OTTO CYCLE
Objective: Explain what is the Otto
cycle, how it works and application
By: Jonathan Tang
Otto Cycle
Also known as 4 stroke cycle in technical
terms
 A Cycle used in internal combustion
engines
 The first such engine was built by the
German engineer Otto in 1861

4 Strokes of the Otto Cycle
Cycle contains 4 strokes
1)Intake stroke
2)Compression stroke
3)Power stroke
4)Exhaust stroke


Intake stroke
- Intake valve opens and a
mixture of air and fuel with a
relatively low pressure (near
atmosphere) is drawn into the
cylinder. As piston begin to move
back up, intake valve closes.

Compression stroke
-With both valve closed, the fuel-air
mixture is compressed by the
upward movement of piston,
causing a rise in pressure.

Power Stroke
-The mixture is ignited by spark
plugs with the piston staying nearly
fixed, leading to a rise in pressure
and temperature.
-The hot gas is then allowed to do
work by pushing the piston back.

Exhaust Stroke
-The exhaust valve is opened and
some exhaust escapes with the
piston remaining fixed.
-The piston forces the remaining
exhaust to escape. The exhaust
valve is then closed, the intake valve
opened, and the cycle repeats
Applications


Common cycle used in internal combustion
engines.
Otto cycle (4 stroke) engines are commonly
used in most cars and trucks today
Conclusion:
 Otto cycle engines are most commonly used
compare to 2 stroke or Wankel (rotary) engine
References




http://en.wikipedia.org/wiki/Otto_cycle
http://scienceworld.wolfram.com/physics/OttoCycle.html
http://www.keveney.com/otto.html
http://www.grc.nasa.gov/WWW/K12/airplane/engopt.html