An experimental study on cycle-to-cycle combustion variations at different speeds in a common-rail diesel engine

Year 2024, Volume: 30 Issue: 4, 429 - 435, 30.08.2024

Ali Şanlı , İlker Turgut Yılmaz

Abstract

The objective of this study is to experimentally investigate cyclic combustion variabilities in a four-cylinder automotive common-rail diesel engine at different engine speeds, including 1600, 1800, and 2000 rpm. The investigation evaluates the relative effects of speeds on the cyclic discrepancies in a modern diesel engine. 1000 cyclic combustion data including peak combustion pressure (Pmax), peak pressure rise rate (PRRmax) and indicated mean effective pressure (IMEP) were analyzed in the experimental study. It was found that the cyclic fluctuations in combustion pressure in each engine speed were minor, but detailed comparison of Pmax, PRRmax, and IMEP revealed noteworthy differences in the studied cycles. Higher cylinder temperatures and air movement improved combustion. Therefore, not only coefficient of variations COVs of IMEP and Pmax decreased, but also mean Pmax and PRRmax increased with increasing engine speed. On the other hand, the friction effect of the intake air reduced the positive effects of improved combustion with increasing engine speed and as a result mean IMEP decreased. COVs of IMEP and Pmax remained below 1% at all speeds, thus stable and regular combustion was maintained even in a numerous range of the cycle numbers. Pre-injection phase of fuel injection system was recognized to be effective in formation of the first peak of the combustion pressure in individual cycles. It was concluded from this study that the common-rail diesel engine generated minor cyclic discrepancies under different engine speeds.

Keywords

Cyclic variations, Combustion parameters, Common-Rail diesel engine

Ortak hatlı bir dizel motorda farklı devirlerde çevrimden çevrime yanma değişimleri üzerine deneysel bir çalışma

Abstract

Bu çalışmanın amacı, dört silindirli ortak hatlı bir otomotiv dizel motorunda 1600, 1800, 2000 d/dk ’lık devirlerde çevrimsel yanma değişimlerini deneysel olarak incelemektedir. Çalışma, bir modern dizel motorda devir sayısının çevrimsel farklılıklara bağlı etkisini ele almaktadır. Maksimum yanma basıncı (SBmaks), maksimum basınç artış oranı (BAOmaks), ve ortalama indike basınç (OİB) parametrelerini kapsayan 1000 çevrimsel yanma verisi deneysel çalışmada analiz edilmiştir. Her bir motor hızında, silindir basıncındaki çevrimsel değişimlerin minimum olduğu, ancak SBmaks, BAOmaks ve OİB detaylı olarak karşılaştırıldıklarında incelenen çevrimlerde önemli farklılıklar ortaya çıkmıştır. Daha yüksek silindir sıcaklıkları ve hava hareketleri yanmayı iyileştirmiştir. Böylece, artan motor devriyle birlikte sadece OİB ve SBmaks’ın çevrimsel değişim katsayıları (ÇDK) azalırken, aynı zamanda ortalama SBmaks ve BAOmaks artmıştır. Diğer taraftan, artan devirle birlikte emme havasının sürtünme etkisi, iyileşen yanmanın pozitif etkilerini azaltmış ve sonuç olarak ortalama OİB azalmıştır. SBmaks ve OİB’nin ÇDK’ları tüm devirlerde %1’in altında kalmıştır, böylece oldukça geniş çevrim sayılarında bile stabil ve düzenli yanma sürdürülmüştür. Her bir çevrimde, yakıt sistemi ön enjeksiyon fazının, ilk yanma basınç pikinin oluşumunda etkili olduğu gözlenmiştir. Bu çalışmadan, ortak hatlı dizel motorun farklı devirlerde küçük çevrimsel farklılıklar meydana getirdiği sonucuna varılmıştır.

