Overview on power generation through Stirling engine using solar energy.

1. Power Generation Through Beta Stirling
Engine Using Solar Energy

2. INTRODUCTION TO OUR PROJECT
• Today electricity is completely integrated in human life. And to produce it, we are using
renewable as well as non-renewable resources, but unfortunately, more non-renewable
resources.
• This resources are not only polluting nature but also its depriving lives of animals, birds and ours
too... Even,It's now changing whole ecosystem and ecological cycles of the earth rapidly.
• According to latest research, the “MARIYANA TRENCH (part of pacific ocean)” which is deepest
ocean of the world has become polluted due to harmful chemicals.
• Who is responsible for all this tragedic transformation...? Answer is : We are....We humans.

3. How To Reform This Worst Situation?
• Use of renewable resource is best solution for this situation. Simultaneously
we should reduce the consumption of non-renewable resource.
• Here are some remedies through which world can be saved:-
• Solar Energy
• Wind Energy.
• Geo Thermal Energy
• Tidal Energy.
• This all resorces have multiple application beyond generating only electricity.
Such as, Solar and geo thermal energy can also be used for heating house or
any residential apartment.

4. Why Stirling Engine?
• There are many reasons behind the use of stirling engine for
electricity generation.
1. Easy to manufacture
2. Less cost involved
3. As efficient as Solar cell and many more.
• solar cell is very costly, complecated to manufacture and less efficient
in cloudy days.
• But, this system of stirling engine using parabolic dishes can generate
enough amount of heat in moderate cloudy days.

5. About Method Of Power Generation
• As shown in slide number 18, arrangement of 3 parabolic dishes will
concentrate solar rays at one focal point.
• For 3 dishes, parabolic shape to concentrate solar radiation is best,
because, parabolic shape has ability to concentrate direct radiation to
its focal point where it can generate very much high temperature.
• Using this high temperature we can generate some amount of heat
(depend upon size of dishes and season). Calculate it using Stefan–
Boltzmann law formula considering sun as a black body for rough
calculation.

6. Basics Of Parabolic Concentrator.
• This figure is showing
concentration of direct solar
radiation through parabolic
shape to its focal point.
• To find focal point you can
use this eq.
F= D^2/(16*c)
where D is rim diameter,
C is depth of dish.

7. Basics Of Stirling Engine
• Stirling engine depends on very basic law of thermodynamics. It's like this....
• “If you fill the gas inside V volume container at some P pressure, then its
pressure will increase if you heat the container because of gas expansion.
Simultaneously, your pressure inside the container will decrease if you cool
down that container because of gas contraction.”
• Using this principle, Sir. Robert Stirling made an engine which is now known as
Stirling engine. Its also known as hot air engine or striling motor.
• After much more modification on that engine now we have more compact
and efficient Stirling engines.

8. • Types of Stirling engine.
1. Alpha Stirling engine
2. beta Stirling engine
3. Gamma Stirling engine
4. Free piston Stirling engine
5. Rotary Stirling engine
6. Fluidyne engine
7. Flat Stirling engine
8. Thermoacoustic Stirling engine
• Each engine has their own advantages and disadvantages.

9. Working Of Beta Stirling Engine
• Expansion Process:-
• Hot gas above the displacer gets expand due
to heat gain from heat source and It apply
pressure force on the displacer.
• During this process, heater temp. is being
maintain at constant temperature. So its
isothermal heating process.
• So, at constant temperature, gas pressure is
reduced and simultaneously its volume
increases.

10. • Transfer/Constant Volume Heat
Rejection Process:-
• Hot expanded gas will now flow toward
power piston either through regenerator
matrix or clearance space between
displacer and cylinder (it depend on your
design that do you use regenerator matrix
or not).
• During this process, both power piston
and displacer will move simultaneously
and constant volume is maintained in the
engine during process.
• So, this is constant volume heat rejection
process, in which both the gas pressure
and temprature reduced.

11. • Compression Process:-
• Now power piston compress the gas.
And generated heat due to
compresssion is removed from fins
provided on power pston side.
• This is ideal isothermal cooling
process. Here we assume that
cooling source temperature is being
maintained constantly.
• So, gas pressure increases and its
volume decreases at constant
temperature.

12. • Transfer Process:-
• Now again that cooled gas passes
through regenerator/ between
clearance space.
• Here same like 2nd process, gas at
constant volume is transferred to
hot volume.
• But here, gas temperature start to
increase due to heat gain from
regenerator. So, its pressure and
temperature increaseas at
constant volueme.

13. Ideal Isothermal PV Diagram for stirling engine
• Process (1-2)- Expansion Process.
• Process (2-3)- Transfer/Constant
Volume Heat Rejection Process.
• Process (3-4)- Compression Process.
• Process (4-1)- Transfer Process
• Here blue and red line show
temperature of gas. Where blue
indicate cold gas and red indicate hot
gas in engine.

14. How To Design The Stirling Engine.
• Design of stirling engine was much more complex part for project. Because
design of stirliing engine is full of misclleneous concepts and more analysis.
• In order to design beta stirling engine, you have to fix 3 parameters.
1. Your max. temperature (Also known as heat sorce temperature)
2. Engine mean pressure (Pmean)
3. Your cooliing source temperature (Also known as cooling source
temperature.)
• Here, max temperature is your concentrating temperature through parabolic
dishes. And cooling source temperature is temperature of air. (If you use air as
cooling medium.)

15. • To design stirling engine we perform following analysis.
1. First Order Analysis
2. Ideal Isothermal Analysis
3. Schmidt Analysis
4. Numerical Analysis.
• Simultaneously, put your knowledge for optimization of stirling engine design
during above analysis.You can use third order analysis, like TOPSIS, FUZZY AND
LINEMAP to make more presice stirling engine design. However, third order
method can be excluded if you did first and second order analysis.
• First order analysis is use to predict engine power output from Beale number.
• Ideal Isothermal anlysis involve determination of pressure and volume in
engine by considering point to point motion of piston/displacer. (not
sinosudial motion.)

16. • Schmidt analysis will give idea about volume and pressure in the engine at any
point by considering motion of piston and displacer as siosudial.
• Apart from above analysis, numerical analysis will give actual PV diagram for
stirling engine. So, power output will be different than above analysis.
• Another main point is to optimize the stirling engine design. It involve much
more computation.
• This factors should be optimize.
1. Optimization of dead volume
2. Power piston's overlap volume
3. Mean pressure in engine
4. phase angle between displacer and power piston.
• Above parameters can imact significant effect when we design an striling
engine. Moreover gas of engine also affect egine perfomance.

17. Software Images Of Parts
• Design of parabolic dishes.
Sr. Component name Material Specifications
1 Parabolic Dish Stainless steel Dia=0.5 meter
2 Reflective glass Simple mirror Reflectivity approx.=80%
3 Supporting frame structure wooden -

18. Design in CREO PARAMETRIC 3.0:-
POWER PISTON POWER PISTON COONECTING ROD LINK
DISPLACER

19. CYLINDER
EXTRA LINK BETWEEN
CONNECTING ROD AND CRANK WEB
CRANK WEB LINK

20. LINK ASSEMBLY AT
CONNECTING ROD
MAIN DESIGN OF
ENGINE WITH
ASSEMBLY

21. Efficiency And Power Output From Different
Analysis.
Sr. No. Method of Analysis Efficiency Net work (joules) Power output
(watt)
1 Ideal Schmidt analysis 50.3% 37.65 627.249
2 Ideal adiabatic analysis 46.58% 18.45 307.37
3. Actual analysis after
considering all losses
31.27% 12.638 210.5

22. THANK YOU