Metal Süngere Kanatçık Eklenmesinin Hava Ve Su Akışkanları İle Isı Transferine Etkisinin Sayısal Yöntemlerle İncelenmesi

Year 2024, EARLY VIEW, 1 - 1

Orkun Dogu , Abdullah Berkan Erdoğmuş , İlhami Horuz

https://doi.org/10.2339/politeknik.1573451

Abstract

Teknolojideki ilerlemeler ile birlikte ısı üreten elektronik ekipmanların boyutlarındaki küçülmelere rağmen işlevlerinin artmasından kaynaklı birim hacim ısı yükleri sürekli bir artış göstermektedir. Artan ısı yüklerine bağlı olarak soğutma performanslarının iyileştirilmesi önem kazanmaktadır. Metal süngerler çok yüksek yüzey/hacim oranları ile ısı transferini iyileştirmede kullanılabilecek yöntemler arasında öne çıkan uygulamalardan biridir. Yüksek porozite, su gibi ısı transfer özellikleri yüksek bir akışkan için ısının metal süngerin yüksekliği boyunca iletiminin sağlanmasında sorun teşkil etmektedir. Bu sebeple metal süngerin yüksekliği boyunca ısı iletiminin sağlanması ve ısıtılan yüzeyin Nu sayısının yükseltilebilmesi için metal süngerlerin kanatlarla birleştirilmesi literatürde incelenmiştir. Bu çalışmanın literatürdeki çalışmalardan farkı metal sünger ile kanatçık kullanımın etkisinin büyük ısıl iletkenliğe sahip bir akışkan (su) ve küçük ısıl iletkenliğe sahip bir akışkan (hava) ile ayrı ayrı kullanılmış olmasıdır. Metal süngerler Hesaplamalı Akışkanlar Dinamiği (HAD) yazılımlarında poroz ortam parametreleri kullanılarak modellenebilmektedir. Metal sünger alüminyum malzemeden üretilmiş olup yüksek poroziteye (%90) sahiptir. Çalışmada kanat sayısı da bir parametre olarak incelenmiş olup, kanat sayısının bu iki sıvının ısı tanımlanan yüzeydeki Nu sayısını nasıl etkilediği ANSYS Fluent yazılımı ile incelenmiştir. Çalışmada akışkan hava olduğu durumda kanat eklenmesinin verimliliği artan hava hızı ile artarken duvardaki sıcaklık artışı %43’e kadar, akışken su olduğu durumda ise kanat eklenmesinin verimliliği artan su hızı ile azalırken duvardaki sıcaklık artışı %48’e kadar azaltılabildiği gözlemlenmiştir.

Keywords

Sıvı soğutma, metal sünger, hesaplamalı akışkanlar dinamiği, poroz ortamlarda ısı geçişi

Numerical Investigation of the Effect of Fins Added to Metal Foam on Heat Transfer Using Air and Water Coolants

Abstract

Advancements in technology have led to a continuous increase in the amount of heat generated within electronic equipment, despite the reduction in their size and the increase in their functionalities. Due to the escalating heat loads, enhancing cooling performance has become more critical in applications. Metal foams have recently emerged as a prominent method to enhance heat transfer in cooling systems, primarily due to their great surface-to-volume ratios. However, the issue arises when high porosity values are involved, particularly when a high thermal conductivity fluid such as water is used, as it presents difficulty in ensuring heat conduction along the height of the metal foam. Consequently, integrating fins with metal foams has been documented in the literature as a means to increase the Nusselt number on the heated surface. In this study, in contrast to the existing literature, the effect of using metal foam combined with fins was examined with two separate fluids possessing dissimilar thermal conductivities: a high thermal conductivity fluid (water) and a low thermal conductivity fluid (air). The metal foams were modeled using Computational Fluid Dynamics (CFD) software with porous medium parameters. The metal foam used is made of aluminum material and exhibits a high porosity level of 90%. Additionally, the impact of varying the number of fins was investigated as a parameter, and its effect on the heat transfer from the heated surfaces for both fluids was examined using ANSYS Fluent software. In the study, it was observed that when air is used as the fluid, the addition of fins increases efficiency with increasing air velocity, while the temperature rise on the wall can be reduced by up to 43%. Conversely, when water is used as the fluid, the addition of fins decreases efficiency with increasing water velocity, yet the temperature rise on the wall can be reduced by up to 48%.

