Natural convection in a cavity with non-uniformly heated bottom wall, partly filled with a non-Newtonian nanofluid (Cu-water) layer and partly with air layer is studied numerically in this work. The mixture of water and copper nanoparticles shows a shear-thinning rheological behavior. The nanofluid's rheological parameters, i.e. consistency and flow index, are obtained according to the solid volume fraction, based on experimental data given in the literature. The general equations governing the physical problem are solved using the finite volume method over a wide range of Rayleigh number (10³ ≤ Ra₁ ≤ 10⁶), volume fraction of nanoparticles (0% ≤ ϕ ≤ 5%), filling level of the lower phase (0.25 H ≤ H_nf ≤ H) and the aspect ratio of the cavity (0.5 ≤ A ≤ 4.0). The results show that both flow intensity and heat transfer are enhanced when increasing these parameters. Predictive correlations relating the average Nusselt number to the quoted parameters have been proposed.

在这项工作中，对底壁加热不均匀，部分填充有非牛顿纳米流体（Cu-水）层，部分填充有空气层的空腔中的自然对流进行了数值研究。水和铜纳米颗粒的混合物显示出剪切稀化的流变行为。基于文献中给出的实验数据，根据固体体积分数获得了纳米流体的流变参数，即稠度和流动指数。管辖物理问题的一般方程是使用有限体积法在大范围的瑞利数求解（10 ³  ≤ 太阳神₁  ≤10 ⁶），纳米颗粒的体积分数（0％≤  φ  ≤5％），的填充水平下相（0.25  H ≤  ħ _NF  ≤  ħ）和所述腔（0.5≤的纵横比 阿 ≤4.0）。结果表明，当增加这些参数时，流动强度和传热都得到增强。已经提出了将平均努塞尔数与所引用参数相关的预测相关性。