Two-Phase Numerical Modelling of a Wet Exhaust System in a Catamaran Motor Yacht Diesel Engine

Year 2021, Issue: 31, 165 - 170, 31.12.2021

Alihan Cambaz Yasin Furkan Görgülü Halit Arat

https://doi.org/10.31590/ejosat.1007351

Cited By: 1

Abstract

In this study, the multiphase temperature distributions and volume fractions through wet exhaust system were investigated as 3D by using comprehensive numerical model in a yacht diesel engine. For this purpose, Volume of Fluid multiphase model was selected as the numerical model. Fuel exhausts are generally located underwater to ensure a modern yacht appearance and minimize exhaust noise. To manage water pressure, exhaust gases, and cooling water flow distribution, a scoop is positioned above the catamaran yacht exhaust. Besides, two types of fluids have been used one of which is the hot exhaust gas the other one is the cooling water used in the nozzle. The design has been created using Ansys SpaceClaim and the cooling water is sprayed from the 60° tip of the nozzle. Moreover, the mesh used in the simulation has 1,405,113 elements and 523,125 nodes and the average mesh skewness is 0.46, the average orthogonal quality of the mesh is 0.64. Realizable k-ε turbulence model has been used in the simulations. According to results, the flow fully develops after the time of 1.5 seconds and the water nozzle sprays the water along the tube cools the exhaust gases. Also, the stagnation points occurring at the elbow fitting of the tube are striking when the velocity contours and velocity vectors are examined.

Keywords

Wet exhaust system, Marine diesel engine, CFD, Thermal performance, Two-phase flow.

Thanks

The authors would like to express their appreciation to “SU Ar-Ge Dizayn ve Mühendislik A.Ş.” for their assistance throughout the study. The authors declare that they have no conflict of interest. Also, the research presented in the manuscript did not receive any external funding.

Bir Katamaran Motoryat Dizel Motorunda Bir Islak Egzoz Sisteminin İki Fazlı Sayısal Modellenmesi

Abstract

Bu çalışmada, bir yat dizel motorunda kapsamlı sayısal model kullanılarak ıslak egzoz sisteminden çok fazlı sıcaklık dağılımları ve hacim fraksiyonları 3 boyutlu olarak incelenmiştir. Bu amaçla sayısal model olarak Volume of Fluid çok fazlı modeli seçilmiştir. Yakıt egzozları, modern bir yat görünümü sağlamak ve egzoz gürültüsünü en aza indirmek için genellikle su altında bulunmaktadır. Su basıncını, egzoz gazlarını ve soğutma suyu akış dağıtımını yönetmek için katamaran yat egzozunun üzerine bir muhafaza yerleştirilmiştir. Bununla birlikte, nozulda kullanılan sıcak egzoz gazı ve soğutma suyu olmak üzere iki tip akışkan kullanılmıştır. Tasarım Ansys SpaceClaim kullanılarak oluşturulmuştur ve soğutma suyu nozulun 60° ucundan püskürtülecek şekilde ele alınmıştır. Dahası simülasyonda kullanılan yapısal ağ 1.405.113 elemana ve 523.125 düğüme sahiptir ve ortalama yapısal ağın çarpıklığı 0,46, meshin ortalama ortogonal kalitesi 0,64'tür. Simülasyonlarda Realizable k-ε türbülans modeli kullanılmıştır. Sonuçlar incelendiğinde, 1,5 saniye sonra akış tam olarak gelişmekte ve su nozulu, suyu boru boyunca püskürtmekte ve egzoz gazlarını soğutmaktadır. Ayrıca hız konturları ve hız vektörleri incelendiğinde borunun dirsek bağlantı noktasında meydana gelen durma noktaları dikkat çekicidir.

Keywords

Islak egzoz sistemi, Deniz dizel motoru, CFD, Termal performans, İki fazlı akış.