Keywords

Çevrimsel değişimler, Yanma parametreleri, Ortak hatlı dizel motor

References

• [1] Jagadish C, Gumtapure V. “Experimental studies on cyclic variations in a single cylinder diesel engine fuelled with raw biogas by dual mode of operation”. Fuel, 266, 1-11, 2020.
• [2] Kyrtatos P, Brückner C, Boulouchos K. “Cycle-to-cycle variations in diesel engines”. Applied Energy, 171, 120-132, 2016.
• [3] Selim MYE. “Effect of engine parameters and gaseous fuel type on the cyclic variability of dual fuel engines”. Fuel, 84(7-8), 961-971, 2005.
• [4] Galloni E. “Analyses about parameters that affect cyclic variation in a spark ignition engine”. Applied Thermal Engineering, 29, 1131-1137, 2009.
• [5] Saxena MR, Maurya RK. Characterization of Cycle-To-Cycle Variations in Conventional Diesel Engine Using Wavelets. Editors: Srivastava DK, Agarwal AK, Datta A, Maurya RK. Advances in Internal Combustion Engine Research, 135-155, Springer Singapore, 2018.
• [6] Heywood JB. Internal Combustion Engine Fundamentals. 1st ed. USA, McGraw-Hill Press, 1988.
• [7] Hamai K, Kawajiri H, Ishizuka T, Nakai M. “Combustion fluctuation mechanism involving cycle-to-cycle spark ignition variation due to flow motion in S.I. engines”. 21st Symposium (International) on Combustion, 21(1), 505-512, 1988.
• [8] Yu X, Wu H, Du Y, Tang Y, Liu L, Niu R. “Research on cycle-by-cycle variations of an SI engine with hydrogen direct injection under lean burn conditions”. Applied Thermal Engineering, 109, 569-581, 2016.
• [9] Shere A, Subramanian KA. “Experimental investigation on effects of fuel injection timings on dimethyl ether (DME) energy share improvement and emission reduction in a dual-fuel CRDI compression ignition engine”. International Journal of Automotive Science and Technology, 6(2), 98-112, 2022.
• [10] Gürbüz H, Buran D, Akçay İH. “An experimental study on performance and cyclic variations in a spark ignition engine fuelled with hydrogen and gasoline”. Journal of Thermal Science and Technology 33(1), 33-41, 2013.
• [11] Şanlı A, Yılmaz İT. “Cycle-to-cycle combustion analysis in hydrogen fumigated common-rail diesel engine”. Fuel, 320, 1-15, 2022.
• [12] Yasin MHM, Mamat R, Yusop AF, Abdullah AA, Othman MF, Yusrizal ST, Iqbal ST. “Cylinder pressure cyclic variations in a diesel engine operating with biodiesel-alcohol blends”. Energy Procedia, 142, 303-308, 2017.
• [13] Ceviz MA, Koncuk F, Küçük Ö, Gören AC, Yüksel F. “Analysis of combustion stability and its relation to performance characteristics in a compression ignition engine fueled with diesel-biodiesel blends”. Energy Souces Part A: Recovery, Utilization, and Environmental Effects, 33(10), 990-1003, 2011.
• [14] Lü X, Ji L, Ma J Huang Z. “Combustion stabilities and cycle-by-cycle variations of n-heptane homogeneous charge compression ignition combustion” Energy&Fuels, 21, 1468-1473, 2007.
• [15] Sjöberg M, Dec JE, Babajimopoulos A, Assanis D. “Comparing enhanced natural thermal stratification against retarded combustion phasing for smoothing of HCCI hheat-release rates”. Society of Automotive Engineering Technical Paper, 2004. https://doi.org/10.4271/2004-01-2994.
• [16] Yang Z, Steffen T, Stobart R. “Disturbance sources in the diesel engine combustion process”. Society of Automotive Engineering Technical Paper, 2013. doi:10.4271/2013-01-0318.
• [17] Sen AK, Longwic R, Litak G, Gorski K. “Analysis of cycle-to-cycle pressure oscillations in a diesel engine”. Mechanical Systems and Signal Processing, 22(2), 362-373,2008.
• [18] Şanlı A, Gümüş M. “Investigation of heat transfer in combustion chamber of a direct injection diesel engine under different compression ratios and engine torques”. Pamukkale University Journal of Engineering Sciences, 28(1), 91-103, 2022.
