Natural Convection in Triangular Cavity Filled with Nanofluid: Lattice Boltzmann Simulation

doi:10.19596/j.cnki.1001-246x.8170

Abstract

Abstract: Lattice Boltzmann method was used to study natural convection in an isosceles right-angled triangular cavity filled with water-alumina nanofluids. Effects of Rayleigh number, particle volume fraction, heat source location and other factors on convective heat transfer are discussed, as well as effects of nanofluid models on simulation results. It shows that at low Rayleigh numbers, as the heat source moves upward on the left wall, the heat transfer efficiency gradually increases. At high Rayleigh number (Ra=10⁶), the opposite phenomenon was observed. In a single-phase nanofluid model, simulation results show that the average Nusselt number ratio of the hot wall surface increases approximately linearly with the increase of volume fraction. An improved nanofluid model results show that the average Nusselt number ratio increases with the increase of volume fraction, but the slope of the average Nusselt number ratio decreases gradually. The heat transfer efficiency simulated with the improved model is higher than that of the single-phase model. This is because the improved model considers force between particles and heat transfer, which exists in actual situation.

Key words: lattice Boltzmann method, triangular cavity, nanofluid, natural convection

CLC Number:

TK124

YUAN Junjie, YE Xin, SHAN Yanguang. Natural Convection in Triangular Cavity Filled with Nanofluid: Lattice Boltzmann Simulation[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2021, 38(1): 57-68.

References

[1] FLACK R D, KONOPNICKI T T, ROOKE J H. The measurement of natural convective heat transfer in triangular enclosures[J]. Journal of Neuroscience the Official Journal of the Society for Neuroscience, 1979, 101(4):648.
[2] OZTOP H F, VAROL Y, KOCA A. Experimental and numerical analysis of buoyancy-induced flow in inclined triangular enclosures[J]. International Communications in Heat and Mass Transfer, 2012, 39(8):1237-1244.
[3] RAJ R, PRADYUMNA K C, RAKSHITH B R. Combined natural convection and surface radiation inside vented triangular enclosure:An experimental study[J]. MATEC Web of Conferences, 2018, 144(6):04019.
[4] WANG T T, GAO Q, CHEN J, et al. Lattice Boltzmann simulation of mixed convection in an enclosure filled with porous medium[J]. Chinese J Comput Phys, 2017, 34(1):39-46.
[5] SUN J C, DU P, LI P S, et al. Natural convection heat transfer in a porous medium with partially thermally active walls:Lattice Boltzmann method[J]. Chinese J Comput Phys, 2017, 34(5):583-592.
[6] WANG J, LOU Q, XU H T, et al. Lattice Boltzmann simulation of double-diffusion natural convection in a enclosure with Soret and Dufour effects[J]. Chinese J Comput Phys, 2018, 35(4):405-412.
[7] DUAN Y L, LIU R X. Lattice Boltzmann simulation of triangular cavity flow and free-surface problems[J]. Journal of Hydrodynamics, 2007, 19(2):127-134.
[8] AN B, BERGADA J M, MELLIBOVSKY F. The lid-driven right-angled isosceles triangular cavity flow[J]. Journal of Fluid Mechanics, 2019, 875:476-519.
[9] MEJRI I, MAHMOUDI A, ABBASSI M A. LBM simulation of natural convection in an inclined triangular cavity filled with water[J]. Alexandria Engineering Journal, 2016:S1110016816300333.
[10] TAHER M A,KIM H D,LEE Y W. LBM simulation of friction factor and heat transfer on the moving lid of a triangular cavity[J]. Heat Transfer Research, 2017, 48(11):1025-1045.
[11] GHASEMI B, AMINOSSADATI S M. Mixed convection in a lid-driven triangular enclosure filled with nanofluids[J]. International Communications in Heat and Mass Transfer, 2010, 37(8):1142-1148.
[12] YU Z T, XU X, HU Y C. Numerical study of transient buoyancy-driven convective heat transfer of water-based nanofluids in a bottom-heated isosceles triangular enclosure[J]. International Journal of Heat and Mass Transfer, 2011, 54(1/2/3):526-532.
[13] SUN Q, POP I. Free convection in a tilted triangle porous cavity filled with Cu-water nanofluid with flush mounted heater on the wall[J]. International Journal of Numerical Methods for Heat and Fluid Flow, 2013, 24(1):2-20.
[14] JAVED T,MEHMOOD Z, SIDDIQUI M A. Mixed convection in a triangular cavity permeated with micropolar nanofluid-saturated porous medium under the impact of MHD[J]. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2017, 39:3897-3909.
[15] KOLSI L, OZTOP H F. Control of heat transfer and fluid flow via a moving fin in a triangular enclosures filled with nanofluid[J]. Heat Transfer Research, 2019, 50(2):159-181.
[16] RASHAD A M, CHAMKHA A J, ISMAEL M A, et al. Magnetohydrodynamics natural convection in a triangular cavity filled with a Cu-Al₂O₃/water hybrid nanofluid with localized heating from below and internal heat generation[J]. Journal of Heat Transfer, 2018, 140(7):072502.1-072502.13.
[17] GHASEMI B, AMINOSSADATI S M. Brownian motion of nanoparticles in a triangular enclosure with natural convection[J]. International Journal of Thermal Sciences, 2010, 49(6):931-940.
[18] 宣益民, 李强, 姚正平. 纳米流体的格子Boltzmann模拟[J]. 中国科学E:技术科学, 2004, 34(3):280-287.
[19] SHAN X, CHEN H. Lattice Boltzmann model for simulating flows with multiple phases and components[J]. Physical Review E, 1993, 47(3):1815-1819.
[20] 郭亚丽, 徐鹤函, 沈胜强. 利用格子Boltzmann方法模拟矩形腔内纳米流体Raleigh-Benard对流[J]. 物理学报, 2013, 62(14):318-323.
[21] 齐聪, 何玉荣, 闫盛楠. 矩形腔内纳米流体自然对流的两相格子Boltzmann模拟[J]. 工程热物理学报, 2014, 35(2):282-286.
[22] GUO Y L, QIN D Y, SHEN S Q. Simulation of nanofluid heat transfer enhancement characteristics with lattice Boltzmann method[J]. Journal of Dalian University of Technology, 2013, 53(1):36-41.
[23] OZTOP H F, ABU-NADA E.Numerical study of natural convection in partially heated rectangular enclosures filled with nanofluids[J]. International Journal of Heat and Fluid Flow, 2008, 29(5):1326-1336.
[24] 何雅玲, 王勇, 李庆. 格子Boltzmann方法的理论及应用[M]. 北京:科学出版社, 2009.