International Journal of Heat and Fluid Flow最新文献_第6页

Geometry-induced enhancement of capillary wicking in porous strips: Experimental and analytical insights 几何诱导的增强毛细管排芯在多孔条：实验和分析的见解

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-24 DOI: 10.1016/j.ijheatfluidflow.2025.110221

Srirama Chandra Murthy Rampally, Navneet Kumar

This study explores the influence of varying cross-sectional geometries on the capillary-driven wicking of water in vertically suspended Whatman filter paper strips. By extending the classical Lucas–Washburn framework through a Darcy-based model with spatially varying cross-sectional area

A (z)

, we analyze how geometry impacts both penetration length and advancing front velocity. The empirical power-law relationship

h = a t^{b}

was used to quantify penetration kinetics. Experimentally, the exponent

b

increased from

0.53

in rectangular strips to

0.59

and

0.54

in exponential and hyperbolic geometries, respectively, demonstrating improved wicking due to shape-induced modulation of viscous resistance. Velocity comparisons show that at a height of

20 m m

, front velocities in exponential and hyperbolic cases were

14 %

and

27 %

higher than trapezoidal, while at

50 m m

, the trapezoidal geometry outperformed others by

34 %

and

50 %

over exponential and hyperbolic shapes, respectively. A central element of this enhancement is the dimensionless viscous resistance term

f

, which captures how geometry influences the wicking. Unlike the constant

f

in rectangular strips, exponential and hyperbolic profiles exhibit a smooth, monotonic increase in

f

, reducing cumulative resistance and supporting sustained wicking. In contrast, the trapezoidal geometry displays a peak in

f

at

z^{*} = 1 - e^{- 1}

for an aspect ratio of

0.083

, leading to a transient benefit. These findings not only align with theoretical predictions but also demonstrate how strategic geometric tapering can substantially enhance capillary transport. The work holds practical significance for wick design in microfluidic diagnostics, passive cooling, and liquid delivery systems.

本研究探讨了不同的横截面几何形状对垂直悬浮的Whatman滤纸条中毛细管驱动的水芯的影响。通过将经典的Lucas-Washburn框架扩展为一个基于darcy的模型，该模型具有空间变化的横截面积a (z)，我们分析了几何形状如何影响穿透长度和推进锋面速度。采用经验幂律关系h=atb来量化渗透动力学。实验中，指数b从矩形条的0.53分别增加到指数和双曲线几何的0.59和0.54，表明由于形状诱导的粘性阻力调制而改善了排芯。速度比较表明，在20mm高度时，指数型和双曲线型的锋面速度分别比梯形高14%和27%，而在50mm高度时，梯形的锋面速度分别比指数型和双曲线型高34%和50%。这种增强的核心要素是无量纲粘性阻力项f，它捕捉几何形状如何影响芯。与矩形条中的常数f不同，指数型和双曲线型曲线表现出平滑的、单调的f增加，减少了累积阻力并支持持续的排芯。相反，当纵横比为0.083时，梯形几何结构在z * =1-e-1处显示出f的峰值，从而带来了短暂的好处。这些发现不仅与理论预测一致，而且还证明了战略性几何变细如何大大增强毛细管运输。这项工作对微流体诊断、被动冷却和液体输送系统的芯设计具有实际意义。

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引用次数: 0

Numerical investigation of heat transfer characteristics of supercritical carbon dioxide in a spiral heat exchanger 超临界二氧化碳在螺旋换热器内换热特性的数值研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-23 DOI: 10.1016/j.ijheatfluidflow.2025.110215

