Department of Mathematics, Quaid-i-Azam University, Islamabad, Pakistan.
Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
J Appl Biomater Funct Mater. 2022 Jan-Dec;20:22808000221120329. doi: 10.1177/22808000221120329.
Entropy is the measure of the amount of energy in any physical system that is not accessible for the useful work, which causes a decrease in a system's thermodynamic efficiency. The idea of entropy generation analysis plays a vital role in characterizing the evolution of thermal processes and minimizing the impending loss of available mechanical power in thermo-fluid systems from an analytical perspective. It has a wide range of applications in biological, information, and engineering systems, such as transportation, telecommunication, and rate processes. The analysis of the entropy generation of axisymmetric magnetohydrodynamic hybrid nanofluid /water flow induced by rotating and stretching cylinder in the presence of heat radiation, ohmic heating, and the magnetic field is focus of this study. Thermal energy transport of hybrid nanofluids is performed by applying the Maxwell model. Heat transport is carried out by using convective boundary condition. The dimensionless ordinary differential equations are acquired by similarity transformations. The numerical solution for these differential equations is obtained by the program in MATLAB. A comparison between nanofluid and hybrid nanofluid is made for flow field, temperature, and entropy generation. Comparison of nanofluid flow with hybrid nanofluid flow exhibits a higher rate of heat transmission, while entropy generation exhibits the opposite behavior. It is observed that the flow and heat distribution increase as the solid volume fraction's value grows. An increase in entropy is indicated by augmentation in the Brinkman number and temperature ratio parameter, but the Bejan number shows a declining trend. Furthermore, outcomes of the Nusselt number for hybrid nanofluid and nanofluid are calculated for various parameters. It is noticed that the Nusselt number is reduced for enlarging the magnetic field and Eckert number. The axial and azimuthal wall stress parameters are declined by augmenting the Reynolds number.
熵是衡量任何物理系统中不可用于有用功的能量量的指标，这导致系统热力学效率降低。熵产生分析的思想在从分析角度描述热过程的演化和最小化热流体系统中可用机械功率的潜在损失方面起着至关重要的作用。它在生物、信息和工程系统中具有广泛的应用，例如运输、电信和速率过程。本研究的重点是分析轴对称磁流体混合纳米流体/水在旋转和拉伸圆柱存在热辐射、欧姆加热和磁场时的流动引起的熵产生。通过应用 Maxwell 模型来进行混合纳米流体的热能传输。通过使用对流边界条件来进行热传输。通过相似变换获得无量纲常微分方程。这些微分方程的数值解通过 MATLAB 中的程序获得。对流动场、温度和熵产生进行了纳米流体和混合纳米流体之间的比较。与纳米流体流动的比较表明，混合纳米流体流动具有更高的传热速率，而熵产生则表现出相反的行为。观察到随着固体体积分数值的增加，流动和热分布增加。随着 Brinkman 数和温度比参数的增加，熵增加，而 Bejan 数呈下降趋势。此外，还计算了各种参数下混合纳米流体和纳米流体的努塞尔数。注意到随着磁场和埃克特数的增加，努塞尔数减小。通过增加雷诺数，轴向和周向壁应力参数减小。
