The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm

In this study, the effect of adding hydrogen to natural gas and EGR ratio was conducted on a diesel engine to investigate the engine performance and exhaust gases by AVL Fire multi-domain simulation software. For this investigation, a mixture of hydrogen fuel and natural gas replaced diesel fuel. Th...

Full description

Autores:
Zareei, Javad
Rohani, Abbas
Núñez Alvarez, José Ricardo
Tipo de recurso:
Article of journal
Fecha de publicación:
2022
Institución:
Corporación Universidad de la Costa
Repositorio:
REDICUC - Repositorio CUC
Idioma:
eng
OAI Identifier:
oai:repositorio.cuc.edu.co:11323/9329
Acceso en línea:
https://hdl.handle.net/11323/9329
https://doi.org/10.1016/j.ijhydene.2022.04.294.
https://repositorio.cuc.edu.co/
Palabra clave:
Exhaust gas recirculation
Diesel engine
Performance
Exhaust emissions
Multi-objective genetic algorithm (MOGA)
Cumulative heat release
Rights
embargoedAccess
License
Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)
id RCUC2_3c456b220c5e8707038b4892a9b67d25
oai_identifier_str oai:repositorio.cuc.edu.co:11323/9329
network_acronym_str RCUC2
network_name_str REDICUC - Repositorio CUC
repository_id_str
dc.title.eng.fl_str_mv The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
title The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
spellingShingle The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
Exhaust gas recirculation
Diesel engine
Performance
Exhaust emissions
Multi-objective genetic algorithm (MOGA)
Cumulative heat release
title_short The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
title_full The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
title_fullStr The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
title_full_unstemmed The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
title_sort The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm
dc.creator.fl_str_mv Zareei, Javad
Rohani, Abbas
Núñez Alvarez, José Ricardo
dc.contributor.author.spa.fl_str_mv Zareei, Javad
Rohani, Abbas
Núñez Alvarez, José Ricardo
dc.subject.proposal.eng.fl_str_mv Exhaust gas recirculation
Diesel engine
Performance
Exhaust emissions
Multi-objective genetic algorithm (MOGA)
Cumulative heat release
topic Exhaust gas recirculation
Diesel engine
Performance
Exhaust emissions
Multi-objective genetic algorithm (MOGA)
Cumulative heat release
description In this study, the effect of adding hydrogen to natural gas and EGR ratio was conducted on a diesel engine to investigate the engine performance and exhaust gases by AVL Fire multi-domain simulation software. For this investigation, a mixture of hydrogen fuel and natural gas replaced diesel fuel. The percentage of hydrogen in blend fuel changed from 0% to 40%. The compression ratio converted from 17:1 to 15:1. The EGR ratios were in three steps of 5%, 10%, and 15%, with different engine speeds from 1000 to 1800 RPM. The Gaussian process regression (GPR) was developed to model engine performance and exhaust emissions. The optimal values of EGR and the percentage of hydrogen in the blend of HCNG were extracted using a multi-objective genetic algorithm (MOGA). The results showed that by increasing EGR, thermal efficiency, the engine power, and specific fuel consumption decreased due to prolongation of combustion length while cumulative heat release increased but, its effect on cylinder pressure is insignificant. Adding hydrogen to natural gas increased the combustion temperature and, consequently NOx. While the amount of CO and HC decreased. The results of GPR and MOGA illustrated that at different engine speeds, the optimum values of EGR and HCNG were 6.35% and 31%, respectively.
publishDate 2022
dc.date.accessioned.none.fl_str_mv 2022-07-01T20:49:28Z
dc.date.available.none.fl_str_mv 2022-07-01T20:49:28Z
2023
dc.date.issued.none.fl_str_mv 2022
dc.type.spa.fl_str_mv Artículo de revista
dc.type.coar.fl_str_mv http://purl.org/coar/resource_type/c_2df8fbb1
dc.type.coarversion.fl_str_mv http://purl.org/coar/version/c_970fb48d4fbd8a85
dc.type.coar.spa.fl_str_mv http://purl.org/coar/resource_type/c_6501
dc.type.content.spa.fl_str_mv Text
dc.type.driver.spa.fl_str_mv info:eu-repo/semantics/article
dc.type.redcol.spa.fl_str_mv http://purl.org/redcol/resource_type/ART
format http://purl.org/coar/resource_type/c_6501
dc.identifier.citation.spa.fl_str_mv Javad Zareei, Abbas Rohani, José Ricardo Nuñez Alvarez, The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm, International Journal of Hydrogen Energy, Volume 47, Issue 50, 2022, Pages 21565-21581, ISSN 0360-3199, https://doi.org/10.1016/j.ijhydene.2022.04.294.
dc.identifier.issn.spa.fl_str_mv 0360-3199
dc.identifier.uri.spa.fl_str_mv https://hdl.handle.net/11323/9329
dc.identifier.url.spa.fl_str_mv https://doi.org/10.1016/j.ijhydene.2022.04.294.
dc.identifier.doi.spa.fl_str_mv 10.1016/j.ijhydene.2022.04.294.
dc.identifier.instname.spa.fl_str_mv Corporación Universidad de la Costa
dc.identifier.reponame.spa.fl_str_mv REDICUC - Repositorio CUC
dc.identifier.repourl.spa.fl_str_mv https://repositorio.cuc.edu.co/
identifier_str_mv Javad Zareei, Abbas Rohani, José Ricardo Nuñez Alvarez, The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm, International Journal of Hydrogen Energy, Volume 47, Issue 50, 2022, Pages 21565-21581, ISSN 0360-3199, https://doi.org/10.1016/j.ijhydene.2022.04.294.