Siyu Gao, Xiaohong Hao, Yan Wang, Xiangsheng Zheng

Supercritical carbon dioxide (SCO₂) has emerged as a novel working fluid in nuclear power generation systems due to its unique thermophysical properties and potential system efficiency advantages. In this study, numerical investigations of heat transfer characteristics of SCO₂ in a vertical helical tube were conducted under conditions of pressures ranging from 15 to 20 MPa, inlet temperatures from 453 to 483 K, and mass fluxes from 297.16 to 866.44 kg/m²s. The SST k-ω turbulence model and pseudo-transient method were employed to simulate the heat transfer process. The effects of mass flux, inlet temperature, pressure drop, buoyancy, and flow acceleration on the heat transfer coefficient were analyzed. The results indicated that at high mass fluxes, the influence of vortices and secondary flows becomes more pronounced, decreasing heat transfer efficiency. Increasing the inlet temperature can reduce the fluid flow resistance, enhancing the heat transfer coefficient. As pressure increases, the fluid density increases and the fluid inertia force grows, offsetting part of the viscous force and reducing pressure drop and friction factor. Finally, to accurately predict the heat transfer of SCO₂ in a spiral heat exchanger, a new heat transfer correlation was proposed.

超临界二氧化碳（SCO2）由于其独特的热物理性质和潜在的系统效率优势，已成为核能发电系统中的一种新型工质。在压力为15 ~ 20 MPa、进口温度为453 ~ 483 K、质量通量为297.16 ~ 866.44 kg/m2s的条件下，对垂直螺旋管内SCO2的换热特性进行了数值研究。采用SST k-ω湍流模型和拟瞬态方法模拟了换热过程。分析了质量通量、进口温度、压降、浮力和流动加速度对换热系数的影响。结果表明，在高质量通量时，涡流和二次流的影响更为明显，降低了换热效率。提高进口温度可以降低流体的流动阻力，提高换热系数。随着压力的增大，流体密度增大，流体惯性力增大，抵消了部分粘性力，降低了压降和摩擦系数。最后，为了准确预测螺旋换热器中SCO2的换热，提出了一种新的换热关系式。

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引用次数: 0

Exploration of the stability and evolution characteristics of thermocapillary convection of shear-thinning fluids in rectangular cavity 矩形空腔剪切减薄流体热毛细对流稳定性及演化特征探讨

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-23 DOI: 10.1016/j.ijheatfluidflow.2025.110219

Xiaoming Zhou , Haocun Wang , Wang Leilei , Yanni Jiang

To analyze the oscillation and evolution characteristics of thermocapillary convection instability of non-Newtonian fluids, the effect of power-law index on the critical transition process and oscillation evolution is investigated systematically, in which the power-law model is adopted to describe the rheological properties of the fluid. It is found that the transition time from steady single vortex flow (SUF) to unsteady hydrothermal waves (HTW) varied with the power-law index, being initially governed by the effective viscosity. For the periodic oscillation regime, the number of vortical cells decreases and their size increases as power-law index decreases. The transient apparent viscosity of non-Newtonian fluids exhibits a clear periodic fluctuation with time. A decrease in the power-law index tends to destabilize the flow, whereas an increase in the consistency coefficient enhances flow stability. For Ma ≥ Ma_cr (Ma, Marangoni number), thermocapillary convection manifests periodic oscillations with multiple evolving vortices, a lower power-law index diminishes the critical temperature difference, amplifies the amplitude of velocity oscillations, and induces larger time-series irregularity.

为了分析非牛顿流体热毛细对流不稳定性的振荡和演化特征，系统地研究了幂律指数对临界过渡过程和振荡演化的影响，其中采用幂律模型来描述流体的流变特性。研究发现，从稳定单涡流（SUF）到不稳定热液波（HTW）的过渡时间随幂律指数的变化而变化，最初受有效粘度的支配。在周期振荡状态下，随着幂律指数的减小，涡胞的数量减少，尺寸增大。非牛顿流体的瞬态表观粘度随时间有明显的周期性波动。幂律指数的减小会使流动失稳，而一致性系数的增大会增强流动的稳定性。当Ma≥Macr （Ma， Marangoni数）时，热毛细对流表现为多个涡演化的周期振荡，幂律指数越低，临界温差减小，速度振荡幅度越大，时间序列不规则性越大。

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引用次数: 0

Insight into effect of internal heating on natural convection of Rivlin–Ericksen fluid with highly permeable porous medium: Dynamical system approach 内部加热对高渗透多孔介质Rivlin-Ericksen流体自然对流影响的研究：动力系统方法

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-22 DOI: 10.1016/j.ijheatfluidflow.2025.110212

