Thermophoresis of charged spheroids has been widely applied in biology and medical science. In this work, we report an analysis of the anisotropic thermophoresis of diluted spheroidal colloids in aqueous media for extremely thin EDL cases. Under the boundary layer approximation, we formulate the thermophoretic velocity, the thermophoretic force, and the thermodiffusion coefficient of a randomly dispersed spheroid. The parametric studies show that under the aforementioned conditions, the thermophoresis is anisotropic and its thermodiffusion coefficient should be considered as a vector, D_T. The thermodiffusion coefficient values and directions of D_T are strongly related to the aspect ratio and the angle θ between the externally applied temperature gradient and the particle's axis of revolution: The increasing aspect ratio enlarges the thermodiffusion coefficient value D_T of prolate (oblate) spheroids to a constant value when θ < 60° (θ > 45°), and it reduces D_T of prolate (oblate) spheroids to a constant value when θ > 60° (θ < 45°). The thermodiffusion coefficient direction of both prolate and oblate spheroids deviates slightly from −∇T_∞ for a small aspect ratio, and such deviation becomes serious for a large aspect ratio.

中文翻译：

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带电球状胶体在水介质中的各向异性热泳分析分析，用于极薄 EDL 情况

带电球体的热泳已广泛应用于生物学和医学领域。在这项工作中，我们报告了对极薄 EDL 情况下水性介质中稀释球状胶体的各向异性热泳的分析。在边界层近似下，我们制定了随机分散球体的热泳速度、热泳力和热扩散系数。参数研究表明，在上述条件下，热泳是各向异性的，其热扩散系数应视为向量，D _T。D _T的热扩散系数值和方向与纵横比和角度θ密切相关在外部施加的温度梯度和粒子旋转轴之间：当θ  < 60° ( θ  > 45°) 时，增加的纵横比使扁长（扁圆）球体的热扩散系数值D _T增大到恒定值，并减小了D当θ  > 60° ( θ  < 45°)时，扁长（扁圆）球体的_T为恒定值。扁长球体和扁球体的热扩散系数方向对于小纵横比都略有偏离-∇ T _∞，而对于大纵横比，这种偏离变得严重。