0360-3199
10.1016/j.ijhydene.2022.04.294.
Corporación Universidad de la Costa
REDICUC - Repositorio CUC
url https://hdl.handle.net/11323/9329
https://doi.org/10.1016/j.ijhydene.2022.04.294.
https://repositorio.cuc.edu.co/
dc.language.iso.none.fl_str_mv eng
language eng
dc.relation.ispartofjournal.spa.fl_str_mv International Journal of Hydrogen Energy
dc.relation.references.spa.fl_str_mv [1] Lloyd AC, Cackette TA. Diesel engines: environmental impact and control. J Air Waste Manag Assoc 2001 Jun 1;51(6):809e47.
[2] Burtscher H. Physical characterization of particulate emissions from diesel engines: a review. J Aerosol Sci 2005 Jul 1;36(7):896e932.
[3] Chen H, Shi-Jin S, Jian-Xin W. Study on combustion characteristics and PM emission of diesel engines using estereethanolediesel blended fuels. Proc Combust Inst 2007 Jan 1;31(2):2981e9.
[4] Sathiyagnanam AP, Saravanan CG, Gopalakrishnan M. Hexanol-ethanol diesel blends on DI-diesel engine to study the combustion and emission. Proc WRI World Congr Comput Sci Inf Eng 2010 Jun 30;2:1e5.
[5] Azizb A. PM emission of diesel engines using ester-ethanoldiesel blended fuel. Procedia Eng 2013;53:530e5.
[6] Heydari-Maleney K, Taghizadeh-Alisaraei A, Ghobadian B, Abbaszadeh-Mayvan A. Analyzing and evaluation of carbon nanotubes additives to diesohol-B2 fuels on performance and emission of diesel engines. Fuel 2017 May 15;196:110e23.
[7] Ahmadipour S, Aghkhani MH, Zareei J. Investigation of injection timing and different fuels on the diesel engine performance and emissions. J Comput Appl Res Mech Eng 2020 Feb 1;9(2):385e96.
[8] Jamrozik A, Grab-Rogalinski K, Tutak W. Hydrogen effects on combustion stability, performance and emission of diesel engine. Int J Hydrogen Energy 2020 Jul 31;45(38):19936e47.
[9] Park H, Shim E, Lee J, Oh S, Kim C, Lee Y, Kang K. Largeesquish piston geometry and early pilot injection for high efficiency and low methane emission in natural gasediesel dual fuel engine at higheload operations. Fuel 2022 Jan 15;308:122015.
[10] Zareei J, Kakaee AH. Study and the effects of ignition timing on gasoline engine performance and emissions. European Transport Res Review 2013 Jun 1;5(2):109e16.
[11] Zareei J, Rohani A. Optimization and study of performance parameters in an engine fueled with hydrogen. Int J Hydrog Energy 2020 Jan 1;45(1):322e36.
[12] Bayramoglu K, Yılmaz S. Emission and performance estimation in hydrogen injection strategies on diesel engines. Int J Hydrog Energy 2021 Aug 18;46(57):29732e44.
[13] Raine RR, Stephenson J, Elder ST. Characteristics of diesel engines converted to spark ignition operation fuelled with natural gas. SAE Technical Paper; 1988 Feb 1.
[14] Mittal M, Donahue R, Winnie P, Gillette A. Exhaust emissions characteristics of a multi-cylinder 18.1-L diesel engine converted to fueled with natural gas and diesel pilot. J Energy Inst 2015 Aug 1;88(3):275e83.
[15] Luo H, Chang F, Jin Y, Ogata Y, Matsumura Y, Ichikawa T, Kim W, Nakashimada Y, Nishida K. Experimental investigation on performance of hydrogen additions in natural gas combustion combined with CO2. Int J Hydrog Energy 2021 Oct 11;46(70):34958e69.
[16] Liu J, Dumitrescu CE. Single and double Wiebe function combustion model for a heavy-duty diesel engine retrofitted to natural-gas spark-ignition. Appl Energy 2019 Aug 15;248:95e103.
[17] Likhanov VA, Rossokhin AV. The impact of the use of compressed natural gas in a car diesel engine on the formation and oxidation of soot particles. InIOP Conference Series: Mater Sci Eng 2020 Jan;734(1):12207. IOP Publishing.
[18] Liu J, Dumitrescu CE. Improved thermodynamic model for lean natural gas spark ignition in a diesel engine using a triple Wiebe function. J Energy Resour Technol 2020 Jun 1;142(6).
[19] Liu J, Dumitrescu CE. Investigation of multistage combustion inside a heavy-duty natural-gas spark-ignition engine using 3D CFD simulations and the wiebe-function combustion model. J Eng Gas Turbines Power 2020 Jan 1;142(10).
