检索结果-内蒙古大学图书馆

mhd nanofluid flow with energy transfer over a porous stretching surface by using a second-grade fluid model

NUMERICAL HEAT TRANSFER PART A-APPLICATIONS 2025年第5期86卷 1313-1327页

作者： Dey, Debasish Borah, Rupjyoti Dibrugarh Univ Dept Math Dibrugarh 786004 Assam India Tingkhong Coll Dept Math Dibrugarh 786612 Assam India

The main attention of this research is to examine the nature of the flow behavior of nanofluids and energy transfers past an expanding sheet with second-grade fluid model. The system is also situated in an absorbent area, which affects the effects of heat and mass transport and chemical reaction. The numerical calculations and visualization for various flow parameters are performed using a finite difference code that is developed in the built-in bvp4c solver scheme of MATLAB. This involves adopting a set of new variables to change the character of the governing equations of this study. To the best of the authors' knowledge, many authors have contributed to this field, but they do not take into account the above fluid model associated with the energy transfers with the influences of Brownian motion, thermophoresis effect, and chemical reaction parameters, etc., in their study. Major findings of this study is to achieve a higher amount of thermal transference using the physical parameters, such as magnetic, visco-elastic, thermophoresis, and Brownian motion parameters, etc. Also, using smaller values of the magnetic parameter can be an effective way to minimize the impact of drag force of the fluid at the surface. The considering fluid model has multifarious industrial applications, such as food and cosmetic industry and pharmaceutical and biomedical industry, etc., due to its versatile rheological characteristics.

关键词： Heat transfer mass transfer mhd nanofluid second-grade fluid stretching surface

来源：评论

学校读者我要写书评

暂无评论

mhd modelling of the near-sun evolution of coronal mass ejection initiated from a sheared arcade

引用

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 2025年第4期538卷 2569-2578页

作者： Cai, Jinnan Zhang, Ling Jiang, Chaowei Yan, Kuo Feng, Xueshang Zuo, Pingbing Wang, Yi Harbin Inst Technol Sch Aerosp Sci Shenzhen Key Lab Numer Predict Space Storm Shenzhen 518055 Peoples R China

Coronal mass ejections (CMEs) are phenomena in which the Sun suddenly releases a mass of energy and magnetized plasma, potentially leading to adverse space weather. Numerical simulation provides an important avenue for comprehensively understanding the structure and mechanism of CMEs. Here, we present a global-corona mhd simulation of a CME originating from sheared magnetic arcade and its interaction with the near-Sun solar wind. Our simulation encompasses the pre-CME phase with gradual accumulation of free magnetic energy (and building up of a current sheet within the sheared arcade) as driven by the photospheric shearing motion, the initiation of CME as magnetic reconnection commences at the current sheet, and its subsequent evolution and propagation to around 0.1 au. A twisted magnetic flux rope (MFR), as the main body of the CME, is created by the continuous reconnection during the eruption. By interacting with the ambient field, the MFR experiences both rotation and deflection during the evolution. The CME exhibits a typical three-part structure, namely a bright core, a dark cavity, and a bright front. The bright core is mainly located at the lower part of the MFR, where plasma is rapidly pumped in by the high-speed reconnection outflow. The dark cavity contains both outer layer of the MFR and its overlying field that expands rapidly as the whole magnetic structure moves out. The bright front is formed due to compression of plasma ahead of the fast-moving magnetic structure. Future data-driven modeling of CME will be built upon this simulation with real observations used for the bottom boundary conditions.

关键词： mhd methods: numerical Sun: Magnetic fields Sun: Flares Sun: corona Sun: coronal mass ejections

来源：评论

学校读者我要写书评

暂无评论

mhd rotating flow of a viscous fluid with heat sink and Prabhakar fractional derivative

引用

INTERNATIONAL JOURNAL OF MODERN PHYSICS B 2025年第0期

作者： Sarwar, Noman Asjad, Muhammad Imran Almusawa, Musawa Yahya Univ Management & Technol Dept Math Lahore 54770 Pakistan Jazan Univ Fac Sci Dept Math Jizan Saudi Arabia

The unsteady hydromagnetic free convection flow of rotating incompressible viscous fluids across an infinite moving plate with fractional thermal transportation is explored in the presence of heat source, Hall current and slip velocity effects. The Laplace transform method is used to convert the controlling PDEs corresponding to the temperature and velocity profiles into linear ODEs. To get the results, the classical model is modified to a fractional-order model using constitutive relations of the generalized Fourier's law for heat flux. After making the equations dimensionless, solutions to the energy and velocity equations may be found. Graphs are plotted to check the insight of physical characteristics. Moreover, the Mittag-Leffler kernel is most affected. The memory of temperature improved by using generalized Mittag-Leffler kernel in comparison of exponential kernel. Some graphical representations of the temperature and velocity were created using the software application Mathcad. As a result, it is found that with the application of a generalized Mittag-Leffler kernel, the thermal and momentum boundary layers as well as the memory of fluid properties can be enhanced for larger values of the fractional parameter.

