Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine

To mitigate the increasing concentration of carbon dioxide in the atmosphere, energy production processes must change from fossil to renewable resources. Bioenergy utilization from agricultural residues can be a step towards achieving this goal. Syngas (fuel obtained from biomass gasification) has b...

Full description

Bibliographic Details
Main Authors: S.D. Martinez-Boggio, S.S. Merola, P. Teixeira Lacava, A. Irimescu, P.L. Curto-Risso
Format: Article
Language:English
Published: MDPI AG 2019-04-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/12/8/1566
_version_ 1798035449345736704
author S.D. Martinez-Boggio
S.S. Merola
P. Teixeira Lacava
A. Irimescu
P.L. Curto-Risso
author_facet S.D. Martinez-Boggio
S.S. Merola
P. Teixeira Lacava
A. Irimescu
P.L. Curto-Risso
author_sort S.D. Martinez-Boggio
collection DOAJ
description To mitigate the increasing concentration of carbon dioxide in the atmosphere, energy production processes must change from fossil to renewable resources. Bioenergy utilization from agricultural residues can be a step towards achieving this goal. Syngas (fuel obtained from biomass gasification) has been proved to have the potential of replacing fossil fuels in stationary internal combustion engines (ICEs). The processes associated with switching from traditional fuels to alternatives have always led to intense research efforts in order to have a broad understanding of the behavior of the engine in all operating conditions. In particular, attention needs to be focused on fuels containing relatively high concentrations of hydrogen, due to its faster propagation speed with respect to traditional fossil energy sources. Therefore, a combustion study was performed in a research optical SI engine, for a comparison between a well-established fuel such as methane (the main component of natural gas) and syngas. The main goal of this work is to study the effect of inert gases in the fuel mixture and that of air dilution during lean fuelling. Thus, two pure syngas blends (mixtures of CO and H<sub>2</sub>) and their respective diluted mixtures (CO and H<sub>2</sub> with 50vol% of inert gases, CO<sub>2</sub> and N<sub>2</sub>) were tested in several air-fuel ratios (stoichiometric to lean burn conditions). Initially, the combustion process was studied in detail by traditional thermodynamic analysis and then optical diagnostics were applied thanks to the optical access through the piston crown. Specifically, images were taken in the UV-visible spectrum of the entire cycle to follow the propagation of the flame front. The results show that hydrogen promotes flame propagation and reduces its distortion, as well as resulting in flames evolving closer to the spark plug. All syngas blends show a stable combustion process, even in conditions of high air and fuel dilution. In the leanest case, real syngas mixtures present a decrease in terms of performance due to significant reduction in volumetric efficiency. However, this condition strongly decreases pollutant emissions, with nitrogen oxide (NO<sub>x</sub>) concentrations almost negligible.
first_indexed 2024-04-11T20:57:26Z
format Article
id doaj.art-86e40709a1b44e15927d8e58576e53b4
institution Directory Open Access Journal
issn 1996-1073
language English
last_indexed 2024-04-11T20:57:26Z
publishDate 2019-04-01
publisher MDPI AG
record_format Article
series Energies
spelling doaj.art-86e40709a1b44e15927d8e58576e53b42022-12-22T04:03:37ZengMDPI AGEnergies1996-10732019-04-01128156610.3390/en12081566en12081566Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI EngineS.D. Martinez-Boggio0S.S. Merola1P. Teixeira Lacava2A. Irimescu3P.L. Curto-Risso4Instituto de Mecánica y Producción Industrial, Universidad de La República, Montevideo 11300, UruguayIstituto Motori, Consiglio Nazionale delle Ricerche, 80125 Napoli, ItalyInstituto Tecnológico de Aeronáutica, São Jose dos Campos 12228-900, BrazilIstituto Motori, Consiglio Nazionale delle Ricerche, 80125 Napoli, ItalyInstituto de Mecánica y Producción Industrial, Universidad de La República, Montevideo 11300, UruguayTo mitigate the increasing concentration of carbon dioxide in the atmosphere, energy production processes must change from fossil to renewable resources. Bioenergy utilization from agricultural residues can be a step towards achieving this goal. Syngas (fuel obtained from biomass gasification) has been proved to have the potential of replacing fossil fuels in stationary internal combustion engines (ICEs). The processes associated with switching from traditional fuels to alternatives have always led to intense research efforts in order to have a broad understanding of the behavior of the engine in all operating conditions. In particular, attention needs to be focused on fuels containing relatively high concentrations of hydrogen, due to its faster propagation speed with respect to traditional fossil energy sources. Therefore, a combustion study was performed in a research optical SI engine, for a comparison between a well-established fuel such as methane (the main component of natural gas) and syngas. The main goal of this work is to study the effect of inert gases in the fuel mixture and that of air dilution during lean fuelling. Thus, two pure syngas blends (mixtures of CO and H<sub>2</sub>) and their respective diluted mixtures (CO and H<sub>2</sub> with 50vol% of inert gases, CO<sub>2</sub> and N<sub>2</sub>) were tested in several air-fuel ratios (stoichiometric to lean burn conditions). Initially, the combustion process was studied in detail by traditional thermodynamic analysis and then optical diagnostics were applied thanks to the optical access through the piston crown. Specifically, images were taken in the UV-visible spectrum of the entire cycle to follow the propagation of the flame front. The results show that hydrogen promotes flame propagation and reduces its distortion, as well as resulting in flames evolving closer to the spark plug. All syngas blends show a stable combustion process, even in conditions of high air and fuel dilution. In the leanest case, real syngas mixtures present a decrease in terms of performance due to significant reduction in volumetric efficiency. However, this condition strongly decreases pollutant emissions, with nitrogen oxide (NO<sub>x</sub>) concentrations almost negligible.https://www.mdpi.com/1996-1073/12/8/1566syngasoptical techniquesSI engineselectricity generationlean combustion
spellingShingle S.D. Martinez-Boggio
S.S. Merola
P. Teixeira Lacava
A. Irimescu
P.L. Curto-Risso
Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine
Energies
syngas
optical techniques
SI engines
electricity generation
lean combustion
title Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine
title_full Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine
title_fullStr Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine
title_full_unstemmed Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine
title_short Effect of Fuel and Air Dilution on Syngas Combustion in an Optical SI Engine
title_sort effect of fuel and air dilution on syngas combustion in an optical si engine
topic syngas
optical techniques
SI engines
electricity generation
lean combustion
url https://www.mdpi.com/1996-1073/12/8/1566
work_keys_str_mv AT sdmartinezboggio effectoffuelandairdilutiononsyngascombustioninanopticalsiengine
AT ssmerola effectoffuelandairdilutiononsyngascombustioninanopticalsiengine
AT pteixeiralacava effectoffuelandairdilutiononsyngascombustioninanopticalsiengine
AT airimescu effectoffuelandairdilutiononsyngascombustioninanopticalsiengine
AT plcurtorisso effectoffuelandairdilutiononsyngascombustioninanopticalsiengine