References

• AB Marine. (n.d.). Dry and wet exhaust. - AB Marine service. Retrieved September 9, 2021, from https://ab-marineservice.com/en/dry-and-wet-exhaust/
• Ansys Inc. (2011). Introduction to Ansys Meshing (pp. L5-16). Ansys Inc.
• Arat, H., Arslan, O., Ercetin, U., & Akbulut, A. (2021). A comprehensive numerical investigation of unsteady-state two-phase flow in gravity assisted heat pipe enclosure. Thermal Science and Engineering Progress, 25. https://doi.org/10.1016/j.tsep.2021.100993
• Aydın, H., & İlkılıç, C. (2017). Air pollution, pollutant emissions and harmfull effects. Journal of Engineering and Technology, 1(1), 8–15.
• Bardina, J. E., Huang, P. G., & Coakley, T. J. (1997). Turbulence modeling validation. 28th Fluid Dynamics Conference, April. https://doi.org/10.2514/6.1997-2121
• Blasco, J., Durán-Grados, V., Hampel, M., & Moreno-Gutiérrez, J. (2014). Towards an integrated environmental risk assessment of emissions from ships’ propulsion systems. Environment International, 66. https://doi.org/10.1016/j.envint.2014.01.014
• Femto Engineering. (n.d.). Case study: CFD Simulation of an underwater yacht exhaust - Femto Engineering -.
• Fernoaga, V., Sandu, V., & Balan, T. (2020). Artificial intelligence for the prediction of exhaust back pressure effect on the performance of diesel engines. Applied Sciences (Switzerland), 10(20). https://doi.org/10.3390/app10207370
• Foteinos, M. I., Christofilis, G. I., & Kyrtatos, N. P. (2020). Response of a direct-drive large marine two-stroke engine coupled to a selective catalytic reduction exhaust aftertreatment system when operating in waves. Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment, 234(3). https://doi.org/10.1177/1475090219899543
• GORGULU, Y. F., OZGUR, M. A., & KOSE, R. (2021). CFD analysis of a NACA 0009 aerofoil at a low reynolds number. Journal of Polytechnic, 0900, 0–1. https://doi.org/10.2339/politeknik.877391
• Guerrero, E., Muñoz, F., & Ratkovich, N. (2017). Comparison between eulerian and vof models for two-phase flow assessment in vertical pipes. CTyF - Ciencia, Tecnologia y Futuro, 7(1), 73–84. https://doi.org/10.29047/01225383.66
• Hao, C., Zhang, C., Zhang, J., Wu, J., Yue, Y., & Qian, G. (2022). An efficient strategy to screen an effective catalyst for NOx-SCR by deducing surface species using DRIFTS. Journal of Colloid and Interface Science, 606, 677–687. https://doi.org/10.1016/J.JCIS.2021.08.070
• Lee, Y., Lee, S., Lee, S., Choi, H., & Min, K. (2021). Characteristics of NOx emission of light-duty diesel vehicle with LNT and SCR system by season and RDE phase. Science of the Total Environment, 782, 146750. https://doi.org/10.1016/j.scitotenv.2021.146750
• M, A., & Tomar, G. (2021). Interface reconstruction and advection schemes for volume of fluid method in axisymmetric coordinates. Journal of Computational Physics, 110663. https://doi.org/10.1016/j.jcp.2021.110663
• Magnusson, M., Fridell, E., & Härelind, H. (2016). Improved low-temperature activity for marine selective catalytic reduction systems. Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment, 230(1). https://doi.org/10.1177/1475090214536546
• MarQuip B.V. (n.d.). Engineering techniques - MarQuip B.V. Exclusive Yacht exhausts. Retrieved September 9, 2021, from https://marquip.nl/engineering-techniques/
• Nesbitt, T. S., Arevalo, J. A., Tanji, J. L., Morgan, W. A., & Aved, B. (1992). Will family physicians really return to obstetrics if malpractice insurance premiums decline? The Journal of the American Board of Family Practice / American Board of Family Practice, 5(4), 413–418. https://doi.org/10.3122/jabfm.5.4.413
• Prosperetti, A., & Tryggvason, G. (2007). Computational Methods for Multiphase Flow (Vol. 148). Cambridge University Press.
• Ryu, Y., Kim, T., Kim, J., & Nam, J. (2020). Marine Science and Engineering Investigation on the Emission Characteristics with a Wet-Type Exhaust Gas Cleaning System for Marine Diesel Engine Application. Journal of Marine Science and Engineering, 8(11), 850. https://doi.org/10.3390/jmse8110850
• Sapra, H. D., Singh, J., Dijkstra, C., de Vos, P., & Visser, K. (2020). Experimental investigations of marine diesel engine performance against dynamic back pressure at varying sea-states due to underwater exhaust systems. ASME 2019 Internal Combustion Engine Division Fall Technical Conference, ICEF 2019. https://doi.org/10.1115/ICEF2019-7216
• Sapra, H., Godjevac, M., Visser, K., Stapersma, D., & Dijkstra, C. (2017). Experimental and simulation-based investigations of marine diesel engine performance against static back pressure. Applied Energy, 204. https://doi.org/10.1016/j.apenergy.2017.06.111
• SimScale. (n.d.). K-epsilon Turbulence Model | Global Settings. https://www.simscale.com/docs/simulation-setup/global-settings/k-epsilon/
• Tryggvason, G., Scardovelli, R., & Zaleski, S. (2003). Direct numerical simulations of multiphase flow. In Multiphase Science and Technology (Vol. 15, Issues 1–4). https://doi.org/10.1615/MultScienTechn.v15.i1-4.190
• Wang, M., Zhang, H., & Gong, W. (2019). Research on airflow uniformity of marine selective catalytic reduction reverse blow system. The Journal of Engineering, 2019(23), 9083–9087. https://doi.org/10.1049/JOE.2018.9190
• Wang, X. C., Klemeš, J. J., Dong, X., Fan, W., Xu, Z., Wang, Y., & Varbanov, P. S. (2019). Air pollution terrain nexus: A review considering energy generation and consumption. Renewable and Sustainable Energy Reviews, 105(December 2018), 71–85. https://doi.org/10.1016/j.rser.2019.01.049
• West Marine. (n.d.). Exhaust System Basics. Retrieved September 9, 2021, from https://www.westmarine.com/WestAdvisor/Exhaust-System-Basics
• Zeng, L. (2021). 25-Meter catamaran. https://grabcad.com/library/25-meter-catamaran-2
• Zhu, Y., Li, T., Xia, C., Feng, Y., & Zhou, S. (2020). Simulation analysis on vaporizer/mixer performance of the high-pressure SCR system in a marine diesel. Chemical Engineering and Processing - Process Intensification, 148. https://doi.org/10.1016/j.cep.2020.107819