Effect of different additives on performance of natural gas HCCI engine based on simulation

doi:10.3969/j.issn.1674-8484.2022.02.020

Abstract

Abstract:

Aiming at the misfire problem of natural gas mixed homogeneous compression ignition (HCCI) engine at low load, a three-dimensional model of the modified single cylinder engine was built to study the effect of hydrogen (H₂), ozone (O₃) and dimethyl ether (DME) as the additives on combustion characteristics and combustion-supporting mechanism. The results show that the three additive components can change the autoignition characteristics of natural gas-air mixture, enhance the ignition ability, and advance the combustion phase, all of which can realize the expansion of natural gas HCCI to the low load range. Radical OH is an important component to enhance the combustion of natural gas HCCI. The combustion-supporting mechanism of H₂ and O₃ is to increase the concentration of free-radical OH and accelerate the reaction rate of methane consumption, while combustion-supporting mechanism of DME is to ignite natural gas. H₂ is an excellent additive to extend the low load operation boundary of natural gas HCCI engine.

Key words: homogeneous charge compression ignition (HCCI) engine, additive, natural gas, hydrogen, ozone, dimethyl ether (DME)

CLC Number:

TK421

SUN Nannan, WANG Xiaoyan, WANG Dan, JIA Demin. Effect of different additives on performance of natural gas HCCI engine based on simulation[J]. Journal of Automotive Safety and Energy, 2022, 13(2): 386-396.

