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Preparation method and thermal performance of a new ultra-thin flexible flat plate heat pipe 新型超薄柔性平板热管的制备方法和热性能
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2024-01-01 DOI: 10.1615/heattransres.2024051529
Xuancong Zhang, Jinwang Li, Qi Chen
Ultra-thin flat plate heat pipes must provide a degree of flexibility to meet foldable electronics heat dissipation requirements. In this paper, a new flexible ultra-thin flat plate heat pipe with a thickness of 0.75 mm has been designed and fabricated. Compared with the traditional flexible ultra-thin flat heat pipe, the innovation lies in the flexible insulation section formed by epoxy resin pouring of the shell. The design of the shell ensures that the flexible ultra-thin plate heat pipe can respond quickly to the external temperature change, and also has good flexibility, which provides a new choice for the material and structure design of the flexible ultra-thin plate heat pipe shell. The gas-liquid coplanar type mesh is used as the capillary wick to reduce the flow resistance of steam inside the heat pipe, and the wick is hydrophilically modified to improve its capillary pumping performance; a sandwich support structure is used to prevent the steam chamber from collapsing. The thermal performance of the three liquid filling ratios of 0.3, 0.4 and 0.5 was tested at different tilt angles and bending angles. The results show that: in the cases of filling ratios of 0.3, 0.4 and 0.5, the ultra-thin flexible flat plate heat pipe with the liquid filling ratio of 0.3 has the best heat transfer performance under different working conditions; the tilt angle has different effects on the heat transfer performance and starting speed of the ultra-thin flexible flat plate heat pipe with different filling ratios, and the bending angle changes the steam condensation position inside the ultra-thin flexible flat plate heat pipe and increases the thermal resistance.
超薄平板热管必须具有一定的柔韧性,以满足可折叠电子产品的散热要求。本文设计并制作了一种厚度为 0.75 毫米的新型柔性超薄平板热管。与传统的柔性超薄平板热管相比,其创新之处在于外壳由环氧树脂浇注形成的柔性绝缘部分。壳体的设计既保证了柔性超薄板热管对外界温度变化的快速响应,又具有良好的柔韧性,为柔性超薄板热管壳体的材料和结构设计提供了新的选择。采用气液共面型网孔作为毛细管芯,降低蒸汽在热管内的流动阻力,并对毛细管芯进行亲水改性,提高其毛细管抽气性能;采用夹层支撑结构,防止蒸汽腔塌陷。测试了 0.3、0.4 和 0.5 三种液体填充比在不同倾斜角度和弯曲角度下的热性能。结果表明:在充液比为 0.3、0.4 和 0.5 的情况下,充液比为 0.3 的超薄柔性平板热管在不同工况下的传热性能最好;倾角对不同充液比的超薄柔性平板热管的传热性能和启动速度有不同的影响,弯曲角度会改变超薄柔性平板热管内部蒸汽冷凝位置,增加热阻。
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引用次数: 0
Passive thermal management of photovoltaic modules using latent heat storage system with metallic mesh layers and multi-metal spinel oxide nanoparticles 利用带有金属网层和多金属尖晶石氧化物纳米颗粒的潜热储存系统对光伏组件进行无源热管理
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-12-01 DOI: 10.1615/heattransres.2023051462
Emine Yağız Gürbüz, Haytem Moussaoui, Barış Kusun, Azim Dogus Tuncer
Passive thermal management of photovoltaic (PV) panels is an effective and low-cost method for reducing the surface temperature and improving the power output of these systems. In the current study, it is aimed to upgrade the efficiency of a PV system using a latent heat storage system with metallic mesh layers and multi-metal spinel oxide nanoparticles. The experimental part of this work contains two stages. In the first stage, three PV systems including an unmodified PV, LHSS (only paraffin)-integrated PV system and a LHSS-integrated PV system that modified with metallic mesh layers. As a result of the initial test, the PV system with mesh layers added LHSS gave the best performance results. In the second experiment, the mesh integrated LHSS of the PV system has been modified with MgOAl2O3 nanoparticles for enhanced thermal conductivity and compared with the PV system with mesh layer integrated LHSS containing only paraffin. According to the experimental results of this work, applying different types of LHSS configurations significantly reduced the surface temperature of the PV panel. The overall outcomes of the present work showed that using a LHSS with MgOAl2O3 nanoparticles-doped paraffin and metallic mesh layers upgraded the normalized power output efficiency and performance ratio of the unmodified system as 17.43% and 15.72%, respectively.
