Effects of Different Turbulence Models on Hydrodynamic Performance of Circular and Square Section Scrubbers

Öz

In this study, wet venturi-type gas scrubbers are examined and the effects of various turbulence models on the hydrodynamic performance of two identical square and circular cross-section gas scrubbers were investigated using the Computational Fluid Dynamics (CFD) method. Verification and validation studies were conducted, and the results were successfully compared with numerical and experimental data obtained from the literature. Then, the collection efficiency, pressure drop, and velocity distributions of gas scrubbers with two different cross-sectional geometries were compared, and the performances of k- (Standard, Realizable, and RNG) and k- (Standard and SST) in venturi gas scrubbers were comparatively presented. It was demonstrated that the Realizable k-epsilon turbulence model performed better than the other models in terms of droplet collection efficiency; however, all models yielded similar results in predicting pressure distributions. Among the identical gas scrubbers with circular and square cross-sections, the former exhibited higher velocity and consequently lower pressure distributions. However, it was concluded that the droplet collection efficiency of the square cross-section gas scrubber was 53% higher than that of the circular one.

Anahtar Kelimeler

• Wet venturi scrubbers
• Collection efficiency
• Circular scrubber
• Square scrubber
• Turbulence models

Farklı Türbülans Modellerinin Daire ve Kare Kesitli Gaz Yıkayıcıların Hidrodinamik Performansları Üzerindeki Etkileri

Öz

Bu çalışmada, ıslak venturi tipi gaz temizleyiciler ele alınarak farklı türbülans modellerinin özdeş kare ve daire kesitli gaz temizleyicilerin hidrodinamik performansları üzerindeki etkileri Hesaplamalı Akışkanlar Dinamiği (HAD) metodu kullanılarak incelenmiştir. Verifikasyon ve doğrulama çalışmaları yapılarak sonuçlar literatürdeki sayısal ve deneysel verilerle başarılı bir şekilde mukayese edilmiştir. Daha sonra iki farklı kesit geometrisine sahip gaz temizleyicilerin toplama verimi, basınç düşüşü ve hız dağılımları mukayese edilerek k-epsilon (Standart, Realizable ve RNG) ve k- (Standart ve SST) türbülans modellerinin venturi gaz temizleyicilerdeki performansları birbirleri ile karşılaştırmalı olarak sunulmuş ve damlacık toplama verimi açısından Realizable k- türbülans modelinin diğer modellere nazaran daha başarılı olduğu ancak basınç dağılımlarını tahmininde tüm bu modellerin birbirlerine yakın bir sonuçlar verdiği gösterilmiştir. Mukayese edilen daire ve kare kesitli özdeş gaz temizleyicilerden birincisinde daha yüksek hız ve dolayısıyla daha düşük basınç dağılımları elde edildiği ancak kare kesitli gaz temizleyicinin damlacık toplama veriminin dairesel kesitli olana nazaran %53 ile daha yüksek olduğu sonucuna varılmıştır.

Anahtar Kelimeler

• Islak venturi tipi gaz temizleyiciler
• Toplama verimi
• Daire kesitli gaz temizleyici
• Kare kesitli gaz temizleyici
• Türbülans modelleri

Kaynakça

1. Hava Kirliliği ve Sağlık Etkileri-Kara rapor, Temiz Hava Hakkı Platformu” 2019.
2. Guerra, V.G., Béttega, R., Gonçalves, J.A.S., Coury, J.R, (2012). Pressure drop and liquid distribution in a venturi scrubber: Experimental data and CFD simulation. Ind Eng Chem Res, 51(23), 8049–8060.
3. Yang, S., Zhao, X., Sun, W., Yuan, J., Wang, Z, (2019). Effect of ring baffle configuration in a self-priming venturi scrubber using CFD simulations. Particuology, 47, 63–69.
4. Giroth, E.J., Ang, E.B, (2022). The design and evaluation of exhaust gas cleaning system equipped with SOx scrubber,” 2022 IEEE 13th International Conference on Mechanical and Intelligent Manufacturing Technologies, Cape Town, South Africa.
5. Bal, M., Meikap, B.C, (2017). Prediction of hydrodynamic characteristics of a venturi scrubber by using CFD simulation, S Afr J Chem Eng, 24, 222–231.
6. Brown, K., Kalata, W., Schick, R, (2014). Optimization of SO2 scrubber using CFD modeling, Procedia Engineering, 170–180.
7. Joni, J., Tambing, E., Siregar, S.P., Setiawan, R.P.A., Tambunan, A.H., Siregar, K, (2023). Evaluating the application of bubble wet scrubber systems for gas cleaning in gasification, Instrumentation Mesure Metrologie, 22(1), 21–27
8. Wang, S.C., Gabriela, D, (2022). Filtering analysis of a wet scrubber with computational fluid dynamics simulation. IEEE 4th Eurasia Conference on IOT, Communication and Engineering (ECICE), Yunlin, Taiwan

