International Journal of Heat and Mass Transfer最新文献_第5页

Effect of wall thickness on heat flow conditions in directed energy deposition 定向能沉积中壁厚对热流条件的影响

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-23 DOI: 10.1016/j.ijheatmasstransfer.2026.128414

Shenliang Yang , Alexander D. Goodall , Xiaoliang Jin , Xiao Shang , Yu Zou , Lova Chechik

Heat flow conditions vary significantly in Directed Energy Deposition (DED), such as during the repair of structures with varying cross sections. While classical thermal analyses emphasize conduction, heat losses through convection and radiation can be consequential in thin-wall geometries. This can lead to certain geometries experiencing heat accumulation with build height, while in other geometries, the temperature decreases as the build height increases. To quantify how heat flow mechanisms vary with wall thickness, in this study, in-situ coaxial monitoring was combined with a finite element (FE) model that accounts for conduction, convection, and radiation. Measured melt pool thermal intensities during the deposition of 9 Inconel 718 walls with thicknesses ranging from thin- to thick-wall regimes are compared with FE-based predictions. The results show that conduction is the dominant heat transfer mechanism between the melt pool and the surrounding materials in all cases during deposition; however, convective and radiative losses of the melt pool are non-negligible in thin-wall regimes, being responsible for up to 35 % of the total heat losses. Meanwhile, the relative importance of convection/radiation of the melt pool was found to increase as sections narrow. In addition, the minimum heat loss of the melt pool (and the maximum thermal intensity) was observed at an intermediate wall thickness (2.1 mm), while the total heat losses of the melt pool increased by 39 % in a 1.1 mm wall thickness and by 17 % in a 9.1 mm wall thickness. These strongly non-linear thermal relationships lead to the conclusion that samples wider than 4 mm can be treated as “bulk”, for which conduction-dominated assumptions are adequate in thermal analysis; sections with a thickness less than 4 mm require convection and radiation to be considered. These findings could provide guidance in the selection of deposition parameters and modeling assumptions to ensure consistent DED repairs across highly variable cross-sections.

在定向能沉积（DED）中，热流条件变化很大，例如在具有不同截面的结构的修复过程中。虽然经典的热分析强调传导，但在薄壁几何形状中，对流和辐射的热损失可能是必然的。这可能导致某些几何形状随着建筑高度的增加而经历热量积累，而在其他几何形状中，温度随着建筑高度的增加而降低。为了量化热流机制随壁厚的变化，本研究将原位同轴监测与考虑传导、对流和辐射的有限元（FE）模型相结合。测量了9种厚度从薄壁到厚壁的Inconel 718壁沉积过程中的熔池热强度，并与基于fe的预测结果进行了比较。结果表明：在沉积过程中，热传导是熔池与周围材料之间的主要传热机制；然而，在薄壁条件下，熔池的对流和辐射损失是不可忽略的，占总热损失的35%。同时，对流/辐射的相对重要性随着截面的缩小而增加。此外，在中等壁厚（2.1 mm）时，熔池的最小热损失（和最大热强度）被观察到，而在1.1 mm壁厚时，熔池的总热损失增加了39%，在9.1 mm壁厚时增加了17%。这些强烈的非线性热关系导致的结论是，样品的宽度大于4毫米可以被视为“体”，其中传导主导的假设是充分的热分析；厚度小于4毫米的截面需要考虑对流和辐射。这些发现可以为沉积参数的选择和建模假设提供指导，以确保在高度可变的截面上进行一致的DED修复。

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引用次数: 0

Enhanced boiling heat transfer in silicon-based heat sinks with hybrid jet/gradient-density-pin-fin-microchannel 混合射流/梯度-密度-针鳍-微通道硅基散热器中沸腾传热的增强

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-30 DOI: 10.1016/j.ijheatmasstransfer.2026.128423

