A finite element study is provided in this paper for the controlling of the flow and heat transfer fields by multiporous fins within U-shaped enclosures using a semi-implicit technique for the intermediate velocities. Three porous fins are located in the left, center, and right channels of the U-shaped domain, and a heated section with a changeable length is placed in the lower boundary of the irregular domain. The overall thermal conductivity is a combination of the thermal conductivity of the nanofluid, porous medium, and thermal dispersion. Both an electromagnetic force and a heat source/sink take place in the flow domain. The unsteadiness of dependent variables is treated using the characteristic-based split algorithm. The major outcomes revealed that various flow structures and thermal features are given as the length of the porous fins is changed. Also, an increase in the length of the heat source B causes all the fins to be placed over the heated section, hence there are three maximum values of Nu_s at the higher values of B. Furthermore, the average Nusselt number is reduced by 36.5% as Ha is increased from 0 to 100.

中文翻译：

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多发热多孔翅片对倾斜 U 形外壳内纳米流体的流动结构和热场的影响：有限元方法模拟

本文提供了一项有限元研究，用于使用半隐式技术控制中间速度，通过 U 形外壳内的多孔翅片控制流动和传热场。三个多孔翅片位于U形域的左、中、右通道，在不规则域的下边界放置一个长度可变的加热段。总热导率是纳米流体、多孔介质和热分散的热导率的组合。电磁力和热源/热汇都发生在流域中。使用基于特征的分裂算法处理因变量的不稳定。主要结果表明，随着多孔翅片长度的变化，给出了各种流动结构和热特征。此外，增加了热源的长度B使所有翅片都放置在加热部分上，因此在B的较高值处有三个 Nu _s最大值。此外，随着 Ha 从 0 增加到 100，平均努塞尔数减少了 36.5%。