T. Armaghani, A. M. Rashad, Hussein Togun, M. A. Mansour, T. Salah
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The average Nusselt number is increased when the volume friction of hybrid nanofluids increases. Additionally, as the dimensionless heat source length <i>B</i> rises, the rate of heat generation rises as well, enhancing the buoyancy force while reducing the impact of shear-driven force. The left heater’s dimensionless position, <i>D</i> = 0.7, exhibits the largest local Nu in contrast to other occurrences. It was found that the minimum Nu occurred at the heat generation/absorption coefficient <i>Q</i> = − 8 at the lowest wall of the enclosure because the intensity of the isothermal formed at the upper wall of the enclosure was greater than that at the bottom of the enclosure in comparison to other cases. The results also showed that, due to the irreversibility of magnetic force, which is one of the main processes for heat transmission, isentropic lines diffuse toward the interior of the enclosure as porosity decreases. On the surface of the enclosure’s vertical left wall (<i>Y</i>-axis at <i>X</i> = 0), the Nu shows as symmetrical profiles, and it can be seen that the Nu increases as the wave length of the wavy walls diminishes. The effects of the Hartmann number and Darcy number on streamlines and isothermal temperature are also investigated.</p>","PeriodicalId":49063,"journal":{"name":"Iranian Journal of Science and Technology-Transactions of Mechanical Engineering","volume":"18 1","pages":""},"PeriodicalIF":1.5000,"publicationDate":"2024-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Hybrid Nanofluid Unsteady MHD Natural Convection in an Inclined Wavy Porous Enclosure with Radiation Effect, Partial Heater and Heat Generation/Absorption\",\"authors\":\"T. Armaghani, A. M. Rashad, Hussein Togun, M. A. Mansour, T. 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引用次数: 0
摘要
本研究以数值方法研究了在多孔介质混合纳米流体填充的波浪形围墙中的流动和对流传热成分。在恒定的倾斜磁场和热辐射(Rd)作用下,流动被视为浮力驱动。空腔左壁部分受热,右壁波浪形冷却,其他壁绝热。为了表达结果,使用了流线、等温线和 Nu。分析确定了热辐射 (Rd)、哈特曼数 Ha、倾斜磁场、左加热器的无量纲位置 (D)、热源的无量纲长度 (B) 以及混合纳米流体的体积分数对传热的影响。当混合纳米流体的体积摩擦增大时,平均努塞尔特数也随之增大。此外,随着无量纲热源长度 B 的增加,发热率也随之增加,从而增强了浮力,同时降低了剪切力的影响。与其他情况相比,左侧加热器的无量纲位置 D = 0.7 显示出最大的局部 Nu。研究发现,Nu 最小值出现在外壳最低壁的发热/吸热系数 Q = - 8 处,因为与其他情况相比,外壳上壁形成的等温强度大于外壳底部的等温强度。结果还显示,由于磁力的不可逆性(磁力是热量传递的主要过程之一),等熵线随着孔隙率的降低向外壳内部扩散。在外壳垂直左壁表面(Y 轴在 X = 0 处),Nu 呈对称剖面,可以看出 Nu 随着波浪壁波长的减小而增大。此外,还研究了哈特曼数和达西数对流线和等温温度的影响。
Hybrid Nanofluid Unsteady MHD Natural Convection in an Inclined Wavy Porous Enclosure with Radiation Effect, Partial Heater and Heat Generation/Absorption
In this study, the flow and heat transfer components of convection are numerically investigated in a hybrid nanofluid-filled, porous-medium enclosure with wavy walls. The flow is considered to be buoyancy-driven under a constant inclined magnetic field and heat radiation (Rd). The cavity is partially heated from its left wall and is cooled by its wave-like right wall while the other walls are adiabatic. To express the results, streamlines, isothermal, and the Nu are used. Analysis is done to determine how heat transfer is affected by thermal radiation (Rd), the Hartmann number Ha, the inclined magnetic field, the left heater’s dimensionless location (D), the heat source’s dimensionless length (B), and the hybrid nanofluid’s volume fraction. The average Nusselt number is increased when the volume friction of hybrid nanofluids increases. Additionally, as the dimensionless heat source length B rises, the rate of heat generation rises as well, enhancing the buoyancy force while reducing the impact of shear-driven force. The left heater’s dimensionless position, D = 0.7, exhibits the largest local Nu in contrast to other occurrences. It was found that the minimum Nu occurred at the heat generation/absorption coefficient Q = − 8 at the lowest wall of the enclosure because the intensity of the isothermal formed at the upper wall of the enclosure was greater than that at the bottom of the enclosure in comparison to other cases. The results also showed that, due to the irreversibility of magnetic force, which is one of the main processes for heat transmission, isentropic lines diffuse toward the interior of the enclosure as porosity decreases. On the surface of the enclosure’s vertical left wall (Y-axis at X = 0), the Nu shows as symmetrical profiles, and it can be seen that the Nu increases as the wave length of the wavy walls diminishes. The effects of the Hartmann number and Darcy number on streamlines and isothermal temperature are also investigated.
期刊介绍:
Transactions of Mechanical Engineering is to foster the growth of scientific research in all branches of mechanical engineering and its related grounds and to provide a medium by means of which the fruits of these researches may be brought to the attentionof the world’s scientific communities. The journal has the focus on the frontier topics in the theoretical, mathematical, numerical, experimental and scientific developments in mechanical engineering as well
as applications of established techniques to new domains in various mechanical engineering disciplines such as: Solid Mechanics, Kinematics, Dynamics Vibration and Control, Fluids Mechanics, Thermodynamics and Heat Transfer, Energy and Environment, Computational Mechanics, Bio Micro and Nano Mechanics and Design and Materials Engineering & Manufacturing.
The editors will welcome papers from all professors and researchers from universities, research centers,
organizations, companies and industries from all over the world in the hope that this will advance the scientific standards of the journal and provide a channel of communication between Iranian Scholars and their colleague in other parts of the world.