تحلیل انرژی و اگزرژی عملکرد یک موتور اشتعال جرقه‌ای با استفاده از مدل احتراق دوناحیه‌ای

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده فنی مهندسی، دانشگاه اصفهان، اصفهان، ایران

چکیده

امروزه با تکیه بر روش‌های عددی می‌توان عملکرد موتور را با دقت بسیار مناسبی شبیه‌سازی نمود و راهکارهای بهینه سازی عملکرد موتور را بررسی کرد. با توجه به این که در موتور حدود 30 درصد از انرژی سوخت از طریق انتقال حرارت  به دیواره‌های سیلندر هدر می‌رود، به دست آوردن نتایج مناسب از یک مدل شبیه سازی نیازمند محاسبه انتقال حرارت با دقت بالا است. مدل ترمودینامیکی ارائه شده در این مقاله، با هدف بهینه‌سازی یک موتور اشتعال جرقه‌ای، سیکل موتور را به صورت دو‌ناحیه‌ای، که برای موتور اشتعال جرقه‌ای مناسب است، شبیه سازی می‌نماید. جهت انتخاب بهترین مدل برای انتقال حرارت در موتور احتراق جرقه‌ای، مدل‌های مختلف در شبیه‌سازی استفاده شده و پس از مقایسه نتایج هر مدل با نتایج تجربی موتور مورد مطالعه، مدل هوهنبرگ به عنوان مدل مناسب برای انتقال حرارت موتورهای اشتعال جرقه‌ای معرفی گردیده است. نتایج نشان‌داد که با افزایش نسبت تراکم به میزان 18 درصد، تلفات اگزرژی از اگزوز موتور و انتقال حرارت از بدنه تقریباً 2 درصد کاهش می‌یابد در حالی که توان خروجی بیش از 4 درصد افزایش می یابد. همچنین، بیشینه راندمان انرژی و اگزرژی در هنگامی که احتراق 5 درجه قبل از نقطه مرگ بالا رخ دهد، حاصل می شود.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Energy and Exergy Analyses of the Performance of a Spark Ignition Engine Using Two-Zone Combustion Model

نویسندگان [English]

  • Ehasn Baniasadi
  • Hamidreza Abbasi Varzaneh
Assistant Professor / University of Isfahan
چکیده [English]

Relying on numerical methods, it is possible to estimate the performance of an engine precisely, and to evaluate the optimization methods of the engine. Almost 30% of the fuel energy is dissipated through the cylinder walls, therefore, accurate calculation of heat transfer rate is necessary to yield reliable results from the simulation model. The thermodynamic model in this paper, that is developed to optimize the performance of a spark ignition engine, utilizes the two-zone combustion model that is suitable for this type of engine. Different models for heat transfer in the engine are used in simulation and compared with available experimental data, and the Hohenberg model is identified as the most precise heat transfer model for spark ignition engine. The results indicate that increase of the compression ratio by 18% leads to almost 2% lower exergy destruction due to engine exhaust and heat transfer to the enegin body, however, the engine power output increases by about 4%. Also, it is concluded that the maximum energy and exergy efficiencies are obtained when combustion takes place 5 degree before top dead center.

کلیدواژه‌ها [English]

  • Thermodymaic model
  • Spark ignition engine
  • Energy and Exergy analysis
  • Heat ransfer and burning rate
  • Two-zone model

