The diesel engine works on the diesel cycle. It is easy to start, lighter and cheaper, It has a high running cost and low maintenance cost. The petrol engine works on the Otto cycle. And a diesel engine draws only air during the suction stroke. The main difference between a petrol engine and a diesel engine is a petrol engine draws a mixture of petrol and air during the suction stroke. Difference Between Petrol Engine and Diesel Engine The crankshaft, in turn, drives the machine connected to it.Įxhaust StrokeIn this stroke, the burnt gases are exhausted from the engine cylinder, so as to make space available for the fresh fuel vapour. The rise of the pressure pushes the piston with a high force and rotates the crankshaft. when the fuel is burned suddenly raise the pressure, due to the expansion of the combustion products in the engine cylinder. Suction StrokeIn this stroke the fuel vapour, in the correct proportion, is supplied to the engine cylinder.Ĭompression StrokeIn this stroke, the fuel vapour is compressed in the engine cylinder.Įxpansion StrokeIn this stroke, the fuel vapour burn by the spark plug is provided on the top of the engine cylinder. The IC engine has four steps to complete one cycle as follows: We know that when the engine returns back to the stroke where it starts we say that one cycle has been completed. In internal combustion engines, when the IC engine is working continuously, we may consider a cycle starting from any strokes. The IC engine has a higher thermal efficiency than the thermal efficiency of EC engines. In IC engines (internal combustion engines) the combustion of takes place inside the cylinder, therefore the thermal energy of the fuel is directly converted into mechanical work. Working Principle of Internal Combustion Engines
Internal combustion engines – If the combustion fuel takes place inside the engine cylinder, it is an internal combustion engine. Ex: Steam turbine, Gas Turbine, Steam Turbine etc. External combustion engines – If the combustion of fuel place outside the engine cylinder, it is an external combustion engine.