[20] Duan X, Liu Y, Liu J, Lai MC, Jansons M, Guo G, Zhang S, Tang Q. Experimental and numerical investigation of the effects of low-pressure, high-pressure and internal EGR configurations on the performance, combustion and emission characteristics in a hydrogen-enriched heavy-duty lean-burn natural gas SI engine. Energy Convers Manag 2019 Sep 1;195:1319e33.
[21] Chen H, He J, Zhong X. Engine combustion and emission fuelled with natural gas: a review. J Energy Inst 2019 Aug 1;92(4):1123e36.
[22] Ouchikh S, Lounici MS, Tarabet L, Loubar K, Tazerout M. Effect of natural gas enrichment with hydrogen on combustion characteristics of a dual fuel diesel engine. Int J Hydrog Energy 2019 May 21;44(26):13974e87.
[23] Lee CF, Pang Y, Wu H, Hernandez JJ, Zhang S, Liu F. The optical investigation of hydrogen enrichment effects on combustion and soot emission characteristics of CNG/diesel dual-fuel engine. Fuel 2020 Nov 15;280:118639.
[24] Hairuddin AA, Yusaf T, Wandel AP. A review of hydrogen and natural gas addition in diesel HCCI engines. Renew Sustain Energy Rev 2014 Apr 1;32:739e61.
[25] Das S, Kanth S, Das B, Debbarma S. Experimental evaluation of hydrogen enrichment in a dual-fueled CRDI diesel engine. Int J Hydrogen Energy 2022 Feb 9;47(20):11039e51.
[26] Ismael MA, Aziz AR, Mohammed SE, Baharom MB, Raheem AT, Ayandotun WB, et al. Experimental study on combustion stability and performance of hydrogen-enriched compressed natural gas of a free-piston linear generator. Int J Hydrogen Energy 2021 Nov 16;46(79):39536e47.
[27] Park C, Lee S, Kim C, Choi Y. A comparative study of lean burn and exhaust gas recirculation in an HCNG-fueled heavy-duty engine. Int J Hydrogen Energy 2017 Oct 12;42(41):26094e101.
[28] Liu YF, Liu B, Zeng K, Huang Z, Zhou L, Sun L. Performance and emission characteristics of a hydrogen-enriched compressed-natural-gas direct-injection spark ignition engine diluted with exhaust gas recirculation. Proc Inst Mech Eng - Part D J Automob Eng 2012 Jan;226(1):123e32.
[29] Zhao L, Wang D. Combined effects of cooled EGR and air dilution on butanolegasoline TGDI engine operation, efficiency, gaseous, and PM emissions. ACS Omega 2020 Mar 23;5(12):6556e65.
[30] Imran S, Korakianitis T, Shaukat R, Farooq M, Condoor S, Jayaram S. Experimentally tested performance and emissions advantages of using natural-gas and hydrogen fuel mixture with diesel and rapeseed methyl ester as pilot fuels. Appl Energy 2018 Nov 1;229:1260e8.
[31] Mehra RK, Duan H, Luo S, Rao A, Ma F. Experimental and artificial neural network (ANN) study of hydrogen enriched compressed natural gas (HCNG) engine under various ignition timings and excess air ratios. Appl Energy 2018 Oct 15;228:736e54.
[32] Aydın M, Uslu S, C¸ elik MB. Performance and emission prediction of a compression ignition engine fueled with biodiesel-diesel blends: a combined application of ANN and RSM based optimization. Fuel 2020 Jun 1;269:117472.
[33] Yaliwal VS, Banapurmath NR, Soudagar ME, Afzal A, Ahmadi P. Effect of manifold and port injection of hydrogen and exhaust gas recirculation (EGR) in dairy scum biodiesellow energy content gas-fueled CI engine operated on dual fuel mode. Int J Hydrog Energy 2022 Feb 1;47(10):6873e97.
[34] Uslu S. Optimization of diesel engine operating parameters fueled with palm oil-diesel blend: comparative evaluation between response surface methodology (RSM) and artificial neural network (ANN). Fuel 2020 Sep 15;276:117990.
[35] Hora TS, Agarwal AK. Effect of varying compression ratio on combustion, performance, and emissions of a hydrogen enriched compressed natural gas fuelled engine. J Nat Gas Sci Eng 2016 Apr 1;31:819e28.
[36] Verhelst S, Wallner T. Hydrogen-fueled internal combustion engines. Prog Energy Combust Sci 2009 Dec 1;35(6):490e527.
[37] Mabadi Rahimi H, Jazayeri SA, Ebrahimi M. Multi-objective optimization of a RCCI engine fueled with diesel fuel and natural gas enriched with hydrogen. Gas Processing Journal 2021 Jul 1;9(2):33e42.
[38] Balamurugan G, Gowthaman S. A review on split injection performances in DI diesel engine with different injection strategies and varying EGR using biodiesel as fuel. Mater Today Proc 2021 Feb 20.
[39] Balijepalli R, Kumar A, Rajak U, Elkotb MA, Alwetaishi M, Dasore A, Verma TN, Saleel CA, Afzal A. Numerical investigation of the effect of spray angle on emission characteristics of a diesel engine fueled with natural gas and diesel. Energy Rep 2021 Nov 1;7:7273e87.
