Effect of mean piston speed and residual gas fraction on performance of a four-stroke irreversible Otto cycle engine

Abstract

In this study, a four-stroke irreversible Otto cycle model was constructed using the finite time thermodynamics to investigate the effect of the mean piston speed and the residual gas fraction on the cycle (or engine) performance. Fuel consumption was taken as a function of mean piston speed, and initial cycle temperature was considered as a function of residual gas fraction. It has been assumed that the specific heat does not change depending on the temperature. A detailed numerical example study has been made to see the effect of the mean piston speed and the residual gas fraction on engine performance. As a result of the numerical example made, the cycle thermal efficiency and the dimensionless power output were observed with the increase of the residual gas amount and the mean piston speed. We think that the results obtained are especially important for engine designers.

Keywords

• Otto cycle modeling,performance,mean piston speed,residual gas fraction

References

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