A study of the operation of two stroke, four stroke Essay Example

to an expanding air-fuel mixture. The piston compresses while moving and is ignited via a spark plug. Exhaust is discharged through another opening in the cylinder. Unlike four-stroke engines that have mobile valves, every time a two-stroke engine's piston reaches its cycle peak, the spark plug ignites. As such, these engines undergo twice as many combustion cycles per rotation compared to others, granting them a higher power-to-size ratio. Notwithstanding, they have high fuel consumption rates and are significant contributors of oil pollution.

Contrarily, a four-stroke engine involves four phases: intake (induction), compression, ignition (combustion), and discharge of exhaust gases (exhaust). These stages transpire over two rotations for each operational cycle in any diesel-powered four-stroke engine.

In an engine, valves are typically governed by a camshaft. This camshaft is equipped with numerous cams along its length that trigger the opening of the valves at appropriate times during intake or exhaust strokes. The rotation speed of the camshaft is half that of the crankshaft. A tappet is located between the valve and cam, offering a surface for the cam to glide on and open up the valve. Different engines have varying placement and quantity of camshafts. Numerous engines employ overhead cams or even dual overhead cams as depicted in the illustration; here, through a flat tappet, cams directly regulate valves. This structure enables greater engine speeds since it establishes a shorter and direct route between the cam and valve which isn't easily extended. In some other engine designs, instead in the crankcase you'll find where they place theircamshafts with its movement relayed via push rod, rocker arms, and valve stems.