Criteria S.I. Engine (Petrol or Spark Ignition Engine) C.I. Engine (Diesel or Compression Ignition Engine) Working Cycle Works on Otto Cycle or Constant Volume Cycle. Works on Diesel Cycle. Mixture During Suction Stroke Takes a mixture of air and petrol during the suction stroke. Takes only air during the suction stroke. Fuel Used Uses petrol as fuel. Uses diesel as fuel. Compression Ratio Has a compression ratio that varies from 6 to 10. Has a compression ratio that varies from 16 to 20. Engine Weight and Cost S.I. engines are lighter and cheaper. C.I. engines are heavier and costlier. Initial Cost Initial cost is lower compared to C.I. engines. Initial cost is high due to high compression ratio. Starting Starting is easy. Starting is difficult, especially in cold conditions. ...
Q-2 Ten Parts of an Internal Combustion Engine
1. Cylinder:-It is a cylindrical vessel where the piston reciprocates. The cylinder is covered with a cylinder head on one side and is open toward the crank on the other side. It is a good conductor of heat and is made of durable materials.
2. Cylinder Head:-It encloses one end of the cylinder and contains the inlet and exhaust valves for the entry of fuel and exit of exhaust gases.
3. Piston:-The piston fits into the cylinder. Its main functions are to compress the fuel during the compression stroke and to transmit the force exerted by gases to the connecting rod.
4. Piston Ring: - These rings are inserted into the circumferential grooves provided on the outer surface of the piston to provide a tight seal between the piston and cylinder wall, preventing leakage of high-pressure gas.
5. Gudgeon Pin:- It connects the piston to the small end of the connecting rod.
6.Connecting Rod:- It connects the piston and crank. Its function is to convert the reciprocating motion of the piston into the rotary motion of the crankshaft.
7.Crank and Crankshaft:- The crank is held with the crankshaft together with the help of a key. It is supported in the bearing and has a flywheel to decrease fluctuations in turning moment.
8. Valve:- Used to open and close passages. Each engine cylinder has at least two valves, i.e., inlet and exhaust.
9. Spark Plug:-Used in spark-ignition (SI) engines to initiate combustion. It is usually located on the cylinder head.
10. Carburettor:-Used in SI engines to mix petrol and air in proper proportions and supply the mixture to the cylinder at the proper time.
11. Flywheel:- Acts as an energy reservoir. It is made up of cast iron.
12.Camshaft:- It Controls the opening and closing of valves at the proper time. It is made of alloy or medium carbon steel.
13. Fuel Injector:- Supplies fuel to the cylinder in the form of fine spray.
14. Fuel Injector Pump:- Supplies fuel to the fuel injector at a very high pressure to the fuel injector.