Multidimensional modeling of the effect of Exhaust Gas Recirculation (EGR) on exergy terms in an HCCI engine fueled with a mixture of natural gas and diesel. (15th November 2015)

• Record Type: Journal Article
• Authors: Jafarmadar, Samad; Nemati, Peyman; Khodaie, Rana
• Is Part Of: Energy conversion and management. Volume 105(2016)
• Page Start: 498
• Page End: 508
• Publication Date: 2015-11-15
• Subjects: Exergy -- HCCI -- Irreversibly -- Multidimensional modeling -- EGR; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2015.08.014
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: The exergy efficiency decreases by 41.3%. The irreversibility increases by 46.80%. The cumulative heat loss exergy decreases by 68.10%. The cumulative work exergy decreases by 63.4%. The exhaust losses exergy increases by 28.79%. Abstract: One of the most important issues in HCCI engines is auto-ignition timing control. EGR introduction into intake charge can be a method to control combustion phasing and its duration. In the current study, a FORTRAN-based code which includes 10 species (O2, N2, H2 O, CO2, CO, H2, OH, O, N, NO) associated with combustion products was employed to study the exergy analysis in a dual fuel (natural gas + diesel) HCCI engine at four EGR (exhaust gas recirculation) mass fractions (0%, 10%, 20%, and 30%) while the diesel fuel amount was held constant. In order to achieve this task, a 3-D CFD code was employed to model the energy balance during a closed cycle of running engine simulation. Moreover, an efficient Extend Coherent Flame Model-Three Zone model (ECFM-3Z) method was employed to analyze the combustion process. With crank positions at different EGR mass fractions, the exergy terms were identified and calculated separately. It was found that as EGR mass fraction increased from 0% to 30% (in 10% increment steps), exergy efficiency decreased from 48.9% to 28.7%. Furthermore, with the change in EGR mass fraction, the cumulative heat loss exergy decreased from 10.1% to 5.64% of mixture fuels chemical exergy.