Anupama Singh , Anand Kumar , Vinod K. Gupta

The current article explores the structure of chaotic convection and the rate of heat transfer in a Rivlin–Ericksen fluid layer with an internal heat source flowing through a highly permeable porous medium that is heated from below. The truncated Galerkin approximation has produced a low-dimensional system similar to the Lorenz model. To compute the numerical simulation for a Lorenz-like equation framework, we implemented the fourth-order Runge–Kutta method. We utilized MATHEMATICA software for quantitative analysis and MATLAB software for visualization. The influence of an internal heat content on chaotic convection has been investigated. Additionally, when comparing only the elasticity effect, we found that the Rayleigh number decreases by 8.09%. This indicates that the chaotic behavior predominates over the instability of the system. We discovered that both the level of internal heat and the elastic parameter enhance chaotic convection. We propose that the level of internal heat influences the transition from steady to chaotic convection.

本文探讨了具有内部热源的Rivlin-Ericksen流体层中混沌对流的结构和传热速率，该流体层流经从下方加热的高渗透性多孔介质。截断的伽辽金近似产生了一个类似于洛伦兹模型的低维系统。为了计算类洛伦兹方程框架的数值模拟，我们实现了四阶龙格-库塔方法。采用MATHEMATICA软件进行定量分析，MATLAB软件进行可视化分析。研究了内部热含量对混沌对流的影响。此外，当仅比较弹性效应时，我们发现瑞利数降低了8.09%。这表明混沌行为在系统的不稳定性中占主导地位。我们发现内热水平和弹性参数都增强了混沌对流。我们提出内部热的水平影响从稳定对流到混沌对流的转变。

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引用次数: 0

Enhanced cooling performance in turbine blade tip U-channel using protrusion-V-rib composite structure 采用凸型- v型肋复合结构增强涡轮叶片u型通道冷却性能

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-20 DOI: 10.1016/j.ijheatfluidflow.2025.110218

Zhen Xiang , Qilong Liu , Shaohua Han , Shizhen Qi , Tianyi Huo , Runsheng Zhang , Leping Zhou , Li Li , Hui Zhang , Xiaoze Du

Improving the cooling effectiveness of turbine blade squealer tip regions under high thermal loads remains a challenge in designing of gas turbines. This study numerically investigates the cooling performance of a novel protrusion-V-rib composite structure applied to the internal U-channel near the blade squealer tip. Eight configurations, including holed/hole free designs and combinations of V-ribs, protrusions and vanes, are evaluated at Re = 10,000–50,000. Key findings show that holed structures enhance heat transfer near holes due to accelerated fluid velocity and increased turbulence, resulting in higher Nusselt number. However, hole free configurations exhibit superior downstream heat transfer (up to 4.14 % improvement) by maintaining coolant mass flow. Complex geometries, particularly the V-Convex design, significantly suppress flow separation and reduce vortex size by promoting fluid disturbance and turbulence. The V-convex structure exhibits the highest Nusselt number and comprehensive thermal performance factor under both constant temperature and constant heat flux boundary conditions, confirming its robustness. The results highlight the trade-off between local heat transfer enhancement (holed structures) and downstream cooling effectiveness (hole-free designs), emphasizing the importance of geometric optimization for blade squealer tip cooling. This work helps understand the composite cooling structures and provides insights for efficient thermal management in applications of high-temperature turbines.

在高热负荷条件下，如何提高涡轮叶片尖尖区域的冷却效率一直是燃气轮机设计中的难题。本文对一种新型的凸型- v型肋复合结构应用于靠近叶片尖部的u型通道内的冷却性能进行了数值研究。在Re = 10,000-50,000的条件下，对8种结构进行了评估，包括有孔/无孔设计以及v型肋、凸点和叶片的组合。关键发现表明，由于流体速度加快和湍流增加，孔结构增强了孔附近的传热，从而导致更高的努塞尔数。然而，通过保持冷却剂质量流量，无孔结构表现出优越的下游传热（提高4.14%）。复杂的几何形状，特别是v -凸设计，通过促进流体扰动和湍流，显著抑制了流动分离，减小了旋涡尺寸。在恒温和恒热流边界条件下，v -凸结构的Nusselt数和综合热性能因子均最高，证实了其鲁棒性。结果强调了局部传热增强（孔结构）和下游冷却效率（无孔设计）之间的权衡，强调了几何优化对叶片尖叫器尖端冷却的重要性。这项工作有助于了解复合冷却结构，并为高温涡轮机应用中的有效热管理提供见解。

