1. OPOC TWO-STROKE
ENGINE
Topic Seminar Presented by:
Ashok Kumar . Y. G
4PS06AU003
Under the Guidance of:
Mr.K.B.Sidde Gowda
Associate Professor
Dept. Of Automobile Engg.

2. Introduction
 Engine : Device that transforms one form of
energy to another form.
Heat engine:
Classification based on combustion process
Internal Combustion Engine
External Combustion Engine
Classification based on mechanism
Reciprocating Engine
Rotary Engine

3. Reciprocating engine
Classification based on arrangement of
cylinders
• Inline Engine
• V Engine
• Radial Engine
• Delta Engine
• X Engine
• H Engine
• U Engine

4. Reciprocating engine
 Opposed cylinder
 Opposed piston

5. Opposed cylinder Engine

6. Opposed piston Engine

9. Two-Stroke engines:
The two stroke engines is the one in which,
one revolution of crank shaft completes all
the processes(suction, compression,
ignition, expansion and exhaust).
The main drawbacks of the two-stroke
engine are lake of efficiency and escaping
of un-burnt fuel.

10. OPOC Two-Stroke engine:
 Developed by:
EcoMotors International, a startup based
in Troy, Michigan.
 According to the company the two-stroke
engine is up to 50 percent more efficient than
most vehicle engines and pollutes far less
than a conventional two-stroke engine.

11. OPOC engine

12. OPOC engine

13. OPOC engine

14. OPOC piston crowns

16. Explanation:

17.  The engine uses two piston movements per
cycle(w.r.t. four-stroke engine), instead of
four, and each cylinder contains two
opposing pistons, instead of one.
 A single crankshaft sits in between pairs of
cylinders.
 The design relies on precise computerized
control of all the components.

18.  When the outer piston moves away from
center of the cylinder the inner piston moves
in opposite direction, resulting in opening of
intake manifold.
 The fresh air enters into the cylinder.
 Then the pistons travel near the center of the
cylinder compressing the air.

19.  The temperature of air increases. At that time
fuel will be injected and the combustion takes
place.
 When Expansion takes place exhaust
manifold will be opened before the intake
manifold opens and then the burnt gas will
starts to escape.
 Addition to that, when inlet manifold opens,
scavenging process takes place.

20. Technologies which have helped to reduce the
emissions of the OPOC two-stroke engine:
 An electric turbocharger allows for "variable
compression ratio," whereby the inlet
pressure fed into the engine's cylinders is
varied to maximize efficiency.
 An approach called asymmetrical port timing-
-opening the intake and exhaust ports at
different times--helps improve the efficiency
of gas exchange.

21.  High pressure injection and computerized
control of injection improve the overall
efficiency of the cycle.

22. Electrically Controlled Clutch:

23.  The development in clutch technology
enables customers to take advantage of the
engine’s modular displacement capability.
 The clutch assembly is housed between two
engine modules, and is engaged when vehicle
power demands require both modules to
deliver power.

24.  When the power of the second module is not
needed, the clutch is disengaged, allowing
the second engine to stop completely.
 This not only improves fuel economy by
reducing parasitic losses, but also improves
the efficiency of the primary module.

25. Figure of two module OPOC with the electrically
controlled clutch:

26. Advantages:
 Putting two pistons inside each cylinder also
means that each piston only travels half as far
as it normally would in a two-stroke engine,
allowing the engine to run faster.
 Delivers twice as many power strokes per
revolution
 Requires few parts compared 4-stroke
engine.

27.  These factors, account for a 15 percent
efficiency improvement.
 Having half as many parts as a conventional
engine (the OPOC does not have cylinder
head or valve-train components, and it has
fewer bearings) helps to reduce friction and
heat loss.

28.  Multiple engines, or "modules," can be used
together to boost the fuel efficiency of a
vehicle by as much as 45 percent.
 In addition to the efficiency gains of the
engine itself, extra modules can be
deactivated when they aren't needed using
electrically controlled clutch. This also
increases the fuel efficiency upto 50%.

29. Advantages:
The engine advantages engine offers:
 High power-to-weight ratio
 High power-to-volume ratio
 Use of a variety of fuels including gasoline,
diesel, natural gas, JP8 and hydrogen
 Assisted HCCI combustion using proprietary
diesel fuel system
 Conventional parts, materials and
maintenance

30. Difference between common and OPOC two stroke
engines:
Sl.no common OPOC
1. Piston moves till the TDC. Piston moves only till the center of
the cylinder.
2. Only one piston inside the cylinder. Two pistons inside the cylinder.
3. Less efficient. More efficient.
4. Sensors are not required. Sensors are required and important.
5. Electrical clutch is absent. Electrical clutch is present.
6. One cylinder on the side of the Consists of two cylinders on either
crankshaft. side of a crankshaft.

31. Application:

33. Reference:
 Engine Efficiency: The Ecomotors Solution
Joey Daubert,Andy Lawniczak Twelfth
Annual Freshman Conference Paper #2308
 CONCEPT BY: EcoMotors International, Troy,
Michigan.
 www.ecomotors.com
 www.navistar.com
 http://thekneeslider.com/archives/2009/12/
21/ecomotors-opoc-two-stroke-engines-
opposed-piston-opposed-cylinder/

34. THANK YOU