Numerical analysis of the free convection heat transfer in an H-shaped cavity loaded with alumina–water nanofluid is performed in this work. The entire bottom wall of the H-shaped enclosure and the top rib are at the hot temperature, the two sidewalls are at the lower temperature, and the others are insulated. This study aims to elucidate the influences of different variables on the heat transfer of nanofluid, namely the Rayleigh number (Ra = 10⁴–10⁶), nanoparticle volume fraction percentage (ϕ = 0–2%), aspect ratio (AR = 0.2–0.4), installation of baffle, location of baffle in the cavity, and the types of baffle boundary condition. To model the buoyancy force, the Boussinesq approximation is employed. The characteristics of flow and thermal transmission are presented in streamlines and isotherms. The results show that the heat transmission is improved by Rayleigh number enhancement and nanoparticle volume fraction due to the enhanced temperature gradient and the nanofluid thermal characteristics. In addition, the baffle installation at the bottom rib under a non-adiabatic boundary condition improve the heat transfer because the bottom wall has a larger mean temperature than the top wall.

在这项工作中，对装有氧化铝-水纳米流体的H形腔中的自由对流换热进行了数值分析。H形外壳的整个底壁和顶肋处于高温状态，两个侧壁处于较低温度，而其他处于绝缘状态。这项研究旨在阐明不同变量对纳米流体传热的影响，即瑞利数（Ra = 10 ⁴ –10 ⁶），纳米颗粒的体积分数百分比（ϕ = 0–2％），纵横比（AR = 0.2–0.4），挡板的安装，挡板在腔中的位置以及挡板边界条件的类型。为了对浮力建模，采用了Boussinesq逼近法。流动和热传递的特性以流线和等温线表示。结果表明，由于提高了温度梯度和纳米流体的热特性，通过瑞利数增加和纳米颗粒体积分数改善了热传递。另外，在非绝热边界条件下将隔板安装在底部肋骨上，因为底壁的平均温度比顶壁的平均温度高，所以改善了热传递。