Xia Hua, Huiying Wu, Jinya Liu, Zhenyu Liu

To enhance boiling heat transfer for ultra-high heat flux dissipation in chips, silicon-based heat sinks with hybrid jet/gradient-density-pin-fin-microchannel are proposed. Specifically, hybrid jet/uniform-pin-fin-microchannel (JUPM, serving as a control case without gradient density design), hybrid jet/dense-to-sparse-pin-fin-microchannel (JDPM), and hybrid jet/sparse-to-dense-pin-fin-microchannel (JSPM) are fabricated. By combining a data acquisition system with a high-speed microscope camera, the heat transfer performance, boiling flow patterns, pressure drop and coefficient of performance (COP) of deionized water in JUPM, JDPM, JSPM across a range of jet velocities (V_j = 1.5, 2, 2.5 m/s) and inlet subcoolings (ΔT_sub = 30, 50, 70°C) are experimentally investigated. The results are further benchmarked against those from the heat sink with hybrid jet/continuous-microchannel (JCM), revealing that: 1) JSPM, JDPM and JUPM all improve the critical heat flux (CHF) due to the enhanced liquid supply to the heating surface (caused by the suppressed reverse flow and capillary-driven liquid bridges). Moreover, JSPM further increases the CHF compared to JDPM and JUPM due to the presence of more liquid bridges downstream. Particularly, JSPM achieves the highest CHF of 1464 W/cm² when V_j = 2.5 m/s and ΔT_sub = 70 °C; 2) JSPM, JDPM and JUPM all increase the HTC due to more nucleation sites in the early boiling stage, the highly-efficient thin film evaporation in the middle boiling stage, and the enhanced liquid supply to the heating surface in the late boiling stage. Moreover, JSPM has a higher HTC than JDPM and JUPM due to the further enhanced liquid supply; 3) JUPM, JDPM and JSPM all reduce the pressure drop due to the suppression of reverse flow and violent vapor generation from local dry out. Although they have comparable pressure drop, JSPM yields a slightly lower value in the late boiling stage; 4) JSPM, JUPM and JDPM all have better thermal-hydraulic performance (i.e., higher COP). Moreover, JSPM achieves superior performance compared to JUPM and JDPM, with a maximum COP of 13197 when V_j = 1.5 m/s and ΔT_sub = 70 °C.

为了在芯片中实现超高热流密度耗散，提出了一种混合射流/梯度密度-针鳍-微通道的硅基散热器。具体而言，制备了混合射流/均匀针鳍微通道（JUPM，作为无梯度密度设计的控制案例）、混合射流/密集到稀疏针鳍微通道（JDPM）和混合射流/稀疏到密集针鳍微通道（JSPM）。通过数据采集系统与高速显微镜相机相结合，实验研究了JUPM、JDPM和JSPM中去离子水在射流速度（Vj = 1.5、2、2.5 m/s）和入口过冷（ΔTsub = 30、50、70°C）范围内的传热性能、沸腾流型、压降和性能系数（COP）。结果表明：1)JSPM、JDPM和JUPM均提高了受热面的临界热流密度（CHF），这是由于抑制了逆流和毛细管驱动的液体桥导致的液体供应增加。此外，由于下游存在更多的液体桥，JSPM比JDPM和JUPM进一步增加了CHF。特别是当Vj = 2.5 m/s， ΔTsub = 70℃时，JSPM的CHF最高，达到1464 W/cm2；2) JSPM、JDPM和JUPM均因沸腾前期成核位点较多、沸腾中期薄膜蒸发效率高、沸腾后期受热面供液量增加而提高了HTC。此外，JSPM比JDPM和JUPM有更高的HTC，这是由于液体供应进一步增加；3) JUPM、JDPM和JSPM均通过抑制逆流和局部干透产生的剧烈蒸汽而降低压降。虽然它们具有相当的压降，但JSPM在沸腾后期产生的压降略低；4) JSPM、JUPM和JDPM均具有较好的热工性能（COP较高）。JSPM在Vj = 1.5 m/s、ΔTsub = 70°C时的COP最大值为13197，性能优于JUPM和JDPM。

