Hall Ticket No Question Paper Code: AME007
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
B.Tech IV Semester End Examinations(Regular) May, 2018
Regulation: IARE R16
Applied Thermodynamics
Time: 3 Hours Max Marks: 70
Answer ONE Question from each Unit
All Questions Carry Equal Marks
All parts of the question must be answered in one place only
UNIT I
1. Describe the working principle of 4 Stroke SI engine with help of neat sketch.
What are the functional requirements of
i. Fuel injection system of CI engine
ii. Ignition system of SI engine
2. Draw and explain port timing diagram of a 2-stroke petrol engine.
What is carburation? Explain the factors affecting the carburation.
UNIT II
3. Briefly explain the stages of combustion in SI engine with help of diagram.
Discuss the effect of various engine parameters on delay period of CI engine combustion.
4. What are the general objectives in designing the SI engine combustion chamber?
Explain the phenomenon of Knocking in CI engine. Enumerate the factors that effect Knocking
in CI engine.
UNIT III
5. A single cylinder stroke cycle oil engine works on diesel cycle. The following readings were
taken when engine running at full load: Area of indicator diagram= 3 cm2, length of indicator
diagram 4 cm, spring constant= 10 bar/cm, 400 rpm, load on the brake= 380 spring
reading= 50 diameter of the brake drum= 120 cm, Fuel consumption 2.8 kg/hr, C.V. of
fuel 42000 kJ/kg, diameter of the cylinder 16 cm, stroke 20 cm. Find
frictional power
ii) mechanical efficiency
iii) brake thermal efficiency and
iv) BMEP.
Differentiate between Reciprocating compressors and Rotary compressors.
6. What are various methods to determine the friction power of an IC engine? Explain about any
one method in detail.
What is the function of compressor. Give a broad classification of compressors.
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UNIT IV
7. How an impeller and diffuser do functions in centrifugal compressor? Explain with help of
pressure and velocity variation graph.
Determine the work required by an axial flow compressor having eight stages with 50% reaction
to compress the air for the pressure ratio of 4:1. The air enters the compressor at 200C and
flows through it with a constant speed of 90 m/s. The rotating blades of compressor rotate with
a mean speed of 180 m/s. Isentropic efficiency of the compressor may be taken as 82%. Also
determine the blade angles.
8. Air at temperature of 300 K flows through in a centrifugal compressor running at 18000 rpm.
The other data given as follows:
Isentropic total head efficiency 76%
Outer diameter of blade tip 550 mm
Slip factor 0.82
Calculate the temperature rise as the air passing through the compressor and the static pressure
ratio
Prove that for a 50% reaction staging in axial flow compressor the stator and rotor blades are in
symmetry.
UNIT V
9. How under cooling and superheating of refrigerant affects the performance of vapor compression
refrigeration system.
An air refrigeration system working on Bell-Coleman cycle takes air into the compressor at 1 bar
and -5°C. It is compressed in the compressor to 5 bar and cooled to 25°C at the same pressure. It
is further expanded in expander to 1 bar and discharged to take the cooling load. The isentropic
efficiency of expander and compressor are 85% and 90% respectively. Find Refrigeration capacity
of the system for 40 kg/min air circulation, capacity of motor required to run the compressor
and C.O.P of the system.
10. With help of neat diagram explain the working of vapour absorption refrigeration system.
What is refrigerant? What are the desired properties of refrigerant? Explain in detail.