Heat transfer intensification in hydromagnetic and radiative 3D unsteady flow regimes: A comparative theoretical investigation for aluminum and γ-aluminum oxides nanoparticles

Abstract

This article investigates the colloidal study for water and ethylene glycol based nanofluids. The effects of Lorentz forces and thermal radiation are considered. The process of non-dimensionalities of governing equations is carried out successfully by means of similarity variables. Then, the resultant nonlinear nature of flow model is treated numerically via Runge-Kutta scheme. The characteristics of various pertinent flow parameters on the velocity, temperature, streamlines and isotherms are discussed graphically. It is inspected that the Lorentz forces favors the rotational velocity and rotational parameter opposes it. Intensification in the nanofluids temperature is observed for volumetric fraction and thermal radiation parameter and dominating trend is noted for γ-aluminum nanofluid. Furthermore, for higher rotational parameter, reverse flow is investigated. To provoke the validity of the present work, comparison between current and literature results is presented which shows an excellent agreement. It is examined that rotation favors the velocity of the fluid and more radiative fluid enhances the fluid temperature. Moreover, it is inspected that upturns in volumetric fraction improves the thermal and electrical conductivities.

摘要

本文研究了水和乙二醇基纳米流体的胶体性质。考虑了洛伦兹力和热辐射的影响, 通过相似变 化, 完成了控制方程的无量纲转化。然后, 应用龙格-库塔法, 对流动模型的非线性特性进行数值分 析, 对有关流速、温度、流线、等温线等流动参数的特性进行图解分析。结果表明, 洛伦兹力有利于 旋转速度, 不利于其他旋转参数。体积分数和热辐射参数对Al 和γ-Al₂O₃ 纳米流体的温度有正相关强 化作用。此外, 对于较高的旋转参数, 研究其反向流动问题。与文献结果进行了比较, 结果显示具有 较高的吻合度。旋转有利于流体的流动速度, 辐射流体越多, 流体温度越高, 而且体积分数的增加提 高了热导率和电导率。