光伏(PV)电池板的被动热管理是降低表面温度和提高这些系统功率输出的一种有效而低成本的方法。在当前的研究中,目的是利用带有金属网层和多金属尖晶石氧化物纳米颗粒的潜热存储系统来提高光伏系统的效率。这项工作的实验部分包括两个阶段。第一阶段是三个光伏系统,包括未改良的光伏系统、集成了 LHSS(仅石蜡)的光伏系统和集成了金属网层的 LHSS 光伏系统。初步测试结果显示,添加了 LHSS 的网状层的光伏系统性能最佳。在第二次实验中,光伏系统的网状集成 LHSS 被添加了 MgOAl2O3 纳米粒子以增强导热性,并与仅含有石蜡的网状层集成 LHSS 的光伏系统进行了比较。根据这项工作的实验结果,应用不同类型的 LHSS 配置可显著降低光伏板的表面温度。本研究的总体结果表明,使用掺有 MgOAl2O3 纳米颗粒的石蜡层和金属网状层的 LHSS,与未改良系统相比,归一化功率输出效率和性能比分别提高了 17.43% 和 15.72%。
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引用次数: 0
Performance and structure optimization of torsional flow heat exchanger with orthogonal drop-shaped tube 正交滴型管扭转流换热器性能及结构优化
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-12-01 DOI: 10.1615/heattransres.2023051028
Xin Gu, Yiwen Zhu, Xin Liu, Hao Sun, yongqing wang
As a novel variation of shell-and-tube heat exchanger, torsional flow heat exchanger has a promising application prospect, while drop-shaped tube can enhance fluid flow velocity, distribution, and overall heat transfer performance. A torsional flow heat exchanger with orthogonal drop-shaped tubes in the shell side is presented to obtain the benefits of both designs. Three numerical models about torsional flow heat exchangers are established, having the same structure but different in the axial ratio of the heat transfer tubes. The characteristics of fluid flow and heat transfer in the shell side of heat exchangers are analyzed numerically. Response surface method is utilized to optimize the shell-side structure. The results show that compared with the torsional flow heat exchanger with common round tubes, torsional flow heat exchangers with orthogonal drop-shaped tubes of three axial ratios at the Reynolds number range from 5000 to 13000, pressure drop reduces by 9.26%-14.49%, heat transfer coefficient increases by 0.65%-11.57%, and comprehensive performance improves by 14.18%-27.23%. The optimum structure of the torsional flow heat exchanger with orthogonal drop-shaped tubes is predicted by using Minitab and compared to the initial structure, resulting in 17.19% improvement in heat transfer coefficient and 18.63% improvement in comprehensive performance. The study provides a reference for the structural exploration and improvement of torsional flow heat exchangers with enhanced tubes.
扭转流换热器作为管壳式换热器的一种新型变型,具有很好的应用前景,而水滴形管可以提高流体的流速、分布和整体换热性能。介绍了一种壳侧正交滴水管扭转流换热器,得到了两种换热器设计的优点。建立了三种结构相同但换热管轴比不同的扭流换热器数值模型。对换热器壳侧流体流动和换热特性进行了数值分析。采用响应面法对壳侧结构进行优化。结果表明:在5000 ~ 13000雷诺数范围内,三轴比正交水滴形管扭转流换热器与普通圆管扭转流换热器相比,压降降低9.26% ~ 14.49%,换热系数提高0.65% ~ 11.57%,综合性能提高14.18% ~ 27.23%;利用Minitab软件对正交水滴形管扭转流换热器的最优结构进行了预测,并与初始结构进行了比较,传热系数提高了17.19%,综合性能提高了18.63%。该研究为加强管扭转流换热器的结构探索和改进提供了参考。
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引用次数: 0
NATURAL CONVECTION OF NON NEWTONIAN DILATANT FLUID IN THE GAP BETWEEN AN OUTER CYLINDER AND INNER CYLINDER WITH GROOVES 非牛顿流体在带凹槽的外圆柱体和内圆柱体间隙中的自然对流
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-12-01 DOI: 10.1615/heattransres.2023050322
Oussama Benhizia, Mohamed Bouzit
This paper reports a numerical study of the laminar free convection of dilatant fluid between two concentric cylinders. The simulations have been performed for the two dimensional steady state and the ANSYS CFX 16.2 was used for that objective. The governing problem parameters are taken as 1≤n≤1.6, 10≤Pr≤103, 103≤Ra≤105 and different number of grooves added to the inner cylinder (4, 8, 12, 16). We give detailed explanations on the effects of the precedent coefficients on the streamlines, isotherms, velocity and dimensionless temperature. The Rayleigh number strengthens the convective flow which refers by increasing in the Nusselt number at the same set of the other parameters; Also, the important phenomenon here (effects of the grooves) will have a large part from the discussion section. When the grooves accomplished a given number and n is high, the fluid is stiff and the heat transfer mode is purely by conduction.