Figures/Tables 20

References 26

[1]	Onishi S, Hong J S, Shoda K, et al. Active thermo-atmosphere combustion (ATAC): A new combustion process for internal combustion engines[J]. SAE Paper, 1979, 790501.
[2]	Thring R H. Homogenous charge compression ignition (HCCI) engines[J]. SAE Paper, 1989, 892068.
[3]	郑清平, 张惠明, 张德福. 压燃式天然气发动机的技术现状及展望[J]. 农业机械学报, 2004, 35(5): 215-219.
	ZHENG Qingping, ZHANG Huiming, ZHANG Defu. Review and prospect on technologies of compression-ignited combustion engine by natural gas[J]. Trans Chin Soc Agri Mach, 2004, 35(5): 215-219. (in Chinese)
[4]	ZHAO Hua. HCCI and CAI Engines for the Automotive Industry[M]. Woodhead Publishing Limited, Cambridge CB21 6AH, England, 2007: 365-392.
[5]	WANG Zhongshu, DU Guizhi, LI Zhijie, et al. Study on the combustion characteristics of a high compression ratio HCCI engine fueled with natural gas[J]. Fuel, 2019, 255: 115701. doi: 10.1016/j.fuel.2019.115701 URL
[6]	DU Guizhi, WANG Zhongshu, WANG Dan, et al. Study on the effect of water addition on combustion characteristics of a HCCI engine fueled with natural gas[J]. Fuel, 2020, 270: 117547. doi: 10.1016/j.fuel.2020.117547 URL
[7]	Jamsran N, Lim O. Effects of EGR and boosting on the auto-ignition characteristics of HCCI combustion fueled with natural gas[J]. J Natu Gas Sci Engi, 2016, 35: 1015-1024.
[8]	ZHANG Zunhua, QIAN Xie, LIANG Junjie, et al. Numerical study of combustion characteristics of a natural gas HCCI engine with closed loop exhaust-gas fuel reforming[J]. Appl Therm Engi, 2017, 119: 430-437.
[9]	Hyunwoo S, Sonnho S. Predicting performance of a methane-fueled HCCI engine with hydrogen addition considering knock resistance[J]. Int’l J Hydro Energ, 2015, 40: 15749-11759.
[10]	Pourfallah M, Armin M. An experimental and numerical study of the effects of reformer gas (H2 and CO) enrichment on the natural gas homogeneous charge compression ignition (HCCI) engine[J]. Heat Mass Transf, 2019, 55: 1947-1957. doi: 10.1007/s00231-018-2479-z URL
[11]	Ahari M F, Neshat E. Advanced analysis of various effects of water on natural gas HCCI combustion, emissions and chemical procedure using artificial inert species[J]. Energy, 2019, 171: 842-852. doi: 10.1016/j.energy.2019.01.059 URL
[12]	Salahi M M, Gharehghani A. Control of combustion phasing and operating range extension of natural gas PCCI engines using ozone species[J]. Energ Conv Manag, 2019, 199: 112000. doi: 10.1016/j.enconman.2019.112000 URL
[13]	Gas Research Institute. GRI-Mech [/OL]. (2019-05-16), http://combustion.berkeley.edu/gri-mech.
[14]	Halter F, Higelin P, Dagaut P. Experimental and detailed kinetic modeling study of the effect of ozone on the com-bustion of methane[J]. Energ Fuel, 2011, 25: 2909-2016. doi: 10.1021/ef200550m URL
[15]	Lawrence Livermore National Laboratory. Mechanisms, dimethy ether[/OL]. (2019-05-16), https://combustion.llnl.gov/mechanisms/dimethyl-ether.
[16]	Moradi J, Gharehgani A, Mirsalim M. Numerical comparison of combustion characteristics and cost between hydrogen, oxygen and their combinations addition on natural gas fueled HCCI engine[J]. Energ Conv Manag, 2020, 222: 113254. doi: 10.1016/j.enconman.2020.113254 URL
[17]	Gharehghani A. Load limits of an HCCI engine fueled with natural gas, ethanol, and methanol[J]. Fuel, 2019, 239: 1001-1014. doi: 10.1016/j.fuel.2018.11.066
[18]	WANG Qian, ZHAO Yan, WU Fan. Study on the combustion characteristics and ignition limits of the methane homogeneous charge compression ignition with hydrogen addition in micro-power devices[J]. Fuel, 2019, 236: 354-364. doi: 10.1016/j.fuel.2018.09.010
[19]	Yousefzadeh A, Jahanian O. Using detailed chemical kinetics 3D-CFD model to investigate combustion phase of a CNG-HCCI engine according to control strategy requirements[J]. Energ Conv Manag, 2017, 133: 524-534. doi: 10.1016/j.enconman.2016.10.072 URL
[20]	Jahanian O, Jazayeri S A. A comprehensive numerical study on effects of natural gas composition on the operation of an HCCI engine[J]. Oil Gas Sci Tech, 2012, 67: 503-515. doi: 10.2516/ogst/2011133 URL
[21]	白敏丽, 朱国朝, 李河, 等. 臭氧强化内燃机燃烧研究[J]. 内燃机工程, 1999, 4: 28-31.
	BAI Minli, ZHU Guochao, LI He, et al. Stuay on combustion enhancement of internal combustion engine by ozone[J]. Inte Combust Engine Engineering, 1999, 4: 28-31. (in Chinese)
[22]	Ombrello T, Won S H, Ju Y, Williams S. Flame propaga-tion enhancement by plasma excitation of oxygen. Part I: Effects of O₃[J]. Combust Flame, 2010, 157: 1906-1915. doi: 10.1016/j.combustflame.2010.02.005 URL
[23]	GAO Xiang, ZHANG Yao, Adusumilli S, et al. The effect of ozone addition on laminar flame speed[J]. Combust Flame, 2015, 162: 3914-3924. doi: 10.1016/j.combustflame.2015.07.028 URL
[24]	周龙保, 刘忠长, 高宗英. 内燃机学[M]. 北京: 机械工业出版社, 2010:142-143.
	ZHOU Longbao, LIU Zhongchang, GAO Zongying. Internal Combustion Engine[M]. Beijing: China Machine Press, 2010, 6: 142-143. (in Chinese)
[25]	Kong S C. A study of natural gas/DME combustion in HCCI engines using CFD with detailed chemical kinetics[J]. Fuel, 2007, 86: 1483-1439. doi: 10.1016/j.fuel.2006.11.015 URL
[26]	CHEN Zhili, Konno M, Oguma M, et al. Experimental study of CI natural-gas/DME homogeneous charge engine[J]. SAE Paper, 2000-01-0329.

发动机类型	卧式单缸四冲程水冷
缸径×行程	80 mm × 80 mm
排量	402 mL
压缩比	19.5
天然气喷射方式	进气道喷射
气门数	2

发动机类型	卧式单缸四冲程水冷
缸径×行程	80 mm × 80 mm
排量	402 mL
压缩比	19.5
天然气喷射方式	进气道喷射
气门数	2

组分	体积分数 / %
甲烷	88.70
乙烷	5.45
丙烷	2.32
丁烷等高碳烷烃	1.82
氮气	1.08
二氧化碳	0.63

组分	体积分数 / %
甲烷	88.70
乙烷	5.45
丙烷	2.32
丁烷等高碳烷烃	1.82
氮气	1.08
二氧化碳	0.63

理化特性	天然气	H₂	O₃	DME
沸点 / ℃	- 162	- 253	- 111.9	- 24.9
自燃温度 / ℃	650	585	-	235
辛烷值	130	-	-	-
十六烷值	-	低	-	> 55
化学计量空燃比	16.4	34.3	-	8.9
低热值 / (MJ·kg^-1)	50	120	-	27.6
蒸发热 / (kJ·kg^-1)	-	-	316.5	410
空气中体积比浓着火极限 / %	13.9	74.2	-	18.0
空气中体积比稀着火极限 / %	5.0	4.2~	-	3.4