- Both these cycle are air standard cycles of automobile engines.
- Otto cycle is used for petrol or spark ignition engine.
- Diesel cycle is used for diesel or compression ignition engine.
The main difference
between Otto cycle and Diesel cycle is that in Otto cycle heat addition takes place
at constant volume and in diesel cycle heat addition takes places at constant pressure. This is the major
difference between Otto cycle and diesel cycle. There are many other
differences which are described below.
Sl.No
|
Otto
Cycle
|
Diesel
Cycle
|
1
|
It is ideal cycle
for petrol engine.
|
It is ideal cycle
for diesel engine.
|
2
|
Otto cycle has
higher thermal efficiency.
|
It has lower
thermal efficiency.
|
3
|
This cycle has
comparatively low compression ratio. It compresses the mixture up to 11:1
ratio.
|
Diesel cycle has
high compression ratio. It compresses the mixture up to 22.1 ratios.
|
4
|
Otto cycle engine
used spark plunge to ignite the air fuel mixture.
|
Fuel
automatically ignites due to high temperature of compressed gas.
|
5
|
Heat addition
takes place at constant volume.
|
Heat addition
takes place at constant pressure.
|
6
|
Air fuel mixture
drawn into the cylinder during intake stroke.
|
Once air is drawn into intake stroke. Fuel is
injected after end or compression stroke by an injector.
|
7
|