Four Stroke Cycle 41453 Essay Example

gases used to generate power by converting reciprocating motion into rotating motion. These engines can be categorized as either reciprocating or rotary engines. Reciprocating engines are more common and have combustion occurring in a cylinder with a moving piston. In contrast, rotary engines have fewer parts and utilize a disk-based system. Moreover, there are two kinds of internal combustion engines: spark ignition and compression ignition.

Comprehending the Four Stroke Cycle

The Four Stroke Cycle is commonly utilized in internal combustion engines for automotive and industrial applications. It encompasses various piston movements. In a four-stroke engine, each piston undergoes four movements: downward, upward, downward, and upward. The initial downward movement allows air to enter the cylinder, followed by an upward movement for compression. The subsequent downward movement represents the power stroke, while the second upward movement expels the gases generated during combustion. This engine type necessitates exhaust and air-intake valves. The Otto cycle employs four strokes or piston movements within a cylinder to complete one combustion cycle in a piston engine. These strokes include:

1. The Intake Stroke, also known as the Induction Stroke.

2. During the compression stroke, the volume inside the cylinder decreases.

The Combustion Stroke refers to the Ignition, Power, or Expansion Stroke.

4. The Exhaust Stroke

The four-stroke cycle begins when the piston reaches its highest point. During the first downward stroke, a mixture of fuel and air enters the cylinder through the inlet valve, which then closes. The second upward stroke compresses the fuel-air mixture within the cylinder. This mixture is ignited near the top of the compression stroke, usually by spark plugs in a gasoline or Otto cycle engine. The ignition causes an explosion in the burning

gases, pushing the piston down for the third stroke, also known as the power stroke.

The fourth upward stroke, known as the Exhaust Stroke, expels burned gases from the cylinder through an open exhaust valve and out via an exhaust pipe. In a piston engine, each piston must move back and forth twice and pause four times to complete one cycle. A piston engine produces one power stroke every other time a piston moves down its cylinder.

Comparison between Gasoline Engine and Diesel Engine

Rudolph Diesel, a German engineer, invented the diesel engine in 1892. This engine is specifically designed for heavy-duty tasks and is well-known for its superior power compared to gasoline engines. It functions by using oil as its fuel source. Diesel engines are commonly used in heavy machinery, locomotives, ships, as well as vehicles like tractors, large buses, and massive freight trucks for heavy road-building equipment.

There are two main variations of diesel engines: the four-stroke engine and the two-stroke engine. The distinguishing factors between these types lie in the number of piston strokes required to complete a cycle that includes fresh-air intake, air compression, power generation, and exhaust release.

The Gasoline Engine and Diesel Engine differ in their ignition methods. The diesel engine utilizes compression-ignition, where air is compressed in the cylinders to raise temperature. Fuel is then injected into the hot, compressed air and ignites explosively. In contrast, the gasoline engine relies on a spark plug located at the top of the compression stroke for ignition. Consequently, the main difference between these engines lies in their respective ignition processes.