[40] Bose PK, Maji D. An experimental investigation on engine performance and emissions of a single cylinder diesel engine using hydrogen as inducted fuel and diesel as injected fuel with exhaust gas recirculation. Int J Hydrog Energy 2009 Jun 1;34(11):4847e54.
[41] CFD A. Solver users guide [z]. AVL FIRE; 2013.
[42] Kostic O, Stefanovi c Z, Kosti c I. CFD modeling of supersonic airflow generated by 2D nozzle with and without an obstacle at the exit section. FME Transactions 2015;43(2):107e13.
[43] de Morais AM, Justino MA, Valente OS, de Morais Hanriot S, Sodre JR. Hydrogen impacts on performance and CO2 emissions from a diesel power generator. Int J Hydrog Energy 2013 May 30;38(16):6857e64.
[44] Agarwal D, Singh SK, Agarwal AK. Effect of Exhaust Gas Recirculation (EGR) on performance, emissions, deposits and durability of a constant speed compression ignition engine. Appl Energy 2011 Aug 1;88(8):2900e7.
[45] Williams CK, Rasmussen CE. Gaussian processes for machine learning. Cambridge, MA: MIT press; 2006.
[46] Arthur CK, Temeng VA, Ziggah YY. A Self-adaptive differential evolutionary extreme learning machine (SaDEELM): a novel approach to blast-induced ground vibration prediction. SN Appl Sci 2020 Nov;2(11):1e23.
[47] Snelson E, Ghahramani Z. Local and global sparse Gaussian process approximations. InArtificial Intelligence and Statistics 2007 Mar 11:524e31. PMLR.
[48] Arthur CK, Temeng VA, Ziggah YY. Soft computing-based technique as a predictive tool to estimate blast-induced ground vibration. J Sustain Mining 2019 Nov 1;18(4):287e96.
[49] Nocedal J, Wright SJ. Large-scale unconstrained optimization. Numerical Opt 2006:164e92.
[50] Anil R, Pereyra G, Passos A, Ormandi R, Dahl GE, Hinton GE. Large scale distributed neural network training through online distillation. arXiv preprint arXiv:1804.03235 2018 Apr 9.
[51] Li W, Liu Z, Wang Z, Dou H. Experimental and theoretical analysis of effects of atomic, diatomic and polyatomic inert gases in air and EGR on mixture properties, combustion, thermal efficiency and NOx emissions of a pilot-ignited NG engine. Energy Convers Manag 2015 Nov 15;105:1082e95.
[52] Hu E, Huang Z. Optimization on ignition timing and EGR ratio of a spark-ignition engine fuelled with natural gas-hydrogen blends. SAE Technical Paper; 2011 Apr 12.
[53] Zhou J, Guo Y, Huang Z, Wang C. A review and prospects of gas mixture containing hydrogen as vehicle fuel in China. Int J Hydrog Energy 2019 Nov 12;44(56):29776e84.
[54] Khodamrezaee F, Keshavarz A. Thermodynamic and experimental analysis of hydrogen addition to CNG in a spark ignition engine for emission reduction. Energy Sources, Part A Recovery, Util Environ Eff 2020 Apr 4:1e2.
[55] Park BY, Lee KH, Park J. Conceptual approach on feasible hydrogen contents for retrofit of CNG to HCNG under heavyduty spark ignition engine at low-to-middle speed ranges. Energies 2020 Jan;13(15):3861.
[56] Hao D, Mehra RK, Luo S, Nie Z, Ren X, Fanhua M. Experimental study of hydrogen enriched compressed natural gas (HCNG) engine and application of support vector machine (SVM) on prediction of engine performance at specific condition. Int J Hydrog Energy 2020 Feb 14;45(8):5309e25.
[57] Huang Z, Huang J, Luo J, Hu D, Yin Z. Performance enhancement and emission reduction of a diesel engine fueled with different biodiesel-diesel blending fuel based on the multi-parameter optimization theory. Fuel 2022 Apr 15;314:122753.
[58] Kumar BR, Saravanan S, Rana D, Anish V, Nagendran A. Effect of a sustainable biofuelen-octanoleon the combustion, performance and emissions of a DI diesel engine under naturally aspirated and exhaust gas recirculation (EGR) modes. Energy Convers Manag 2016 Jun 15;118:275e86.
[59] Kanth S, Ananad T, Debbarma S, Das B. Effect of fuel opening injection pressure and injection timing of hydrogen enriched rice bran biodiesel fuelled in CI engine. Int J Hydrog Energy 2021 Aug 13;46(56):28789e800.
[60] Zareei J, Rohani A, Mazari F, Mikkhailova MV. Numerical investigation of the effect of two-step injection (direct and port injection) of hydrogen blending and natural gas on engine performance and exhaust gas emissions. Energy 2021 Sep 15;231:120957.
[61] Lee S, Kim G, Bae C. Lean combustion of stratified hydrogen in a constant volume chamber. Fuel 2021 Oct 1;301:121045.