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引用次数: 0

3D pore-scale digital twin for assessing thermal effects on two-phase flow and relative permeability in Bentheimer sandstone 三维孔隙尺度数字孪生模型用于评估Bentheimer砂岩两相流和相对渗透率的热效应

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-28 DOI: 10.1016/j.ijheatmasstransfer.2026.128340

Farhad Mesbah, Javad Siavashi, Mohammad Sharifi

Rising energy demand necessitates efficient use of low-mobility oil resources through thermal methods. This study addresses a critical gap by numerically investigating the effect of heat transfer on multiphase flow at the pore scale, considering both macroscopic and microscopic perspectives simultaneously, focusing on relative permeability (

k_{r}

) and mechanisms of oil mobilization. Simulations were conducted using the finite volume method (FVM) and the volume of fluid (VOF) approach within OpenFOAM.

k_{r}

was evaluated via the unsteady-state technique, incorporating temperature-dependent fluid properties. Initially, the sensitivity of

k_{r}

to viscosity ratio (

M

) was examined at

M

values of 1, 10, and 50, revealing significant impacts on flow behavior. Subsequently, the effect of water-injection temperature (

T_{w i n j}

), ranging from 313 to 393 K, was assessed. Results indicate that increasing temperature enhances oil relative permeability (

k_{r o}

) while water relative permeability (

k_{r w}

) remains largely temperature-independent, except at curve endpoints. Endpoint

k_{r o}

and

k_{r w}

increased from 0.66 to 1.00 and 0.83 to 1.00, respectively, as the temperature rose. Elevated temperatures also reduced residual oil saturation (

S_{o r}

) from 0.225 to 0.109 by promoting water penetration into narrower pores and mobilizing trapped oil, leading to the occurrence of the oil ganglion phenomenon. Accordingly, with increasing temperature, oil clusters migrate more rapidly, leading to a reduction in oil volume by 12.4% and 28.9% at 363 K and 393 K, respectively. These findings underscore the crucial role of thermal processes in improving fluid displacement efficiency, highlighting their importance for sustainable subsurface resource management.

不断增长的能源需求要求通过热法有效利用低流动性的石油资源。本研究通过数值研究传热对孔隙尺度多相流的影响，同时考虑宏观和微观视角，关注相对渗透率（kr）和石油动员机制，解决了一个关键的空白。在OpenFOAM中采用有限体积法（FVM）和流体体积法（VOF）进行了模拟。Kr通过非稳态技术进行评估，结合了温度相关的流体特性。首先，在M值为1、10和50时，研究了kr对粘度比(M)的敏感性，揭示了对流动行为的显著影响。随后，评估了注水温度（Twinj）在313 ~ 393 K范围内的影响。结果表明，温度升高会提高油的相对渗透率（kro），而水的相对渗透率（krw）在很大程度上与温度无关，除了曲线端点。随着温度的升高，终点kro和krw分别从0.66增加到1.00和0.83增加到1.00。高温还通过促进水渗透到较窄的孔隙中并调动被困油，使残余油饱和度（Sor）从0.225降低到0.109，从而导致油神经节现象的发生。因此，随着温度的升高，油簇的迁移速度更快，导致油体积在363 K和393 K时分别减少12.4%和28.9%。这些发现强调了热过程在提高流体驱替效率方面的关键作用，强调了热过程对可持续地下资源管理的重要性。

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引用次数: 0

Identification of thermal conductivities for nonhomogeneous materials based on the hybrid machine learning model 基于混合机器学习模型的非均匀材料导热系数辨识

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-30 DOI: 10.1016/j.ijheatmasstransfer.2026.128446

