Lecture 2 3/3/2012

Dr. walid Abdelghaffar

Dr. Walid Abdelghaffar







OTTO Cycle






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Otto Cycle Assignment 1

An Ideal Otto cycle has a compression ratio of

8. At the beginning of the compression

process, the air is at 100 kPa and 17C, and

800 kJ/kg of heat is transferred to air during the

constant volume heat addition processes.

Determine a) the maximum temperature and

pressure that occur during the cycle b) the net

work output c) the thermal efficiency, and d)

the mean effective pressure of the cycle.



For a SI engine, the intake air pressure and

temperature are 50 kPa and 300 K

respectively. The compression ratio is 10.

Assume the heat input of 2500 kJ/kg and =

1.3. If the fuel air cycle can be simplified to an

Otto cycle; calculate the net thermal efficiency,

the maximum temperature and pressure, and

the mean effective pressure.



For an Ideal Otto cycle, if the inlet pressure and

temperature are 1 bar and 25 C respectively.

The compression ratio is 9 and the maximum

temperature in the cycle can not exceed 2000

K. calculate a) the net work b)the cycle net

thermal efficiency and c) the MEP of the cycle.


Dr. walid Abdelghaffar

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Lecture 2 3/3/2012