Keywords

Liquid cooling, metal foams, computational fluid dynamics, heat transfer in porous media

References

• [1] Hunt, M.L., Tien, C.L., “Effects on thermal dispersion on forced convection in fibrous media” International Journal of Heat and Mass Transfer, 31, 301-309, (1988).
• [2] Calmidi, V.V., “Transport Phenomena in High Porosity Metal Foams”, Ph.D. Thesis, University of Colorado, USA, (1998).
• [3] Calmidi, V.V., Mahajan, R.L., “The effective thermal conductivity of high porosity fibrous metal foams”, Journal of Heat Transfer, 121, 466-471, (1999).
• [4] Calmidi, V.V., Mahajan, R.L., “Forced convection in high porosity metal foams”, Journal of Heat Transfer, 122, 557-565, (2000).
• [5] Boomsma, K., Poulikakos, D., Zwick, F., “Metal foam as compact high performance heat exchangers”, Mechanics of Materials, 3, 68-75, (2003).
• [6] DeGroot, C.T., Straatman, A.G., Betchen, L.J., “Modeling Forced Convection in Finned Metal Foam Heat Sinks”, Journal of Electronic Packaging, 131(2), (2009).
• [7] Guarino, S., Rubino, G., Tagliaferri, V., Ucciardello, N., “Thermal behavior of open cell aluminum foams in forced air: Experimental analysis”, Measurement, 60, 97-103, (2015).
• [8] Ranut, P., “On the effective thermal conductivity of aluminum metal foams: Review and improvement of the available empirical and analytical models”, Applied Thermal Engineering, 101, 496-524, (2016).
• [9] Mahjoob, S., Vafai, K., “A synthesis of fluid and thermal transport models for metal foam heat exchangers”, International Journal of Heat and Mass Transfer, 51, 3701-3711, (2008).
• [10] Zhao, C.Y., “Review on thermal transport in high porosity cellular metal foams with open cells”, International Journal of Heat and Mass Transfer, 55, 3618-3632, (2012).
• [11] Mancin, S., Zilio, C., Rosetto, L., Cavallini A., “Foam height effects on heat transfer performance of 20 ppi aluminum foams”, Applied Thermal Engineering, 49, 55-60, (2012).
• [12] Kim, D.Y., Sung T.H., Kim K.C., “Application of metal foam heat exchangers for a high-performance liquefied natural gas regasification system”, Energy, 105, 57-69, (2016).
• [13] Bayomy, A.M., Saghir, M.Z., Yousefi, T., “Electronic cooling using water flow in aluminum metal foam heat sink: Experimental and numerical approach”, International Journal of Thermal Sciences, 109, 182-200, (2016).
• [14] Kemerli, U., Hücresel Metalik Yapılarda Akış ve Isı Transfer Karakteristikleri, Ph.D. Thesis, Trakya University, (2020).
• [15] Angirasa, D., “Forced Convective Heat Transfer in Metallic Fibrous Materials”, Journal of Heat Transfer, 124(4), 739-745, (2002).
• [16] Odabaee, M., Mancin, S., Hooman, K., “Metal foam heat exchangers for thermal management of fuel cell systems – An experimental study”, Experimental Thermal and Fluid Science, 51(0), 214-219, (2013).
• [17] Bhattacharya, A., & Mahajan, R. L., “Metal Foam and Finned Metal Foam Heat Sinks for Electronics Cooling in Buoyancy-Induced Convection”, Journal of Electronic Packaging, 128(3), 259, (2006).
• [18] Chen, X., Tavakkoli, F., & Vafai, K., “Analysis and Characterization of Metal Foam-Filled Double-Pipe Heat Exchangers”, Numerical Heat Transfer, 68(10), 1031-1049, (2015).
