Simulation of copper_water nanofluid in a microchannel in slip flow regime using the lattice Boltzmann method with heat flux boundary condition

[摘要] Laminar forced convection heat transfer of water-Cu nanofluids in a microchannel is studied using the double population Thermal Lattice Boltzmann method (TLBM). The entering flow is at a lower temperature compared to the microchannel walls. The middle section of the microchannel is heated with a constant and uniform heat flux, simulated by means of the counter slip thermal energy boundary condition. Simulations are performed for nanoparticle volume fractions equal to 0.00%, 0.02% and 0.04% and slip coefficient equal to 0.001, 0.01 and 0.1. Reynolds number is equal to 1, 10 and 50.The model predictions are found to be in good agreement with earlier studies. Streamlines, isotherms, longitudinal variations of Nusselt number and slip velocity as well as velocity and temperature profiles for different cross sections are presented. The results indicate that LBM can be used to simulate forced convection for the nanofluid micro flows. They show that the microchannel performs better heat transfers at higher values of the Reynolds number. For all values of the Reynolds considered in this study, the average Nusselt number increases slightly as the solid volume fraction increases and the slip coefficient increases. The rate of this increase is more significant at higher values of the Reynolds number.

[发布机构] Dipartimento di Ingegneria Astronautica, Elettrica Ed Energetica, Sapienza Universitá di Roma, Via Eudossiana 18, Roma; 00184, Italy^1;Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Isfahan; 8196848531, Iran^2

[效力级别] 力学 [学科分类] 力学，机械学

[关键词] Energy boundary conditions;Flux boundary conditions;Laminar forced convections;Lattice Boltzmann method;Longitudinal variations;Nanoparticle volume fractions;Solid volume fraction;Thermal lattice-Boltzmann method