关键词： mhd damped thermal Prabhakar fractional approach slip and hall current

来源：评论

学校读者我要写书评

暂无评论

mhd Free convective and radiative flow under the influence of thermal diffusion and heat sink considering ramped temperature and ramped concentration

引用

RADIATION EFFECTS AND DEFECTS IN SOLIDS 2025年

作者： Ahmed, Nazibuddin Bormudoi, Mridusmita Cotton Univ Dept Math Gauhati India Assam Downtown Univ Fac Sci Dept Math Gauhati India

The principal objective of the current investigation is to explore the impacts of thermo-diffusion on an unsteady mhd-free convective flow of a viscous, incompressible fluid passing through a suddenly started vertical semi-infinite plate in the presence of chemical reaction, thermal radiation, and heat sink. This article examines ramped temperatures and ramped concentrations. The basic boundary conditions are made non-dimensional by inserting some non-dimensional components. The Laplace transform method is used to solve the partial differential equations in closed form. Graphical illustrations of the influence of various flow parameters on the velocity, temperature, and concentration fields are given. Fluctuations in skin friction, the Nusselt number, and the Sherwood number for various parameters are explored. Increased Soret number boosts fluid velocity and concentration in both ramped and isothermal conditions. The ramped parameter drops fluid temperature and concentration but accelerates the fluid velocity. The rate of momentum transfer, heat transfer, and mass transfer improve as the ramped parameter value rises.

关键词： mhd Soret effect chemical reaction heat sink ramped temperature ramped concentration

来源：评论

学校读者我要写书评

暂无评论

mhd slip flow of ethylene glycol and water mixture based Al2O3 nanofluids between micro-parallel plates

引用

CASE STUDIES IN THERMAL ENGINEERING 2025年 68卷

作者： Simsek, Hatice Tekirdag Namik Kemal Univ Vocat Sch Tech Sci Tekirdag Turkiye

The rapid growth of MEMS (micro-electromechanical systems) has led to increasing importance of determining the momentum and heat transfer properties of fluids in micro-scale mhd flow. The aim of this study is to determine how to remove the heat generated during the operation of MEMS from the system and how to affect the heat transfer by dispersing ethylene glycol-water mixture based Al2O3 nanoparticles at different particle volume concentrations in the presence of a magnetic field to minimize the heating in these devices. Calculations were made for 0 %, 4 % and 8 % nanoparticle volume ratios, 0, 0.02, 0.04 liquid layer thickness-nanoparticle radius ratios, 1 and 2 Hartman number values and 0:100, 50:50 and 100:0 ethylene glycol (EG)/water volume ratios. When the results are examined, the highest average Nu number values are achieved in 100:0 % EG/W used as the base fluid. Within the investigated ranges, 100:0 % EG/W provides maximum heat transfer rate improvement of approximately 0.54 % and 1.41 % over 0:100 % EG/W, respectively. Therefore, it was found that 100:0 % EG/W based Al2O3 nanofluid can be used as a suitable alternative method to remove the heat generated by MEMS (micro-electromechanical systems) during operation and minimize the heating in these devices.

关键词： Slip flow Nanofluids Ethylene glycol Water mhd Nusselt number

来源：评论

学校读者我要写书评

暂无评论

Thermal and flow dynamics of unsteady mhd nanofluid convection in a partially heated porous cavity

引用

JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY 2025年 1-16页

作者： Vigneshwari, S. Reddappa, B. Sumithra, A. Kumar, B. Rushi Oztop, Hakan F. Kalasalingam Acad Res & Educ Sch Adv Sci Dept Math Virudunagar 626126 Tamil Nadu India Vellore Inst Technol Sch Adv Sci Dept Math Vellore 632014 Tamil Nadu India Firat Univ Technol Fac Dept Mech Engn Elazig Turkiye China Med Univ China Med Univ Hosp Dept Med Res Taichung Taiwan Chandigarh Univ Univ Ctr Res & Dev UCRD Mohali 140413 Punjab India

