2strokepetrolengine-160727163429 (1).pptx

petrol engine

1. INTRODUCTION In 1878, Dugald - clerk, a british engineer introduced a cyle which could be completed in two stroke of piston rather than four strokes as is the case with the four stroke cycle engines. the engines using this cycle were called two stroke cycle engines. In this engine suction and exhaust strokes are eliminated. Here, instead of valves, ports are used. The exhaust gases are driven out from cylinder by the fresh charge of fuel entering the cylinder nearly at the end of the working stroke.

2. 2 Stoke Engines Everything a 4 stroke engine does in 2 revolutions a 2 stroke engine does in 1 revolution of the crankshaft. How to identify 2 stroke engine from outside: Exhaust port in center of cylinder Small crankcase

3. 2 Stoke Engines part names Combustion chamber Cylinder Exhaust port Intake port Piston Connecting Rod Crankshaft Crankcase Reed valve Transfer port Still uses a flywheel (not shown)

4. WORKING OF 2 STROKE PETROL ENGINE: FUEL INTAKE: Piston moves BDC to TDC Reed Valve Is sucked open Air/Fuel/Oil mixture sucked into crankcase

5. COMPRESSION STROKE Piston moves TDC To BDC Reed Valve sealing Air/Fuel/Oil mixture is now pressurized in crankcase Air/Fuel/Oil mixture squirts into cylinder because of crankcase compression

6. COMBUSTION & EXHAUST STROKE Air/Fuel/Oil mixture is ignited in cylinder Reed valve close Every time the piston reaches TDC, there is another power stroke.

7. P-V diagram for 2 stroke petrole engine Port timing diagram

8. Port timing diagram

9. Advantages of 2 stroke petlrol engine: Smaller/lighter Cheaper Less friction No oil to change Quicker acceleration Operate at different angles

10. D isadvantages of 2 stroke petlrol engine: The lack of a dedicated lubrication system means that the parts of a two-stroke engine wear a lot faster. Two-stroke engines do not use fuel efficiently, so you would get fewer miles per gallon. Two-stroke engines produce a lot of pollution -- so much, in fact, that it is likely that you won't see them around too much longer.