This paper focusses on a theoretical analysis of the entropic generation and heat-transfer characteristics of electromagnetohydrodynamic (EMHD) flow in vertical hydrophobic microchannels. The flow viscosity, electrical conductivity, and thermal conductivity are assumed to be temperature variant. The fluid velocity and energy transfer equations associated with a system of coupled non-linear equations dealing with hydrophobic slip conditions are solved using a finite volume method associated with lubrication theory. The Debye–Hckel approximation is employed in an electrical double layer combined with the Poisson–Boltzmann equation to acquire an analytical solution for the electrical potential function. Slip velocities along with constant temperatures are provided to obtain numerical solutions for the case of a fully developed EMHD flow, in order to reveal the influence of fluid rheology. The results are presented for electromagnetic transport with variable viscosity over hydrophobic interfaces. Numerical and analytical validations are performed using the existing experimental results. In this study, we vizualize the significance of variable viscosity, electrical conductivity, and thermal conductivity on temperature distributions in the presence of a magnetic field. In this work, entropy generation is represented in terms of the Bejan number, which greatly impacts the normalized electroosmotic flow as well as the thermophysical parameters, leading to a minimization of the entropy-generation rate.

本文着重对垂直疏水微通道中电磁流体动力学（EMHD）流的熵产生和传热特性进行理论分析。流动粘度，电导率和热导率假定为温度变化。使用与润滑理论相关的有限体积方法，可以解决与处理疏水滑移条件的耦合非线性方程组相关联的流体速度和能量传递方程。在电气双层中使用Debye-Hckel近似与Poisson-Boltzmann方程相结合，以获得电势函数的解析解。提供了滑动速度和恒定温度，以针对完全发展的EMHD流量获得数值解，为了揭示流体流变学的影响。给出了在疏水界面上具有可变粘度的电磁传输的结果。使用现有的实验结果进行数值和分析验证。在这项研究中，我们生动地说明了在存在磁场的情况下，可变粘度，电导率和热导率对温度分布的重要性。在这项工作中，用贝詹数表示熵的产生，这极大地影响了标准化的电渗流以及热物理参数，从而使熵的产生速率最小化。使用现有的实验结果进行数值和分析验证。在这项研究中，我们生动地说明了在存在磁场的情况下，可变粘度，电导率和热导率对温度分布的重要性。在这项工作中，用贝詹数表示熵的产生，这极大地影响了标准化的电渗流以及热物理参数，从而使熵的产生速率最小化。使用现有的实验结果进行数值和分析验证。在这项研究中，我们生动地说明了在存在磁场的情况下，可变粘度，电导率和热导率对温度分布的重要性。在这项工作中，用贝詹数表示熵的产生，这极大地影响了标准化的电渗流以及热物理参数，从而使熵的产生速率最小化。