This study numerical investigates unsteady freeconvection in a square permeable cavity, driven by magnetohydrodynamic flow of TiO2-H2O nanofluid. The cavity features partially heated vertical walls, with adiabatic bottom and inclined upper walls, a scenario with widespread applications in fields such as heating, ventilation, and air conditioning (HVAC), electronic cooling, solar collectors, building insulation, automotive engineering, geothermal energy, and aerospace technology. The governing equations are discretized using the Marker and Cell (MAC) method, with spatial discretization achieved through the finite difference technique. A staggered grid system is employed to enhance stability and accuracy, and the resulting equations are solved iteratively to capture the unsteady behavior of the *** study examines the range of Darcy number 10-1 <= Da <= 10-3,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left( {10<^>{ - 1} \le {\text{Da}} \le 10<^>{ - 3} } \right),$$\end{document} Rayleigh number 103 <= Ra <= 106,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left( {10<^>{3} \le {\text{Ra}} \le 10<^>{6} } \right),$$\end{document} Hartmann number 10 <= Ha <= 30,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left( {10 \le Ha \le 30} \right),$$\end{document} Prandtl number Pr=6.2,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage

关键词： Nanofluid Porous cavity Natural convection mhd Numerical simulation Heat source/sink

来源：评论

学校读者我要写书评

暂无评论

Irreversibility and heat transfer analysis in mhd Darcy-Forchheimer flow of Casson hybrid nanofluid flow through cone and wedge

引用

NUMERICAL HEAT TRANSFER PART A-APPLICATIONS 2025年第1期86卷 174-200页

作者： Jayavel, Prakash Upreti, Himanshu Tripathi, Dharmendra Pandey, Alok Kumar Avvaiyar Govt Coll Women Dept Math Karaikal Ut Of Puducherr India BML Munjal Univ SoET Gurugram Haryana India Graph Era Hill Univ Dept Math Dehra Dun India Natl Inst Technol Dept Math Srinagar Uttaranchal India Graph Era Deemed be Univ Dept Math Dehra Dun India Graph Era Deemed be Univ Dept Math Dehra Dun 248002 India

This model investigates the irreversibility and heat transfer assessment of mhd induced Darcy-Forchheimer flow of Casson hybrid nanofluid through cone and wedge regime. A mathematical model is established to describe the flow behavior of the hybrid nanofluid under the effects of significant physical parameters. Numerical simulation of the model has been done through bvp4c solver. A comparative analysis for the velocity field between mono nanofluid (Sodium Alginate based MoS2 nanofluid) and hybrid nanofluid (Sodium Alginate based MoS2-GO nanofluid) have been presented. Another comparative analysis for isotherms for Cone and Wedge regimes is also done. In the results, various key parameters like magnetic field strength, Casson fluid parameter, the Forchheimer parameter, and the Brinkman number are taken into consideration. Findings demonstrate that the magnetic field and Forchheimer term significantly affects the irreversibility and heat transfer behavior of the Casson hybrid nanofluid through the cone and wedge regime.

关键词： Casson hybrid nanofluid cone Darcy-Forchheimer flow irreversibility mhd wedge regime

来源：评论

学校读者我要写书评

暂无评论

Application of a Soft-Switching Adaptive Kalman Filter for Over-Range Measurements in a Low-Frequency Extension of mhd Sensors

引用

AEROSPACE 2025年第3期12卷 192-192页

作者： Tong, Junze Shi, Shaocen Wang, Fuchao Tian, Dapeng Chinese Acad Sci Changchun Inst Opt Fine Mech & Phys Changchun 130033 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

The increasing demand for image quality in aerospace remote sensing has led to higher performance requirements for inertial stabilization platforms equipped with image sensors, particularly in terms of bandwidth. To achieve wide-bandwidth control in optical stabilization platforms, engineers employ magneto-hydrodynamic (mhd) sensors as key components to enhance system performance because of their wide measurement bandwidth (5-1000 Hz). While mhd sensors offer a wide-frequency response, they are limited by a narrow measuring range and low sensitivity at low frequencies, making them unsuitable as standalone sensors. To address the challenges of over-range measurement and the loss of low-frequency signals, in this study, we developed a soft-switching adaptive Kalman filter method, which enables us to dynamically adjust the fusion weights in the Kalman filter so we can obtain wide-band measurement signals even when the mhd sensor experiences over-range conditions. The proposed method was validated with fusion experiments involving a fiber-optic gyroscope and an mhd sensor;the results demonstrate its ability to expand the sensing bandwidth, regardless of the operating conditions of the mhd sensor.