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引用次数: 0

Isolating the specific contribution of boundary-layer edge chemical nonequilibrium to stagnation-point heating 分离了边界层边缘化学不平衡对停滞点加热的特殊贡献

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-20 DOI: 10.1016/j.ijheatfluidflow.2025.110206

Sangdi Gu

This study, for the first time, systematically quantifies the specific impact of stagnation point boundary layer (BL) edge nonequilibrium on surface heating for arbitrary BLs by decoupling the problem. Stagnation point heat flux theory is used in conjunction with a quasi-one-dimensional stagnation streamline model, in which the BL edge state is precisely controlled: pressure, enthalpy, and velocity gradient are held constant while chemical composition is varied between the frozen and equilibrium limits. It is found that nonequilibrium at the edge has no effect on heat flux when the wall is super-catalytic, the flow is equilibrated, or the recombination rate is sufficiently fast to maintain the atomic mass fraction at the wall unchanged despite variations at the BL edge. If the Lewis number (

L e

) is not equal to 1 in these scenarios, edge nonequilibrium may moderately influence the heat flux by up to approximately

\pm 20 %

, although

L e \approx 1

is likely a good approximation. In contrast, edge nonequilibrium can significantly affect the heat flux if the wall is non-catalytic and chemistry in the BL is slow, regardless of

L e

. These results contribute significantly to theoretical understanding of high-enthalpy stagnation-point heating and enable clearer interpretation of full-fidelity simulations under various scenarios.

本文首次通过解耦的方法，系统地量化了驻点边界层边缘不平衡对任意驻点边界层表面加热的具体影响。将驻点热流密度理论与准一维停滞流线模型相结合，精确控制BL边缘状态：压力、焓和速度梯度保持不变，而化学成分在冻结极限和平衡极限之间变化。研究发现，当壁面超催化、流动平衡或复合速率足够快时，壁面原子质量分数保持不变，壁面的非平衡状态对热流密度没有影响。如果在这些情况下路易斯数（Le）不等于1，则边缘不平衡可能对热通量产生大约±20%的中等影响，尽管Le≈1可能是一个很好的近似值。相反，如果壁面不具有催化作用，且壁面内的化学反应较慢，则边缘不平衡会显著影响热流密度。这些结果有助于对高焓滞点加热的理论理解，并使各种情景下的全保真模拟更清晰地解释。

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引用次数: 0

Effect of fin-enhanced microchannel structures on flow and heat transfer: comparison of triangular ribbed and corrugated designs 翅片增强微通道结构对流动和传热的影响：三角肋和波纹设计的比较

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-19 DOI: 10.1016/j.ijheatfluidflow.2025.110213

Juhui Chen , Shuxiang Pang , Dan Li , Liwei Chen , Michael Zhurakov , Siarhei Lapatsin , Wenrui Jiang

Conventional microchannels typically exhibit limited heat transfer efficiency and suboptimal flow characteristics. This study investigates two fin-enhanced microchannel geometries, triangular ribbed and corrugated, using a moving-grid method to simulate periodic fin motion. Numerical simulations were conducted over a Reynolds number range of 50–250 at a fin oscillation frequency of 20 Hz. The results show that the triangular ribbed microchannel offers lower flow resistance and improved overall flowability due to its relatively smoother flow path, whereas the corrugated design produces stronger flow disturbances and secondary vortices, leading to enhanced heat transfer, especially at lower Reynolds numbers. However, the intensified flow mixing in the corrugated microchannel also increases flow-path tortuosity, resulting in a larger pressure drop. To evaluate the overall performance, the Performance Evaluation Criterion (PEC) was used. The triangular ribbed channel achieved a maximum PEC of 1.52 at Re = 200, indicating a balanced improvement in both heat transfer and flow resistance. These geometries are relevant for practical thermal management applications, such as compact heat sinks and miniaturized cooling devices, due to their manufacturability and effectiveness in enhancing thermo-fluidic performance.