Haolong Chen , Yuanlin Yi , Zhaotao Liu , Zhanli Liu , Huanlin Zhou

A hybrid machine learning model, combining the level set, the discrete cosine transform (DCT), with the convolutional neural network (CNN), is proposed for identifying thermal conductivities for nonhomogeneous materials in heat conduction problems without prior knowledge. The finite element method is used to analyze the heat conduction in nonhomogeneous materials. The level set approach can segment the temperature RGB image and avoid tracking the evolution process of the closed curve. The DCT is used to extract the main features and reduce dimensionality both in the temperature field and the thermal conductivity. The CNN is developed to establish the relationship between the input (main features of temperature field) and the output (main features of thermal conductivity). Finally, the unknown thermal conductivities of the nonhomogeneous material can be acquired by the inverse DCT. The impacts of varying main feature sizes, measurement errors, and training datasets on the outcomes are systematically analyzed to validate the proposed methodology. As the main feature size increases and measurement error decreases, the estimated results become more accurate. The study provides a robust method for reverse identification of thermal conductivity for nonhomogeneous materials, with potential applications in spanning real-time elastography and high-throughput non-destructive evaluation techniques.

提出了一种结合水平集、离散余弦变换（DCT）和卷积神经网络（CNN）的混合机器学习模型，用于在没有先验知识的情况下识别热传导问题中非均匀材料的导热系数。采用有限元法对非均匀材料的热传导进行了分析。水平集方法可以分割温度RGB图像，避免跟踪封闭曲线的演化过程。DCT用于提取温度场和导热系数的主要特征并进行降维。开发CNN是为了建立输入（温度场的主要特征）和输出（导热系数的主要特征）之间的关系。最后，非均匀材料的未知热导率可以通过反离散余弦变换得到。系统地分析了不同主要特征大小、测量误差和训练数据集对结果的影响，以验证所提出的方法。随着主特征尺寸的增大和测量误差的减小，估计结果越来越准确。该研究为非均匀材料的热导率反向识别提供了一种强大的方法，在跨越实时弹性成像和高通量无损评估技术方面具有潜在的应用前景。

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引用次数: 0

Functionally-graded drug delivery systems with binding reactions: Analytical and stochastic approaches for the fraction of drug released 结合反应的功能分级药物传递系统：药物释放部分的分析和随机方法

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-10 DOI: 10.1016/j.ijheatmasstransfer.2026.128455

Obi A. Carwood, Elliot J. Carr

Mathematical modelling and computer simulation are increasingly being used alongside experiments to help optimise and guide the design of drug delivery systems. Recent drug delivery research has (i) highlighted the advantages of drug delivery systems constructed using functionally-graded materials to achieve target release rates and desired dosage levels over time; and (ii) revealed how it is possible for drug to bind to the carrier material and become irreversibly immobilised within the system, reducing the amount of drug delivered. In this paper, we consider the effect of functionally-graded materials and binding reactions on drug release from common slab, cylinder and sphere devices. In particular, two key contributions are presented. First, we outline a deterministic-continuum approach that develops exact analytical expressions for calculating the total fraction of drug released from the device based on a partial differential equation model of the release process. Second, we develop a stochastic-discrete approach for calculating the fraction of drug released over time based on a random-walk model that captures the randomness of the release process and resulting variability in the total fraction of drug released. Both approaches are numerically validated and provide tools for exploring how the fraction of drug released depends on system parameters (e.g. diffusivity and reaction-rate functions induced by the functionally-graded material and binding reactions), insight which may be useful for designers of drug delivery systems.

数学建模和计算机模拟越来越多地与实验一起使用，以帮助优化和指导药物输送系统的设计。最近的药物递送研究(i)强调了使用功能分级材料构建的药物递送系统的优势，可以随着时间的推移达到目标释放率和所需剂量水平；并且（ii）揭示了药物如何可能与载体材料结合并在系统内不可逆地固定，从而减少了药物的递送量。在本文中，我们考虑了功能梯度材料和结合反应对药物在普通平板、圆柱形和球形装置中的释放的影响。特别提出了两个关键贡献。首先，我们概述了一种确定性连续体方法，该方法基于释放过程的偏微分方程模型，开发了精确的解析表达式，用于计算从设备释放的药物总分数。其次，我们开发了一种基于随机游走模型的随机离散方法，用于计算随时间释放的药物比例，该模型捕获了释放过程的随机性和由此产生的药物总释放比例的可变性。这两种方法都经过了数值验证，并为探索药物释放的比例如何依赖于系统参数（例如，由功能梯度材料和结合反应引起的扩散率和反应速率函数）提供了工具，这可能对药物输送系统的设计者有用。

