Experimental and Numerical Investigation of Heat Transfer in Different Winglet- Surface in a Vertical Rectangular Duct

Abstract

This paper presents the experimental and numerical results of forced convection in a rectangular vertical channel. Experiments have been performed for three different fin shapes including, flat plate, cylindrical and diffuse (Narrow wide) (with the angle of θ = 60°) inside the wind channel. The obtained results are presented to show changes in Nusselt numbers and friction factor for all tested winglet types. Furthermore for each type of winglets, test results have been compared between winglets in the term of temperature distribution along the winglets. It has been concluded that, heat transfer coefficient can be improved due to from renewal as periodic of the boundary layer with effect, which of this winglets have particularly placed in the event of groups periodically contracting and expanding in the winglets. Basic conservation equations are solved in continuous flow regime using three-dimensional simulation in the turbulent flow conditions by means of ANSYS Fluent as a CFD program based on finite volume method.

Keywords

• heat transfer,heat exchanger,winglet,numerical simulation,ansys,fluent

References

1. [1] Ahmed HE, Ahmed MI. Thermal performance of annulus with its applications: A review. Renewable and Sustainable Energy Reviews (2016).
2. [2] Deb P, Biswas G, Mitra NK. Heat transfer and flow structure in laminar and turbulent flows in a rectangular channel with longitudinal vortices. International Journal of Heat and Mass Transfer (1995) 38(13):2427–2444.
3. [3] Floryan JM, Novak M. Free convection heat transfer in multiple vertical channels. International Journal of Heat and Fluid Flow (1995) 16(4):244–253.
4. [4] Kotcioglu I, Bölükbaşı A. Experimental Investigation Heat Transfer In Different Winglet-Surfaces In A Verttical Rectangular Duct. DEÜ Mühendislik Fakültesi Fen ve Mühendislik Dergisi (2003) 5(2):89–102.
5. [5] Kotcioglu I, Cansiz A, Khalaji MN. Experimental investigation for optimization of design parameters in a rectangular duct with plate-fins heat exchanger by Taguchi method. Applied Thermal Engineering (2013) 50(1):604–613.
6. [6] Briggs DC, London AL. The heat transfer and flow friction characteristics of five offset rectangular and six plain triangular plate-fin heat transfer surfaces. Stanford, Calif.: Stanford University. Dept. of Mechanical Engineering (1960). viii, 74.
7. [7] Kotcioglu I, Ayhan T, Olgun H, Ayhan B. Heat transfer and flow structure in a rectangular channel with wing-type vortex generator. Turkish Journal of Engineering and Environmental Sciences (1998) 22(3):185–196.
8. [8] Maughan JR, Incropera FP. Use of Vortex Generators and Ribs for Heat Transfer Enhancement at the Top Surface of a Uniformly Heated Horizontal Channel With Mixed Convection Flow. Journal of Heat Transfer (1991) 113(2):504. doi:10.1115/1.2910592.

9. [9] Masao F, Yu S, Goro Y. Heat transfer and pressure drop of perforated surface heat exchanger with passage enlargement and contraction. International Journal of Heat and Mass Transfer (1988) 31(1):135–142. doi:10.1016/0017-9310(88)90230-X.
10. [10] Caliskan S, Nasiri Khalaji M, Baskaya S, Kotcioglu I. Design Analysis of Impinging Jet Array Heat Trans-fer From a Surface With V-Shaped and Convergent–Divergent Ribs by the Taguchi Method. Heat Transfer Engineering (2016) 37(15):1252–1266.
11. [11] Sparrow EM. Periodically Conwerging-Diverging Tubes and Their Turbulent Heat Transfer Pressure Drop, Fluid Flow, and Enhancement Characteristics. Journal of Heat Transfer (1984) 106(1):55-63.
12. [12] Garg VK, Maji PK. Laminar flow and heat transfer in a periodically converging‐diverging channel. International Journal for Numerical Methods in Fluids (1988) 8(5):579–597.
13. [13] Balasundar P, Sastri VM. Natural convection heat transfer in overlapping discrete plate arrays. International Journal of Heat and Mass Transfer (1994) 37:107–111.
14. [14] Sahin HM, Dal AR, Baysal E. 3-D Numerical study on the correlation between variable inclined fin angles and thermal behavior in plate fin-tube heat exchanger. Applied Thermal Engineering (2007) 27(11):1806–1816.
15. [15] Ozceyhan V, Gunes S, Buyukalaca O, Altuntop N. Heat transfer enhancement in a tube using circular cross sectional rings separated from wall. Applied Energy (2008) 85(10):988–1001. doi:10.1016/j.apenergy.2008.02.007.
16. [16] Hsieh S-S, Liu M-H, Wu F-Y. Developing turbulent mixed convection in a horizontal circular tube with strip-type inserts. International Journal of Heat and Mass Transfer (1998) 41(8-9):1049–1063. doi:10.1016/S0017-9310(97)00181-6.
17. [17] Promvonge P. Thermal augmentation in circular tube with twisted tape and wire coil turbulators. Energy Conversion and Management (2008) 49(11):2949–2955. doi:10.1016/j.enconman.2008.06.022.
18. [18] Eiamsa-ard S, Promvonge P. Experimental in-vestigation of heat transfer and friction characteristics in a circular tube fitted with V-nozzle turbulators. International Communications in Heat and Mass Transfer (2006) 33(5):591–600.
19. [19] Eiamsa-ard S, Promvonge P. Enhancement of heat transfer in a tube with regularly-spaced helical tape swirl generators. Solar Energy (2005) 78(4):483–494. doi:10.1016/j.solener.2004.09.021.
20. [20] Yakut K, Sahin B. The effects of vortex characteristics on performance of coiled wire turbulators used for heat transfer augmentation. Applied Thermal Engineering (2004) 24(16):2427–2438.