Case Studies in Thermal Engineering最新文献_第6页

A unified immersed boundary method for conjugate heat transfer with stable interface temperature treatment 界面温度稳定处理共轭传热的统一浸入边界法

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107671

Chung-Gang Li

This study presents a unified immersed boundary method for simulating conjugate heat transfer (CHT) in systems with complex geometries and large contrasts in thermal conductivity. The method applies a compressible Navier-Stokes formulation across both fluid and solid regions, thereby eliminating the need for separate solvers or coupling schemes. A locally one-dimensional (LOD) interface model is proposed to compute interface temperatures using conductivity- and distance-weighted averaging, ensuring energy conservation and numerical stability at fluid–solid interfaces. The proposed framework is validated through natural convection and rotating flow benchmarks, showing good agreement with reference solutions and clear grid convergence behavior. In particular, the method remains stable and accurate for cases involving large thermal conductivity ratios (up to ks/kf = 50). The framework is further applied to a realistic rotating fan–heat sink configuration with different material conductivities, demonstrating its capability to handle complex geometries, moving boundaries, and strong thermal property contrasts. These results confirm that the proposed unified approach provides a robust and efficient solution for engineering-scale CHT problems and is well suited for high-performance computing environments.

本文提出了一种统一浸入边界法，用于模拟具有复杂几何形状和导热系数差异大的系统中的共轭传热。该方法适用于流体和固体区域的可压缩Navier-Stokes公式，从而消除了对单独求解器或耦合方案的需要。提出了一种局部一维（LOD）界面模型，利用电导率和距离加权平均计算界面温度，保证了流固界面的能量守恒和数值稳定性。通过自然对流和旋转流基准测试，验证了该框架与参考解的一致性和清晰的网格收敛行为。特别是，该方法在涉及大导热系数比（高达ks/kf = 50）的情况下保持稳定和准确。该框架进一步应用于具有不同材料导电性的现实旋转风扇散热器配置，展示了其处理复杂几何形状，移动边界和强烈热性能对比的能力。这些结果证实了所提出的统一方法为工程规模的CHT问题提供了一个鲁棒和有效的解决方案，并且非常适合高性能计算环境。

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引用次数: 0

Energy–Exergy and Entropy Generation Analysis of a PVT-TEG Module Using a Sinusoidal Channel Combined with Jet-Impingement Cooling 基于正弦通道结合射流冲击冷却的PVT-TEG模块能量-火用和熵产分析

IF 6.8 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107662

Hatem Gasmi, Khalil Hajlaoui, Ali M. Mohsen, As'ad Alizadeh, Mujtaba A. Flayyih, Mohamed Shaban, Walid Aich, Karim Kriaa

This study investigates the thermo-electrical performance and entropy generation of a hybrid PVT-TEG system cooled by a Jet Impingement Module (JIM) across four channel geometries and Re numbers (400-1600). The JIM system achieved superior thermal management, significantly reducing the average PV temperature by up to 3.4 K to a stable 305.3 K and lowering the thermal entropy generation by 15-25%. However, this enhancement came with a substantial energy penalty. The parasitic power required for pumping surged by orders of magnitude, reaching over 2 W, which drastically reduced the net electrical output. Consequently, the system's net electrical power was nearly halved (1.92-2.16 W with JIM vs. ∼3.95 W without JIM), and the electrical exergy efficiency reduced to 7.7-8.6% compared to 15.8-15.9% for the non-JIM configuration. Furthermore, while thermal irreversibilities were reduced, frictional entropy generation became dominant, soaring to values between 819 and 1074 W/K due to the intense fluid friction in the JIM cooler. The results demonstrate a critical trade-off, where the significant pumping power consumption and associated frictional losses ultimately outweigh the benefits of improved heat transfer, rendering the simple channel without JIM more effective for net energy production.

本研究研究了由射流撞击模块（JIM）冷却的混合PVT-TEG系统的热电性能和熵生成，该系统跨越四种通道几何形状和Re数（400-1600）。JIM系统实现了卓越的热管理，将PV平均温度降低了3.4 K，达到稳定的305.3 K，并将热熵产生降低了15-25%。然而，这种增强带来了大量的能量损失。泵送所需的寄生功率激增了几个数量级，达到2w以上，这大大降低了净电力输出。因此，系统的净电功率几乎减少了一半（使用JIM时为1.92-2.16 W，而不使用JIM时为3.95 W），电能效率降至7.7-8.6%，而非JIM配置时为15.8-15.9%。此外，当热不可逆性降低时，摩擦熵产生成为主导，由于JIM冷却器中强烈的流体摩擦，其值飙升至819至1074 W/K之间。结果表明了一个关键的权衡，其中显著的泵送功率消耗和相关的摩擦损失最终超过了改善传热的好处，使得没有JIM的简单通道更有效地产生净能量。

