The Journal of Engine Research

The Journal of Engine Research

The effect of nozzle holes number with a focus on spray dynamics characteristics and its role in the performance and emissions of an RCCI engine

Document Type : Original Article

Authors
Mehran Nazemian 1
Mehrdad Nazemian 2
1 Mechanical Department, Vahdat institute of Higher Education, Torbat-e Jam, Iran
2 Mechanical Engineering Department, Sahand University of Technology, Tabriz, Iran
10.22034/er.2025.2048475.1072
Abstract
In this study, the effect of nozzle hole number on fuel injection, atomization, mixing quality, combustion characteristics, and exhaust emissions in an RCCI engine was investigated using three-dimensional simulations in CONVERGE software. The results revealed that increasing the number of nozzle holes leads to a reduction in fuel injection pressure and velocity, consequently cumulative the Sauter mean diameter. This reduction in kinetic energy and turbulence weakens both primary and secondary droplet breakup processes, significantly lowering fuel evaporation rates and mixing quality. With a 3-hole nozzle, the high kinetic energy of the spray resulted in finer droplets, faster evaporation, and improved fuel- air mixing, leading to a shorter ignition delay and enhanced combustion and gross indicated efficiency, which were 17.03 degrees, 92.1%, and 39.4%, respectively. Conversely, increasing the hole number to 6 (baseline) and 9 reduced spray kinetic energy and enlarged droplet sizes, which increased the mixing duration and combustion period, thereby deteriorating the atomization process. From an emissions perspective, a higher number of nozzle holes caused an increase in HC and CO emissions due to incomplete combustion, while NOx emissions decreased as a result of lower peak combustion temperatures. The findings demonstrate that nozzles with fewer holes significantly enhance combustion performance and thermal efficiency in RCCI engines by improving atomization, promoting efficient fuel- air mixing, and reducing ignition delay.
Keywords
RCCI Engine
Nozzle Hole Number
Fuel Atomization
Combustion Efficiency
Exhaust Emissions
[1] William J. The Federal Government's Role in Reducing Heavy Duty Diesel Emissions. SAE Technical Paper. 2004 Oct 26. doi: 10.4271/2004-01-2708
[2] Kamimoto T, Yokota H, Kobayashi H. Effect of high pressure injection on دوده formation processes in a rapid compression machine to simulate diesel flames. SAE transactions. 1987 Jan 1:783-91. doi: 10.4271/871610
[3] Li J, Yang W, Zhou D. Review on the management of RCCI engines. Renewable and Sustainable Energy Reviews. 2017 Mar 1;69:65-79. doi: 10.1016/j.rser.2016.11.159
[4] Splitter D, Wissink M, Kokjohn S, Reitz RD. Effect of compression ratio and piston geometry on RCCI load limits and efficiency. SAE Technical Paper. 2012 Apr 16. doi: 10.4271/2012-01-0383
[5] Dempsey AB, Walker NR, Reitz R. Effect of piston bowl geometry on dual fuel reactivity controlled compression ignition (RCCI) in a light-duty engine operated with gasoline/diesel and methanol/diesel. SAE International Journal of Engines. 2013 May 1;6(1):78-100. doi: 10.4271/2013-01-0264
[6] Kakaee AH, Nasiri-Toosi A, Partovi B, Paykani A. Effects of piston bowl geometry on combustion and emissions characteristics of a natural gas/diesel RCCI engine. Applied Thermal Engineering. 2016 Jun 5;102:1462-72. doi: 10.1016/j.applthermaleng.2016.03.162
