Abstract This article highlights the influence of thermal radiation, inclined magnetic field, and stratification on the third-grade nanofluid with swimming gyrotactic microorganisms. The fluid is flowing past a horizontal cylinder exposed to an inclined magnetic field. The boundary layer system of equations is reconstructed into ordinary differential equations using similarity transformations. The system of equations is resolved using the Optimal Homotopy Analysis Method (OHAM) and the results are visualized numerically and graphically. Physical properties have been taken into consideration and the repercussions of different parameters on these properties are analyzed through contour plots. The following upshots are prominent: (i) radiation augments diffusive energy to the system enhancing the temperature along with the heat transfer rates, (ii) the more inclined magnetic field causes more decrease in velocity (iii) the bioconvective aspect introduced due to the addition of microorganisms altered the transfer rates of microorganisms positively, and (iv) nanoparticles evidently brought down the concentration through Brownian motion effects and the overall influence of these particles hindered mass transport rates.

中文翻译：

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具有游泳微生物的粘弹性纳米流体中能量的辐射传输

摘要 本文重点研究了热辐射、倾斜磁场和分层对具有游动回旋微生物的三级纳米流体的影响。流体流过暴露在倾斜磁场中的水平圆柱体。使用相似变换将边界层方程组重构为常微分方程。方程组使用最优同伦分析方法 (OHAM) 求解，结果以数字和图形方式显示。已考虑物理特性，并通过等高线图分析不同参数对这些特性的影响。以下结果是突出的：（i）辐射增加了系统的扩散能量，提高了温度和传热速率，