International Communications in Heat and Mass Transfer最新文献_第10页

The influence of discharge atmosphere on energy transport and thermal-fluid field synergy characteristics of long arc 放电大气对长电弧能量输运及热流场协同特性的影响

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-21 DOI: 10.1016/j.icheatmasstransfer.2026.110577

Xuan-Kai Zhang , Jin-Huan Pu , Lin Guo , Xiao-Min You , Mu Du

As the primary energy source, the long arc (LA) governs the physical fields and energy transfer in electric arc furnace (EAF). Studying the interaction mechanisms and influence laws among multiple physical fields in LAs is crucial for energy efficiency (η), yet such research remains limited, contributing to LA's status as a typical low-efficiency system. This study investigates how discharge atmosphere affects LA behavior using a magnetohydrodynamic-based electro-thermal-fluid coupling model. Distributions of electromagnetic, temperature, and flow fields under air and nitrogen (N₂) are analyzed. Results show that both arcs exhibit bell-shaped profiles, with N₂ enhancing plasma convergence near the axis due to lower electrical conductivity, leading to reduced anode receiving area and elevated axial temperatures. Improved synergy between thermal and flow fields in N₂ enhances convective heat transfer. Arc current (I) significantly impacts power and efficiency without altering flow distribution. Arc length (L) further affects energy distribution, enhancing power but reducing η. N₂ LAs are more sensitive to L and outperform air under extended conditions. Multiple regression models linking anode electric and heat flux densities to I, L, and radius achieve deviations within ±10%. The results highlight the importance of “ordered heat transfer”, which offering insights for optimized EAF control.

长弧作为电弧炉的主要能量源，控制着电弧炉的物理场和能量传递。研究多物理场之间的相互作用机制和影响规律对于提高激光激光器的能量效率（η）至关重要，但这方面的研究仍然有限，导致激光激光器处于典型的低效率体系的地位。本研究利用基于磁流体力学的电热-流体耦合模型研究了放电大气对LA行为的影响。分析了空气和氮气作用下的电磁场、温度场和流场分布。结果表明，两种电弧均呈钟形分布，N2由于电导率较低而增强了等离子体在轴线附近的收敛，导致阳极接收面积减小，轴向温度升高。N2中热流场的协同作用增强了对流换热。电弧电流(I)在不改变电流分布的情况下显著影响功率和效率。弧长(L)进一步影响能量分布，提高了功率，但降低了η。N2 LAs对L更敏感，在延长条件下优于空气。将阳极电通量和热流密度与I、L和半径联系起来的多重回归模型的偏差在±10%以内。结果强调了“有序传热”的重要性，为优化电炉控制提供了见解。

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引用次数: 0

Experimental investigation of a two-phase flow dynamic thermal management system for airborne pulsed lasers 机载脉冲激光器两相流动态热管理系统的实验研究

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-21 DOI: 10.1016/j.icheatmasstransfer.2026.110610

Yang Jiang , Jun Li , Kaijie Yang , Yixuan Liu , Erlin Meng , Yujie Huang

Airborne pulsed lasers are of great value in many aspects of modern times. The transient thermal shock and frequent temperature fluctuations generated by the high-power lasers used in their core components during pulsing can significantly impact the system's operational efficiency and stability. This study combines phase change material (PCM) thermal storage technology with pump-driven two-phase cooling to design and construct a high-heat-flux thermal management system for airborne pulsed lasers with adaptive flow control under dynamic conditions. Experimental analysis verified that the passive adaptive flow control method effectively matches the circulating flow rate to the system's operating conditions under dynamic heat loads. Furthermore, the PCM effectively buffers the heat accumulation generated by the laser's frequent pulsing, reducing the system's peak temperature by 2.7 °C under the same conditions. Furthermore, experiments show that the laser's operating power directly affects the temperature rise of the pump source, and determining the optimal operating power significantly improves the laser's sustained pulse stability. The duty cycle plays a crucial role in determining whether the laser can achieve thermal equilibrium. Excessive duty cycles exacerbate heat accumulation, while too low a duty cycle leads to excessive cooling, impacting subsequent operational efficiency. In the experiments, a duty cycle of 1:10 maintained stable operation within the initial cycle. For different initial operating temperatures, the initial temperature only affects the rate at which the system reaches equilibrium. Selecting an appropriate starting temperature can achieve thermal equilibrium of the pulse process more quickly.

