INVESTIGATION OF COMBINED HEAT TRANSFER AND LAMINAR FLUID FLOW IN TWO AND THREE DIMENSIONAL DUCTS WITH AN OPEN CAVITY

Öz

In this study, developing combined forced and natural convection heat transfer and fluid flow in a duct with an open cavity are numerically studied using two- and three-dimensional models of various cavity size and flow induced parameters. The left wall of the cavity is isothermal while all other walls, including duct walls, are assumed to be adiabatic. Air (Pr=0.71) flows through the duct. The geometrical parameters used in this work are the cavity width to cavity height ratio (0.5≤W/D≤2), and the channel height to cavity height ratio (0.25≤H/D≤2). The flow induced parameters consists of the Reynolds number (Re) and the Richardson number (Ri). Re=10, 100, 200 and Ri=0.01, 0.1, 1 and 10 cases are considered in the study. The effects of the geometrical parameters of the cavity as well as the flow parameters on the fluid flow patterns and the temperature distribution (isotherms) were analyzed. The mean Nusselt number over the isothermal wall of the cavity was computed, and the effects of Richardson and Reynolds numbers, cavity aspect ratio and relative duct dimensions on the heat transfer were investigated. The results show that for all Re numbers, as the Richardson number increases, the air circulation becomes stronger inside the cavity. The flow inside the cavity for Ri>1 and Re>100 becomes three-dimensional. Based on the 2D and 3D numerical simulations, using the computed mean Nusselt numbers, correlations were developed

Anahtar Kelimeler

• Natural,Forced convection

Kaynakça

1. Abdellahoum C., Mataoui A. and Oztop H.F., 2015, Comparison of viscosity variation formulations for turbulent flow of Al2O3-water nanofluid over a heated cavity in a duct, Advanced Powder Technology, 26, 1210-1218.
2. Abdelmassih G., Vernet A. and Pallares J., 2016, Steady and unsteady mixed convection flow in a cubical open cavity with the bottom wall heated, International Journal of Heat and Mass Transfer, 101, 682-691.
3. Aminossadati S.M. and Ghasemi B., 2009, A numerical study of mixed convection in a horizontal channel with a discrete heat source in an open cavity, European Journal of Mechanics B-Fluid, 28, 590-598.
4. Aydin O., Unal A. and Ayhan T., 1999, Natural convection in rectangular enclosures heated from one side and cooled from the ceiling, International Journal of Heat and Mass Transfer, 42, 2345-2355.
5. Basak T., Roy S., Sharma P.K. and Pop I., 2009, Analysis of mixed convection flows within a square cavity with uniform and non-uniform heating of bottom wall, International Journal of Thermal Sciences, 48, 891-912.
6. Brown N.M. and Lai F.C., 2005, Correlations for combined heat and mass transfer from an open cavity in a horizontal channel, International Communications in Heat and Mass Transfer, 32, 1000-1008.
7. Burgos J., Cueta I. and Saluena, C., 2016, Numerical study of laminar mixed convection in a square open cavity, International Journal of Heat and Mass Transfer, 99, 599-612.
8. Calcagni B., Marsili F. and Paroncini M., 2005, Natural convective heat transfer in square enclosures heated from below, Applied Thermal Engineering, 25, 2522-2531.