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引用次数: 0

Research on the heat storage and optimization of the heat transfer performance of a phase change heat storage heat exchanger based on flow heat transfer 基于流动换热的相变蓄热换热器蓄热及传热性能优化研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107658

Chuanhui Zhu , Xiaodong Dong , Yunlong Guan , Zhehao Lin , Wei Liu , Xifang Wang

Conserving energy, reducing emissions, and efficiently utilizing energy have become common global goals in the post-carbon era. Thermal storage technology can effectively solve the contradiction between thermal energy supply and demand in terms of time and intensity while avoiding energy waste, thus improving the efficiency of energy utilization. This study analyzes the influence of factors such as fin shape, thickness, quantity, and phase change material (PCM) filling thickness on the heat storage and transfer performance of a phase change heat storage heat exchanger (PC-HS-HE) through a combination of simulations and experimental methods. A geometric model was established that includes serpentine tubes and serrated fins, with paraffin wax used as the PCM filling the space between the tubes and fins. Through COMSOL simulation analysis, it was found that serrated fins could significantly enhance the heat exchange efficiency compared to flat fins by about 3.27 %. The height and quantity of fin teeth also have an impact on heat exchange performance, but too many fins can hinder external heat dissipation. The optimization of PCM filling thickness indicated that thinner PCM layers (70 mm) have a faster thermal response speed than thicker ones, but they also have a more limited thermal storage capacity. Based on the simulation results, an experimental platform was built to verify the thermal storage and release characteristics of the PC-HS-HE. The experiment shows that the heat exchanger exhibits significant improvement in heat exchange efficiency within the paraffin temperature range of 310–349 K. The study ultimately determined the optimal structure for the PC-HS-HE: five serrated fins with a tooth height of 1.6 mm and a PCM filling thickness of 70 mm. This structural design can achieve rapid PCM heating and stable heat release from thermal storage materials, making it suitable for scenarios requiring heating at a constant temperature.

节能减排、高效利用能源已成为后碳时代全球共同的目标。蓄热技术可以有效解决热能供需在时间和强度上的矛盾，同时避免能源浪费，从而提高能源利用效率。本研究通过模拟与实验相结合的方法，分析了翅片形状、厚度、数量、相变材料（PCM）填充厚度等因素对相变蓄热换热器（PC-HS-HE）蓄热传热性能的影响。建立了蛇形管和锯齿鳍的几何模型，以石蜡作为PCM填充管与鳍之间的空间。通过COMSOL模拟分析，发现锯齿形翅片比平面翅片能显著提高换热效率约3.27%。翅片齿的高度和数量对换热性能也有影响，但过多的翅片会阻碍外部散热。对PCM填充厚度的优化表明，较薄的PCM层（70 mm）的热响应速度快于较厚的PCM层，但其储热能力更有限。基于仿真结果，搭建了实验平台，验证了PC-HS-HE的储放热特性。实验表明，在310 ~ 349 K的石蜡温度范围内，换热器的换热效率有明显提高。研究最终确定PC-HS-HE的最佳结构为5片锯齿状翅片，齿高为1.6 mm， PCM填充厚度为70 mm。这种结构设计可以实现快速的PCM加热和稳定的储热材料热释放，使其适用于需要恒温加热的场景。

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引用次数: 0

Evolution of temperature field and optimization of insulation length in cold-region tunnels for conventional-speed railways 寒区高速铁路隧道温度场演化及保温长度优化

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107676

Zhengguo Zhu , Yunfei Ding , Hengxun Chen , Yongquan Zhu , Zhe Yang , Zihan Wang , Zhiming Han , Renyuan Wang

