The flow of electrically conducting micropolar fluid past an exponentially permeable shrinking sheet in the presence of a magnetic field and thermal radiation is studied. Similarity transformations are applied to the governing partial differential equations to form ordinary differential equations. The solution for the resultant equations, subject to boundary conditions, is then computed numerically using the bvp4c solver in MATLAB. The effects of several parameters on the local skin friction coefficient, couple stress, Nusselt number, velocity, microrotation and temperature of the fluid are analysed. Because the numerical computations for this problem result in triple solutions, stability analysis is carried out to ascertain the stability and significance of these solutions. The first solution is revealed to be stable, hence more physically meaningful than the other solutions. Meanwhile, it is found that the increase in magnetic and thermal radiation parameters reduces the fluid temperature.

中文翻译：

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具有热辐射的指数收缩片上微极流体的磁流体动力学边界层流动：三重解和稳定性分析

研究了在存在磁场和热辐射的情况下导电微极流体流过指数渗透性收缩片。相似变换应用于控制偏微分方程以形成常微分方程。然后使用 MATLAB 中的 bvp4c 求解器以数值方式计算所得方程的解，受边界条件的影响。分析了几个参数对局部表面摩擦系数、耦合应力、努塞尔数、速度、微旋转和流体温度的影响。由于此问题的数值计算会产生三重解，因此进行稳定性分析以确定这些解的稳定性和重要性。第一个解决方案被证明是稳定的，因此比其他解决方案更具物理意义。同时，发现磁和热辐射参数的增加降低了流体温度。