本文报告了对两个同心圆柱体之间稀释流体层流自由对流的数值研究。模拟是针对二维稳态进行的,为此使用了 ANSYS CFX 16.2。支配问题的参数取为 1≤n≤1.6、10≤Pr≤103、103≤Ra≤105,内圆柱体上添加了不同数量的凹槽(4、8、12、16)。我们详细解释了先例系数对流线、等温线、速度和无量纲温度的影响。雷利数增强了对流,在其他参数设置不变的情况下,对流的对流通过增加努塞尔特数来实现;此外,这里的重要现象(凹槽的影响)将在讨论部分占很大比重。当凹槽达到一定数量且 n 较高时,流体会变得僵硬,热量传递模式将纯粹依靠传导。
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引用次数: 0
STUDY OF FORCED ACOUSTIC OSCILLATIONS INFLUENCE ON METHANE OXIDATION PROCESS IN OXYGEN-CONTAINING FLOW OF HYDROGEN COMBUSTION PRODUCTS 研究强迫声波振荡对含氢燃烧产物氧流中甲烷氧化过程的影响
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-12-01 DOI: 10.1615/heattransres.2023051433
Anastasiya Krikunova, Konstantin Arefyev, Ilya Grishin, Maxim Abramov, Vladislav Ligostaev, Evgeniy Slivinskii, Vitaliy Krivets
The article presents the results of a computational and experimental study of the acoustic intensification of methane oxidation processes in high-enthalpy oxygen-containing flow of hydrogen combustion products. The studies were conducted by using tube with constant cross-section and finite length. Initial specific enthalpy of the oxygen-containing flow is varied from 1600 kJ/kg to 2400 kJ/kg. The patterns of total enthalpy influence of the oxygen-containing flow of hydrogen combustion products and acoustic effect on the efficiency (completeness of chemical reactions) of methane oxidation were obtained. The dependence of acoustic frequency influence on completeness coefficient of physics-chemical processes has been found. The values of fuel equivalence ratio were determined for various total enthalpies of the oxygen-containing flow, corresponding to diffusion and kinetic regimes of methane oxidation. Stability of methane oxidation process and influence of forced acoustic oscillations on the spectral characteristics of static pressure pulsations in the flow were analyzed.
文章介绍了在高焓含氧氢燃烧产物流中甲烷氧化过程声学强化的计算和实验研究结果。研究使用了横截面恒定且长度有限的管道。含氧流的初始比热从 1600 kJ/kg 到 2400 kJ/kg 不等。研究得出了含氧气流对氢燃烧产物的总焓影响以及声波对甲烷氧化效率(化学反应完整性)的影响模式。还发现了声频对物理化学过程完整性系数的影响。根据甲烷氧化的扩散和动力学状态,确定了不同含氧流总焓下的燃料等效比值。分析了甲烷氧化过程的稳定性以及强迫声波振荡对流动中静压脉动频谱特征的影响。
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引用次数: 0
Experimental investigation on thermal performance of ultra-thin flattened heat pipe with middle heating for electronics cooling 用于电子设备冷却的中间加热超薄扁平热管热性能实验研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-12-01 DOI: 10.1615/heattransres.2023051581
Tengqing Liu, Xuehao He, Yaokang Zhang, Shuangfeng Wang
For cooling the electronics in limited space, this study proposes UTFHP with two working modes, i.e., short UTFHP with single-end heating and single-end cooling (SHSC) and long UTFHP with middle heating and dual-end cooling (MHDC). The effects of input head load and cooling temperature on the thermal performance of the short UTFHP with SHSC and long UTFHP with MHDC have been studied for the performance comparison. The input head load ranges from 0-38 W and the cooling temperature ranges from 15 ℃ to 65 ℃. The results show that the two layers wrapped 200 in-1 screen mesh can provide adequate capillary pressure, hence, both of the two UTFHP working modes show good temperature uniformity. The short UTFHP with SHSC shows better thermal performance compared to the performance of long UTFHP with MHDC. In addition, the thermal resistances of both UTFHPs decrease with the increase of the input heat load and the decrease of the cooling temperature under the ranges of operating conditions.
