

13.Explain battery ignition and magneto ignition with neat sketch.

14.Explain with neat sketch of engine emission control by three way catalyst controller and give merits ,demerits

15.Explain with neat sketch of turbo charger and supercharger


UNIT III TRANSMISSION SYSTEM

15.Define clutch and Explain the working principles of the following clutch

(i) Single plate (ii) Multi plate (iii)Diaphragm clutch (iv) centrifugal clutch

16.Define gear box and explain the following types of gear box with neat sketch

(i) sliding mesh (ii) constant mesh (iii) synchromesh gear box

17.Explain the working principles of torque converter and fluid flywheel with neat sketch

18.Explain the constructional operation of Differential.

19.Explain the different types of rear axle with neat sketch

(i) Torque tube drive (ii) Hotch kiss drive

20.Write short notes on (i) Propeller shaft (ii)universal joint (iii)slip joint

UNIT IV STEERING SYSTEM,BRAKES AND SUSPENSION

21.Describe briefly various steering geometries

22.Explain the types of steering gear boxes

(i) Recirculating ball type (ii) Rock and pinion gear type

23.sketch and working principles of power steering system

24.Sketch and working principles of Telescopic type shock absorber

25. sketch and working principles of pneumatic brake system

26. sketch and working principles of Hydraulic brake system

26. sketch and working principles of disc and drum brake system

27. sketch and working principles of Antilock braking system

28.Explain briefly working principles of the following

(i) Master cylinder (ii)tandem master cylinder (iii)Wheel Cylinder

29.Explain elements of suspensions and types of front independent and rear independent suspension system

UNIT V ALTERNATIVE ENERGY RESOURCES

30.Describe briefly (i) Compressed natural gas (production,advantages and disadvantages) (ii)LPG (production,advantages and disadvantages)

31.Explain briefly hydrogen used in automobiles(Advantages, disadvantages)

32.Explain the working principles of electric vehicles and hybrid electric vehicles

33.What is fuel cell? Explain the working principles of types of fuel cells

34.Write short notes on biodiesel ,bio ethanol


UNIT I VEHICLE STRUCTURE AND ENGINES

1. Draw the layout of an automobile and indicate the various components (OR) VEHICLE CONSTRUCTION (OR)Draw the layout of conventional chassis with a neat diagram and explain about the various parts on it.


Components of chassis

1.Frame

2.Front axle

3.Steering system

4.Rear axle

5.Suspension System

6.Transmission

7.Brake

8.Engine

9.Electrical system

1.Frame:

The frame designed in general consists of two longitudinal or side members made in the form of pressing of channel section.It supports the engine body, wheels and transmission system.


2.Engine:

The moving power for a moving car,wheels and other parts of automobile is provided by the engine.It generally consists of an internal combustion engine.It may be either the spark ignition or combustion ignition engines.For better performance,safe working and long engine life,the engine requires four system namely fuel system,cooling system,lubricating system.

3.Steering system

The control of an automobile is done by means of a steering system which provides directional changes to the moving automobile and with help of accelerator and gear shift lever as well as the brakes.

4.Front axle

It is a major component of a automobile

2.Explain the classifications of chassis according to engine arrangement

Classification of chassis

1.According to its control

-Conventional chassis

-semi forward chassis

-Full forward chassis

2.According to fitting of engine(or) engine drive


1.Front engine rear wheel drive

2. Front engine Front wheel drive

3.Front engine Four wheel drive

4.Rear engine Rear wheel drive

4.Explain the construction and types of frames used in automobile with neat sketch

Frame: Frame is a rigid structure that hold all the major parts of the vehicle.

Functions of frame:

1.To support the chassis components and the body (Engine,Road wheels ,body)

2.To withstand bending and twisting stresses due to the fluctuation of rear and front axle.

3.To resist the centrifugal forces when cornering


4.To bear thrust,acceleration and braking torque

5.To serve as a bed for fuel tank,battery and other mounting units

6.To accommodate suspensions system.

Types of frame section or steel section

1.Channel section

2.Box section

3.Tubular section

Type of frame section Behaviour

Channel section

Excellent resistance to bending.Resistance increase as depth of section is increased.

Tubular Section

Excellent resistance to Torsion.Resistance increased as diameter is increased.

Box Section Good resistance to both bending and torsion.

Types of frame

1.Conventional frame

2.Frameless construction (or )unitized body design

1.Conventional frame (for passenger car)


Conventional chassis frame consists of two longitudinal members which are referred to as side members. These members are braced by cross members (horizontal members) at the front and rear of the frame.

To improve the torsional stiffness of the frame a diagonal cross brace arrangement is added to the centre of the frame.

The side members must taper in narrow at the front to provide shorter turning radius of front wheel and give improved support to the engine assembly.