[62] Long Y, Li G, Zhang Z, Liang J. Application of reformed exhaust gas recirculation on marine LNG engines for NOx emission control. Fuel 2021 May 1;291:120114.
dc.relation.citationendpage.spa.fl_str_mv 21581
dc.relation.citationstartpage.spa.fl_str_mv 21565
dc.relation.citationissue.spa.fl_str_mv 50
dc.relation.citationvolume.spa.fl_str_mv 47
dc.rights.spa.fl_str_mv Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)
© 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
dc.rights.uri.spa.fl_str_mv https://creativecommons.org/licenses/by-nc-nd/4.0/
dc.rights.accessrights.spa.fl_str_mv info:eu-repo/semantics/embargoedAccess
dc.rights.coar.spa.fl_str_mv http://purl.org/coar/access_right/c_f1cf
rights_invalid_str_mv Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)
© 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
https://creativecommons.org/licenses/by-nc-nd/4.0/
http://purl.org/coar/access_right/c_f1cf
eu_rights_str_mv embargoedAccess
dc.format.extent.spa.fl_str_mv 17 páginas
dc.format.mimetype.spa.fl_str_mv application/pdf
dc.publisher.spa.fl_str_mv Elsevier Ltd.
dc.publisher.place.spa.fl_str_mv United Kingdom
institution Corporación Universidad de la Costa
dc.source.url.spa.fl_str_mv https://www.sciencedirect.com/science/article/pii/S0360319922019656#!
bitstream.url.fl_str_mv https://repositorio.cuc.edu.co/bitstreams/9ef85389-bfd5-4f28-97c7-2fd2c03b9ddd/download
https://repositorio.cuc.edu.co/bitstreams/2426e5ba-d6fd-4639-bd2d-f30b10fd02e7/download
https://repositorio.cuc.edu.co/bitstreams/1136fc1c-2333-4fe0-98d7-1ded9a415fc7/download
https://repositorio.cuc.edu.co/bitstreams/ebb8a0b2-0956-4366-afd5-6b8ffd957611/download
bitstream.checksum.fl_str_mv d4618ecba066f55baa161ef0c9ef514a
e30e9215131d99561d40d6b0abbe9bad
abcf3f4293439d2368d34b5114aa6093
43bb08f12b84c3dede622a218e8515d4
bitstream.checksumAlgorithm.fl_str_mv MD5
MD5
MD5
MD5
repository.name.fl_str_mv Repositorio de la Universidad de la Costa CUC
repository.mail.fl_str_mv repdigital@cuc.edu.co
_version_ 1811760759112204288
spelling Zareei, JavadRohani, AbbasNúñez Alvarez, José Ricardo2022-07-01T20:49:28Z20232022-07-01T20:49:28Z2022Javad Zareei, Abbas Rohani, José Ricardo Nuñez Alvarez, The effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithm, International Journal of Hydrogen Energy, Volume 47, Issue 50, 2022, Pages 21565-21581, ISSN 0360-3199, https://doi.org/10.1016/j.ijhydene.2022.04.294.0360-3199https://hdl.handle.net/11323/9329https://doi.org/10.1016/j.ijhydene.2022.04.294.10.1016/j.ijhydene.2022.04.294.Corporación Universidad de la CostaREDICUC - Repositorio CUChttps://repositorio.cuc.edu.co/In this study, the effect of adding hydrogen to natural gas and EGR ratio was conducted on a diesel engine to investigate the engine performance and exhaust gases by AVL Fire multi-domain simulation software. For this investigation, a mixture of hydrogen fuel and natural gas replaced diesel fuel. The percentage of hydrogen in blend fuel changed from 0% to 40%. The compression ratio converted from 17:1 to 15:1. The EGR ratios were in three steps of 5%, 10%, and 15%, with different engine speeds from 1000 to 1800 RPM. The Gaussian process regression (GPR) was developed to model engine performance and exhaust emissions. The optimal values of EGR and the percentage of hydrogen in the blend of HCNG were extracted using a multi-objective genetic algorithm (MOGA). The results showed that by increasing EGR, thermal efficiency, the engine power, and specific fuel consumption decreased due to prolongation of combustion length while cumulative heat release increased but, its effect on cylinder pressure is insignificant. Adding hydrogen to natural gas increased the combustion temperature and, consequently NOx. While the amount of CO and HC decreased. The results of GPR and MOGA illustrated that at different engine speeds, the optimum values of EGR and HCNG were 6.35% and 31%, respectively.17 páginasapplication/pdfengElsevier Ltd.United KingdomAtribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)© 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.https://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/embargoedAccesshttp://purl.org/coar/access_right/c_f1cfThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine by AVL fire multi-domain simulation, GPR model, and multi-objective genetic algorithmArtículo de revistahttp://purl.org/coar/resource_type/c_6501http://purl.org/coar/resource_type/c_2df8fbb1Textinfo:eu-repo/semantics/articlehttp://purl.org/redcol/resource_type/ARThttp://purl.org/coar/version/c_970fb48d4fbd8a85https://www.sciencedirect.com/science/article/pii/S0360319922019656#!International Journal of Hydrogen Energy[1] Lloyd AC, Cackette TA. Diesel engines: environmental impact and control. J Air Waste Manag Assoc 2001 Jun 1;51(6):809e47.