The effect of various conductivity and viscosity models considering Brownian motion on nanofluids mixed convection flow and heat transfer

Document Type : Original Research Paper

Authors

Department of Mechanical Engineering, Mechanical Engineering University of Kashan, Kashan, I. R. Iran

Abstract

 In this paper the effect of using various models for conductivity and viscosity considering Brownian motion of nanoparticles is investigated. This study is numerically conducted inside a cavity full of Water-Al2O3 nanofluid at the case of mixed convection heat transfer. The effect of some parameters such as the nanoparticle volume fraction, Rayleigh, Richardson and Reynolds numbers has been examined. The governing equations with specified boundary conditions has been solved using finite volume method. A computer code has been prepared for this purpose. The results are presented in form of stream functions, isotherms, Nusselt number and the flow power with and without the Brownian motion taken into consideration. The results show that for all the applied models the stream functions and isotherm have approximately same patterns and no considerable difference has been observed. In all the studied models when considering the Brownian motion, the average Nusselt number is higher than not taking this effect into account. The models of Koo-Kleinstreuer and Li-Kleinstreuer give almost same values for the maximum stream function and average Nusselt number. It is also true about the models of Vajjha-Das and Xiao et al. 

Keywords

References

[1]  M.A. Mansour, R.A. Mohamed, M.M. Abd-Elaziz, S.E. Ahmed: Numerical simulation of mixed convection flows in a square lid-driven cavity partially heated from below using nanofluid, International Communications in Heat and Mass Transfer 37 (2010) 1504–1512.
[2]  B. Ghasemi, S.M. Aminossadati: Mixed convection in a lid-driven triangular enclosure filled with nanofluids, International Communications in Heat and Mass Transfer 37 (2010) 1142–1148.
[3]  G.A. Sheikhzadeh, M. Ebrahim Qomi, N. Hajialigol, A. Fattahi: Numerical study of mixed convection flows in a lid-driven enclosure filled With nanofluid using variable properties, International Results in Physics 2 (2012) 5-13.
[4]  I. Pishkar, B. Ghasemi: Cooling enhancement of two fins in a horizontal channel by nanofluid mixed convection, International Journal of Thermal Sciences 59 (2012) 141-151.
[5]  A.J. Chamkhaa, E. Abu-Nada: Mixed convection flow in single- and double-lid driven square cavities filled with water–Al2O3 nanofluid: Effect of viscosity models, European Journal of Mechanics B/Fluids 36 (2012) 82-96.
[6]  A.A. Abbasian Arani, S. Mazrouei Sebdani, M. Mahmoodi, A. Ardeshiri, M. Aliakbari: Numerical study of mixed convection flow in a lid-driven cavity with sinusoidal heating on side walls using nanofluid, Super lattices and Micro structures 51 (2012) 893-911.
[7]  B. Ghasemi, S.M. Aminossadati: Brownian motion of nanoparticles in a triangular enclosure with natural convection, International Journal of Thermal Sciences 49 (2010) 931–940.
[8]  H.A. Pakravan, M. Yaghoubi: Combined thermophoresis, Brownian motion and Dufour effec ts on natural convection of nano fluids, International Journal of Thermal Sciences 50 (2011) 394 – 402.
[9]  X. Wang, D. Li, H. Jiao: Heat Transfer Enhancement of CuO-water Nanouids Considering Brownian Motion of Nanoparticles in a Singular Cavity, Journal of Information & Computational Science 9 (2012) 1223-1235.
[10] Z. Haddad, E. Abu-Nada, H.F. Oztop, A. Mataoui: Natural convection in nanofluids: Are the thermophoresis and Brownian motion effects significant in nano fluid heat transfer enhancement?, International Journal of Thermal Sciences 57 (2012) 152 -162.
[11] H.R. Seyf, B. Nikaaein: Analysis of Brownian motion and particle size effects on the thermal behavior and cooling performance of microchannel heat sinks, International Journal of Thermal Sciences 58 (2012) 36-44.
[12] A.A. Abbasian Arani, A. Aghaei, H. Ehteram: Numerical investigation of Brownian motion effect on nanofluid mixed convection in enclosure with a hot central heat source, Journal of Modeling in Engineering  Semnan University (2013).
[13] E. Abu-Nada, Z. Masoud, A. Hijazi: Natural convection heat transfer enhancement in horizontal concentric annuli using nanofluids, International Communications in Heat and Mass Transfer 35(2008) 657 – 665.
[14] A. Bijan: Convection heat transfer, Willey, NewYork, Third edition (1984).
[15] K. Khanafer, K. Vafai: A critical synthesis of thermo physical characteristics of nanofluids, International Journal of Heat and Mass Transfer 54 (2011) 4410-4428.
[16] H.C. Brinkman: The viscosity of concentrated suspensions and solution, The Journal of Chemical Physics 20 (1952) 571–581.
[17] J. Maxwell: A Treatise on Electricity and Magnetism, second ed., Oxford University Press, Cambridge, UK (1904).
[18] J. Koo, C. Kleinstreuer: A new thermal conductivity model for nanofluids, Journal of Nanoparticle Research 6 (2004) 577–588.
[19] R.S. Vajjha, D.K. Das: Experimental determination of thermal conductivity of three nanofluids and development of new correlations, International Journal of Heat and Mass Transfer 52 (2009) 4675–4682.
[20] J. Li, C. Kleinstreuer: Thermal performance of nanofluid flow in microchannels, International Journal of Heat and Fluid Flow 29 (2008) 1221–1232.
[21] B. Xiao, Y. Yang, L. Chen: Developing a novel form of thermal conductivity of nanofluids with Brownian motion effect by means of fractal geometry, Powder Technology 23 (2013) 409–414.
[22] M. Hemmat Esfe, S. Saedodin, O. Mahian, S, Wongwises: Thermal conductivity of Al2O3/water nanofluids, Journal of Thermal Analysis and Calorimetry 117(2014) 675–681.
Challenges in Nano and Micro Scale Science and Technology
Volume 4, Issue 1 - Serial Number 1
January 2016
Pages 19-28

Files

Share

How to cite

Statistics