Conventional-speed railway tunnels in cold regions are frequently subjected to frost damage caused by extremely low temperatures, posing a significant threat to tunnel operation. Studies focused on determining the appropriate insulation length under conventional-speed train operations remain limited. In this study, a full-scale, three-dimensional dynamic numerical model was developed using CFD dynamic mesh technology. Pearson correlation coefficients were employed to quantitatively evaluate the influences of both static environmental conditions and train-induced dynamic factors on the tunnel temperature field. The temperature field distribution pattern and the effectiveness of insulation layers under conventional-speed train operations were investigated. The key findings are as follows: (1) Tunnel frost damage is primarily governed by the surrounding rock temperature and portal temperature. Train speed is positively correlated with the degree of frost damage, whereas the train length exhibits only minor and statistically insignificant effects. (2) A theoretical formula for calculating the thermal insulation length in cold-region conventional-speed railway tunnels was proposed, with key parameters of surrounding rock ground temperature, portal temperature, and train speed taken into account. The rationality and accuracy of the formula were validated using existing theoretical frameworks and real-world engineering cases. (3) With a surrounding rock ground temperature of 5 °C and portal temperatures of −10 °C, −15 °C, and −20 °C, extruded polystyrene (XPS) demonstrated the best overall performance. A five cm-thick adhered XPS insulation layer could reduce frost depth by 60 %–84 % and shorten the negative-temperature length by 81.6 %–100 %.

严寒地区的常规高速铁路隧道经常遭受极低温造成的冻害，对隧道运营构成重大威胁。研究集中在确定适当的绝缘长度在常规速度的列车运行仍然有限。本研究采用CFD动态网格技术建立了全尺寸的三维动态数值模型。采用Pearson相关系数定量评价静态环境条件和列车动力因素对隧道温度场的影响。研究了常温列车运行时保温层的温度场分布规律和保温层的有效性。研究结果表明：(1)隧道冻损主要受围岩温度和洞口温度的控制。列车速度与冻害程度呈正相关，而列车长度对冻害程度的影响较小，且统计上不显著。(2)提出了考虑围岩地温、道口温度、列车速度等关键参数的寒区常规高速铁路隧道保温长度的理论计算公式。利用现有理论框架和实际工程实例验证了公式的合理性和准确性。(3)当围岩地温为5℃，入口温度为- 10℃、- 15℃和- 20℃时，挤压聚苯乙烯（XPS）的综合性能最好。5 cm厚的粘接XPS保温层可使霜深减少60% ~ 84%，使负温长度缩短81.6% ~ 100%。

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引用次数: 0

Energy evolution and constitutive modeling of thermo-mechanical behavior in sandstone under real-time high temperature conditions 实时高温条件下砂岩热-力学行为的能量演化与本构模型

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107683

Yan Zhang , Yu Luo , Kai Meng , Xiangsheng Zheng , Minglang Zou , Haiquan Xiang

With the growing prevalence of underground engineering in high-temperature settings, understanding the thermo-mechanical behavior of rock masses has become essential for ensuring engineering rock mass stability. The focus of this study is the mechanical and energy characteristics of sandstone under real-time thermo-mechanical coupling with small temperature gradients (20–150 °C) and establishes a corresponding statistical damage constitutive model. Experimental results reveal a distinct temperature-dependent “grouping effect”: minor strength degradation occurs at 20–60 °C, whereas significant weakening is observed at 90–150 °C, attributed to a transition from evaporation-induced pore pressure to differential thermal expansion and microcracking. A novel axial stress ratio approach clearly delineates three energy evolution stages and a progressive decline in energy storage capacity with temperature, with all energy components exhibiting consistent grouping behavior and linear increase with confining pressure. The proposed constitutive model accurately captures stress-strain responses under thermo-mechanical coupling and reflects the material's brittle-ductile transition. It is concluded that sandstone behavior under coupled conditions is governed by the competition between thermal degradation and confining pressure strengthening. These findings provide theoretical and practical insights for rock engineering in thermal environments.

随着高温环境下地下工程的日益普及，了解岩体的热力学行为对保证工程岩体的稳定性至关重要。本文重点研究了砂岩在小温度梯度（20 ~ 150℃）下实时热-力耦合的力学和能量特征，并建立了相应的统计损伤本构模型。实验结果显示了明显的温度依赖“分组效应”：在20-60°C时，强度会发生轻微的退化，而在90-150°C时，由于从蒸发诱导的孔隙压力到差热膨胀和微开裂的转变，强度会显著减弱。一种新颖的轴向应力比方法清晰地描述了能量演化的三个阶段和能量储存容量随温度的逐渐下降，所有能量成分都表现出一致的分组行为，并随围压线性增加。提出的本构模型准确地反映了热-力耦合作用下的应力-应变响应，反映了材料的脆性-韧性转变。结果表明，在耦合条件下，砂岩的行为受热降解和围压强化的竞争支配。这些发现为热环境下的岩石工程提供了理论和实践见解。

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引用次数: 0

Study on the generation law of products and economy of oxygen-deficient combustion 贫氧燃烧的生成物生成规律及经济性研究

