Reg No.:

Max. Marks: 100

b)

D3821 Pages: 2

Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
THIRD SEMESTER B.TECH DEGREE EXAMINATION, APRIL 2018

Course Code: AU201
Course Name: S.I. ENGINES AND COMBUSTION (AU)

PART A
Answer any three full questions, each carries 10 marks

Compare the actual and fuel-air cycles for a gasoline engine.

Derive an expression for the efficiency of a diesel cycle with PV and TS
diagram.

The bore and stroke of an engine working on the Otto cycle are 17cm and 30cm
respectively. The clearance volume is 0.001025m* .Calculate the air standard
efficiency.

What are the assumptions made in air standard cycle analysis?

Give a brief comparison of Diesel and Otto cycles for the same compression ratio
and for the same heat input.

What are the different types of air motions in the engine cylinder? What is the
significance of each?

List the factors influencing flame propagation during combustion.

What are the different methods used to control the detonation in a SI engine?
Define octane number of a fuel.

Discuss the air-fuel ratio requirements of a S.I. engine.
How Pre-ignition can lead to Detonation?

PART B
Answer any three full questions, each carries 10 marks

With a neat sketch explain the methods used for Ignition advance.

With suitable sketch, explain the following Acceleration circuit in a Solex
carburettor.

Describe the Magneto ignition system.

Compare direct and indirect injection methods.

Explain theoretical scavenging process.

Discuss the various scavenging systems.

Discuss the port timing diagram of a two stroke engine.

What are the various scavenging parameters?

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Duration: 3 Hours

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