[2] Burtscher H. Physical characterization of particulate emissions from diesel engines: a review. J Aerosol Sci 2005 Jul 1;36(7):896e932.[3] Chen H, Shi-Jin S, Jian-Xin W. Study on combustion characteristics and PM emission of diesel engines using estereethanolediesel blended fuels. Proc Combust Inst 2007 Jan 1;31(2):2981e9.[4] Sathiyagnanam AP, Saravanan CG, Gopalakrishnan M. Hexanol-ethanol diesel blends on DI-diesel engine to study the combustion and emission. Proc WRI World Congr Comput Sci Inf Eng 2010 Jun 30;2:1e5.[5] Azizb A. PM emission of diesel engines using ester-ethanoldiesel blended fuel. Procedia Eng 2013;53:530e5.[6] Heydari-Maleney K, Taghizadeh-Alisaraei A, Ghobadian B, Abbaszadeh-Mayvan A. Analyzing and evaluation of carbon nanotubes additives to diesohol-B2 fuels on performance and emission of diesel engines. Fuel 2017 May 15;196:110e23.[7] Ahmadipour S, Aghkhani MH, Zareei J. Investigation of injection timing and different fuels on the diesel engine performance and emissions. J Comput Appl Res Mech Eng 2020 Feb 1;9(2):385e96.[8] Jamrozik A, Grab-Rogalinski K, Tutak W. Hydrogen effects on combustion stability, performance and emission of diesel engine. Int J Hydrogen Energy 2020 Jul 31;45(38):19936e47.[9] Park H, Shim E, Lee J, Oh S, Kim C, Lee Y, Kang K. Largeesquish piston geometry and early pilot injection for high efficiency and low methane emission in natural gasediesel dual fuel engine at higheload operations. Fuel 2022 Jan 15;308:122015.[10] Zareei J, Kakaee AH. Study and the effects of ignition timing on gasoline engine performance and emissions. European Transport Res Review 2013 Jun 1;5(2):109e16.[11] Zareei J, Rohani A. Optimization and study of performance parameters in an engine fueled with hydrogen. Int J Hydrog Energy 2020 Jan 1;45(1):322e36.[12] Bayramoglu K, Yılmaz S. Emission and performance estimation in hydrogen injection strategies on diesel engines. Int J Hydrog Energy 2021 Aug 18;46(57):29732e44.[13] Raine RR, Stephenson J, Elder ST. Characteristics of diesel engines converted to spark ignition operation fuelled with natural gas. SAE Technical Paper; 1988 Feb 1.[14] Mittal M, Donahue R, Winnie P, Gillette A. Exhaust emissions characteristics of a multi-cylinder 18.1-L diesel engine converted to fueled with natural gas and diesel pilot. J Energy Inst 2015 Aug 1;88(3):275e83.[15] Luo H, Chang F, Jin Y, Ogata Y, Matsumura Y, Ichikawa T, Kim W, Nakashimada Y, Nishida K. Experimental investigation on performance of hydrogen additions in natural gas combustion combined with CO2. Int J Hydrog Energy 2021 Oct 11;46(70):34958e69.[16] Liu J, Dumitrescu CE. Single and double Wiebe function combustion model for a heavy-duty diesel engine retrofitted to natural-gas spark-ignition. Appl Energy 2019 Aug 15;248:95e103.[17] Likhanov VA, Rossokhin AV. The impact of the use of compressed natural gas in a car diesel engine on the formation and oxidation of soot particles. InIOP Conference Series: Mater Sci Eng 2020 Jan;734(1):12207. IOP Publishing.[18] Liu J, Dumitrescu CE. Improved thermodynamic model for lean natural gas spark ignition in a diesel engine using a triple Wiebe function. J Energy Resour Technol 2020 Jun 1;142(6).[19] Liu J, Dumitrescu CE. Investigation of multistage combustion inside a heavy-duty natural-gas spark-ignition engine using 3D CFD simulations and the wiebe-function combustion model. J Eng Gas Turbines Power 2020 Jan 1;142(10).[20] Duan X, Liu Y, Liu J, Lai MC, Jansons M, Guo G, Zhang S, Tang Q. Experimental and numerical investigation of the effects of low-pressure, high-pressure and internal EGR configurations on the performance, combustion and emission characteristics in a hydrogen-enriched heavy-duty lean-burn natural gas SI engine. Energy Convers Manag 2019 Sep 1;195:1319e33.[21] Chen H, He J, Zhong X. Engine combustion and emission fuelled with natural gas: a review. J Energy Inst 2019 Aug 1;92(4):1123e36.[22] Ouchikh S, Lounici MS, Tarabet L, Loubar K, Tazerout M. Effect of natural gas enrichment with hydrogen on combustion characteristics of a dual fuel diesel engine. Int J Hydrog Energy 2019 May 21;44(26):13974e87.[23] Lee CF, Pang Y, Wu H, Hernandez JJ, Zhang S, Liu F. The optical investigation of hydrogen enrichment effects on combustion and soot emission characteristics of CNG/diesel dual-fuel engine. Fuel 2020 Nov 15;280:118639.[24] Hairuddin AA, Yusaf T, Wandel AP. A review of hydrogen and natural gas addition in diesel HCCI engines. Renew Sustain Energy Rev 2014 Apr 1;32:739e61.