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107664

Hongtao Li , Jiajia Song , Han Li , Qingsong Song , Yunguang Ji , Yonggang Sheng

In response to the optimization requirements of low nitrogen combustion in gas heating furnaces, this study proposes a collaborative control method based on under oxygen combustion, which actively controls the excess air coefficient α (0.92–1.08) to balance fuel utilization and pollutant treatment costs. Through a combination of numerical simulation (with pure CH₄) and experimental verification (with a typical Chinese pipeline natural gas, predominantly CH₄ ≥ 95%), this study analyzes the generation laws and economic characteristics of combustion products under oxygen-deficient conditions. It was found that a decrease in alpha leads to incomplete combustion of fuel, which reduces furnace thermal efficiency but significantly alters the pathway of pollutant generation. When α < 0.94, the concentration of soot and CO increases significantly, creating a strong reducing atmosphere and inhibiting NO_x generation. By quantifying the game relationship between fuel cost increment and NO_x end treatment cost (ammonia injection cost, equipment investment), it was found that when α = 0.94–0.96, NO_x emissions are relatively low, meeting environmental requirements. Moreover, due to the chain like inhibitory effect of reducing substances on NO_x, the consumption of denitrification agents can be reduced. The innovation of this study lies in revealing the inherent logic of “replacing treatment costs with fuel loss” in oxygen deficient combustion, providing theoretical and practical support for industrial furnaces (especially those using high-methane natural gas) to choose a composite strategy of “moderate oxygen deficiency

+

end reduction” under environmental constraints.

针对燃气加热炉低氮燃烧的优化要求，本研究提出了一种基于低氧燃烧的协同控制方法，主动控制过量空气系数α(0.92-1.08)，平衡燃料利用率和污染物处理成本。本研究通过数值模拟（纯CH4）和实验验证（以中国典型管道天然气为主，CH4≥95%）相结合，分析了缺氧条件下燃烧产物的生成规律和经济性特征。研究发现，α的降低会导致燃料的不完全燃烧，从而降低炉膛热效率，但会显著改变污染物的生成途径。当α <； 0.94时，烟尘和CO浓度显著增加，形成了强还原气氛，抑制了NOx的生成。通过量化燃料成本增量与NOx末端处理成本（注氨成本、设备投资）之间的博弈关系，发现当α = 0.94-0.96时，NOx排放量相对较低，满足环保要求。此外，由于还原性物质对NOx具有链式抑制作用，可以减少脱硝剂的用量。本研究的创新之处在于揭示了缺氧燃烧“以燃料损失替代处理成本”的内在逻辑，为工业炉（特别是使用高甲烷天然气的工业炉）在环境约束下选择“适度缺氧+端部还原”的复合策略提供了理论和实践支持。

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引用次数: 0

Experimental investigation of methanol–biodiesel blend at high altitude: kinetic and performance characterization 高空甲醇-生物柴油混合燃料的实验研究：动力学和性能表征

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-08 DOI: 10.1016/j.csite.2026.107669

Huaping Xu, Shenghao Yu

This study investigates the combustion and emission characteristics of a methanol–biodiesel blend (BM20) under high-altitude conditions. A detailed reaction mechanism for methanol–biodiesel blends was developed for kinetic analysis. The results indicate that methanol addition at temperatures above 1000 K generates substantial quantities of OH radicals, while reducing the molar concentrations of acetylene (C₂H₂) and ethylene (C₂H₄)—key precursors of polycyclic aromatic hydrocarbons (PAHs). Experimental data further demonstrate that methanol can significantly mitigate the adverse effects of high-altitude intake hypoxia. Compared with diesel and biodiesel, BM20 shows superior performance. The brake thermal efficiency (BTE) of BM20 increases by up to 2.5 %. At medium–high loads, the power output rises by a maximum of 3.8 %, while the exhaust gas temperature (EGT) decreases by up to 12.4 %. NOx emissions decline by a maximum of 3.6 %, and low exhaust smoke levels are maintained under all load conditions, with peak reductions reaching 83.2 %. Notably, at higher load, both NOx and smoke emissions decrease simultaneously. These findings suggest that the distinctive combustion chemistry of methanol can facilitate cleaner and more efficient engine operation in oxygen-deficient environments.

