This paper accommodates numerical investigation on the onset of magneto-thermo-bioconvection in the nanofluid suspension of gyrotactic microbes saturated in a porous medium under the imposition of vertical throughflow and quadratic drag. The modified Darcy-Brinkman-Forchheimer model is utilized to drive the governing equations. The normal mode technique along with linear stability analysis is imposed to establish the eigenvlaue problem. An eight-order Galerkin methodology is utilized to numerically extract the critical thermal Rayleigh number values from the laborious eigenvalue problem. The power of vertical throughflow and quadratic drag is perceived to enhance the thermal energy transfer and stabilize the nanofluid suspension that consequently tries to restrict the convective process. The intensity of the magnetic field is identified to delay the onset of magneto-thermo-bioconvection. It is also found that the presence of fast-moving gyrotactic microorganisms and top-heavy nanofluid concentration forms an unstable system to accelerate the beginning of the magneto-thermo-bioconvection. The outcome of this work may find applications in microfluidic devices, enhanced oil recovery, and many other areas for controlling the speed of the convective process.

中文翻译：

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磁场和流量对含有回转微生物的Forchheimer扩展达西-布林克曼多孔纳米流体层热生物对流影响的数值研究

本文对饱和在多孔介质中的旋转微生物的纳米流体悬浮液中在垂直通流和二次阻力的作用下磁热生物对流的开始进行了数值研究。修改后的 Darcy-Brinkman-Forchheimer 模型用于驱动控制方程。采用简正模技术和线性稳定性分析来建立特征值问题。利用八阶伽辽金方法从费力的特征值问题中以数值方式提取临界热瑞利数值。垂直通流和二次阻力的力量被认为可以增强热能传递并稳定纳米流体悬浮液，从而试图限制对流过程。磁场强度被确定为延迟磁热生物对流的开始。还发现快速移动的旋转微生物和头重脚轻的纳米流体浓度的存在形成了一个不稳定的系统，加速了磁热生物对流的开始。这项工作的成果可能会在微流体装置、提高石油采收率以及控制对流过程速度的许多其他领域得到应用。