The connecting rod carries this force to the crankshaft which turns to move the vehicle. The heat of compressed air ignites the diesel fuel and generates high pressure which pushes down the piston. Power stroke:Īt the end of the compression stroke when the piston is at the top end of the cylinder a metered quantity of diesel is injected into the cylinder by the fuel injector. 11 Four stroke diesel engine The four strokes making up the operating cycle of a four stroke diesel engine are: 1. This consists of an engine driven air pump, commonly known a supercharger (fig 1.1.2).as Fig 1.1.2 Supercharger. To achieve this a scavenge blower is used. L stroke length (the distance between the TDC and BDC) cm or cm/10. In a two stroke engine, air has to be forced into the cylinder. At the end of compression stroke the piston is at top end of the cylinder. V c cylinder swept volume cm 3 (cc) or L. Both the inlet and exhaust valves do not open during any part of this stroke. Due to this compression, a high pressure and temperature generated inside the cylinder. This movement of the piston compresses the air into a small space between the top of the piston and cylinder head. Both valves are closed and the cylinder is sealed at that time.
What is Difference Between Petrol and Diesel Engine? Compression stroke:Īfter the piston passes the bottom end of the cylinder, it starts moving up.After it, inlet valve close and seal the upper end of the cylinder.] The inlet valve remains open until the piston reaches the lower end of the cylinder. At this time air at atmospheric pressure drawn inside the cylinder through the inlet valve by a pump.
In the suction stroke or intake stroke of diesel engine, the piston start moving from top end of the cylinder to bottom end of the cylinder and simultaneously inlet valve opens. These are suction stroke, compression stroke, expansion stroke, and exhaust stroke. In four stroke engine the piston move two time up and two time down and the crankshaft move two complete revolution to complete four piston cycle.
The piston is free to move only in an upward and downward direction. In IC engine, stroke is referred to the maximum distance travel by the piston in a single direction. The power generation process in four stroke diesel engine is also divided into four parts. Exhaust stroke: Working of Four Stroke Diesel Engine.