Buoyancy-driven flow of nanofluids in a cavity considering the Ludwig–Soret effect and sedimentation: Numerical study and experimental validation

摘要: Abstract Results of numerical simulation and experiments carried out to study natural convection heat transfer Al2O3/water nanofluids (volume concentrations 1%, 2%, 3%, 4%) in a rectangular cavity are presented. The top wall the enclosure is kept at higher temperature than bottom wall, while other sidewalls thermally insulated. aims elucidate influence microscopic phenomena, including Ludwig–Soret effect (also known as thermophoresis), Brownian motion sedimentation nanoparticles, on with nanofluids. Four different models examined analysis considering absence or presence either sedimentation, effect. In addition, an experimental investigation performed size 25 mm width height, 60 mm length validate results obtained from study. comparisons between data unfold that when effect, nanoparticles considered model, predicted Nusselt number very close data. However, difference increased volume concentration becomes 2%.