• [19] Dai, Z., Nawaz, K., Park, Y., Chen, Q., & Jacobi, A. M., “A Comparison of Metal-Foam Heat Exchangers to Compact Multilouver Designs for Air-Side Heat Transfer Applications”, Heat Transfer Engineering, 33(1), 21-30, (2012).
• [20] De Jaeger, P., T’Joen, C., Huisseune, H., Ameel, B., De Schampheleire, S., De Paepe, M., “Assessing the influence of four bonding methods on the thermal contact resistance of open-cell aluminum foam”, International Journal of Heat and Mass Transfer, 55(21-22), 6200, (2012).
• [21] Dukhan, N., “Correlations for the pressure drop for flow through metal foam.”, Experiments in Fluids, 41(4), 665-672, (2006).
• [22] Feng, S. S., Kuang, J. J., Wen, T., Lu, T. J., Ichimiya, K., “An experimental and numerical study of finned metal foam heat sinks under impinging air jet cooling”, International Journal of Heat and Mass Transfer, 77, 1063-1074, (2014).
• [23] Dukhan, N., Bağcı, Ö., Özdemir, M., “Thermal development in open-cell metal foam: An experiment with constant wall heat flux”, International Journal of Heat and Mass Transfer, 85, 852-859, (2015).
• [24] Edouard, D., Lacroix, M., Huu, C. P., Luck, F., “Pressure drop modeling on SOLID foam: State-of-the art correlation”, Chemical Engineering Journal, 144(2), 299-311, (2008).
• [25] Hetsroni, G., Gurevich, M., Rozenblit, R., “Natural convection in metal foam strips with internal heat generation”, Experimental Thermal and Fluid Science, 32(8), 1740-1747, (2008).
• [26] Kathare, V., Davidson, J. H., Kulacki, F. A., “Natural convection in water-saturated metal foam”, International Journal of Heat and Mass Transfer, 51(15-16), 3794-3802, (2008).
• [27] Kim, S. Y., Paek, J. W., Kang, B. H., “Flow and Heat Transfer Correlations for Porous Fin in a Plate-Fin Heat Exchanger”, Journal of Heat Transfer, 122(3), 572-578, (2000).
• [28] Mahjoob, S., Vafai, K., “A synthesis of fluid and thermal transport models for metal foam heat exchangers”, International Journal of Heat and Mass Transfer, 51(15-16), 3701-3711., (2008).
• [29] Mancin, S., Zilio, C., Cavallini, A., Rossetto, L., “Pressure drop during air flow in aluminum foams”, International Journal of Heat and Mass Transfer, 53(15-16), 3121-3130, (2010).
• [30] Mancin, S., Zilio, C., Rossetto, L., Cavallini, A., “Heat Transfer Performance of Aluminum Foams”, Journal of Heat Transfer, 133(6), 060904, (2011).
• [31] Mancin, S., Zilio, C., Rossetto, L., Cavallini, A., “Foam height effects on heat transfer performance of 20 ppi aluminum foams”, Applied Thermal Engineering, 49, 55-60, (2012).
• [32] Noh, J.-S., Lee, K. B., Lee, C. G., “Pressure loss and forced convective heat transfer in an annulus filled with aluminum foam”, International Communications in Heat and Mass Transfer, 33(4), 434-444, (2006).
• [33] Salas, K. I., Waas, A. M., “Convective Heat Transfer in Open Cell Metal Foams”, Journal of Heat Transfer, 129(9), 1217, (2007).
• [34] Sertkaya, A. A., Ateş, A., Altınısık, K., “Designing of Open Cell Aluminum Foam Heat Exchanger and Modelling of its Thermal Performance by Using Ann Method”, Journal of Polytechnic, 19 (1): 31-37, (2016).