Comparison Of Otto, Diesel and Dual Cycles

OTTO CYCLE :

* It consists of adiabatic and two constant volume processes.

* Compression ratio is equal to expansion ratio.

* Heat addition takes place at constant volume process.

* Compression ratio is less. It varies from 5 to 6.

* Efficiency depends on compression ratio only.

* Efficiency is more than diesel cycle for same compression.

* Heat rejected is less.

DIESEL CYCLE :

* It consists two adiabatic and two constant pressure processes.

* Compression ratio is not equal to expansion ratio.

* Heat addition takes place at constant pressure processes.

* Compression ratio is more. It varies from 12 to 18.

* Efficiency depends on cut off ratio and compression ratio.

* Efficiency is less than Otto cycle for same compression ratio.

* Heat rejected is more.

DUAL CYCLE :

* It consists of two adiabatic, two constant volume and one constant pressure processes.

* Compression ratio is not equal to expansion ratio.

* Heat addition takes place at both constant volume and constant pressure processes.

* Compression ratio lies between two.

* Efficiency depends on compression ratio, cut off ratio and pressure ratio.

* Efficiency lies between two.

* Heat rejected lies in between two.

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