Abstract A rotating MHD flow of electrically conducting Oldroyd-B fluid through non-Darcy porous medium across a stretching/shrinking surface is investigated in purview of bioconvection effects. The fluid velocity field, temperature field, concentration of nano materials and that of bio microorganisms have been simultaneously formulated in the form of coupled nonlinear partial differential equations. The quest for improved thermal performance in practicable situations has motivated to utilize some real fluids like Oldroyd-B nanofluids with support from bioconvection effect to stabilize nanoparticle fraction. The zero normal flux of the nanoparticles and convective boundary condition are imposed. The substitution of appropriate similarity functions has resulted a set of ordinary differential equations (ODE). The sparse system of transformed ODEs was simulated numerically with bvp4c solver facilitated by MATLAB commercial software. Computations were executed for specific parameters to perceive the response of velocity, temperature, concentration of nanoparticles and concentration of microorganisms, skin friction coefficient and local heat transfer rate with variation of influential parameters. It is detected that fluid temperature profile rises when Deborah number, Biot number, parameters for buoyancy ratio, porosity, rotation, magnetic field strength, thermophoresis diffusion are enhanced.

中文翻译：

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生物对流对水平拉伸旋转框架中 Oldroyd-B 纳米流体 MHD 流动影响的数值模拟

摘要 在生物对流效应的范围内研究了导电 Oldroyd-B 流体通过非达西多孔介质穿过拉伸/收缩表面的旋转 MHD 流。流体速度场、温度场、纳米材料浓度和生物微生物浓度已同时以耦合非线性偏微分方程的形式表示。在实际情况下对提高热性能的追求促使人们利用一些真实的流体，如 Oldroyd-B 纳米流体，并在生物对流效应的支持下稳定纳米颗粒部分。施加了纳米粒子的零法向通量和对流边界条件。适当的相似性函数的替代产生了一组常微分方程 (ODE)。使用 MATLAB 商业软件辅助的 bvp4c 求解器对变换 ODE 的稀疏系统进行了数值模拟。对特定参数进行计算，以感知速度、温度、纳米颗粒浓度和微生物浓度、皮肤摩擦系数和局部传热率随影响参数变化的响应。检测到当Deborah数、Biot数、浮力比参数、孔隙率、旋转度、磁场强度、热泳扩散等参数增加时，流体温度分布升高。表皮摩擦系数和局部传热率随影响参数的变化。检测到当Deborah数、Biot数、浮力比参数、孔隙率、旋转度、磁场强度、热泳扩散等参数增加时，流体温度分布升高。表皮摩擦系数和局部传热率随影响参数的变化。检测到当Deborah数、Biot数、浮力比参数、孔隙率、旋转度、磁场强度、热泳扩散等参数增加时，流体温度分布升高。