为了在有限的空间内冷却电子设备,本研究提出了具有两种工作模式的UTFHP,即单端加热和单端冷却(SHSC)的短UTFHP和中间加热和双端冷却(MHDC)的长UTFHP。为进行性能比较,研究了输入水头载荷和冷却温度对采用 SHSC 的短型UTFHP 和采用 MHDC 的长型UTFHP 热性能的影响。输入水头载荷范围为 0-38 W,冷却温度范围为 15 ℃ 至 65 ℃。结果表明,两层包裹的 200 in-1 筛网可以提供足够的毛细管压力,因此两种 UTFHP 工作模式都表现出良好的温度均匀性。与带有 MHDC 的长UTFHP 相比,带有 SHSC 的短UTFHP 具有更好的热性能。此外,在工作条件范围内,两种UTHP的热阻都随着输入热负荷的增加和冷却温度的降低而降低。
{"title":"Experimental investigation on thermal performance of ultra-thin flattened heat pipe with middle heating for electronics cooling","authors":"Tengqing Liu, Xuehao He, Yaokang Zhang, Shuangfeng Wang","doi":"10.1615/heattransres.2023051581","DOIUrl":"https://doi.org/10.1615/heattransres.2023051581","url":null,"abstract":"For cooling the electronics in limited space, this study proposes UTFHP with two working modes, i.e., short UTFHP with single-end heating and single-end cooling (SHSC) and long UTFHP with middle heating and dual-end cooling (MHDC). The effects of input head load and cooling temperature on the thermal performance of the short UTFHP with SHSC and long UTFHP with MHDC have been studied for the performance comparison. The input head load ranges from 0-38 W and the cooling temperature ranges from 15 ℃ to 65 ℃. The results show that the two layers wrapped 200 in-1 screen mesh can provide adequate capillary pressure, hence, both of the two UTFHP working modes show good temperature uniformity. The short UTFHP with SHSC shows better thermal performance compared to the performance of long UTFHP with MHDC. In addition, the thermal resistances of both UTFHPs decrease with the increase of the input heat load and the decrease of the cooling temperature under the ranges of operating conditions.","PeriodicalId":50408,"journal":{"name":"Heat Transfer Research","volume":"18 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139055970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Parametric CFD study of Solar Air Heater having alternated upper and bottom absorber plates in turbulent flow 紊流条件下上下板交替吸收体太阳能空气加热器的参数CFD研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-11-01 DOI: 10.1615/heattransres.2023049434
Djemel Hassene, Benmabrouk Amine, Hammami Moez, Baccar Mounir
This work presents a CFD investigation of a Solar Air Heater that features alternating upper and bottom absorber plates to evaluate its thermal behavior and turbulent flow characteristics. Generally, the SAH exhibits low heat transfer characteristics and poor thermal efficiency in turbulent flow. The use of alternating upper and bottom absorber plates facing the turbulent flow would improve heat transfer by producing recirculation zones mainly over these heated plates. The Computational Fluid Dynamics software program, Ansys Fluent 15.0, along with the RNG k-ε turbulence model, was utilized in this analysis to solve the transport equations for turbulent kinetic energy and dissipation rate. The analysis encompassed several geometric and operating