• [19] Şanlı H. “Investigation of waste animal fat based biodiesel fuels’ usage in a common rail direct injection diesel engine: performance and combustion characteristics”. Pamukkale University Journal of Engineering Sciences, 25(4), 396-402, 2019.
• [20] Yılmaz İT, Yavuz M, Gümüş M. “The effect of diesel fuel amount on emissions in a diesel-biogas dual-fuel engine”. Pamukkale University Journal of Engineering Sciences, 26(4), 683-688, 2020.
• [21] Chen Z, He J, Chen H, Geng L, Zhang P. “Experimental study on cycle-to-cycle variations in natural gas/methanol bi-fueled engine under excess air/fuel ratio at 1.6”. Energy, 224, 1-10, 2021.
• [22] Gupta SK, Mittal M. “Effects of compression ratio on the performance and emission characteristics, and cycle-to-cycle combustion variations of a spark-ignition engine fueled with bio-methane surrogate”. Applied Thermal Engineering, 148, 1440-1453, 2019.
• [23] Shi J, Wang T, Zhao Z, Wu Z, Zhang Z. “Cycle-to-cycle variation of a diesel engine fuelled with fischer-tropsch fuel synthesized from coal”. Applied Sciences, 9(10), 1-13, 2019.
• [24] Geng L, Li S, Xiao Y, Xie Y, Chen H, Chen X. “Effects of injection timing and rail pressure on combustion characteristics and cyclic variations of a common rail DI engine fuelled with F-T diesel synthesized from coal”. Journal of Energy Institute, 93(6), 2148-2162, 2020.
• [25] Henein NA, Lai M-C, Singh IP, Zhong L, Han J. “Characteristics of a common rail diesel injection system under pilot and post injection modes”. Society of Automotive Engineering Technical Paper, 2002. https://doi.org/10.4271/2002-01-0218.
• [26] Şanlı A. “Experimental study of combustion and cyclic variations in a CRDI engine fueled with heptanol/iso-propanol/butanol and diesel blends”. Energy, 269, 1-15, 2023.
• [27] Zhong L, Singh IP, Han J, Lai M-C, Henein NA, Bryzik W. “Effect of cycle-to-cycle variation in the injection pressure in a common rail diesel injection system on engine performance”. Society of Automotive Engineering Technical Paper, 2003. https://doi.org/10.4271/2003-01-0699.
• [28] Ali OM, Mamat R, Masjuki HH, Abdullah AA. “Analysis of blended fuel properties and cycle-to-cycle variation in a diesel engine with a diethyl ether additive”. Energy Conversion Management, 108, 511-519, 2016.
• [29] Ghadikolaei MA, Cheung C, Yung KF, Wong PA. “Impact of fueling methods on the combustion and cyclic variability in a compression ignition engine”. International Journal of Green Energy, 18(5), 474-489, 2021.
• [30] Ozkan M. “Comparative study of the effect of biodiesel and diesel fuel on a compression ignition engine’s performance, emissions, and its cycle by cycle variations”. Energy & Fuels, 21, 3627-3636, 2007.
• [31] Ozdor N, Dulger M, Sher E. “Cyclic variability in spark ignition engines a literature survey”. Society of Automotive Engineering Technical Paper, 1994. https://doi.org/10.4271/940987.
• [32] Wang S, Li Y, Fu J, Liu J, Dong H, Tong J. “Quantitative investigation of the effects of EGR strategies on performance, cycle-to-cycle variations and emissions characteristics of a higher compression ratio and heavy-duty NGSI engine fuelled with 99% methane content”. Fuel, 263, 1-14, 2020.
• [33] Karvountzis-Kontakiotis A, Ntziachristos L, Samaras Z, Dimaratos A. “Experimental investigation of cyclic variability on combustion and emissions of a high-speed SI engine”. Society of Automotive Engineering Technical Paper, 2015. https://doi.org/10.4271/2015-01-0742.
• [34] Ozdor N, Dulger M, Sher E. “An experimental study of the cyclic variability in spark ignition engines”. Society of Automotive Engineering Technical Paper, 1996. https://doi.org/10.4271/960611.
• [35] Öner İV, Ceviz MA, Güner E, Köksal H. “Cyclic variability in spark ignition engines”. Ordu University Journal of Science and Technology, 4(1), 27-35, 2014.