传统的微通道通常表现出有限的传热效率和次优的流动特性。本研究研究了两种鳍增强微通道几何形状，三角形肋形和波纹形，使用移动网格方法模拟周期性鳍运动。在50 ~ 250雷诺数范围内，在20 Hz的翅片振荡频率下进行了数值模拟。结果表明，三角形肋形微通道由于其相对平滑的流动路径，具有更低的流动阻力和更高的整体流动性，而波纹设计产生更强的流动扰动和二次涡，导致传热增强，特别是在低雷诺数时。然而，波纹微通道内流动混合的加剧也增加了流道扭曲度，导致更大的压降。采用性能评价标准（PEC）对整体性能进行评价。在Re = 200时，三角形肋形通道的最大PEC达到1.52，表明传热和流动阻力的平衡改善。由于其可制造性和提高热流体性能的有效性，这些几何形状与实际热管理应用相关，例如紧凑型散热器和小型化冷却装置。

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引用次数: 0

A review on the asymmetry, steady instability and bistability in the wake of industrial ground vehicles 工业地面车辆尾迹的不对称性、稳态不稳定性和双稳定性研究进展

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-19 DOI: 10.1016/j.ijheatfluidflow.2025.110208

Olivier Cadot

Since the first observation of steady symmetry breaking in the turbulent wakes of a square-back Ahmed body by Grandemange et al. (2012), there have been reports of similar effects with ground vehicles of more complex geometries with square-back style, including real vehicles. The article reviews these cases of industrial flows, either at small or full scale in wind tunnels or numerical simulations with and without road effects. A clear consensus appears of asymmetric recirculating flows in the vertical direction that can, with well chosen parametric variations, reverse to the opposite asymmetry and sometimes lead to spectacular vertical bistable dynamics. These global changes of the base flow impact the body drag and lift. The underlying universal property of these wakes is likely the same steady instability as that of the square-back Ahmed body.

自从Grandemange等人（2012）首次观察到方形后置Ahmed体湍流尾迹中的稳定对称性破坏以来，已经有报道称，具有方形后置风格的更复杂几何形状的地面车辆（包括真实车辆）也有类似的效果。本文回顾了这些工业流动的案例，无论是在风洞中的小尺度或全尺度，还是在有或没有道路影响的情况下的数值模拟。一个明确的共识是，在垂直方向上的非对称再循环流动，可以通过精心选择的参数变化，逆转到相反的不对称，有时会导致壮观的垂直双稳态动力学。这些基流的整体变化影响了机体的阻力和升力。这些尾迹潜在的普遍特性很可能与阿迈德的方背体一样具有稳定的不稳定性。

引用次数: 0

Thermodynamic analysis of nanofluid with aggregated and non-aggregated nanoparticles 聚集和非聚集纳米颗粒纳米流体的热力学分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-19 DOI: 10.1016/j.ijheatfluidflow.2025.110205

Yasir Akbar , Keren Li , Jamshaid Iqbal , Xin Yang , Xuerui Mao

Regenerative cooling using nanofluids has been shown to improve the thermal performance of rocket engine thrust chambers and nozzle walls substantially. This study examines the use of a kerosene-alumina (

A l_{2} O_{3}

) nanofluid as an innovative coolant for semi- cryogenic rocket engines, emphasizing its superior thermophysical properties relative to conventional coolants, despite constraints in high-temperature environments. The focus is to analyze the thermodynamic behavior of nanofluid incorporating both aggregated and non-aggregated

A l_{2} O_{3}

nanoparticles. To capture nanoparticles aggregation, modified Krieger-Dougherty and Maxwell-Bruggeman models are integrated into the formulation. The complex influences such as Hall current and flow through porous media are also taken into consideration. The governing equations with thermal and velocity slip boundary conditions are simplified using the lubrication approximation to enable efficient analysis and numerically simulated to collect reference datasets across eight nanofluid configurations. A machine learning employing Bayesian Regularization Back Propagation Scheme (BRBPS) is developed using partitioned simulation data (70 % training, 15 % testing, 15 % validation). Aggregated and non-aggregated nanofluids reveal similar patterns in entropy generation and velocity profiles. However, non-aggregated nanoparticles result in more thermodynamic irreversibility than aggregated nanoparticles when the conditions are the same. Bejan number decreases with higher permeability. Both aggregated and non-aggregated nanoparticles compress trapped bolus size with increasing nanoparticles volume fraction.