机载脉冲激光器在现代的许多方面都具有重要的价值。核心器件中使用的大功率激光器在脉冲过程中产生的瞬态热冲击和频繁的温度波动会严重影响系统的运行效率和稳定性。本研究将相变材料（PCM）蓄热技术与泵驱动两相冷却技术相结合，设计并构建了动态条件下具有自适应流动控制的机载脉冲激光器高热流通量热管理系统。实验分析验证了被动自适应流量控制方法在动态热负荷下能有效地将循环流量与系统运行工况相匹配。此外，PCM有效地缓冲了激光频繁脉冲产生的热量积累，在相同条件下将系统峰值温度降低了2.7°C。此外，实验表明，激光器的工作功率直接影响泵浦源的温升，确定最佳工作功率可以显著提高激光器的持续脉冲稳定性。占空比对激光器能否达到热平衡起着至关重要的作用。过高的占空比会加剧热量积累，而过低的占空比会导致过度冷却，影响后续的运行效率。在实验中，以1:10的占空比保持了初始周期内的稳定运行。对于不同的初始工作温度，初始温度只影响系统达到平衡的速率。选择合适的启动温度可以更快地实现脉冲过程的热平衡。

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引用次数: 0

Flow and heat transfer characteristics of a novel m-shaped corrugated fin-and-tube heat exchanger with curved vortex generators 带有弯曲涡发生器的新型m型波纹翅片管换热器的流动和换热特性

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-20 DOI: 10.1016/j.icheatmasstransfer.2026.110567

XianJun Chang , Xiang Wu , AiLing He , Lin Chen , Feng Ding , KeWei Song

Corrugated fins are widely used in heat exchangers, and the performance optimization of corrugated fins has attracted significant attention. To enhance the heat transfer capacity of conventional corrugated fins, the present study proposes a novel m-shaped corrugated fin with compact corrugation arrangements that significantly intensify fluid disturbance. Integrating curved vortex generators, a proven method for enhancing convective heat transfer in fin-and-tube heat exchangers, into the m-shaped corrugated fin further optimizes thermo-hydraulic performance. The present investigation employs numerical simulation to compare the flow and heat transfer characteristics of different fin channels. The results show that, compared with the plain fin channel, the m-shaped corrugated fin channel with curved vortex generators enhances the secondary flow intensity by 33.44%–54.56%, the vorticity intensity in y-direction by 26.65%–29.24%, and the vorticity intensity in z-direction by 14.56%–18.09%. The m-shaped corrugated fin channel with curved vortex generators increases Nu by 72.81%–76.03% and achieves a maximum thermal performance factor of 1.38. To facilitate the engineering practice, correlations for Nu, f, and JF are fitted with Re. Furthermore, the analysis of contribution rate of vorticity intensity in different directions provides the theoretical foundation for heat exchanger design.

波纹翅片在换热器中得到了广泛的应用，波纹翅片的性能优化备受关注。为了提高传统波纹翅片的换热能力，本研究提出了一种新型的m型波纹翅片，其紧凑的波纹布置显著增强了流体扰动。将弯曲涡发生器集成到m形波纹翅片中，进一步优化了热工性能，这是一种在翅片-管式换热器中增强对流换热的行之有效的方法。本研究采用数值模拟的方法比较了不同翅片通道的流动和换热特性。结果表明：与平面翅片通道相比，带弯曲涡发生器的m型波纹翅片通道二次流强度提高33.44% ~ 54.56%，y方向涡度强度提高26.65% ~ 29.24%，z方向涡度强度提高14.56% ~ 18.09%；带弯曲涡发生器的m型波纹翅片通道使Nu增加72.81% ~ 76.03%，热性能因子达到最大1.38。为便于工程实际，将Nu、f、JF的相关关系用Re拟合，分析不同方向涡度强度的贡献率，为换热器设计提供理论依据。

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引用次数: 0

Enhanced boiling heat transfer and flow dynamics in loop thermosyphons with optimized rib-structured flat plate evaporators for IGBT thermal management 优化肋结构平板蒸发器用于IGBT热管理，增强了循环热虹吸管的沸腾传热和流动动力学

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-20 DOI: 10.1016/j.icheatmasstransfer.2026.110580

Hengxuan Xu , Xiangji Guo , Shaowei Yang , Bo Zhang , Binbin Wang

Loop thermosyphons provide a passive, high-efficiency cooling solution for high-power electronics. This study investigates the thermal-hydraulic performance of a vertically oriented flat plate evaporator designed for IGBT thermal management. We experimentally evaluated a smooth plate and three ribbed configurations under steady-state loads (100–900 W) and transient step changes. Results indicate that internal ribs significantly enhance boiling dynamics, reducing substrate temperatures by over 10 °C and improving thermal uniformity by nearly 50% under high heat fluxes compared to smooth plates. The medium-density ribbed plate (RP₂) achieved the lowest system thermal resistance by balancing nucleation enhancement with flow resistance. Conversely, while high-density ribs (RP₃) induced higher flow resistance during steady operation, they exhibited superior thermal stability during rapid load transients due to increased thermal inertia and nucleation area. The study reveals that optimized rib structures effectively delay the onset of dry-out and modulate two-phase flow regimes. These findings offer critical design criteria for balancing steady-state efficiency and transient stability in confined evaporator geometries.

