The theoretical investigation of thermal convection in a horizontal layer of micropolar nanofluid is examined within the rule of linear stability hypothesis. The model applied for nanofluid integrates the impact of Brownian and thermophoresis diffusions. The flux of the volumetric fraction of nanoparticles is considered to be nil on the boundaries. The critical eigenvalues are achieved using the Galerkin approach, and the results are discussed and illustrated graphically. The results show that the Lewis number, the modified diffusivity ratio, the nanoparticle Rayleigh number, and the coefficient of coupling amid spin and heat flux accelerate the onset of convective motion, whereas the micropolar parameter and the coefficient of coupling amid vorticity and spin delay the onset of convective motion in the system.

中文翻译：

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一层微极纳米流体中的热对流

在线性稳定性假设的规则内检查了微极性纳米流体水平层中热对流的理论研究。应用于纳米流体的模型整合了布朗和热泳扩散的影响。纳米粒子的体积分数的通量在边界上被认为是零。使用 Galerkin 方法获得临界特征值，并以图形方式讨论和说明结果。结果表明，路易斯数、修正扩散率比、纳米粒子瑞利数以及自旋和热通量耦合系数加速了对流运动的开始，而微极参数和涡旋和自旋耦合系数延迟了对流运动的发生。系统中对流运动的开始。