[7] Nazemian M, Neshat E, Saray RK, Poorghasemi K. Investigation of the effect of piston geometrical parameters on RCCI engine performance based on second law of thermodynamic. The Journal of Engine Research. 2022 Nov 27;51(51):21-34. [In Persian]
[8] Nazemian M, Neshat E, Saray RK. Effects of piston geometry and injection strategy on the capacity improvement of waste heat recovery from RCCI engines utilizing DOE method. applied thermal engineering. 2019 Apr 1;152:52-66. doi: 10.1016/j.applthermaleng.2019.02.055
 [9] Poorghasemi K, Saray RK, Ansari E, Irdmousa BK, Shahbakhti M, Naber JD. Effect of diesel injection strategies on natural gas/diesel RCCI combustion characteristics in a light duty diesel engine. Applied energy. 2017 Aug 1;199:430-46. doi: 10.1016/j.apenergy.2017.05.011
[10] Nazemi M, Shahbakhti MJ. Modeling and analysis of fuel injection parameters for combustion and performance of an RCCI engine. Applied Energy. 2016 Mar 1;165:135-50. doi: 10.1016/j.apenergy.2015.11.093
[11] Benajes J, Molina S, García A, Belarte E, Vanvolsem M. An investigation on RCCI combustion in a heavy duty diesel engine using in-cylinder blending of diesel and gasoline fuels. Applied Thermal Engineering. 2014 Feb 5;63(1):66-76. doi: 10.1016/j.applthermaleng.2013.10.052
[12] Li Y, Jia M, Liu Y, Xie M. Numerical study on the combustion and emission characteristics of a methanol/diesel reactivity controlled compression ignition (RCCI) engine. Applied energy. 2013 Jun 1;106:184-97. doi: 10.1016/j.apenergy.2013.01.058
[13] Nieman DE, Dempsey AB, Reitz RD. Heavy-duty RCCI operation using natural gas and diesel. SAE International Journal of Engines. 2012 May 1;5(2):270-85. doi: 10.4271/2012-01-0379
[14] Li Y, Jia M, Chang Y, Liu Y, Xie M, Wang T, Zhou L. Parametric study and optimization of a RCCI (reactivity controlled compression ignition) engine fueled with methanol and diesel. Energy. 2014 Feb 1;65:319-32. doi: 10.1016/j.energy.2013.11.059
[15] Li J, Yang W, Zhou D. Review on the management of RCCI engines. Renewable and Sustainable Energy Reviews. 2017 Mar 1;69:65-79. doi: 10.1016/j.rser.2016.11.159
[16] Liu H, Wang X, Zheng Z, Gu J, Wang H, Yao M. Experimental and simulation investigation of the combustion characteristics and emissions using n-butanol/biodiesel dual-fuel injection on a diesel engine. Energy. 2014 Sep 1;74:741-52. doi: 10.1016/j.energy.2014.07.041
[17] Yu C, Wang J, Yu W, Liu J, Gao D. Research on low temperature combustion of homogeneous charge induced ignition (HCII) in a light-duty diesel engine. InProceedings of the FISITA 2012 World Automotive Congress: Volume 1: Advanced Internal Combustion Engines (I) 2012 Nov 2 (pp. 195-204). Berlin, Heidelberg: Springer Berlin Heidelberg. doi: 10.1007/978-3-642-33841-0_15
[18] Ma S, Zheng Z, Liu H, Zhang Q, Yao M. Experimental investigation of the effects of diesel injection strategy on gasoline/diesel dual-fuel combustion. Applied energy. 2013 Sep 1;109:202-12. doi: 10.1016/j.apenergy.2013.04.012
[19] Wu Y, Reitz RD. Effects of exhaust gas recirculation and boost pressure on reactivity controlled compression ignition engine at high load operating conditions. Journal of Energy Resources Technology. 2015 May 1;137(3):032210. doi: 10.1115/1.4029866
[20] Liu H, Wang X, Zheng Z, Gu J, Wang H, Yao M. Experimental and simulation investigation of the combustion characteristics and emissions using n-butanol/biodiesel dual-fuel injection on a diesel engine. Energy. 2014 Sep 1;74:741-52. doi: 10.1016/j.energy.2014.07.041