مراجع

[1] A. Nemati, H. Nami, M. Yari, S. F. Ranjbar, Energy and exergy analysis of a two-stage thermoelectric used for heating and cooling, Amirkabir Journal of Mechanical Engineering, (2017)- in Persian
[2] S. Soylu, J. Van Gerpen, Development of empirically based burning rate sub-models for a natural gas engine, Energy Conversion and Management, 45(4) (2004) 467-481.
[3] S. Farahat, M. M. Naserian, F. Sarhadi, Performance optimization of an irreversible Brayton cycle, and proposing new definitions for 2nd law efficiency and exergy, Amirkabir Journal of Mechanical Engineering, (2017)- in Persian
[4] P. Guibert, Engine cycle modeling–spark ignition engines, Technique de l’ingénieur BM, 2511 (2005) 1-28.
[5] A. Franco, L. Martorano, Evaluations on the heat transfer in the small two-stroke engines, 0148-7191, SAE Technical Paper, 1998.
[6] L. Eriksson, I. Andersson, An Analytic Model for Cylinder Pressure in a Four Stroke SI Engine, in, SAE International, 2002.
[7] A. Ibrahim, S. Bari, Optimization of a natural gas SI engine employing EGR strategy using a two-zone combustion model, Fuel, 87(10) (2008) 1824-1834.
[8] A. Ibrahim, S. Bari, A comparison between EGR and lean-burn strategies employed in a natural gas SI engine using a two-zone combustion model, Energy Conversion and Management, 50(12) (2009) 3129-3139.
[9] G. Woschni, A universally applicable equation for the instantaneous heat transfer coefficient in the internal combustion engine, 0148-7191, SAE Technical paper, 1967.
[10] C. Caillol, G. Berardi, G. Brecq, M. Ramspacher, P. Meunier, A simulation tool for evaluating gas composition effects on engine performance, in:  International gas research conference, Vacouver, 2004, pp. 1-19.
[11] O. jahanian, M. Namar, Defining Start and Duration of Combustion in HCCI Engines using Mean-Value Method for Control Applications, Amirkabir Journal of Mechanical Engineering, (2017)- in Persian
[12] M. Razmara, M. Bidarvatan, M. Shahbakhti, R. Robinett, Optimal exergy-based control of internal combustion engines, Applied Energy, 183 (2016) 1389-1403.
[13] P. Nemati, S. Jafarmadar, H. Taghavifar, Exergy analysis of biodiesel combustion in a direct injection compression ignition (CI) engine using quasi-dimensional multi-zone model, Energy, 115 (2016) 528-538.
[14] P. Bridjesh, G. Arunkumar, Energy and Exergy Analysis of Diesel Engine by Varying Compression Ratio, International Journal of Chemical Sciences, 13(2) (2015).
[15] O. Balli, Advanced exergy analyses of an aircraft turboprop engine (TPE), Energy, 124 (2017) 599-612.
[16] Y. Li, J. Ming, Y. Chang, S.L. Kokjohn, R.D. Reitz, Thermodynamic energy and exergy analysis of three different engine combustion regimes, Applied Energy, 180 (2016) 849-858.
[17] B. Dogan, D. Erol, H. Yaman, E. Kodanli, The effect of ethanol-gasoline blends on performance and exhaust emissions of a spark ignition engine through exergy analysis, Applied Thermal Engineering, 120 (2017) 433-443.
[18] H. Feng, D. Liu, X. Yang, M. An, W. Zhang, W. Zhang, Availability analysis of using iso-octane/n-butanol blends in spark-ignition engines, Renewale Energy, 96 (2016) 281-294.
 
 
 
 
[19] G. Irvin, Y. Richard, Combustion, California: Academic Press, 2008.
[20] J.B. Heywood, Internal combustion engine fundamentals, Mcgraw-hill New York, 1988.
[21] E. Ollivier, Contribution to the characterization of heat transfer in spark ignition engines, Application to knock detection, Ph. D. thesis, ENSTIM de Nantes, France, 2006.
[22] J. Chang, O. Güralp, Z. Filipi, D.N. Assanis, T.-W. Kuo, P. Najt, R. Rask, New heat transfer correlation for an HCCI engine derived from measurements of instantaneous surface heat flux, 0148-7191, SAE Technical Paper, 2004.
[23] G. Eichelberg, Some new investigations on old combustion engine problems, Engineering, 148 (1939) 547-550.
[24] W. Annand, Heat transfer in the cylinders of reciprocating internal combustion engines, Proceedings of the Institution of Mechanical Engineers, 177(1) (1963) 973-996.
[25] G. Sitkei, G. Ramanaiah, A rational approach for calculation of heat transfer in diesel engines, 0148-7191, SAE Technical Paper, 1972.
[26] G.F. Hohenberg, Advanced approaches for heat transfer calculations, 0148-7191, SAE Technical Paper, 1979.
[27] G. Borman, K. Nishiwaki, Internal-combustion engine heat transfer, Progress in energy and combustion science, 13(1) (1987) 1-46.
[28] M.S. Lounici, K. Loubar, M. Balistrou, M. Tazerout, Investigation on heat transfer evaluation for a more efficient two-zone combustion model in the case of natural gas SI engines, Applied Thermal Engineering, 31(2) (2011) 319-328.
[29] I. Sezer, I. Altin, A. Bilgin, Exergetic Analysis of Using Oxygenated Fuels in Spark-Ignition (SI) Engines, Energy & Fuels, 23 (2009) 1801-1807.
[30] K. Wark, Advanced Thermodynamics for Engineers, New York: McGraw-Hill, 1994.
[31] P. Shayler, S. May, T. Ma, The determination of heat transfer from the combustion chambers of SI engines, 0148-7191, SAE Technical Paper, 1993.
نشریه مهندسی مکانیک امیرکبیر
دوره 51، شماره 4
مهر و آبان 1398
صفحه 61-70

فایل ها

هم رسانی

ارجاع به این مقاله

آمار