[25] Das S, Kanth S, Das B, Debbarma S. Experimental evaluation of hydrogen enrichment in a dual-fueled CRDI diesel engine. Int J Hydrogen Energy 2022 Feb 9;47(20):11039e51.[26] Ismael MA, Aziz AR, Mohammed SE, Baharom MB, Raheem AT, Ayandotun WB, et al. Experimental study on combustion stability and performance of hydrogen-enriched compressed natural gas of a free-piston linear generator. Int J Hydrogen Energy 2021 Nov 16;46(79):39536e47.[27] Park C, Lee S, Kim C, Choi Y. A comparative study of lean burn and exhaust gas recirculation in an HCNG-fueled heavy-duty engine. Int J Hydrogen Energy 2017 Oct 12;42(41):26094e101.[28] Liu YF, Liu B, Zeng K, Huang Z, Zhou L, Sun L. Performance and emission characteristics of a hydrogen-enriched compressed-natural-gas direct-injection spark ignition engine diluted with exhaust gas recirculation. Proc Inst Mech Eng - Part D J Automob Eng 2012 Jan;226(1):123e32.[29] Zhao L, Wang D. Combined effects of cooled EGR and air dilution on butanolegasoline TGDI engine operation, efficiency, gaseous, and PM emissions. ACS Omega 2020 Mar 23;5(12):6556e65.[30] Imran S, Korakianitis T, Shaukat R, Farooq M, Condoor S, Jayaram S. Experimentally tested performance and emissions advantages of using natural-gas and hydrogen fuel mixture with diesel and rapeseed methyl ester as pilot fuels. Appl Energy 2018 Nov 1;229:1260e8.[31] Mehra RK, Duan H, Luo S, Rao A, Ma F. Experimental and artificial neural network (ANN) study of hydrogen enriched compressed natural gas (HCNG) engine under various ignition timings and excess air ratios. Appl Energy 2018 Oct 15;228:736e54.[32] Aydın M, Uslu S, C¸ elik MB. Performance and emission prediction of a compression ignition engine fueled with biodiesel-diesel blends: a combined application of ANN and RSM based optimization. Fuel 2020 Jun 1;269:117472.[33] Yaliwal VS, Banapurmath NR, Soudagar ME, Afzal A, Ahmadi P. Effect of manifold and port injection of hydrogen and exhaust gas recirculation (EGR) in dairy scum biodiesellow energy content gas-fueled CI engine operated on dual fuel mode. Int J Hydrog Energy 2022 Feb 1;47(10):6873e97.[34] Uslu S. Optimization of diesel engine operating parameters fueled with palm oil-diesel blend: comparative evaluation between response surface methodology (RSM) and artificial neural network (ANN). Fuel 2020 Sep 15;276:117990.[35] Hora TS, Agarwal AK. Effect of varying compression ratio on combustion, performance, and emissions of a hydrogen enriched compressed natural gas fuelled engine. J Nat Gas Sci Eng 2016 Apr 1;31:819e28.[36] Verhelst S, Wallner T. Hydrogen-fueled internal combustion engines. Prog Energy Combust Sci 2009 Dec 1;35(6):490e527.[37] Mabadi Rahimi H, Jazayeri SA, Ebrahimi M. Multi-objective optimization of a RCCI engine fueled with diesel fuel and natural gas enriched with hydrogen. Gas Processing Journal 2021 Jul 1;9(2):33e42.[38] Balamurugan G, Gowthaman S. A review on split injection performances in DI diesel engine with different injection strategies and varying EGR using biodiesel as fuel. Mater Today Proc 2021 Feb 20.[39] Balijepalli R, Kumar A, Rajak U, Elkotb MA, Alwetaishi M, Dasore A, Verma TN, Saleel CA, Afzal A. Numerical investigation of the effect of spray angle on emission characteristics of a diesel engine fueled with natural gas and diesel. Energy Rep 2021 Nov 1;7:7273e87.[40] Bose PK, Maji D. An experimental investigation on engine performance and emissions of a single cylinder diesel engine using hydrogen as inducted fuel and diesel as injected fuel with exhaust gas recirculation. Int J Hydrog Energy 2009 Jun 1;34(11):4847e54.[41] CFD A. Solver users guide [z]. AVL FIRE; 2013.[42] Kostic O, Stefanovi c Z, Kosti c I. CFD modeling of supersonic airflow generated by 2D nozzle with and without an obstacle at the exit section. FME Transactions 2015;43(2):107e13.[43] de Morais AM, Justino MA, Valente OS, de Morais Hanriot S, Sodre JR. Hydrogen impacts on performance and CO2 emissions from a diesel power generator. Int J Hydrog Energy 2013 May 30;38(16):6857e64.[44] Agarwal D, Singh SK, Agarwal AK. Effect of Exhaust Gas Recirculation (EGR) on performance, emissions, deposits and durability of a constant speed compression ignition engine. Appl Energy 2011 Aug 1;88(8):2900e7.[45] Williams CK, Rasmussen CE. Gaussian processes for machine learning. Cambridge, MA: MIT press; 2006.[46] Arthur CK, Temeng VA, Ziggah YY. A Self-adaptive differential evolutionary extreme learning machine (SaDEELM): a novel approach to blast-induced ground vibration prediction. SN Appl Sci 2020 Nov;2(11):1e23.[47] Snelson E, Ghahramani Z. Local and global sparse Gaussian process approximations. InArtificial Intelligence and Statistics 2007 Mar 11:524e31. PMLR.