利用纳米流体进行再生冷却已被证明可以显著改善火箭发动机推力室和喷嘴壁面的热性能。本研究考察了煤油-氧化铝（Al2O3）纳米流体作为半低温火箭发动机的创新冷却剂的使用，强调了其相对于传统冷却剂的优越热物理性能，尽管在高温环境中受到限制。重点是分析纳米流体的热力学行为，包括聚集和非聚集的Al2O3纳米颗粒。为了捕捉纳米颗粒的聚集，改进的Krieger-Dougherty和Maxwell-Bruggeman模型被整合到配方中。同时考虑了霍尔电流和多孔介质流动等复杂影响。利用润滑近似简化了具有热和速度滑移边界条件的控制方程，以便进行有效的分析和数值模拟，以收集八种纳米流体配置的参考数据集。使用分割的模拟数据（70%训练，15%测试，15%验证）开发了采用贝叶斯正则化反向传播方案（BRBPS）的机器学习。聚集和非聚集的纳米流体在熵生成和速度分布方面显示出相似的模式。然而，在相同的条件下，非聚集的纳米颗粒比聚集的纳米颗粒产生更大的热力学不可逆性。随着渗透率的增加，Bejan数减少。随着纳米颗粒体积分数的增加，聚集和非聚集的纳米颗粒都压缩了被捕获颗粒的尺寸。

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引用次数: 0

Comparative analysis of passive thermal management of lithium-ion batteries in diverse climatic conditions 不同气候条件下锂离子电池被动热管理的对比分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-19 DOI: 10.1016/j.ijheatfluidflow.2025.110179

Mohd Bilal , Shanza Kiant , Kasra Ghasemi , Syeda Humaira Tasnim , Shaikh Hasibul Majid , Shohel Mahmud

Battery thermal management is a key factor in ensuring the safety, performance, and longevity of lithium-ion batteries, particularly in high-power applications such as electric vehicles. Excessive temperature rise and uneven thermal distribution can lead to accelerated degradation, reduced efficiency, and increased safety risks, necessitating the implementation of effective thermal regulation strategies. This study introduces a promising approach to battery thermal management by integrating phase change materials and thermoelectric coolers, evaluated through a combination of numerical simulations using COMSOL Multiphysics software and experimental validation. The research examines the thermal performance of four PCMs − RT35, RT31, n-octadecane, and coconut oil under varying charging rates (2C and 3C), each selected for its distinct melting temperature and thermal properties. Results demonstrate that the peak temperature of the battery pack at a 3C charging rate can be effectively maintained at 34.5 °C, with a maximum temperature difference among battery cells of less than 0.5 °C, ensuring thermal uniformity. The study identifies n-octadecane as the optimal PCM due to its superior latent heat capacity and balanced melting point, enabling it to maintain safe battery temperatures across diverse operating conditions.

电池热管理是确保锂离子电池安全性、性能和寿命的关键因素，特别是在电动汽车等高功率应用中。过高的温升和不均匀的热分布会导致加速降解、降低效率和增加安全风险，因此需要实施有效的热调节策略。本研究介绍了一种将相变材料和热电冷却器集成在一起的电池热管理方法，并通过COMSOL Multiphysics软件的数值模拟和实验验证进行了评估。该研究考察了四种PCMs——RT35、RT31、正十八烷和椰子油在不同充电速率（2C和3C）下的热性能，每种PCMs都根据其不同的熔化温度和热性能进行选择。结果表明，在3C充电速率下，电池组的峰值温度可有效维持在34.5℃，电池单体间最大温差不超过0.5℃，保证了热均匀性。该研究将正十八烷确定为最佳PCM，因为它具有优越的潜热容量和平衡的熔点，使其能够在各种操作条件下保持安全的电池温度。

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引用次数: 0