Mixed convection study in a ventilated square cavity using nanofluids

Document Type : Full Lenght Research Article


1 Federal University of Itajubá, Itabira, Brazil

2 Federal University of Itajubá - Itabira Campus

3 Federal University of Itajubá, Itajubá, Brazil


This work indicates a numerical study on the laminar heat transfer mixed convection in a square cavity with two openings (an inlet and an outlet) on vertical walls through which nanofluid flows. Two flow directions are examined: i) ascending flow which enters the bottom opening and exits the upper opening; ii) descending flow which enters the upper opening and exits the bottom opening. The ascending flow contributes to buoyancy forces while for the descending flow, the opposite takes place. The intention is to cool a heat source placed at the center of the geometry. The nanofluid has Copper nanoparticles and water as its base-fluid. The velocity and temperature of the entrance flow are known. Some results are experimentally and numerically validated. A mesh independency study is carried out. Some parameters are ranged as follows: i) the Reynolds number from 50 to 500, the nanofluid volume fraction from 0 to 1%, the Grashof number from 103 to 105. It is noteworthy to mention that in some cases, the fluid is stuck inside the cavity which weakens the heat transfer. The nanoparticles increase the heat transfer of 4% for the ascending primary flow inside the cavity.


Main Subjects

[1]    H. Moumni, H. Welhezi, E. Sediki, Numerical Investigation of Heat Transfer Enhancement in a Square Ventilated Cavity with Discrete Heat Sources Using Nanofluid, Heat and Mass Transfer and Physical Gasdynamics, 55 (3), 426-433, (2017).
[2]   F. F. Hinojosa, N. A. Rodriguez, J. Xamán, Heat transfer and airflow study of turbulent mixed convection in a ventilated cavity, Journal of Building Physics, 204-234, (2015).
[3]   E. Arquis, M. A. Rady, A. S. Nada, A numerical investigation and parametric study of cooling an array of multiple protruding heat sources by a laminar slot air jet, International Journal of Heat and Fluid Flow, 28, 787–800, (2007).
[4]   G. M. Rao and G. S. V. L. Narasimham, Laminar conjugate mixed convection in a vertical channel with heat generating components, International Journal of Heat and Mass Transfer, 50, 3561–3574, (2007).
[5]   M. Shahi, A. H. Mahmoudi, F. Talebi, Numerical study of mixed convective cooling in a square cavity ventilated and partially heated from the below utilizing nanofluid, International Communications in Heat and Mass Transfer, 37, 201-213,  (2010).
[6]    T. H. Nassan, S. Z. Heris, S. H. Noie, A comparison of experimental heat transfer characteristics for Al2O3/water and CuO/water nanofluids in square cross-section duct, International Communications of Heat and Mass Transfer, 37, 924-928, (2010).
[7]   M. Rostamani, S. F. Hosseinizadeh, M. Gorji, J. M. Khodadadi, Numerical study of turbulent forced convection flow of nanofluids in a long horizontal duct considering variable properties, International Communications in Heat and Mass Transfer, 37(10), 1426-1431, (2010).
[8]    R. Lotfi , Y. Saboohi, and A.M. Rashidi, Numerical study of forced convective heat transfer of Nanofluids: Comparison of different approaches, International Communications in Heat and Mass Transfer, 37, 74–78, (2010).
[9]   J. Jung, H. Oh, H. Kwak, Forced convective heat transfer of nanofluids in microchannels, International Journal of Heat and Mass Transfer 52 (2009) 466-472.
[10] A. Arefmanesh and M. Mostafa, Effects of uncertainties of viscosity models for Al2O3-water nanofluid on mixed convection numerical simulations, International Journal of Thermal Sciences, 50, 1706-1719, (2011).
[11] T. Behzardi, K. M. Shirvan, S. Mirzakhanlari, A. A. Sheikhrobat, Procedia Engineering, 127, 221-228, (2015).
[12] H. C. Brinkman, The viscosity of concentrated suspensions and solution, Journal of Chemical Physics, 20, 571-581, (1952).
[13] J. Maxwell, A treatise on electricity and magnetism, second ed., Oxford University Press, Cambridge, UK (1904).
[14] S. M. Aminossadati, B. Ghasemi, Natural convection cooling of a localized heat source at the bottom of a nanofluid-filled enclosure, European Journal of Mechanics B/Fluids, 28, 630-640, (2009).
[15] C. J. Ho, M. W. Chen, Z. W. Li, Numerical simulation of natural convection of nanofluid in a square enclosure: effects due to uncertainties of viscosity and thermal conductivity, International Journal of Heat and Mass Transfer, 51(17-18), 4506-4516 (2008).
[16] H. F. Oztop, E. Abu-Nada, Numerical study of natural convection in partially heated rectangular enclosures filled with nanofluids, International Journal of Heat and Fluid Flow, 29(5), 1326-1336, (2008).
[17] R. J. Krane, J. Jessee, Some detailed field measurements for a natural convection flow in a vertical square enclosure,   Proceedings of the First ASME-JSME Thermal Engineering Joint Conference, 1, 323-329, (1983).
[18] K. Khanafer, K. Vafai, M. Lightstone, Buoyancy-driven heat transfer enhancement in a two-dimensional enclosure utilizing nanofluids, International Journal of Heat and Mass Transfer, 46,  3639-3653, (2003).
[19] FIDAP Theoretical Manual, Fluid Dynamics International, Evanston, IL, USA (1990).
[20] G. Barakos, E. Mitsoulis, Natural convection flow in a square cavity revisited: laminar and turbulent models with wall functions, International Journal of Numerical Methods in Fluids, 18, 695-719, (1994).
 [21] De Val Davis, Natural convection of air in a square cavity, a benchmark numerical solution, International Journal of Numerical Methods in Fluids, 3,  249-264, (1962).
[22] T. Fusegi, J. M. Hyun, K. Kuwahara, B. Farouk, A numerical study of three-dimensional natural convection in a differentially heated cubical enclosure, International Journal of Heat and Mass Transfer, 34, 1543-1557, (1991).