describe the steps in a 4-stroke in gasoline engine?

Answer 1

The four-stroke cycle of an internal combustion engine is the cycle most commonly used for automotive and industrial purposes today (cars and trucks, electrical generators, etc). The Thermodynamics cycles used in internal combustion reciprocating engines are the Otto Cycle (the ideal cycle for spark-ignition engines) and the Diesel Cycle (the ideal cycle for compression-ignition engines). The Otto Cycle consists of adiabatic compression, heat addition at constant volume, adiabatic expansion and rejection of heat at constant volume.

The Otto cycle is characterized by four strokes, or straight movements alternately, back and forth, of a piston inside a cylinder:

intake (induction) stroke
compression stroke
power (combustion) stroke
exhaust stroke
The cycle begins at top dead center (TDC), when the piston is furthest away from the crankshaft. On the first stroke (intake) of the piston, a mixture of fuel and air is drawn into the cylinder through the intake (inlet) port. The intake (inlet) valve (or valves) then close(s) and the following stroke (compression) compresses the fuel-air mixture.


Four-stroke cycle (or Otto cycle)The air-fuel mixture is then ignited, usually by a spark plug for a gasoline or Otto cycle engine or by the heat and pressure of compression for a Diesel cycle or compression ignition engine, at approximately the top of the compression stroke. The resulting expansion of burning gases then forces the piston downward for the third stroke (power) and the fourth and final stroke (exhaust) evacuates the spent exhaust gases from the cylinder past the then-open exhaust valve or valves, through the exhaust port.

Answer 2

1. Cam rotates, opens intake valve, crackshaft rotates, pulling piston down, drawing fuel/air mixture into cylinder.

2. Cam continutes rotating, intake valve closes, crankshaft rotates, pushing piston up in cylinder, compressing fuel/air mixture.

3. Spark plug fires, igniting mixture, which pushes piston down, giving a momentum impulse to the crankshaft and flywheel rotation.

4. Momentum of flywheel and crankshaft pushes piston up in cylinder. Cam rotates, opening exhaust valve. Piston pushes exhaust gases out of cylinder.

Answer 3

Intake
A mixture of fuel and air is drawn into the cylinder

Compression
The fuel-air mix is compressed

Combustion
The fuel-air mix is ignited and burns

Exhaust
The burned mixture is expelled from the cylinder.

Hope that helps.


Doug

Answer 4

first step is the fuel introduction,then compression &burning then an expansion &lastly compression& expulsion of the burnt fuel & air

Answer 5

along with these answers, if you want to get mathematical, you could look at thermodynamics and the carnot cycle.