Water aluminum oxide nanofluid benchmark model

Abstract The nanoparticles in fluid enhance the rate of heat transfer because of higher thermal conductivity of nanoparticles. In literature, researchers have used different numerical methods to simulate this phenomenon considering the fluid as a single phase or as a two phase system. In some cases, the numerical results were compared with experimental results and good agreements were achieved; while for other no comparison was done. On the other hand, there is no identical numerical research that compares various numerical approaches that can be used to study thermo-fluidic flow in nanofluid. Accordingly, in this study we have numerically solved a benchmark heat transfer nanofluid problem using three different widely used numerical approaches: Finite Element Method (FEM), Lattice Boltzmann Method (LBM) and Finite Difference Method (FDM). The numerical results were compared with experimental results in literature for validation purposes. Subsequently, a FEM simulation is carried out for a three dimensional domain to investigate the three dimensional effects of the enclosure’s walls on heat transfer in the nanofluid. The simulations were performed for water (H2O)-aluminum oxide(Al2O3) nanofluid at a particle concentration range of 1%–3% volume fraction. Numerical results in the forms of temperature, stream function and velocity variations as well as average Nusselt number at the walls have been presented for a range of Rayleigh numbers (for different particles concentration). While, a suitable combination of the governing control parameters resulted in an acceptable CFD outcomes for all three numerical methods, some differences have been observed between different numerical approaches which are reported in this study. Eventually, the strength and weakness of various numerical approaches are discussed in details.