[21] Asad U, Divekar P, Zheng M, Tjong J. Low temperature combustion strategies for compression ignition engines: operability limits and challenges. SAE Technical Paper. 2013 Apr 8. doi: 10.4271/2013-01-0283
[22] Paykani A, Kakaee AH, Rahnama P, Reitz RD. Effects of diesel injection strategy on natural gas/diesel reactivity controlled compression ignition combustion. Energy. 2015 Oct 1;90:814-26. doi: 10.1016/j.energy.2015.07.112
[23] Benajes J, Garcia A, Monsalve-Serrano J, Boronat V. Particulates size distribution of reactivity controlled compression ignition (RCCI) on a medium-duty engine fueled with diesel and gasoline at different engine speeds. SAE International Journal of Engines. 2017 Dec 1;10(5):2382-91. doi: 10.4271/2017-24-0085
[24] Dahodwala M, Joshi S, Koehler E, Franke M, Tomazic D. Experimental and computational analysis of diesel-natural gas RCCI combustion in heavy-duty engines. SAE Technical Paper. 2015 Apr 14. doi: 10.4271/2015-01-0849
[25] Hanson R, Ickes A, Wallner T. Comparison of RCCI operation with and without EGR over the full operating map of a heavy-duty diesel engine. SAE Technical Paper. 2016 Apr 5. doi: 10.4271/2016-01-0794
[26] Wang Y, Zhu Z, Yao M, Li T, Zhang W, Zheng Z. An investigation into the RCCI engine operation under low load and its achievable operational range at different engine speeds. Energy conversion and management. 2016 Sep 15;124:399-413. doi: 10.1016/j.enconman.2016.07.026
[27] Splitter D, Wissink M, Kokjohn S, Reitz RD. Effect of compression ratio and piston geometry on RCCI load limits and efficiency. SAE Technical Paper. 2012 Apr 16. doi: 10.4271/2012-01-0383
[28] Moon S, Gao Y, Park S, Wang J, Kurimoto N, Nishijima Y. Effect of the number and position of nozzle holes on in-and near-nozzle dynamic characteristics of diesel injection. Fuel. 2015 Jun 15;150:112-22. doi: 10.1016/j.fuel.2015.01.097
[29] Zhao Y, Liu X, Kook S. Effect of three-hole nozzle orientations on sprays and combustion in methanol-diesel dual direct injection engines. Applied Thermal Engineering. 2024 Oct 1;254:123953. doi: 10.1016/j.applthermaleng.2024.123953
[30] Rojas-Reinoso EV, Morales-Chauca K, Lara-Lara J, Soriano JA, García-Contreras R. Adaptation and Validation of Injection Rate Predictive Model for Solenoid Type Injectors with Different Nozzle Geometry. Applied Sciences. 2024 Apr 17;14(8):3394. doi: 10.3390/app14083394
[31] Firuzi R, Bagherpoor F, Farajollahi A. Engine Injector Multiphase Flow with Indicated Quantities Simulation for Different Orifice Geometries and Needle Movements. The Journal of Engine Research. 2022 Feb 20;65(65):21-41. doi: 10.22034/er.2022.697904
[32] Yaliwal VS, Banapurmath NR, Gireesh NM, Hosmath RS, Donateo T, Tewari PG. Effect of nozzle and combustion chamber geometry on the performance of a diesel engine operated on dual fuel mode using renewable fuels. Renewable Energy. 2016 Aug 1;93:483-501. doi: 10.1016/j.renene.2016.03.020
[33] Yousef O, Mashkour M. Effects of Nozzle Diameter and Holes Number on the Performance and Emissions of a Gasoline Direct Injection Engine. International Journal of Thermodynamics. 2024 Jan 3;27(1):1-2. doi: 10.5541/ijot.1272871
[34] Nadimi E, Przybyła G, Løvås T, Adamczyk W. Effects of biodiesel injector configuration and its injection timing on performance, combustion and emissions characteristics of liquid ammonia dual direct injection engine. Journal of the Energy Institute. 2024 Jun 1;114:101605. doi: 10.1016/j.joei.2024.101605
