Reciprocating engine

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What is meant by I.C. engine?
In this type of engine, combustion of fuel takes place within the cylinder. This type of engine includes gas engine, petrol engines and diesel engines. These are generally used for road vehicles, locomotives, and aircraft and for other industrial applications.

Write the classification of I.C. engines.
Based on ignition:
Spark ignition
Compression ignition
Based on fuel:
Petrol engine
Diesel engine
Based on cooling system:
Air cooled
  Water cooled

 What is reciprocating engine?
 An engine in which reciprocating motion of piston creates mechanical    energy, necessary to do a work.

   What are the types of fuel ignition in reciprocating engine?
   Spark ignition- Uses a spark plug to ignite fuel
  Compression ignition- Compression will be done excessively so that when       fuel enters it can automatically ignite.

    Note: Whenever we do compression, temperature increases.

What is meant by Top dead centre?
This refers to the position of the crankshaft when the piston is in its top most position i.e., the position closest to the cylinder head.

What is meant by Bottom dead centre?
This refers to the position of the crankshaft when the piston is in its lowest position i.e., the position closest to the cylinder head.

Define stroke.
Stroke is defined as the distance traveled by the piston while moving from T.D.C to the B.D.C.

What is meant by clearance volume?
   The volume of cylinder above the piston when it is in the T.D.C. position is    referred to as Clearance volume (Vc).

 Say how a two stroke compression ignition type engine works?
Intake, compression, power and exhaust process occurs in just two strokes. Two stroke engines have a power stroke for each revolution of crankshaft. From the below figure, you can easily grasp the techniques of how it works.
The forced air is taken inside the cylinder which is again compressed to attain auto ignition as soon as fuel is injected from fuel injector. The combustion starts and lot of pressure develops and drives the piston to bottom dead centre. When piston starts to go to Top, Exhaust valve opens for certain predefined time, so exhaust goes out. Now intake starts after exhaust closes. Cycle goes on like this.


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