9. Guerra, V.G., Gonçalves, J.A.S., Coury, J.R, (2008). Experimental investigation on the effect of liquid injection by multiple orifices in the formation of droplets in a Venturi scrubber. J Hazard Mater. 161(1), 351–359.
10. Luan, Z., Liu, X., Zheng, M., Zhu, L, (2017). Numerical simulation of square section venturi scrubber with horizontal spray, Procedia Computer Science, 107, 117–121.
11. Ali, M., Yan, C., Sun, Z., Wang, J., Gu, H, (2013). CFD simulation of dust particle removal efficiency of a venturi scrubber in CFX. Nuclear Engineering and Design, 256, 169–177.
12. Ulas, A. (2006). Passive flow control in liquid-propellant rocket engines with cavitating venturi. Flow Measurement and Instrumentation, 17(2), 93–97.
13. Manzano, J., Palau, C.V., De Azevedo, B.M., Do Bomfim, G.D., Vasconcelos, D.V, (2016). Geometry and head loss in venturi injectors through computational fluid Dynamics. J Brazilian Association of Agricultural Engineering, 3, 482–491.
14. O’Hern, H., Murphy, T., Zhang, X., Liburdy, J., Abbasi, B. A, (2022). Design method for low-pressure venturi nozzles, Applied Mechanics, 3(2), 390–411.
15. Wilson, D.A, Pun, K., Ganesan, P.B., Hamad, F, (2021). Geometrical optimization of a venturi-type microbubble generator using CFD simulation and experimental measurements. Design, 5(1), 4.
16. Shi, H., Li, M., Nikrityuk, P., Liu, Q, (2019). Experimental and numerical study of cavitation flows in venturi tubes: From CFD to an empirical model. Chem Eng Sci, 207, 672–687.
17. Silva, A.M., (2008). Numerical and Experimental Study of Venturi Scrubbers, PhD thesis, Universidade do Minho, Portugal.
18. Xu, Y., Zhao, Y., Long, Z, (2012). Study on the key factors of wet gas metering overreading in standard venturi tube base on DPM. Applied Mechanics and Materials, 220-223, 1693–1697.
19. Atmaca, M., Cetin, B., Ezgi, C., Kosa, E, (2021). CFD analysis of jet flows ejected from different nozzles. International Journal of Low-Carbon Technologies, 16(3), 940–945.
20. Luan, Z., Liu, X., Zheng, M., Zhu, L, (2016) Numerical simulation of square section venturi scrubber with horizontal spray. Procedia Computer Science, 107, 117-121.
21. Turkoglu, F., Bayraktar, S, (2023). Effects of the Nozzle Location on Hydrodynamic Properties of a Venturi- Type Scrubber. International conference on innovative academic studies, 3(1),107-111.
22. Turkoglu, S., Bayraktar, S, (2024). Kara ve Denizcilik Sektöründe Kullanılan Gaz Temizleyiciler (Scrubbers) Hakkında Literatür İncelenmesi. The 3rd International Congress on Ship and Marine Technology (GMO-SHIPMAR 2024) Trabzon, Turkey.
23. ASME, (2005). Measurement of fluid flow in pipes using orifice, nozzle, and venturi. The American Society of Mechanical Engineers. MFC-3M-2004; United Engineering Center: New York, NY, USA.
24. Baylar, A., Aydin, M.C., Unsal, M., Ozkan, F, (2009). Numerical modeling of venturi flows for determining air ınjection rates using Fluent V6.2. Math. Comput. Appl. 14, 97-108.
25. Majumdar, P, (2022). Computational fluid dynamics and heat transfer, 2nd Edition, CRC Press.
26. Ansys Inc, (2018). ANSYS Fluent Tutorial Guide.
27. Ansys Inc, (2016). ANSYS Fluent Tutorial Guide.
28. Bolek, A., Bayraktar, (2019). Flow and heat transfer investigation of a circular jet issuing on different types of surfaces. Sadhana, 44, 242.
29. Brunhart, M., Soteriou, C., Gavaises, M., Karathanassis, I, (2020). Investigation of cavitation and vapor shedding mechanisms in a venturi nozzle. Physics of Fluids, 32(8), Article 083306.
30. Zahari, N.M., Zawawi, M.H., Sidek, L.M., Mohammad, D., Itam, Z., Ramli, M.Z., Syamsir, A., Abas, A., Rashid, M, (2018). Introduction of discrete phase model (DPM) in fluid flow: A review,” AIP Conference Proceedings, 2030 (1).
31. Khadra, H., Kouider, R., Tayeb, N.T., Al-Kassir, A., Carrasco-Amador, J.P, (2022). Numerical Simulation of the Cleaning Performance of a Venturi Scrubber. Energies, 15(4), 1531.