Heat transfer enhancement using temperature-dependent effective properties of alumina-water nanoliquid with thermo-solutal Marangoni convection: A sensitivity analysis

Abstract

The sensitivity of the heat transport rate in the thermo-solutal Marangoni convection of $${\mathrm{Al}}_{2}{\mathrm{O}}_{3}-{\mathrm{H}}_{2}\mathrm{O}$$ nanoliquid at 300 K is analyzed. The nanoliquid is modeled using the modified Buongiorno model which incorporates the Brownian motion, effective nanoliquid properties, and thermophoresis effects. The thermophysical models proposed by Khanafer and Vafai are chosen in this analysis as these correlations are in good agreement with the experimental values. External constraining factors like thermal radiation and variable magnetic field are also considered. The basic equations are solved using apposite transformation variables and Finite Difference Method (FDM). The impacts of the effectual parameters on all the profiles are analyzed. Furthermore, the heat transport is analyzed by executing a Response Surface Methodology (RSM) model with the Brownian motion parameter ( $$0.1\le \mathrm{Nb}\le 0.5$$ ), thermophoretic parameter ( $$0.1\le \mathrm{Nt}\le 0.5$$ ), and nanoparticle volume fraction ( $$1\%\le \varphi \le 3\%$$ ). The modified Buongiorno model yields lower temperature and concentration profiles when compared to the conventional Buongiorno model. The heat transfer rate is the most sensitive to the Brownian motion parameter than thermophoresis and nanoparticle (NP) volume fraction parameters. The results of this study would be instrumental in improving the efficiency of the welding process, crystal growth, and coating technologies.