[35] Kumaran SS, Raghu P. Effect of Nozzle Hole Number on Diesel Engine Using Diesel and Biodiesel Blends. InIOP Conference Series: Materials Science and Engineering 2020 Aug 1 (Vol. 912, No. 4, p. 042007). IOP Publishing. doi: 10.1088/1757-899X/912/4/042007
[36] Li Z, Zhang Q, Zhang F, Liang H, Zhang Y. Investigation of Effect of Nozzle Numbers on Diesel Engine Performance Operated at Plateau Environment. Sustainability. 2023 May 25;15(11):8561. doi: 10.3390/su15118561
[37] Dong S, Yang C, Ou B, Lu H, Cheng X. Experimental investigation on the effects of nozzle-hole number on combustion and emission characteristics of ethanol/diesel dual-fuel engine. Fuel. 2018 Apr 1;217:1-0. doi: 10.1016/j.fuel.2017.12.024
[38] Park SW, Reitz RD. Modeling the effect of injector nozzle-hole layout on diesel engine fuel consumption and emissions. InASME/IEEE Joint Rail Conference 2007 Jan 1 (Vol. 4787, pp. 375-389). doi: 10.1115/JRC/ICE2007-40022
[39] Moon S, Komada K, Sato K, Yokohata H, Wada Y, Yasuda N. Ultrafast X-ray study of multi-hole GDI injector sprays: Effects of nozzle hole length and number on initial spray formation. Experimental Thermal and Fluid Science. 2015 Nov 1;68:68-81. doi: 10.1016/j.expthermflusci.2015.03.027
[40] Zareei J, Alvarez JR. Analysis of the effect of the number of injector nozzles on the pressure and heat transfer coefficient in a hydrogen-diesel mixture diesel engine. International Journal of Hydrogen Energy. 2024 May 20;67:1148-56. doi: 10.1016/j.ijhydene.2023.11.175
[41] Jafari B, DOMIRI GD. Numerical investigation in the effect of number of nozzle hole on performance and emission in dual fuel engine. International Journal of Automotive Engineering. 2013 Jun; 412-423.
[42] Kothiwale GR, Akkoli KM, Doddamani BM, Kattimani SS, Ağbulut Ü, Afzal A, Kaladgi AR, Said Z. Impact of injector nozzle diameter and hole number on performance and emission characteristics of CI engine powered by nanoparticles. International journal of Environmental Science and Technology. 2023 May;20(5):5013-34. doi: 10.1007/s13762-022-04397-0
[43] Parravicini M, Barro C, Boulouchos K. Compensation for the differences in LHV of diesel-OME blends by using injector nozzles with different number of holes: Emissions and combustion. Fuel. 2020 Jan 1;259:116166. doi: 10.1016/j.fuel.2019.116166
[44] Som S, Ramirez AI, Longman DE, Aggarwal SK. Effect of nozzle orifice geometry on spray, combustion, and emission characteristics under diesel engine conditions. Fuel. 2011 Mar 1;90(3):1267-76. doi: 10.1016/j.fuel.2010.10.048
[45] Asef A, Mohammadi A, Khorramirad V, Ajami N, Parivar AH, Maghsoudi Mehraban K. Study of GDI injector in constant volume chamber by optical measurements and CFD-Simulation. The Journal of Engine Research. 2022 Dec 22;69(69):39-48. doi: 10.22034/er.2022.697928
[46] Rahimi A, Fatehifar E, Saray RK. Development of an optimized chemical kinetic mechanism for homogeneous charge compression ignition combustion of a fuel blend of n-heptane and natural gas using a genetic algorithm. Proceedings of the institution of mechanical engineers, Part D: Journal of Automobile Engineering. 2010 Sep 1;224(9):1141-59. doi: 10.1243/09544070JAUTO1343
[47] Wang H, Yao M, Reitz RD. Development of a reduced primary reference fuel mechanism for internal combustion engine combustion simulations. Energy & Fuels. 2013 Dec 19;27(12):7843-53. doi: 10.1021/ef401992e

  • Receive Date 21 December 2024
  • Revise Date 22 February 2025
  • Accept Date 23 March 2025