关键词： mhd adaptive law Kalman filter inertial sensors data fusion

来源：评论

学校读者我要写书评

暂无评论

引用

NUMERICAL HEAT TRANSFER PART B-FUNDAMENTALS 2025年第5期86卷 1398-1413页

作者： Razzaq, Raheela Farooq, Umer Harbin Inst Technol HITSZ Sch Mech Engn & Automat Shenzhen Peoples R China Harbin Engn Univ Coll Math Sci Harbin Heilongjiang Peoples R China

This article presents non-similar analysis of Tiwari-Das hybrid nanofluid flow toward the exponentially expanding/shrinking sheet. Aluminum oxide (Al2O3) and copper (Cu) nanoparticles have been dispersed in the water. The significance of viscous dissipation, thermal radiation, magnetic fields, and heat sources has been observed in this work. A mathematical system is transmuted into a dimensionless, non-similar form by the utilization of non-similar transformations. The non-similar partial differential system is simulated by employing local non-similarity up to the 3rd order of iteration via bvp4c. The significance of flow constraints versus energy and velocity profiles is demonstrated through figures and tables. The fluid velocity decreases with expanding magnetic field (M) and injection parameters (S). Energy profile grows as radiation (Rd) and heat generating (Q) parameter increases. The thermal profile is thought to be diminished by an expansion in the Prandtl number (Pr). Stretching parameter (lambda) increases cause a reduction in the temperature profile, whereas the heat profile grows as the Eckert parameter (Ec) increases. For particular values of the skin friction (Cf) and Nusselt number (Nu), numerical values are produced using local similarity and local non-similarity approaches. The findings indicate that skin friction decreases as the magnetic parameter (M) rises, but an expansion of the Prandtl number creates a growth in the Nusselt number. Excellent agreement between the current work and the published article is discovered in limiting cases.

关键词： bvp4c exponentially expanding sheet hybrid nanofluid mhd non-similar analysis thermal radiation viscous dissipation

来源：评论

学校读者我要写书评

暂无评论

Cattaneo-Christov heat flux in mhd Ree-Eyring nanofluid flow via porous medium including entropy optimization and gyrotactic microorganism

引用

JOURNAL OF THE KOREAN PHYSICAL SOCIETY 2025年第7期86卷 615-635页

作者： Vinodkumar Reddy, M. Nath, Jintu Mani Reddy, K. Ramakrishna Das, Tusar Kanti Reddy, K. Venugopal Malla Reddy Engn Coll Autonomous Dept Math Secunderabad 500100 India Mangaldai Coll Dept Math Mangaldai 784125 India CMR Inst Technol Dept Math Hyderabad 501401 India Dudhnoi Coll Dept Math Dudhnoi 783124 Assam India Anurag Univ Dept Math Hyderabad 500088 India

The proposed study aims to perform an extensive numerical analysis of the Cattaneo-Christov heat flux model for the magnetohydrodynamic (mhd) flow of Ree-eyring nanofluid through a Darcy-Forchheimer porous medium. This analysis will integrate the effects of Activation energy, gyrotactic microorganisms, entropy optimization, Brownian motion, and Thermophoresis, with a particular focus on the dynamics of flow over a stretching surface. Utilizing the Buongiorno nanofluid model, the research will explore the complex interactions within fluid flow. This investigation is pioneering in its approach, as it combines intricate factors such as heat flux modelling, non-Newtonian fluid behaviour, entropy generation, microbial dynamics, and nano-model effects into a unified numerical framework. By addressing these multifaceted elements, the study aims to advance the understanding of heat and mass transfer in sophisticated fluid systems. The ongoing investigation is conducted using a numerical approach using the bvp5c MATLAB package. The findings are expected to enhance thermal management strategies across diverse applications, including aerospace engineering, electronic cooling, energy systems, and biomedical technologies. It is observed that The Cattaneo-Christov heat flux model, considering finite thermal relaxation, reduces heat distribution promptly. Furthermore, enhanced Lorentz force, Brownian motion, and radiation diffuse heat significantly, while thermophoresis and activation energy boost mass distribution. Also, Increased Peclet and bioconvection Lewis numbers lead to higher motile density due to stronger convection and thermal diffusion. The entropy generation also looks promising with the enhancement in Lorentz force, diffusion factor, Brinkman number, and temperature difference factor.

关键词： mhd Ree-Eyring nanofluid Darcy-Forchheimer Cattaneo-Christov heat flux Entropy generation Binary chemical reaction Microorganisms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：