Purpose

According to the previous research, bioconvection has been recognized as an important mechanism in current engineering and environmental systems. For example, researchers exploit this mechanism in modern green bioengineering to develop environmentally friendly fuels, fuel cells and photosynthetic microorganisms. This study aims to analyse how this type of convection affects the flow behaviour and heat transfer performance of mixed convection stagnation point flow in alumina-copper/water hybrid nanofluid. Also, the impact of a modified magnetic field on the boundary layer flow is considered.

Design/methodology/approach

By applying appropriate transformations, the multivariable differential equations are transformed into a specific sort of ordinary differential equations. Using the bvp4c procedure, the adjusted mathematical model is revealed. Once sufficient assumptions are provided, multiple solutions are able to be produced.

Findings

The skin friction coefficient is declined when the nanoparticle concentration is increased in the opposing flow. In contrast, the inclusion of aligned angles displays an upward trend in heat transfer performance. The presence of several solutions is established, which simply leads to a stability analysis, hence verifies the viability of the initial solution.

Originality/value

The current findings are unique and novel for the investigation of mixed bioconvection flow towards a vertical flat plate in a base fluid with the presence of hybrid nanoparticles.

中文翻译：

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氧化铝-铜/水中的混合生物对流驻点流向垂直板

目的

根据以往的研究，生物对流已被公认为当前工程和环境系统中的重要机制。例如，研究人员在现代绿色生物工程中利用这种机制来开发环保燃料、燃料电池和光合微生物。本研究旨在分析这种类型的对流如何影响氧化铝-铜/水混合纳米流体中混合对流驻点流动的流动行为和传热性能。此外，还考虑了修改磁场对边界层流动的影响。

设计/方法/方法

通过应用适当的变换，多变量微分方程被变换为特定种类的常微分方程。使用 bvp4c 程序，显示调整后的数学模型。一旦提供了足够的假设，就可以产生多种解决方案。

发现

当纳米粒子浓度在反向流动中增加时，皮肤摩擦系数下降。相比之下，包含对齐的角度显示传热性能呈上升趋势。建立了几个解决方案的存在，这简单地导致了稳定性分析，因此验证了初始解决方案的可行性。

原创性/价值

目前的研究结果对于研究混合生物对流流向存在混合纳米颗粒的基础流体中的垂直平板是独特而新颖的。