The present article investigates the flow and heat transfer of Sisko nanofluid over a permeable vertical stretching surface in a porous medium. The effect of buoyancy, suction, and viscous dissipation has been taken into account. Buongiorno’s model of nanofluid consisting of thermophoresis and Brownian diffusion has been considered. Moreover, zero nanoparticle mass flux condition is employed at the boundary which leads to a more realistic physical problem. Using a suitable transformation governing partial differential equations of fluid flow are transformed into a set of nonlinear ordinary differential equations (ODEs). The numerical solution of nonlinear ODEs are obtained using the finite difference technique in MATLAB. The influence of physical parameters viz. buoyancy parameter (λ*), porosity parameter (β*), thermophoresis parameter (Nt*), suction parameter (f), Sisko material parameter (A*), Brinkman number (Br*), Brownian diffusion parameter (Nb*) and Lewis number (Le*) on velocity, temperature and nanoparticle volume fraction are shown graphically. Moreover, to understand the physical phenomenon in the boundary layer region, the numerical values of skin friction and Nusselt number are calculated and presented through table values. It has been found that the Brownian diffusion has a negligible impact on Nusselt number relative to the results obtained in previous studies, where nanoparticle volume fraction on the boundary was actively controlled. The obtained results disclose that the buoyancy parameter increases the velocity of fluid while it reduces the temperature. Suction parameter reduces both velocity and temperature, whereas the porosity parameter reduces velocity and enhances the temperature and nanoparticle volume fraction.


中文翻译：

---

浮力和吸力对具有质量流量条件的多孔介质中垂直拉伸片上Sisko纳米流体的影响

本文研究了Sisko纳米流体在多孔介质中的可渗透垂直拉伸表面上的流动和传热。已经考虑了浮力，吸力和粘性耗散的影响。已经考虑了Buongiorno的由热泳和布朗扩散组成的纳米流体模型。而且，在边界处采用零纳米粒子质量通量条件，这导致更现实的物理问题。使用适当的变换，控制流体流动的偏微分方程被变换为一组非线性常微分方程（ODE）。使用MATLAB中的有限差分技术获得了非线性ODE的数值解。物理参数的影响。浮力参数（λ*），孔隙度参数（β*），热泳参数（Nt *），吸力参数（f），Sisko材料参数（A *），布林克曼数（Br *），布朗扩散参数（Nb *）和路易斯数（Le *在速度，温度和纳米颗粒体积分数上的图示。此外，为了了解边界层区域中的物理现象，计算并通过表值给出了皮肤摩擦力和努塞尔数的数值。已经发现，相对于先前研究中得到的结果，布朗扩散对Nusselt数的影响可忽略不计，在先前的研究中，边界上的纳米粒子体积分数受到主动控制。获得的结果表明，浮力参数增加了流体的速度，同时降低了温度。吸力参数会降低速度和温度，而孔隙率参数会降低速度并提高温度和纳米颗粒的体积分数。