9. Chang T.S. and Tsay Y.L., 2001, Natural convection heat transfer in an enclosure with a heated backward step, International Journal of Heat and Mass Transfer, 44, 3963-3971.
10. Das S.P., Chakraborty S. and Dutta P., 2002, Natural convection in a two-dimensional enclosure heated symmetrically from both sides, International Communications in Heat and Mass Transfer, 29, 345-354.
11. Erturk E., Corke T.C. and Gokcol C., 2005, Numerical solutions of 2-D steady incompressible driven cavity flow at high Reynolds numbers, International Journal for Numerical Methods in Fluids, 48, 747-774.
12. Fluent, FLUENT 6.3 User’s Guide, FLUENT Inc, Lebanon, NH, 2003.
13. Freitas C.J. and Street R.L., 1988, Non-Linear Transient Phenomena in a Complex Recirculating Flow - a Numerical Investigation, International Journal for Numerical Methods in Fluids, 8, 769-802.
14. Ishihara I., Fukui T. and Matsumoto R., 2002, Natural convection in a vertical rectangular enclosure with symmetrically localized heating and cooling zones, International Journal of Heat Fluid Flow, 23, 366-372.
15. Iwatsu R. and Hyun J.M., 1995, Three-dimensional Driven-Cavity Flows with a Vertical Temperature-Gradient, International Journal of Heat and Mass Transfer, 38, 3319-3328.
16. Khanafer K.M. and Chamkha A.J., 1999, Mixed convection flow in a lid-driven enclosure filled with a fluid-saturated porous medium, International Journal of Heat and Mass Transfer,42, 2465-2481.
17. Leong J.C., Brown N.M. and Lai F.C., 2005, Mixed convection from an open cavity in a horizontal channel, International Communications in Heat and Mass Transfer, 32, 583-592.
18. Manca O., Nardini S., Khanafer K. and Vafai K., 2003, Effect of heated wall position on mixed convection in a channel with an open cavity, Numerical Heat Transfer Part a-Applications, 43, 259-282.
19. Manca O., Nardini S. and Vafai K., 2006, Experimental investigation of mixed convection in a channel with an open cavity, Experimental Heat Transfer, 19, 53-68.
20. Manca O., Nardini S. and Vafai K., 2008, Experimental investigation of opposing mixed convection in a channel with an open cavity below, Experimental Heat Transfer, 21, 99-114.
21. Mehrez Z., Bouterra M., El Cafsi A. and Belghith A., 2013, Heat transfer and entropy generation analysis of nanofluids flow in an open cavity, Computers & Fluids, 88, 363-373.
22. Mehrez Z., El Cafsi A., Belghith A. and Le Quéré P., 2015,The entropy generation analysis in the mixed convective assisting flow of Cu–water nanofluid in an inclined open cavity, Advanced Powder Technology, 25, 1442-1451.
23. Moallemi M.K. and Jang K.S., 1992, Prandtl Number Effects on Laminar Mixed Convection Heat-Transfer in a Lid-Driven Cavity, International Journal of Heat and Mass Transfer, 35, 1881-1892.
24. Mohamad A.A. and Viskanta R., 1991, Transient Low Prandtl Number Fluid Convection in a Lid-Driven Cavity, Numerical Heat Transfer Part A-Applications, 19, 187-205.
25. Mohamad A.A. and Viskanta R., 1995, Flow and Heat-Transfer in a Lid-Driven Cavity Filled with a Stably Stratified Fluid, Applied Mathematical Modelling, 19, 465-472.
26. Muftuoglu A. and Bilgen E., 2008, Natural convection in an open square cavity with discrete heaters at their optimized positions, International Journal of Thermal Sciences, 47, 369-377.
27. Pallares J., Cuesta I., Grau F.X. and Giralt F., 1996, Natural convection in a cubical cavity heated from below at low Rayleigh numbers, International Journal of Heat and Mass Transfer, 39, 3233-3247.
28. Prasad A.K. and Koseff J.R., 1996, Combined forced and natural convection heat transfer in a deep lid driven cavity flow, International Journal of Heat and Fluid Flow, 17, 460-467.
29. Rahman M.M., Oztop H.F., Rahim N.A., Saidur R., Al-Salem K., Amin N., Mamun M.A.H. and Ahsan A., 2012, Computational analysis of mixed convection in a channel with a cavity heated from different sides, International Communications in Heat and Mass Transfer, 39, 78-84.
30. Selimefendigil F. and Yurddas A., 2012, Numerical Analysis of Mixed Convection Heat Transfer in Pulsating Flow for a Horizontal Channel with a Cavity Heated from Vertical Side and Below, Heat Transfer Research, 43, 509-525.
31. Sharif M.A.R., 2007, Laminar mixed convection in shallow inclined driven cavities with hot moving lid on top and cooled from bottom, Applied Thermal Engineering, 27, 1036-1042.
32. Sidik N.A.C., Jahanshaloo L. and Safdari A., 2014, The effect of mixed convection on particle laden flow analysis in a cavity using a Lattice Boltzmann method, Computers & Mathematics with Applications, 67, 52-61.
33. Stiriba Y., 2008, Analysis of the flow and heat transfer characteristics for assisting incompressible laminar flow past an open cavity, International Communications in Heat and Mass Transfer, 35, 901-907.
34. Stiriba Y., Ferre J.A. and Grau F.X., 2013, Heat transfer and fluid flow characteristics of laminar flow past an open cavity with heating from below, International Communications in Heat and Mass Transfer, 43, 8-15.
35. Stiriba Y., Grau F.X., Ferre J.A. and Vernet A., 2010, A numerical study of three-dimensional laminar mixed convection past an open cavity, International Journal of Heat and Mass Transfer, 53, 4797-4808.
36. Timuralp C., 2015, Investigation of the two and three dimensional heat transfer and fluid flow in a channel with an open cavity, Ph. D Thesis, Eskisehir Osmangazi University, Eskisehir, Turkey.