[48] Arthur CK, Temeng VA, Ziggah YY. Soft computing-based technique as a predictive tool to estimate blast-induced ground vibration. J Sustain Mining 2019 Nov 1;18(4):287e96.[49] Nocedal J, Wright SJ. Large-scale unconstrained optimization. Numerical Opt 2006:164e92.[50] Anil R, Pereyra G, Passos A, Ormandi R, Dahl GE, Hinton GE. Large scale distributed neural network training through online distillation. arXiv preprint arXiv:1804.03235 2018 Apr 9.[51] Li W, Liu Z, Wang Z, Dou H. Experimental and theoretical analysis of effects of atomic, diatomic and polyatomic inert gases in air and EGR on mixture properties, combustion, thermal efficiency and NOx emissions of a pilot-ignited NG engine. Energy Convers Manag 2015 Nov 15;105:1082e95.[52] Hu E, Huang Z. Optimization on ignition timing and EGR ratio of a spark-ignition engine fuelled with natural gas-hydrogen blends. SAE Technical Paper; 2011 Apr 12.[53] Zhou J, Guo Y, Huang Z, Wang C. A review and prospects of gas mixture containing hydrogen as vehicle fuel in China. Int J Hydrog Energy 2019 Nov 12;44(56):29776e84.[54] Khodamrezaee F, Keshavarz A. Thermodynamic and experimental analysis of hydrogen addition to CNG in a spark ignition engine for emission reduction. Energy Sources, Part A Recovery, Util Environ Eff 2020 Apr 4:1e2.[55] Park BY, Lee KH, Park J. Conceptual approach on feasible hydrogen contents for retrofit of CNG to HCNG under heavyduty spark ignition engine at low-to-middle speed ranges. Energies 2020 Jan;13(15):3861.[56] Hao D, Mehra RK, Luo S, Nie Z, Ren X, Fanhua M. Experimental study of hydrogen enriched compressed natural gas (HCNG) engine and application of support vector machine (SVM) on prediction of engine performance at specific condition. Int J Hydrog Energy 2020 Feb 14;45(8):5309e25.[57] Huang Z, Huang J, Luo J, Hu D, Yin Z. Performance enhancement and emission reduction of a diesel engine fueled with different biodiesel-diesel blending fuel based on the multi-parameter optimization theory. Fuel 2022 Apr 15;314:122753.[58] Kumar BR, Saravanan S, Rana D, Anish V, Nagendran A. Effect of a sustainable biofuelen-octanoleon the combustion, performance and emissions of a DI diesel engine under naturally aspirated and exhaust gas recirculation (EGR) modes. Energy Convers Manag 2016 Jun 15;118:275e86.[59] Kanth S, Ananad T, Debbarma S, Das B. Effect of fuel opening injection pressure and injection timing of hydrogen enriched rice bran biodiesel fuelled in CI engine. Int J Hydrog Energy 2021 Aug 13;46(56):28789e800.[60] Zareei J, Rohani A, Mazari F, Mikkhailova MV. Numerical investigation of the effect of two-step injection (direct and port injection) of hydrogen blending and natural gas on engine performance and exhaust gas emissions. Energy 2021 Sep 15;231:120957.[61] Lee S, Kim G, Bae C. Lean combustion of stratified hydrogen in a constant volume chamber. Fuel 2021 Oct 1;301:121045.[62] Long Y, Li G, Zhang Z, Liang J. Application of reformed exhaust gas recirculation on marine LNG engines for NOx emission control. Fuel 2021 May 1;291:120114.21581215655047Exhaust gas recirculationDiesel enginePerformanceExhaust emissionsMulti-objective genetic algorithm (MOGA)Cumulative heat releasePublicationORIGINALThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine.pdfThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine.pdfapplication/pdf5528295https://repositorio.cuc.edu.co/bitstreams/9ef85389-bfd5-4f28-97c7-2fd2c03b9ddd/downloadd4618ecba066f55baa161ef0c9ef514aMD51LICENSElicense.txtlicense.txttext/plain; charset=utf-83196https://repositorio.cuc.edu.co/bitstreams/2426e5ba-d6fd-4639-bd2d-f30b10fd02e7/downloade30e9215131d99561d40d6b0abbe9badMD52TEXTThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine.pdf.txtThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine.pdf.txttext/plain62320https://repositorio.cuc.edu.co/bitstreams/1136fc1c-2333-4fe0-98d7-1ded9a415fc7/downloadabcf3f4293439d2368d34b5114aa6093MD53THUMBNAILThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine.pdf.jpgThe effect of EGR and hydrogen addition to natural gas on performance and exhaust emissions in a diesel engine.pdf.jpgimage/jpeg15657https://repositorio.cuc.edu.co/bitstreams/ebb8a0b2-0956-4366-afd5-6b8ffd957611/download43bb08f12b84c3dede622a218e8515d4MD5411323/9329oai:repositorio.cuc.edu.co:11323/93292024-09-17 11:00:53.07https://creativecommons.org/licenses/by-nc-nd/4.0/Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)open.accesshttps://repositorio.cuc.edu.coRepositorio de la Universidad de la Costa CUCrepdigital@cuc.edu.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