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Petrol & Diseal Engine PowerPoint Presentation
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Petrol & Diseal Engine

Petrol & Diseal Engine

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Petrol & Diseal Engine

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  1. Petrol & Diseal Engine Submittedby: MangukiyaDhruvit(131120109058) Gujarati Kartik (131120109028) Guided by: SanganiPrashant (131120109093) Mr.BhaveshChaudhari Asst. Prof. Mechanical Engg. Dept. LimbaniRavi (131120109053) DhameliyaSahil (131120109019) Pacific School Of Engineering, Surat

  2. Engine components 1. Cylinder 9. spark plug 2. Cylinder head 10. inlet valve 3. Piston 11. exhaust valve 4. Connecting rod 12. cooling fins 5. Crank and crankshaft 13. carburretor 6. Crank pin and bearings 14. flywheel 7. Piston rings 15. main bearings 8. Gudgeon pin 16. valve mechanism

  3. CLASSIFICATION OF I.C ENGINE :The internal combustion engines are classified based on the following systems 1) based on number of strokes per cycle : (a)four stroke engine in which one cycle is completed in four strokes of the piston in two revolutions of the crankshaft. (b)two stroke engine in which one cycle is completed in two strokes of the piston in one revolutions of the crankshaft.

  4. 2) Based on thermodynamic cycle used : (a) Constant volume combustion cycle or Otto cycle. (b) Constant pressure combustion cycle or diesel cycle. (c) Partly at constant volume and partly at constant pressure combustion cycle or dual combustion cycle. 3) Based on number of cylinders : (a) Single cylinder engine. (b) Multicylinder engine.

  5. 4) Based on arrangement of cylinder : (a) In line engines : in this all the cylinder are arranged with their axes parallel and transmit the power to a single crank-shaft. (b) V-engines : these engines contain two banks of cylinder connected to same crank and crank-shaft. Their axes are inclined to each other. (c) Radial engines : in this the cylinders are arranged radially and are connected to a single crank-shaft. (d) Opposed cylinder engine :in this engine there are two cylinder banks which are located in the same plane on opposite sides of crankshaft. (e) Opposed piston engine : in this engine cylinder houses two pistones, each of which drives a separate requires no cylinder head.

  6. 5) Based on ignition system : (a) Spark ignition (s.i) engines: petrol engines use the spark ignition system for igniting the compressed charge. (b) Compression ignition (c.i) engines : diesel engines utilize the high temperatures raised due to high compression ratio of the cylinder. 6) Based on cooling system : (a) Water cooled engines. (b) Air cooled engines. 7) Based on fuel used : (a) Petrol engines. (b) Diesel engines. (c) Gas engines (d) Bi-fuel engines : these engines use the main fuel as gas and the liquid fuel is used for the starting purposes.

  7. 8) Based on fuel supply system : (a) Carburettor engines : in such engines the mixture of petrol and air from carburettor is supplied to the engine cylinder. (b) Solid injection engines : in case of diesel engines the fuel is injected with the help of a fuel pump. (c) Air injection engines : in certain diesel engines the fuel is injected into the cylinder with the help of compressed air. 9)Based on lubrication system : (a) wet sump lubrication (b) Dry sump lubrication (c) Pressure lubrication

  8. Comparison between s.i.(petrol) engine and c.i. (diesel) engine

  9. Two stroke engines • In two stroke engines, one cycle is completed in one revaluation of the crankshaft by eliminating the suction and exhaust strokes. • However, the suction and exhaust processes are carried out simultaneously during the compression and expansion strokes. • The working of s.i. and c.i engines working on two stroke cycle are being describe below.

  10. Working two stroke (s.i.) engine • Fig. shows the schematic diagram of two stroke engine. In this type of engine the valves of the four stroke engine art replaced by ports which are three in numbers, namely transfer port, inlet or induction port and exhaust port.

  11. Consider that the piston is at T.D.S. which has the high pressure and high temperature gases of the previous stroke and the fresh charge in the crank case. • When the piston moves from T.D.S. to B.D.C., the burnt gases expand and develop the motive power. • After completion of about 80% of expansion stroke, the piston uncovers the exhaust port and some of the products of combustion escape to atmosphere. • During the upward motion of the piston from B.D.C. to T.D.C., the piston fist uncovers the inlet port allowing the fresh charge to be admitted into the crank case due to the partial vacuum created and then it uncovers the transfer and exhaust ports. • The fresh charge admitted into cylinder in its previous stroke is now compressed. Before the end of compression stroke a spark is supplied which burns the fuel air mixture. • Cycle is again repeated.

  12. Working of two stroke c.i. engine • Fig shows the schematic diagram of a two stroke diesel engine. • The fuel is supplied with the help of fuel injection pump and the injector to the cylinder. • The working of diesel engine is similar to two stroke S.I. engine except that only air is inducted into the crank case of C.I. engine in place of mixture of fuel and air.

  13. Consider the piston at T.D.C. when piston moves down, the hot gases expand. During its downward motion, the piston firstly uncovers the exhaust port and a little later it uncovers the transfer port. • The air compressed during the previous stroke in the crank case is transferred into the cylinder via the transfer port. This incoming air pushes out the burnt gases while passing over the deflector. This process of sweeping out the burnt gases is called scavenging. • The piston moves upwards i.e. from B.D.C. to T.D.C. it first closes the transfer port and a little later the exhaust port. • Before the end of compression stroke, the fuel is injected and the atomized fuel burns due to high temperature of air called auto ignition. • The resulted hot gases will again expand, thus completing a cycle.

  14. INTAKE STROKE • Piston moves from TDC to BDC • creating vacuum in the cylinder • Intake valve opens allowing only • air to enter the cylinder and • exhaust valve remains closed

  15. COMPRESSION STROKE • Both valves stay closed • Piston moves from BDC to TDC, • compressing air to 22:1 • Compressing the air to this extent • increases the temperature inside the • cylinder to above 1000 degree F

  16. POWER STROKE • Both valves stay closed. • When the piston is at the end of compression stroke(TDC) the injector sprays a mist of diesel fuel into the cylinder. • Expanding gases push the piston from TDC to BDC

  17. EXHAUST STROKE • Piston moves from BDC to TDC • Exhaust valve opens and the exhaust gases escape • Intake valve remains closed

  18. Four Strokes of Diesel Engine • The working of a diesel engine is similar to petrol engines working on Otto cycle except that in case of C.I. engines the air is only drawn during its suction stroke instead of mixture of fuel and air drawn in case of S.I. engines • In case of C.I. engines the fuel is injected into the cylinder before the end of compression stroke under very high pressures. • The compression ratio used for diesel engines various from 14 to 24.

  19. Comparison between two stroke and four stroke engine

  20. THANK YOU !!!!!!!