parameters, including the range of relative absorber plate length (lp/h) from 4.375 to 140, relative absorber plate height (h/H) ranging from 0.03 to 0.12, and Reynolds numbers varying between 3800 and 18000. The impact of these parameters on heat transfer improvement factors, including the Heat Transfer Amelioration Factor (HTAR), Friction Loss Amelioration Factor (FLAR), and Thermo-Hydraulic Efficiency Factor (THEF), was studied. The optimum computed THEF value was found to be 2.18 for (Lp/h) = 4.375, (h/H) = 0.12, and Re = 3,800
本文介绍了一种具有上下交替吸收板的太阳能空气加热器的CFD研究,以评估其热行为和湍流特性。总的来说,SAH在湍流中表现出较低的传热特性和较差的热效率。使用面对湍流的上下交替吸收板可以通过在这些被加热的板上产生再循环区来改善传热。利用计算流体动力学软件Ansys Fluent 15.0,结合RNG k-ε湍流模型,求解了湍流动能和耗散率的输运方程。分析包括几个几何和操作参数,包括相对吸收板长度(lp/h)范围为4.375至140,相对吸收板高度(h/ h)范围为0.03至0.12,雷诺数范围为3800至18000。研究了这些参数对传热改善因子(包括传热改善因子(HTAR)、摩擦损失改善因子(FLAR)和热水效率因子(THEF)的影响。当(Lp/h) = 4.375, (h/ h) = 0.12, Re = 3800时,计算出的最佳THEF值为2.18
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引用次数: 0
Validating the First Law of Thermodynamics for Unsteady Flow in a Compression Wave Using Mathcad 用Mathcad验证压缩波非定常流动热力学第一定律
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-11-01 DOI: 10.1615/heattransres.2023051072
Vladimir Ryndin, Amangeldy Karmanov, Akmaral Kinzhibekova, Rizagul Dyussova, Gulnara Abdullina
Classical thermodynamics traditionally overlooks the role of quantities dependent on spatial coordinates and time, especially in the context of unsteady flows. This research introduces the first law of thermodynamics (FLT) tailored for non-stationary flow, distinguishing itself with the inclusion of terms bearing partial derivatives of pressure, p(x, t), concerning coordinates and time (–υ(∂р/∂х)dx; –υ(∂р/∂t)dt). By employing this novel approach, the derived equations are validated using a centred compression wave as a representative non-stationary flow case study. A methodology is also presented for experimentally quantifying hydrodynamic energy losses in the intake and exhaust systems of internal combustion engines. Central to the exploration is the calculation of pressure forces' work –υ(∂р/∂х)dx and –υ(∂р/∂t)dt) in the FLT equation for non-stationary flows, particularly their applicability to a centred compression wave. Moreover, a distinct procedure for discerning friction work in non-stationary flow is delineated. The research methods encompass both analytical derivation and numerical simulations leveraging Mathcad software. The bespoke Mathcad program crafted for this study can graphically represent multiple flow parameters as functions of time, proving invaluable for comprehending compression wave dynamics and evaluating friction work in diverse non-steady flows. Ultimately, the incorporation of energy equations tailored for non-stationary flows into classical thermodynamics paves the way for a more comprehensive understanding and application of thermodynamics to intricate flow scenarios.
