Construction and working of a Stirling engine model

1. Title of the Mini Project
Construction and Working of a Stirling
engine model
By
LAKSHI NANDAN BORAH(DC2013BTE0140)
GUIDE:- Asst. Prof. Pallav Gogoi

2. ENGINE
An engine is a machine designed to convert one form
of energy into mechanical energy.
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3. TYPES OF ENGINE
 INTERNAL COMBUSTION: An internal combustion
engine (ICE) is a heat engine where the combustion of
a fuel occurs with an oxidizer (usually air) in a
combustion chamber that is an integral part of the
working fluid flow circuit.
 EXTERNAL COMBUSTION: An external combustion
engine (EC engine) is a heat engine where a working
fluid, contained internally, is heated by combustion in
an external source, through the engine wall or a heat
exchanger.
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4. CLASSIFICATION OF IC ENGINE
 CYCLE OF OPERATION
 CYCLE OF COMBUSTION
 ARRANGEMENT OF CYLINDER
 USES
 FUEL USED
 SPEED OF ENGINE
 METHOD OF IGNITION
 COOLING OF CYLINDER
 NUMBER OF CYLINDER
 METHOD OF GOVERNING
 VALVE ARRANGEMENT
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5. CLASSIFICATION OF EXTERNAL
COMBUSTION ENGINE
 STEAM ENGINE
 STRILING ENGINE
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6. HISTORY OF STIRLING ENGINE
Inventor = Robert Stirling (1790 - 1878)
Sought to replace the steam turbines of his days due to
frequent explosion caused by unsustainable high
pressure, killing and injuring workers
Invented Stirling engine in 1816 which did not explode
and produced more power than the steam engines
used at that time.
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7. INTRODUCTION TO STIRLING
ENGINE
 It is an external heat combustion where heat is provided
outside the cylinder.
 It operates by continuous cyclic compression and
expansion of air.
 The working fluid is subjected to different temperature
levels so that there is a net conversion of heat energy to
mechanical work.
 In this engine the working fluid is constantly held inside
the cylinder so the system is in thermal equilibrium.
 It is different from other heat engines by means of
regenerator through which hot gases move from one
chamber to another chamber.
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8. WORKING PRINCIPLE
It is an external combustion engine
The key principle of a Stirling engine is that a fixed
amount of a gas is sealed inside the engine.
The working of Stirling engine is similar to any other
engine:-
Alternate compression at low temperature and
expansion at high temperature.
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12. Fig. 1 THE WORKING PRINCIPLE OF STRILING
ENGINE
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13. TYPES OF STIRLING ENGINE
(a) Two separate piston cylinder mechanism:
(i) Alpha type stirling: double cylinder, two
piston, each piston in its own cylinder.
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14. (b) Piston displacer mechanism:
(i) Beta type: Single cylinder, power piston and
displacer piston in same cylinder
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15. (ii) Gamma type: Power piston and displacer piston in
two different cylinders: one above the other.
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16. The fabrication of a Gamma type stirling engine
Fig.5 Constructed Gamma stirling engine
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17. PARTS OF THE STIRLING ENGINE
 Hot side heat exchanger
 Cold side heat exchanger
 Displacer piston
 Flywheel
 Power piston
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18. Working of the constructed
engine
1. The heat obtained from the source gives
heat energy to the working substance
(air).
2. The air expands and moves the displacer
piston towards the crank end side.
3. The hot air passes past the piston and
expands the air and also moves the power
piston (a flexible diaphragm is used here)
4. Due to expansion, the air cools down
5. Due to inertia of the flywheel, the pistons
continue to move and drives the air to the
heating zone
6. The cycle is continued
7. The output power is obtained from the
power piston.
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19. ADVANTAGE AND DISADVANTAGE
 ADVANTAGES:-
 Silence in operation
 High efficiency
 Reliability and easy maintenance
 An important lifetime
 Availability of heat source.
 DISADVANTAGES:-
 The price
 The ignorance of this type of engine
 Variety of models
 Problems of sealing
 Heat transfers
 The lack of flexibility
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20. APPLICATIONS
The stirling engine has many applications like
 Heating & Cooling in Underwater power systems
 Function in reverse as a heat pump for heating or
cooling
 Solar power generation
 Stirling cryocoolers
 Marine engines
 Low power aviation engines
 Low temperature difference engines
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21. IMPLEMENTATION IN INDUSTRIES
Stirling engines can run directly on any available
heat source, from solar, geothermal,etc.
 Electricity production
 Alternate for motors
 Dual power output to increase engine efficiency
 Fuel saver
 Alternate for air conditioner
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22. CONCLUSION
 Even though output of engine is not sufficient to run
an entire vehicle but it can be used a secondary engine
in automobiles, and for all industrial light duty
operations. Hence the objective of designing and
manufacturing of the engine was successful and can be
implemented as a replacement for low power motors.
It’s been proved that running costs of the engine is also
very less. This will help to minimize the use of fuel and
reduce air pollution
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23. References:-
1. Andy Ross, Making stirling engines, 3rd edition, 1997 at
http://StirlingBuilder.com
2. Caleb C., A low temperature differential stirling engine for power
generation, M. E. Thesis, Lloyd University of Canterbury, 2009
3. Yonus A. Cengel, Michael A. Boles , Thermodynamics An Engineering
Approach
4. http://www.stirlingbuilder.com/new-pop-can-engine
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24. THANK
YOU
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