本研究研究了一种甲醇-生物柴油混合物（BM20）在高海拔条件下的燃烧和排放特性。对甲醇-生物柴油共混反应机理进行了详细的动力学分析。结果表明，在1000 K以上的温度下，甲醇的加入产生了大量OH自由基，同时降低了多环芳烃（PAHs）的关键前体乙炔（C2H2）和乙烯（C2H4）的摩尔浓度。实验数据进一步证明，甲醇可以显著缓解高原摄入性缺氧的不良反应。与柴油和生物柴油相比，BM20表现出优越的性能。BM20的制动热效率（BTE）提高了2.5%。在中高负荷时，输出功率最高可提高3.8%，而废气温度（EGT）最高可降低12.4%。氮氧化物排放量最多减少3.6%，在所有负载条件下都保持低废气水平，峰值减少量达到83.2%。值得注意的是，在高负荷下，氮氧化物和烟雾排放量同时减少。这些发现表明，甲醇独特的燃烧化学性质可以促进发动机在缺氧环境中更清洁、更高效地运行。

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引用次数: 0

Heptane slick pool fires on water with inserted high-temperature heat pipes 插入高温热管的庚烷浮油池火灾在水中燃烧行为及传热途径分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-07 DOI: 10.1016/j.csite.2026.107673

Li Chang , Baisheng Nie , Yi Wei

The coupled heat transfer and combustion dynamics of floating fuel slicks play a critical role in governing flame behavior and burning characteristics. This study investigates the use of vertically inserted high-temperature heat pipes (HTHPs) at the burning surface of a 10 mm thick floating n-heptane slick. HTHPs (150 mm length, 30 mm diameter) with liquid metal working fluid are investigated under varying number (

N

= 1, 2, 3) and immersion depths (

h_{i m}

= 5–20 mm). Experimental analysis quantifies the dominant thermal pathways, including radiation, nucleate boiling, and conduction at key interfaces of the pool surface, the HTHP immersed wall, and the fuel/water interface. Flame height increases with the number of HTHPs but decreases with greater immersion depth, peaking at 90 cm for

N

= 3 at

h_{i m}

= 5 mm, which is a 44.3 % rise over baseline. The HTHP evaporator reaches isothermal temperatures of 400–550 °C, enabling effective vapor transport, while the bottom immersed section remains below the vapor flow transition temperature (181 °C) when immersed at 5–10 mm. Radiative heat fluxes from both the flame and the HTHP wall increase with

N

while nucleate boiling is enhanced by increasing the heat pipe wall exposure. An energy-based mass loss model efficiently captures experimental trends and reflects dynamic burning configurations. These findings demonstrate that phase change-driven heat transfer devices can modify the thermal feedback in n-heptane slick burning, providing mechanistic insights into heptane slick pool fire combustion with thermally conductive devices.

浮油的传热和燃烧耦合动力学对控制火焰行为和燃烧特性起着至关重要的作用。本研究研究了垂直插入高温热管（HTHPs）在10mm厚浮动正庚烷浮油燃烧表面的使用。研究了含液态金属工液的高温高压泵（150 mm长，30 mm直径）在不同浸没次数（= 1,2,3）和浸没深度（= 5-20 mm）下的性能。实验分析量化了主要的热途径，包括在池表面、高温高压浸入壁和燃料/水界面的关键界面的辐射、核沸腾和传导。火焰高度随着HTHPs数量的增加而增加，但随着浸泡深度的增加而降低，在= 3 at = 5 mm时火焰高度达到90 cm，比基线上升44.3%。高温高压蒸发器达到400-550℃的等温温度，能够有效地进行蒸汽输送，而底部浸入段在浸入5-10 mm时仍低于蒸汽流动转变温度（181℃）。火焰和高温高压壁的辐射热流随热管壁暴露量的增加而增加，而核沸腾随着热管壁暴露量的增加而增强。基于能量的质量损失模型有效地捕获了实验趋势并反映了动态燃烧构型。这些研究结果表明，相变驱动的传热装置可以改变正庚烷光滑油燃烧过程中的热反馈，为导热装置对正庚烷光滑油池燃烧的机理提供了新的认识。

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引用次数: 0

Categorization of fire load density based on the fire hazard classification of warehouse commodities 基于仓库商品火灾危险性分类的火灾负荷密度划分

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-07 DOI: 10.1016/j.csite.2026.107666