The front and rear ends of the side members are swept upwards to accommodate the movement of the axle due to springing and also kept the chassis height low.This also avoids impact due to rear axle bouncing.

Conventional frame (for commercial vehicles)

The arrangement of the commercial vehicle chassis frame is similar to that of the passenger cars frame but is must be capable of carrying heavier and more varied loads.

The side members are not swept up at the front and rear to allow for the vertical movement of the axles.

In this type of frame more space is available for front road wheels to turn on the larger vehicle and the ground clearance is greater.


2. Frameless construction (or )unitized body design (or) integral construction

Today, almost all passenger cars, most vanes and even some buses are of integral construction also known as monocoque construction.

In this body design , the frame and body are combined as one unit. all the members of a unitized body are load carrying members.

The floorpan,r oof,I nner aprons, quarter panels, pillars and rocker panels are integrally joined to form unitized body.

The strength and rigidity of the unitized body is achieved by body design rather than by having a heavy steel frame to support the body.

In this body design ,body sheet metal is fabricated into a box design which provides good resistance to bending and torsion.

Advantages:This construction are low weight and the ability to style the outer body panels as desired.

Diadvantages:

Construction cost is high

Engine noise is high

4.Explain the following terms.

(i)Load distribution in frames (ii)Frame materials (iii)Defects of frame

Load on chassis frame

Static load- Loads due to chassis parts like engine, transmission, steering, body constantly acting on the vehicle

Inertia load-While applying brakes, inertia loads of short duration are applied on the vehicle.


Overload-overloading a vehicle beyond design capacity

Impact load-Due to collision of the vehicle with another object, it is subjected to externally applied impact loads.

Loads on short duration-while crossing a broken patch of road,a vehicle is acted upon by heavy and suddenly applied loads of short duration.

Defects on frame

Cracks

Broken welds

Buckling

Corrosion and rusting

The following methods are used to avoid rust formation

1.Use of mild steel,carbon steel,nickel alloy steel sheets

2.Use of zinc enriched primer paints

3.Plastic coating

4.Providing plenty of drain holes to allow trapped water to run out.

MATERIALS FOR FRAME

Mild steel

Carbon steel

Nickel alloy steel

Composition of nickel alloy steel (Carbon- 0.25 to 0.35%

Manganese- 0.35 to 0.75%

Silicon-0.30%

Nickel- Phosphorus-0.05%

Sulphur-0.5%

5.Explain the various components of engines with their functions and materials


IC ENGINE COMPONENTS

Functions of engine components

1.Cylinder

-It contains the charge which gets compressed when piston reciprocates inside the cylinder.

Material: Grey cast iron

2.Cylinder head

-To seal the working ends of the cylinder and not to permit entry and exhaust gases on over head valve engines.Material:Grey cast iron ,aluminium and steel.

3.Inlet and exhaust valve

-To control the quantity of fresh charge admitted into to the cylinder during suction stroke and control the quantity of gases escaping from the engine cylinder during exhaust stroke.

Material:-nickel chromium steel,silicon chromium

4.Piston and piston rings

-To suck and compress the fresh charge

-To transmit the gas force to the connecting rod

-To force the exhaust gases from the cylinder

5.Rings:


-Upper ring: Prevents leakage of burnt gases in to lower ring

Lower ring: Provides good sealing between the piston and cylinder.

6.Connecting rod:

-To provide passage for lubricating oil from big end to small end through a groove at its centre.

7.Crank shaft:

-To convert the reciprocating motion of the piston to rotary motion and drives the camshaft.

8.Camshaft:To operate inlet and exhaust valve

Engine parts material

Cylinder block –Grey cast iron

Cylinder liner-special alloy casting withmanganese,nickel,chromium,silicon

Cylinder head- Grey cast iron,aluminium alloy

Piston-aluminium alloy

Piston rings-high grade castiron

Connecting rod-forged alloy steel,

Crank shaft-heat treated alloy steel

Valves-nickel chromium steel,silicon chromium

Cam shaft-case hardened steel,grey iron

Flywheel-hardened steel

6.Explain the classification IC ENGINE based on the following

(i) cylinder arrangement (ii) valve arrangement .

Classification IC ENGINE

With respect to Number of stroke per cycle

Two stroke

Four stroke

With respect to number of cylinder


1.Single cylinder 2. two cylinder 3.Three cylinder 4.Four cylinder 5.Six cylinder 6.Eight cylinder

Classification IC ENGINE

With respect to Number of stroke per cycle

Two stroke

Four stroke

With respect to number of cylinder

1.Single cylinder 2. two cylinder 3.Three cylinder 4.Four cylinder 5.Six cylinder 6.Eight cylinder

automobile enginering part b questions

Documents