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引用次数: 0

Adsorption kinetics of difluoromethane on biomass-derived activated carbon through experimental and modeling approaches 生物质活性炭对二氟甲烷的吸附动力学研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-04 DOI: 10.1016/j.ijheatmasstransfer.2026.128471

Huiyuan Bao , Md. Amirul Islam , Sixu Zhang , Yuetuo Lu , Bidyut Baran Saha

This study investigated the adsorption kinetics of difluoromethane (R32) on mangrove-derived activated carbon (MAC) over 30–90°C and 0–3000 kPa using a thermogravimetric (TGA) setup. To capture the transient uptake and investigate the equilibrium pressure effects on adsorption kinetics, a dual pseudo-first-order (dual-PFO) model was adopted, in which total uptake is expressed as the sum of two branches with distinct rate constants (

k_{1}

,

k_{2}

); their contributions to total uptake are characterized by the fractional capacity

α

. The model fitted all the experiments with high accuracy (average R² = 0.9976). Parameter analysis showed that

α

and

k_{1}

decrease as the equilibrium pressure increases, whereas

k_{2}

is nearly pressure-invariant. Applying the dual-PFO model to literature datasets (Maxsorb III/R32 and MAC/CO₂),

α, k_{1}

and

k_{2}

exhibited the same pressure dependence trend as MAC/R32. Comparison of fitted parameters across three working pairs together with pore-structure differences between MAC and Maxsorb III indicates a mesopore-associated fast branch and a micropore-controlled slow branch. Parameters (

α, k_{1}, k_{2}

) were regressed as functions of pressure and temperature, yielding a global correlation formula that reproduces representative curves with high accuracy. Embedding the correlation in a dynamic two-bed R32/MAC adsorption cooling model yielded a coefficient of performance (COP) of 0.173 and a cooling power (CP) of 1.47 kW under representative conditions (T_evap = 10°C, T_cond = 30°C, T_des = 75°C), suggesting that MAC/R32 is a promising working pair and that the dual-PFO kinetics can facilitate system-level performance evaluation under the examined conditions.

采用热重法（TGA）研究了在30-90°C和0-3000 kPa条件下，红树林活性炭（MAC）对二氟甲烷（R32）的吸附动力学。为了捕获瞬时吸收率并研究平衡压力对吸附动力学的影响，采用双伪一阶（dual- pfo）模型，其中总吸收率表示为具有不同速率常数（k1, k2）的两个分支的和；它们对总吸收量的贡献表现为分数容量α。模型拟合精度较高（平均R2 = 0.9976）。参数分析表明，α和k1随平衡压力的增大而减小，而k2几乎是压力不变的。将双pfo模型应用于文献数据集（Maxsorb III/R32和MAC/CO2）， α、k1和k2表现出与MAC/R32相同的压力依赖趋势。通过比较三个工作对的拟合参数以及MAC和Maxsorb III之间的孔隙结构差异，可以发现与介孔相关的快速分支和微孔控制的慢分支。将参数（α,k1,k2）回归为压力和温度的函数，得到一个全局相关公式，该公式可以高精度地再现具有代表性的曲线。在典型条件下（Tevap = 10°C, Tcond = 30°C, Tdes = 75°C）， R32/ R32吸附冷却模型的性能系数（COP）为0.173，冷却功率（CP）为1.47 kW，表明MAC/R32是一个有前途的工作对，双pfo动力学可以促进系统级性能评价。

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引用次数: 0

Multi-goal forced convection heat transfer control for cylinder under online and offline scenarios via deep reinforcement learning 基于深度强化学习的气缸在线和离线多目标强制对流换热控制

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-05 DOI: 10.1016/j.ijheatmasstransfer.2026.128468

