internal combustion engine animation 4 stroke

Four stroke Compression Ignition (CI) Engine

At this time the exhaust valve is open (process 4-1) which results in the evacuation of all burnt gases from the cylinder and a sudden drop of pressure inside the cylinder. It produces considerable amount of pressure.īecause of the high amount of pressure generated due to combustion, piston again starts moving from top to bottom dead center (both inlet and exhaust valves are closed). This is called power stroke (from 3-4).īoth temperature and pressure decrease during the expansion stroke.Īfter the completion of power stroke, the piston starts moving from bottom dead center to top dead center. 2000-degree Celsius temperature is generated). In the combustion process the chemical energy of the fuel gets converted into the thermal energy of fuel (approx. In ideal engine it is supposed that the combustion takes place instantly and it is a constant volume (process 2-3). When the piston reaches top dead center, a spark is ignited to initiate the combustion process. The charge inside the cylinder is compressed when piston starts to move from bottom dead center to top dead center (process 1-2). At this time both inlet and exhaust valves are in closed position. When the piston reaches bottom dead center the inlet valve gets closed. SI engine works on Otto cycle, below is the diagram of Otto cycleĪs shown in diagram the suction stroke starts when the piston is at top dead center and about to move downward the inlet valve is opened and the exhaust valve is closed simultaneously (refer animation above). Due to vacuum created by downward movement of piston fuel-air mixture (charge) is sucked inside the cylinder. In four stroke SI engine the combustion process starts with the help of an externally produced spark (generated by spark plug), hence it is called a spark ignition engine.

Here we will discuss both four stroke SI & CI engines in detail. Otto whereas CI engines were invented by Rudolf Diesel. The credit of invention of SI engines goes to Nicolaus A. Generally Gasoline is used as a fuel in SI engines and Diesel is used as a fuel in CI engines. the type of fuel used and the method used to ignite the fuel. In this animation blue color represents fresh charge and brown color represents exhaust gases.įour stroke engines require two rotations of crank shaft to complete one cycle of operation, unlike two stroke engine which requires only one.īoth four stroke spark ignition (SI) and compression ignition (CI) engines has many things in common but they are fundamentally different, for e.g. This animation shows all the five operations mentioned above in the four strokes.

Internal combustion engine animation 4 stroke