Homojen Dolgulu Sıkıştırma Ateşlemeli Bir Motorda Supap Profili Optimizasyonu

Öz

İçten yanmalı motorların giderek sıkılaşan emisyon standartları dolayısıyla, farklı konseptlerle yanma gerçekleştirilmesi ve emisyonlarının azaltılması amaçlanmaktadır. Homojen dolgulu sıkıştırma ateşlemeli motorlarda, görece düşük sıcaklıklarda yanma meydana geldiğinden dolayı, çok düşük NOX ve is emisyonları açığa çıkmaktadır. Ancak yanma prosesi, vuruntusuz ve teklemesiz olarak gerçekleşebilmesi için motorun iyi bir şekilde kontrol edilmesi ve bütün parametrelerinin optimize edilmesi gerekmektedir. Bu çalışmada, homojen dolgulu sıkıştırma ateşlemeli dizel yakıtlı bir motorun, bu yeni nesil yanma stratejisine uygun olarak supap profili bir boyutlu yanma modeli ve genetik algoritma kullanılarak optimize edilmiştir. Supap açılma ve kapanma krank açıları parametrik olarak değiştirilmiştir. Ayrıca, supap profilinin tamamen açıldığı noktaya bekleme eklenmiştir. Böylelikle, volümetrik verim artışı hedeflenmiş ve fren gücü değeri maksimize edilmiştir. Tasarlanan yeni supap profili ile motor fren gücü %28 artarken, özgül yakıt tüketimi değeri %6 azalmıştır.

Anahtar Kelimeler

• Homojen Dolgulu
• sıkıştırma ateşlemeli
• optimizasyon
• supap profili
• genetik algoritma

Optimization of Valve Profile for a Homogeneous Charge Compression Ignition Engine

Öz

It is aimed to occur combustion with different concepts to decrease emissions, due to the increasingly stringent emission standards of internal combustion engines. Since combustion occurs at relatively low temperatures in a homogeneous charged compression ignition (HCCI) engines, NOX and soot emissions emit a very low level. However, in order for the combustion process to be carried out without knock and misfire, the HCCI engine must be well controlled, and all engine parameters must be optimized. In this study, the valve profile of an HCCI diesel engine has been optimized using a one-dimensional combustion model and genetic algorithm in accordance with this combustion strategy. Valve opening and closing timings have been changed parametrically. In addition, the dwell angle has been added to the point where the valve profile is fully opened. Thus, the volumetric efficiency increase was targeted, and brake power was maximized. With the newly implemented valve profile, engine brake power increased by 28%, while brake specific fuel consumption value decreased by 6%.

Anahtar Kelimeler

• Homogeneous charge
• compression-ignition engine
• optimization
• valve profile
• genetic algorithm

Kaynakça

1. Nilsen CW, Biles DE, Mueller CJ. Using Ducted Fuel Injection to Attenuate Soot Formation in a Mixing-Controlled Compression Ignition Engine. SAE International Journal of Engines 2019;12:3–12. https://doi.org/10.4271/03-12-03-0021.
2. Sener R, Yangaz MU, Gul MZ. Effects of injection strategy and combustion chamber modification on a single-cylinder diesel engine. Fuel 2020;266. https://doi.org/10.1016/j.fuel.2020.117122.
3. Chen Y, Li X, Li X, Zhao W, Liu F. The wall-flow-guided and interferential interactions of the lateral swirl combustion system for improving the fuel/air mixing and combustion performance in DI diesel engines. Energy 2019;166:690–700. https://doi.org/10.1016/j.energy.2018.10.107.
4. Chaudhari VD, Deshmukh D. Diesel and diesel-gasoline fuelled premixed low temperature combustion (LTC) engine mode for clean combustion. Fuel 2020;266:116982. https://doi.org/10.1016/j.fuel.2019.116982.
5. Anarghya A, Rao N, Nayak N, Tirpude AR, Harshith DN, Samarth BR. Optimized ANN-GA and experimental analysis of the performance and combustion characteristics of HCCI engine. Applied Thermal Engineering 2018;132:841–68. https://doi.org/10.1016/j.applthermaleng.2017.12.129.
6. Fiveland SB, Assanis DN. A four-stroke homogeneous charge compression ignition engine simulation for combustion and performance studies. SAE Technical Papers 2000.
7. Tian G, Wang Z, Ge Q, Wang J, Shuai S. Mode switch of SI-HCCI combustion on a GDI engine. SAE Technical Papers 2007;2007. https://doi.org/10.4271/2007-01-0195.
8. Hairuddin AA, Wandel AP, Yusaf T. An Introduction to a Homogeneous Charge Compression Ignition Engine. Journal of Mechanical Engineering and Sciences 2014;7:1042–52.

9. Song HH, Edwards CF. Optimization of recompression reaction for low-load operation of residual-effected HCCI. SAE Technical Papers 2008;2008:776–90. https://doi.org/10.4271/2008-01-0016.
10. Çinar C, Uyumaz A. Homojen Dolgulu Sıkıştırma ile Ateşlemeli Bir Benzin Motoru için Kam Tasarımı ve İmalatı. Journal of the Faculty of Engineering and Architecture of Gazi University 2014;29:15–22.
11. Ma H, Xu H, Wang J, Schnier T, Neaves B, Tan C, et al. Model-Based Multiobjective Evolutionary Algorithm Optimization for HCCI Engines. IEEE Transactions on Vehicular Technology 2015;64:4326–31. https://doi.org/10.1109/TVT.2014.2362954.
12. Hunicz J, Mikulski M, Geca MS, Rybak A. An applicable approach to mitigate pressure rise rate in an HCCI engine with negative valve overlap. Applied Energy 2020;257:1–14. https://doi.org/10.1016/j.apenergy.2019.114018.
13. Gamma Technologies. GT-Suite Engine Performance Application Manual. Westmont, USA: Gamma Technologies; 2016.
14. Patel A, Kong SC, Reitz RD. Development and validation of a reduced reaction mechanism for HCCI engine simulations. SAE Technical Papers 2004;2004. https://doi.org/10.4271/2004-01-0558.
15. Hadka D, Reed P. Large-scale parallelization of the Borg multiobjective evolutionary algorithm to enhance the management of complex environmental systems. Environmental Modelling & Software 2015;69:353–69. https://doi.org/10.1016/j.envsoft.2014.10.014.
16. Deb K, Jain H. An Evolutionary Many-Objective Optimization Algorithm Using Reference-Point-Based Nondominated Sorting Approach, Part I: Solving Problems With Box Constraints. IEEE Transactions on Evolutionary Computation 2014;18:577–601. https://doi.org/10.1109/TEVC.2013.2281535.