Feitong Wang , Yumeng Tang , Jiexuan Hou , Yangwei Liu

Deep reinforcement learning (DRL)-based forced convection heat transfer control encounters challenges when facing complex control objectives and scenarios. This study focuses on a two-dimensional cylindrical heat source within a narrow cavity. First, DRL is applied to perform the energy-efficient cooling task with an energy penalty term incorporated into the reward. Results show that the continuous DRL algorithm achieves the best performance, with a comprehensive gain exceeding the baseline by 25.1%. To handle temperature control tasks with variable goals, a goal-oriented reinforcement learning (GoRL) framework is established. Results show that control accuracy decreases as the goal space expands, however, it can be improved by employing hindsight experience replay with a future method and designing the observation space such that the reward becomes a function of the observation. The GoRL framework achieves precise variable-goal temperature control across a broad continuous goal space of 20 K with a single training process, yielding a temperature variance of 0.1071 while consuming only 5% computational resources required by traditional DRL frameworks. Furthermore, considering scenarios where online DRL learning and interaction are restricted due to safety or cost constraints, a continuous goal-oriented conservative Q-learning (GoCQL) framework is proposed, aiming to rapidly accomplish variable-goal temperature control solely based on the randomized offline dataset. Results demonstrate that GoCQL agent exhibits excellent generalization ability, achieving a temperature variance of 0.1572. Moreover, the time consumption of offline learning is less than 1% of that of online learning under a complete training session, enabling fast acquisition of control strategies in scenarios where online interaction is impractical.

基于深度强化学习（Deep reinforcement learning， DRL）的强制对流换热控制在复杂的控制目标和控制场景下面临挑战。本文主要研究了窄腔内的二维圆柱形热源。首先，将DRL应用于节能冷却任务，并在奖励中加入能量惩罚项。结果表明，连续DRL算法性能最佳，综合增益比基线高出25.1%。为了处理具有可变目标的温度控制任务，建立了面向目标的强化学习（GoRL）框架。结果表明，控制精度随着目标空间的扩大而下降，但可以通过采用后见之明的经验回放方法和设计观察空间使奖励成为观察的函数来提高控制精度。GoRL框架通过单个训练过程在20 K的连续目标空间内实现精确的变目标温度控制，产生的温度方差为0.1071，而消耗的计算资源仅为传统DRL框架所需的5%。此外，考虑到在线DRL学习和交互受到安全或成本约束的情况，提出了一种连续面向目标的保守q -学习（GoCQL）框架，旨在仅基于随机化的离线数据集快速完成变目标温度控制。结果表明，GoCQL代理具有良好的泛化能力，实现了0.1572的温度方差。此外，在完整的训练课程下，离线学习的时间消耗不到在线学习的1%，可以在无法进行在线交互的情况下快速获取控制策略。

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引用次数: 0

A high-precision analytical model of transient thermal stresses of through-silicon vias in 3-D integrated circuits 三维集成电路硅通孔瞬态热应力的高精度解析模型

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-06 DOI: 10.1016/j.ijheatmasstransfer.2026.128356

