Hydrogen enrichment effects on the second law analysis of natural and landfill gas combustion in engine cylinders

Rakopoulos, CD; Kyritsis, DC

dc.contributor.author	Rakopoulos, CD	en
dc.contributor.author	Kyritsis, DC	en
dc.date.accessioned	2014-03-01T01:24:29Z
dc.date.available	2014-03-01T01:24:29Z
dc.date.issued	2006	en
dc.identifier.issn	0360-3199	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/17286
dc.subject	second law analysis	en
dc.subject	hydrogen enrichment	en
dc.subject	natural gas	en
dc.subject	landfill gas	en
dc.subject	combustion engines	en
dc.subject.classification	Chemistry, Physical	en
dc.subject.classification	Energy & Fuels	en
dc.subject.classification	Environmental Sciences	en
dc.subject.classification	Physics, Atomic, Molecular & Chemical	en
dc.subject.other	TURBOCHARGED DIESEL-ENGINE	en
dc.subject.other	2ND LAW ANALYSIS	en
dc.subject.other	FUEL-CELLS	en
dc.subject.other	OPERATION	en
dc.subject.other	BALANCES	en
dc.subject.other	EXERGY	en
dc.subject.other	IRREVERSIBILITIES	en
dc.subject.other	SIMULATION	en
dc.subject.other	ENERGY	en
dc.subject.other	HEAT	en
dc.title	Hydrogen enrichment effects on the second law analysis of natural and landfill gas combustion in engine cylinders	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.ijhydene.2005.11.002	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.ijhydene.2005.11.002	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	The availability (exergy) balance during combustion of hydrogen-enriched natural and landfill gas, which are used as fuels in combustion engine cylinders, is studied computationally using a zero-dimensional model of the closed part of the cycle. The main focus is on the demonstration of a fundamental difference in the generation of irreversibility during combustion between hydrogen and hydrocarbons. This difference relates to the mechanisms of entropy generation during the oxidation reaction of the two fuels and yields the particularly attractive characteristic of a monotonic decrease in combustion irreversibility with increasing hydrogen content of the fuel, for mole fractions of hydrogen smaller than 10%. This reduction in combustion irreversibility is reflected in an increase in second law efficiency with increasing proportions of hydrogen. The exhaust gas availability at the end of the closed part of the cycle was found to have a local maximum for a hydrogen mole fraction of the order of 5%. These trends with respect to hydrogen also apply when the fuel is diluted with a significant amount of CO2 (of the order of 40%, as for example in the case for landfill gas), although the absolute value of each of the terms of the availability balance is affected strongly by the dilution. (c) 2005 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	INTERNATIONAL JOURNAL OF HYDROGEN ENERGY	en
dc.identifier.doi	10.1016/j.ijhydene.2005.11.002	en
dc.identifier.isi	ISI:000239101200017	en
dc.identifier.volume	31	en
dc.identifier.issue	10	en
dc.identifier.spage	1384	en
dc.identifier.epage	1393	en