Performance optimization of an air-standard irreversible dual-atkinson cycle engine based on the ecological coefficient of performance criterion.

Guven Gonca,Bahri Sahin

doi:10.1155/2014/815787

Abstract

This paper presents an ecological performance analysis and optimization for an air-standard irreversible Dual-Atkinson cycle (DAC) based on the ecological coefficient of performance (ECOP) criterion which includes internal irreversibilities, heat leak, and finite-rate of heat transfer. A comprehensive numerical analysis has been realized so as to investigate the global and optimal performances of the cycle. The results obtained based on the ECOP criterion are compared with a different ecological function which is named as the ecologic objective-function and with the maximum power output conditions. The results have been attained introducing the compression ratio, cut-off ratio, pressure ratio, Atkinson cycle ratio, source temperature ratio, and internal irreversibility parameter. The change of cycle performance with respect to these parameters is investigated and graphically presented.

Highlights

In the recent years, the studies related to engine research focused on reducing pollutant emissions, NOx, released from internal combustion engines owing to environmental regulations and restrictions
This study presents a thermoecological performance analysis based on the ecological coefficient of performance (ECOP), the ecological objective-function (E), and the maximum power output conditions for an irreversible Dual-Atkinson cycle (DAC) engine
Comprehensive computations are performed evaluating compression ratio (r) in order to compare the consequences of DAC depending on different performance parameters such as maximum ECOP, MEF, and maximum power (MP) conditions

Summary

Introduction

The studies related to engine research focused on reducing pollutant emissions, NOx, released from internal combustion engines owing to environmental regulations and restrictions. Ust et al [37,38,39,40] carried out performance analyses and optimizations for irreversible Carnot heat engine [37] and Brayton heat engine [38,39,40] considering losses owing to heat leak, heat transfer, and internal irreversibilities, based on ecological coefficient of performance (ECOP) function. Ust [43] carried out a performance analysis based on ECOP criterion for irreversible air refrigeration cycles considering irreversibilities because of finite-rate heat transfer, heat leakage, and internal dissipations. This study presents a thermoecological performance analysis based on the ECOP, the ecological objective-function (E), and the maximum power output conditions for an irreversible DAC engine. This study could be used as a guideline by real engine designers to obtain maximum ecological performance for DAC engines

Theoretical Analysis of DAC

Results and Discussion

Conclusion

E: Ecological performance function