Luhao Zhai, Junqin Zhang, Guangbao Shan, Xin Jin, Wenting Chen, Yintang Yang

In three-dimensional integrated circuits (3-D ICs), through-silicon vias (TSVs) are subject to significant thermal stress due to mismatches in the coefficients of thermal expansion (CTE) among constituent materials, which severely compromises device reliability. Grounded in thermoelastic theory, this paper presents a high-precision analytical model for predicting transient thermal stress in TSVs. First, an analytical solution for the transient temperature field within TSVs is derived using heat conduction theory in a cylindrical coordinate system. Subsequently, by incorporating the thermoelastic displacement potential and Love's displacement function, a closed-form analytical model for transient thermal stress is formulated. The model further accounts for axial third-kind thermal boundary conditions and incorporates temperature-dependent material properties to enhance physical realism. Validation against COMSOL multiphysics simulations demonstrates that the maximum relative error and maximum absolute error in the predicted transient temperature field remain below 1.2 % and 0.4 K, respectively, while the corresponding errors for von Mises stress are within 1.6 % and 0.8 MPa. Notably, the computational efficiency of the proposed model exceeds that of the finite element method (FEM) by approximately two orders of magnitude. Moreover, it exhibits strong adaptability across a wide range of material combinations and geometric configurations. We further employ the analytical model to investigate the effect of thermal stress on carrier mobility in TSVs and the stress interaction between adjacent TSVs. In comparison with classical 2-D Lamé solutions and 3-D Kane-Mindlin theory, the proposed model achieves superior accuracy without relying on empirical correction factors and effectively captures the spatial distribution of thermal stress in TSVs under transient thermal conditions. This study confirms that the developed analytical model offers exceptional accuracy and efficiency in characterizing transient thermal stress distributions in 3-D IC TSVs, thereby providing a robust and precise tool for thermomechanical reliability assessment and design optimization.

在三维集成电路（3-D ic）中，由于组成材料之间的热膨胀系数（CTE）不匹配，硅通孔（tsv）受到显著的热应力影响，这严重影响了器件的可靠性。本文以热弹性理论为基础，提出了一种高精度的热应力预测模型。首先，在柱面坐标系下，利用热传导理论，推导出了热传导理论下tsv内瞬态温度场的解析解。结合热弹性位移势和Love位移函数，建立了瞬态热应力的封闭解析模型。该模型进一步考虑了轴向第三类热边界条件，并结合了与温度相关的材料特性，以增强物理真实性。COMSOL多物理场模拟验证表明，预测瞬态温度场的最大相对误差和最大绝对误差分别在1.2%和0.4 K以下，而von Mises应力的相应误差在1.6%和0.8 MPa以内。值得注意的是，该模型的计算效率比有限元法（FEM）高出约两个数量级。此外，它在广泛的材料组合和几何结构中表现出很强的适应性。我们进一步利用分析模型研究了热应力对载流子迁移率的影响以及相邻tsv之间的应力相互作用。与经典的二维lam解和三维Kane-Mindlin理论相比，该模型在不依赖经验修正因子的情况下具有更高的精度，并能有效地捕捉瞬态热条件下tsv内热应力的空间分布。本研究证实，所建立的分析模型在表征三维集成电路tsv的瞬态热应力分布方面具有卓越的准确性和效率，从而为热机械可靠性评估和设计优化提供了一个强大而精确的工具。

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引用次数: 0

Design and fabrication of high-permeability plain-woven ceramic matrix composites: Experimental and numerical investigation on flow and heat transfer characteristics 高渗透陶瓷基复合材料的设计与制造：流动与传热特性的实验与数值研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-24 DOI: 10.1016/j.ijheatmasstransfer.2026.128399

Tao Ding , Shiyu Qian , Hua Zhou , Hainan Zhang , Xiaoxuan Chen , Weigang Ma

Ceramic matrix composites (CMCs), distinguished by their high-temperature resistance, low density, and high specific strength, are extensively employed in the hot-end components of aero-engines. The pores inside CMCs can serve as seepage channels for transpiration cooling. This study obtained the permeability and inertial coefficient of two-dimensional plain-woven (2DPW) CMCs by experiments and then established a parametric modeling method and pore-scale simulation methodology specifically for 2DPW, and the internal flow mechanism was analyzed. Firstly, an experimental investigation was conducted to explore the flow characteristics, and the permeability and inertial coefficients among different porous medium were compared. Second, the internal geometric structure of the material was captured using a micro-computed tomography scanning method, and a simplified parametric modeling method was developed. Third, a representative volume element was constructed for pore-scale internal flow simulations. Numerically predicted pressure drops versus flow rate characteristics were validated against experimental data. Finally, an analysis was conducted on the internal flow and heat transfer characteristics, and the flow resistance as well as the volumetric convective heat transfer coefficient were acquired. The results indicated that the complex pore structure induced by inter-layer misalignment gives rise to high fluid tortuosity, resulting in significant variations in the magnitude and direction of the flow velocity, which contribute to the high inertial resistance. For the coupled flow and heat transfer process, the numerical simulation results show that the staggered 2D plain woven structure forces the fluid to pass through the inter-layer pores when flowing through the woven meshes of different layers, which generates substantial flow resistance while enhancing the heat transfer performance. The high-velocity flow within the narrow inter-layer pores provides the basis for high heat transfer, and the dual heat sources are derived from both the high-temperature solid matrix and the high-temperature swirling flow in the inter-bundle pores. This study provided guidance for the establishment of 2DPW geometric models, the analysis of flow and heat transfer characteristics, and the gradient porosity design in transpiration cooling.