经典热力学传统上忽略了依赖于空间坐标和时间的量的作用,特别是在非定常流动的情况下。本研究介绍了为非平稳流动量身定制的热力学第一定律(FLT),其区别在于包含包含压力偏导数的项,p(x, t),涉及坐标和时间(-υ(∂r /∂r)dx;υ(∂р/∂t) dt)。通过采用这种新方法,推导出的方程以中心压缩波为代表的非平稳流动案例研究进行了验证。本文还提出了一种实验量化内燃机进气和排气系统中流体动力能量损失的方法。探索的核心是计算非平稳流动的FLT方程中压力的功-υ(∂r /∂r)dx和-υ(∂r /∂t)dt),特别是它们对中心压缩波的适用性。此外,一个独特的程序来识别摩擦功在非平稳流动描述。研究方法包括分析推导和利用Mathcad软件的数值模拟。为这项研究量身定制的Mathcad程序可以用图形表示多种流动参数作为时间的函数,这对于理解压缩波动力学和评估各种非稳定流动中的摩擦功是非常宝贵的。最终,将非平稳流动的能量方程纳入经典热力学,为更全面地理解和应用热力学来解决复杂的流动问题铺平了道路。
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引用次数: 0
Effect of radiation absorption and chemical reaction on MHD‐free convective flow through a porous medium past an infinite vertical porous plate in the presence of constant heat flux 恒定热通量下辐射吸收和化学反应对多孔介质中无MHD对流的影响
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-17 DOI: 10.1002/htj.22936
N. Ahmed, Richa Deb Dowerah
An incompressible, electrically conducting, and viscous fluid flowing steadily and freely across a uniformly porous media that is partially constrained by an infinitely long vertical porous plate is studied in the present article. Additionally, chemical reaction and radiation absorption effects are seen. Here, a magnetic field of uniform strength is applied transversely to the plate, a normal suction velocity is imposed on the fluid, and the heat flux is considered to be constant. The non‐dimensional momentum and energy equations are solved using the method of perturbation. The problem has been analytically resolved, and several parameters, including the Hartmann number, porosity parameter, thermal Grashof number, mass Grashof number, and transport properties like the Sherwood number, skin friction, and plate temperature, are graphically represented. The current study reveals a spike in the radiation absorption effect causes skin friction to drop, but on the other hand, a contrary effect is observed for plate temperature. One of the notable findings of this investigation is that the Sherwood number increases as chemical reaction parameter influence increases.
本文研究了一种不可压缩的、导电的粘性流体稳定自由地流过均匀多孔介质,该介质部分受无限长垂直多孔板的约束。此外,还观察到化学反应和辐射吸收效应。在这里,在板的横向上施加均匀强度的磁场,对流体施加正常的吸力速度,并且认为热流密度是恒定的。用摄动法求解了非量纲动量方程和能量方程。这一问题已经得到了解析解决,包括Hartmann数、孔隙度参数、热Grashof数、质量Grashof数以及Sherwood数、表面摩擦和板温等输运性质在内的几个参数都用图形表示了出来。目前的研究表明,辐射吸收效应的峰值会导致皮肤摩擦下降,但另一方面,对板温观察到相反的效果。本研究的一个显著发现是舍伍德数随化学反应参数影响的增加而增加。
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引用次数: 0
Study of weakly nonlinear double‐diffusive magnetoconvection under concentration modulation 浓度调制下弱非线性双扩散磁对流的研究
IF 1.7 4区 工程技术 Q3 THERMODYNAMICS Pub Date : 2023-08-16 DOI: 10.1002/htj.22939
Atul Jakhar, Anand Kumar, Vinod K. Gupta
This article explains the heat and mass transfer of electrically conducting Newtonian fluid in double‐diffusive magnetoconvective flow. We have considered two infinite horizontal plates at a constant distance apart under the concentration‐modulated boundary condition. A constant magnetic field is considered in vertically upward directions, which generates an induced magnetic field. We have used the weakly nonlinear analysis to obtain the heat and mass transfer rate using the Ginzburg–Landau equation. The software MATHEMATICA is used to determine the solution of the Ginzburg–Landau equation by inbuilt function. The effects of physical parameters that occurred in the study on the Nusselt number and Sherwood number have been examined graphically. Modulation has a negligible effect on the threshold value of the thermal Rayleigh number, that is, on stationary convection. Moreover, it was found that the Chandrasekhar number, magnetic‐Prandtl number, amplitude of modulation, and frequency of modulation are proportional to the heat and mass transports.
本文解释了双扩散磁对流中导电牛顿流体的传热传质。在浓度调制边界条件下,我们考虑了两个距离恒定的无限大水平板。考虑垂直向上的恒定磁场,产生感应磁场。本文采用弱非线性分析方法,利用金兹堡-朗道方程求出了传热传质速率。利用MATHEMATICA软件通过内置函数确定了金兹堡-朗道方程的解。对研究中出现的物理参数对努塞尔数和舍伍德数的影响进行了图解检验。调制对热瑞利数阈值的影响可以忽略不计,即对静止对流的影响。此外,还发现钱德拉塞卡数、磁普朗特数、调制幅度和调制频率与热输运和质量输运成正比。
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引用次数: 1
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Heat Transfer Research
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