Ho-Sik Han, Cheol-Hong Hwang

Warehouse fires pose a significant threat due to rapid fire growth and high fire loads, often resulting in substantial loss of life and property. Accurately assessing the heat release characteristics of stored commodities is essential for developing effective fire protection strategies in warehouse environments. However, the considerable variability in commodity types, packaging conditions, rack configurations, and ventilation complicates the quantitative assessment of fire hazards based solely on the heat release rate (HRR). As an alternative, this study introduces a method for categorizing fire load density (FLD) based on commodity classification. A total of 338 data points for heat of combustion (HOC) and 613 bulk density measurements of packaged products were collected and analyzed. Statistically representative values of HOC and bulk density were derived for each commodity class using gamma distribution functions (GDFs). These values were then combined to calculate the heat release per unit area (HRPUA), which was used to quantify the FLD. The analysis revealed a clear upward trend in FLD with increasing commodity class, confirming the feasibility of class-based hazard differentiation. This approach offers a quantitative alternative to conventional qualitative assessments and provides a statistically grounded framework for evaluating fire hazards in warehouses, ultimately contributing to improved fire safety.

仓库火灾由于火势增长快、火灾负荷大，造成重大的生命财产损失。准确评估储存商品的热释放特性对于在仓库环境中制定有效的防火策略至关重要。然而，商品类型、包装条件、货架配置和通风的相当大的可变性使仅基于热释放率（HRR）的火灾危险定量评估复杂化。作为替代方案，本研究引入了一种基于商品分类的火灾负荷密度（FLD）分类方法。共收集和分析了338个燃烧热（HOC）数据点和613个包装产品的容重测量值。利用伽马分布函数（GDFs）推导出每个商品类别的HOC和容重的统计代表性值。然后将这些值结合起来计算单位面积放热（HRPUA），用于量化FLD。分析显示，随着商品类别的增加，FLD呈明显上升趋势，证实了基于类别的危险区分的可行性。这种方法为传统的定性评估提供了一种定量的替代方法，并为评估仓库的火灾危险提供了统计基础框架，最终有助于改善消防安全。

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引用次数: 0

Design optimization of a circular enclosure with flexible fins: Fluid-Structure interaction and heat transfer analysis using rotating frame modeling 柔性翅片圆形壳体的优化设计：基于旋转框架模型的流固耦合与传热分析

IF 6.4 2区工程技术 Q1 THERMODYNAMICS

Case Studies in Thermal Engineering

Pub Date : 2026-01-07 DOI: 10.1016/j.csite.2026.107668

Ali Qassim Abd Al-Hassan , Muneer A. Ismael , Mohammad Ghalambaz , Ali Chamkha , Mohamed Bechir Ben Hamida

This study optimizes heat transfer in a circular vessel containing cold and hot cylinders, a rotating frame, and flexible baffles designed to enhance thermal exchange. Optimized design of such topics improves the performance of heat exchangers. The investigation analyzes the impact of rotational speeds (ω∗ = 10–400), distances of the cylinders from the frame axis (e∗ = 0.32–0.43), and Rayleigh number (Ra = 10³–10⁵) on the heat transfer. Time-dependent equations are discretized and solved using the finite element method with rotating meshes. The Nelder-Mead optimization method was utilized to identify the optimal conditions that enhance the system's thermal stability and heat exchange efficiency. This approach establishes a foundation for improved thermal designs for applications requiring high dynamic thermal responsiveness. The results indicated that the maximum heat exchanges were obtained at e∗ = 0.32378 and ω∗ = 366.48 for Ra = 10³, and at e∗ = 0.32 and ω∗ = 379.43 for Ra = 10⁵. The Nusselt numbers for these conditions were 5.32 and 7.7, respectively. Therefore, to achieve optimal heat transfer, the operating conditions, such as the frame's angular speed and the cylinder's distance, should be optimized for each Rayleigh number.

本研究优化了一个圆形容器中的传热，该容器包含冷、热圆柱体、旋转框架和旨在增强热交换的柔性挡板。这些课题的优化设计提高了换热器的性能。研究分析了转速（ω∗= 10-400）、气缸与机架轴的距离（e∗= 0.32-0.43）和瑞利数（Ra = 103-105）对传热的影响。将时变方程离散化，采用旋转网格有限元法求解。利用Nelder-Mead优化方法确定了提高系统热稳定性和热交换效率的最佳条件。这种方法为需要高动态热响应性的应用的改进热设计奠定了基础。结果表明：当Ra = 103时，在e∗= 0.32378和ω∗= 366.48处换热最大；当Ra = 105时，在e∗= 0.32和ω∗= 379.43处换热最大。这两个条件下的努塞尔数分别为5.32和7.7。因此，为了实现最优的换热，需要对每个瑞利数下的机架角速度和气缸距离等工况进行优化。

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引用次数: 0