陶瓷基复合材料具有耐高温、低密度、高比强度等特点，在航空发动机热端部件中得到了广泛应用。cmc内部的孔隙可以作为蒸腾冷却的渗流通道。通过实验获得二维平面编织（2DPW） cmc的渗透率和惯性系数，建立了专门针对二维平面编织（2DPW） cmc的参数化建模方法和孔隙尺度模拟方法，并对其内部流动机理进行了分析。首先进行了流动特性实验研究，比较了不同多孔介质间的渗透率和惯性系数。其次，利用微计算机断层扫描方法捕获材料内部几何结构，并建立了简化的参数化建模方法；第三，构建具有代表性的孔隙尺度内部流动模拟体积元。通过实验数据验证了数值预测的压降与流量的关系。最后对其内部流动和换热特性进行了分析，得到了流动阻力和体积对流换热系数。结果表明：层间错位引起的复杂孔隙结构导致了流体的高挠度，导致流速大小和方向的显著变化，从而导致了高惯性阻力。对于流动与换热耦合过程，数值模拟结果表明，交错的二维平面编织结构迫使流体在流过不同层的编织网格时穿过层间孔隙，在增强传热性能的同时产生了较大的流动阻力。窄层间孔隙内的高速流动为高换热提供了基础，双热源来源于高温固体基质和束间孔隙内的高温旋流。该研究为2DPW几何模型的建立、流动传热特性的分析以及蒸腾冷却的梯度孔隙度设计提供了指导。

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引用次数: 0

Topology optimization of plate heat exchangers via geometry projection 基于几何投影的板式换热器拓扑优化

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-11 DOI: 10.1016/j.ijheatmasstransfer.2026.128486

Prabin Pradhananga , Navid Changizi , Zhiyuan Qu , André Benard , Patrick Kwon , Haseung Chung , Julián Norato

This study aims to advance the design of plate heat exchangers via a topology optimization framework. The design problem consists of determining the optimal layout and dimensions of the flow structure in the plates, which are herein modeled as offset bars. The geometry projection method is employed to map the geometric parameters that describe the bars onto a continuous pseudo-density field. As in density-based topology optimization techniques, this pseudo-density is used to perform the analysis through a suitable interpolation of material properties. A conjugate heat transfer analysis is performed to evaluate the performance of the heat exchanger. Taking advantage of the relatively small number of design parameters describing the flow structures, we employ an off-the-shelf solver and parallel computing to obtain design sensitivities using a finite difference approximation. The proposed method is applied to known benchmarks in topology optimization for fluids to verify its effectiveness. The method is subsequently applied to the design of a plate heat exchanger.

本研究旨在通过拓扑优化框架来推进板式换热器的设计。设计问题包括确定板内流动结构的最佳布局和尺寸，本文将板内流动结构建模为偏移杆。采用几何投影法将描述棒材的几何参数映射到连续的伪密度场上。与基于密度的拓扑优化技术一样，该伪密度用于通过适当的材料特性插值来执行分析。对换热器进行了共轭传热分析，以评价换热器的性能。利用描述流结构的设计参数相对较少的优势，我们使用现成的求解器和并行计算来使用有限差分近似获得设计灵敏度。将该方法应用于已知的流体拓扑优化基准，验证了其有效性。该方法随后应用于板式换热器的设计。

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引用次数: 0