Building compressed air driven generator

1. Building Compressed
Air Driven Generator

2. Generator
• A generator is a device that converts mechanical
energy to electrical energy for use in an external
circuit. The source of mechanical energy may vary
widely from a hand crank to an internal combustion
engine.

3. Internal combustion engine
• An internal combustion engine (ICE) is an 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.
• In an internal combustion engine the expansion of the high-
temperature and high-pressure gases produced by combustion
apply direct force to some component of the engine. The force is
applied typically to pistons, turbine blades, or a nozzle. This force
moves the component over a distance, transforming chemical
energy into useful mechanical energy.

4. Problems associated with IC Engines
• Use of fossil fuels results in pollution and damage to
the environment.
• The emission of CO2 also results in Global Warming.
• The fossil fuels are present in limited quantity and
are depleting at a very fast pace.
• Cost of petroleum products is increasing.
• Complexity of design.

5. Compressed Air Generator
• A compressed air generator does mechanical work by
expanding compressed air.
• Compressed air engine generally convert the compressed air
energy to mechanical work through linear motion & then rotary
motion by means of conventional IC Engine.
• Air driven IC Engine is coupled with alternator it produced AC
current.

6. Working Principle of Compressed Air
Generator
• Air energy has to be stored in it by squeezing the air tightly
using a mechanical air compressor.
• The compressed air is released, it expands. This expanding
air can be used to drive the pistons that power an engine.
• The compresed air cylinder valve that allows air into
the engine.

7. Working Principle of Compressed Air
Generator
• Air is injected into the engine by using 12V electrical
injector.
• Air injector opening and closing time is controlled by the
microcontroller unit.
• Air driven IC Engine is directly coupled with alternator it's
produced AC current in electrical circuite.

8. Air Generator Circuit Drawing
Compressed air
from
compressor
Air EngineAir Cylinder Alternator
Electrical
system
Voltage
indicator

9. Air Driven Engine System Drawing
Microcontroller
Engine started by manual cranking
Injection
timing sensor
Valve
AirCompressor
12V Electrical injector
Battery

10. Adventages& Disadventages
Adventages
• Zero pollution
• Use cheapest fuel
Disadventages
• Need refiling cylinders

11. Components to be used
• Valve
• Air Pipe
• Two Stroke Engine
• Microcontrollor unit
• Injection Timing Sensor
• 12V Electrical injector
• 12V Lead Acid Battery
• Alternator

12. Building Compressed Air Generator
• To convert a conventional two stroke engine into an Air
Powered one, First of all replace the spark plug with a 12V
electrical injector.
• Now the electrical injector firing is controlled by the supply of
electrical signal from the microcontroller.
• Microcontroller unit manipulate the injection timing based on
injection timing sensor that is mounted on the engine flywheel.

13. Building Compressed Air Generator
• Microcontroller unit is power it by means of 12V lead acid
battery.
• Compressed air pipe is connected to the electrical injector.
• Between air compressor and injector, valve is provided for the
purpose of on/off the generator.
• Air driven engine is directly coupled with alternator it produced
AC current.

14. Two Stroke Engine
• A two-stroke engine is a type of internal combustion engine
which completes a power cycle in only one crankshaft
revolution and with two strokes of the piston.
• This is accomplished by the end of the combustion stroke and
the beginning of the compression stroke happening
simultaneously and performing the intake and exhaust (or
scavenging) functions at the same time.
• Two-stroke engines often provide high power-to-weight ratio.

15. Two Stroke Engine Intake
• The fuel/air mixture is first drawn into the crankcase by the vacuum that is
created during the upward stroke of the piston. The illustrated engine
features a poppet intake valve; however, many engines use a rotary value
incorporated into the crankshaft.

16. Two Stroke Engine Transfer/Exhaust
• Toward the end of the stroke, the piston exposes the intake port, allowing
the compressed fuel/air mixture in the crankcase to escape around the
piston into the main cylinder. This expels the exhaust gasses out the
exhaust port, usually located on the opposite side of the cylinder.
Unfortunately, some of the fresh fuel mixture is usually expelled as well.

17. Two Stroke Engine Compression
• The piston then rises, driven by flywheel momentum, and compresses the
fuel mixture. (At the same time, another intake stroke is happening beneath
the piston).

18. Two Stroke Engine Power
• At the top of the stroke, the spark plug ignites the fuel mixture. The burning
fuel expands, driving the piston downward, to complete the cycle. (At the
same time, another crankcase compression stroke is happening beneath
the piston.)

19. Two Stroke Engine Cycle
1=TDC
2=BDC
A: intake/scavenging
B: Exhaust
C: Compression
D: Expansion (power)

20. Two Stroke Engine Port Timing Diagram

21. Two Stroke Engine Port Timing Diagram
• Intake port opens 35° to 50° prior to TDC position which closes
same amount after TDC place.
• Exhaust port opens and closes 35° near 70° before and after
BDC place, in that order.
• Transfer port opens 35° to 60° in the proceed to BDC closes
35° to 60° after TDC place.
• Ignition takes place with spark by 15° to 20° before TDC place
as charge requires for a while to ignite.
• The exhaust and transfer ports open and close at the same
angles on also side of BDC.

22. Engine Frame

23. Engine with Alternator