Numerical Analysis of Flow and Heat Transfer for Semi Spheres Placed As Multiple Serials In a Channel

Year 2018, , 76 - 82, 20.09.2018

Koray Karabulut , Doğan Engin Alnak , Ferhat Koca , Coşkun Özalp

https://doi.org/10.26701/ems.377446

Cited By: 2

Abstract

Excessive heating of electronic equipments may cause both decreasing thermal performance of system and undesirable consequences such as increased thermal stresses and mechanical defects in the system. In the literature, there are many studies including applications of thermal analysis and technologies in order to make cooling more effective. In this study, flow and heat transfer are investigated numerically in the case of three dimensional, incompressible, fully developed and laminar flow for semi spheres placed as multiple serials in a channel. The continuity, Navier-Stokes and energy equations are solved numerically by using  Ansys Fluent-17.0 software program. Air is taken as working fluid. Inlet temperature of the air and sphere surface temperatures are 300 K and 350 K, respectively. The effects of location of semi spheres as multiple serials, placement angle and positions of sphres according to each other on the pressure drop and heat transfer enhancement for case of different Re numbers (Re=100, 200, 400 ve 800) are researched. The obtained results show that the positions of spheres have a great importance in the case of placement as multiple serials of semi spheres.

Keywords

Semi sphere, converging and diverging channels, heat transfer

References

• Sparrow, E.M., Prata, A.T., (1983). Numerical solutions for laminar flow and heat transfer in a periodically converging-diverging tube, with experimental confirmation. Numerical Heat Transfer 6(4): 441–61, Doi: 10.1080/01495728308963099.
• Patankar, S.V., Liu, C.H., Sparrow, E.M. (1977). The periodic thermally developed in ducts with streamwise periodic wall temperature or heat flux. International Journal of Heat and Mass Transfer. 21(5): 557-566.
• Kelkar, K.M. and Patankar, S.V. (1987). Numerical prediction of flow and heat transfer in a parallel plate channel with staggered fins. Journal of Heat Transfer, 109(1): 25-30.
• Wang, G., Vanka, S.P., (1995). Convective heat transfer in periodic wavy passages. International Journal of Heat and Mass Transfer 38(17): 3219–30, Doi: 10.1016/0017-9310(95)00051-A.
• Min, C., Qi, C., Kong, X., Dong, J., (2010). Experimental study of rectangular channel with modified rectangular longitudinal vortex generators. International Journal of Heat and Mass Transfer 53(15–16): 3023–9, Doi: 10.1016/j.ijheatmasstransfer.2010.03.026.
• Pankaj, S., Gautm, B., Subrata, S. (2014). Comparision of winglet-type vortex generators periodically deployed in a plate-fin heat exchanger-a synergy based analysis. International Journal of Heat and Mass Transfer, 74: 292-305.
• Zhu, J.X., Fiebig, M., Mitra, N.K., (1995). Numerical investigation of turbulent flows and heat transfer in a rib-roughened channel with longitudinal vortex generators. International Journal of Heat and Mass Transfer 38(3): 495–501, Doi: 10.1016/0017-9310(94)00177-W.
• Chunhua, M., Chengying, Q., Enyu, W., Liting, T., Yaju, Q. (2012). Numerical ınvestigation of turbulent flow and heat transfer in a channel with novel longitudinal vortex generators. International Journal of Heat and Mass Transfer, 55(23-24): 7268-7277.
• Sohankar, A. (2007). Heat transfer augmentation in a rectangular channel with vee-shaped vortex generator. International Journal of Heat and Fluid Flow. vol. 28, no. 2, p. 306-317.
• Patankar, S.V. and Prakash, C. (1981). Analysis of the effect of plate thickness on laminar flow and heat transfer in ınterrupted plate passages. International Journal of Heat and Mass Transfer, 24(11): 1801-1810.
• Yılmaz, T. (1982). Numerical solutions of navier-stokes equations for laminar flow in rows of plates in staggered arrangement. International Journal of Heat and Fluid Flow, 3(4): 201-206.
• Yılmaz, T. and Ayhan, T. (1983). Birbirleriyle bağlantılı daralan ve genişleyen kanallarda ısı transferi. 4. Ulusal Isı Bilimi ve Tekniği Kongresi, 133-149.
• Fuji, M., Sensimo, Y., Yamanaka, G. (1988). Heat transfer and pressure drop of perforated surface heat excganger with pasage enlargement and contraction. International Journal of Heat and Mass Transfer. 31(1): 135-142.
• Kotcioğlu, I., Bölükbaşı, A. (2003). Düşey dikdörtgen kesitli bir kanalda farklı kanatçıklı yüzeylerde ısı transferinin incelenmesi. Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi. 5(2): 89-102.
• Erdinc, M.T. (2014). Birbirleriyle bağlantılı daralan ve genişleyen kanallarda akış ve ısı geçişinin sayısal olarak incelenmesi. Osmaniye Korkut Ata Üniversitesi Fen Bilimleri Enstitüsü. Yüksek Lisans Tezi. p. 100.