环路热虹吸管为大功率电子设备提供了一种被动、高效的冷却解决方案。本文研究了用于IGBT热管理的垂直定向平板蒸发器的热工性能。我们在稳态载荷（100-900 W）和瞬态阶跃变化下实验评估了光滑板和三种肋结构。结果表明，与光滑板相比，在高热流密度下，内肋显著增强了沸腾动力学，使衬底温度降低了10°C以上，热均匀性提高了近50%。中密度肋板（RP2）通过平衡成核增强和流动阻力获得了最低的系统热阻。相反，虽然高密度肋（RP3）在稳定运行时产生更高的流动阻力，但由于热惯性和成核面积的增加，它们在快速负载瞬态时表现出优异的热稳定性。研究表明，优化后的肋结构可以有效地延缓干燥的发生并调节两相流型。这些发现为平衡密闭蒸发器的稳态效率和瞬态稳定性提供了关键的设计标准。

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引用次数: 0

Formation and evolution of pore ice in saturated soil with consideration of freezing point 考虑冰点的饱和土孔隙冰的形成与演化

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-20 DOI: 10.1016/j.icheatmasstransfer.2025.110286

Zongwei Gan, Zheng Wang, Yaning Zhang, Wenke Zhao, Bingxi Li

The distribution and evolution of pore ice are essential for the thermal-hydro-mechanical properties of frozen soil. This study proposed a lattice Boltzmann model to explore pore ice formation and evolution. The particle random distribution method was used to generate complex soil structures, and the generalized Clapeyron equation and pre-melting theory were used to calculate the freezing temperature distribution for capillary and bound water. The model incorporated the effects of particle size distribution and pore structure on freezing behavior, providing a novel approach for simulating the ice-water phase transition in frozen soil. The simulation results were validated against experimental data, with squared correlation coefficients of 0.961–0.946 for sand and silt loam in homogeneous freezing. For one-dimensional freezing, the coefficients were 0.87, 0.94, 0.90, and 0.84 at temperature boundary conditions of ‐2, ‐3, ‐4, and ‐5 °C, respectively. The homogeneous freezing process consisted of three stages: supercooling, rapid freezing, and slow freezing, with early stages influenced by pore structure and later stages governed by particle surface adsorption forces. The results indicate that the model effectively captured the mesoscopic characteristics of pore ice formation and evolution in soil, revealing the fundamental interaction mechanisms.

孔隙冰的分布与演化对冻土的热-水-力学性质至关重要。本研究提出了一种晶格玻尔兹曼模型来研究孔隙冰的形成和演化。采用颗粒随机分布法生成复杂土壤结构，采用广义Clapeyron方程和预融理论计算毛细水和束缚水的冻结温度分布。该模型考虑了粒径分布和孔隙结构对冻结行为的影响，为模拟冻土中冰-水相变提供了一种新的方法。模拟结果与试验数据吻合较好，均质冻结条件下砂粉壤土的相关系数均为0.961 ~ 0.946。对于一维冻结，在‐2、‐3、‐4和‐5℃温度边界条件下，系数分别为0.87、0.94、0.90和0.84。均匀冻结过程包括过冷、快速冻结和慢速冻结三个阶段，前期受孔隙结构影响，后期受颗粒表面吸附力影响。结果表明，该模型有效地捕捉了土壤孔隙冰形成与演化的细观特征，揭示了孔隙冰形成与演化的基本相互作用机制。

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引用次数: 0

Revealing the orientation threshold and optimum contact surface in flame formation, thermal processes, and combustion behaviour of moisturized solid fuel 揭示了湿润固体燃料在火焰形成、热过程和燃烧行为中的取向阈值和最佳接触面

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-20 DOI: 10.1016/j.icheatmasstransfer.2026.110582

Ali Edalati-nejad , Sara McAllister , Maryam Ghodrat , Jason J. Sharples

The ignition of small fuel elements plays a crucial role in fire propagation. These fine fuels are often the first to ignite and serve as a bridge for fire spread to larger scenarios. The moisture content of these fuels significantly affects their flammability and thermal behaviour. In this study, the effect of fuel moisture content (FMC) and orientation on the drying, pyrolysis, ignition, and thermal processes of a cellulose solid fuel is investigated through a series of numerical simulations. In addition, experimental ignition-time measurements were conducted at the U.S. Forest Service Missoula Fire Sciences Laboratory to provide an independent assessment of model performance. The simulations represent a leaf-scale fuel element allowed to heat up and ignite in a hot upwards-directed (convective) airflow. The leaf is considered in three different orientations of vertical, horizontal, and inclined at a 45° angle, and with five different FMC values between 4% and 63%. The simulations are conducted with FireFOAM, using Large Eddy Simulation (LES). Simulation results are validated against available experimental measurements, using the time evolution of the fuel mass loss. The results indicate the inclined orientation has the highest temperature increase among the three orientations, suggesting a critical angle exists for optimal convective heat transfer. Furthermore, the inclined orientation exhibited the highest drying and pyrolysis rates. This suggests that the angle between the airflow direction and the leaf surface normal critically influences the boundary layer development around the leaf.

小型燃料元件的点火对火灾的传播起着至关重要的作用。这些优良的燃料通常是首先点燃的，并作为火灾蔓延到更大场景的桥梁。这些燃料的水分含量显著影响其可燃性和热性能。本研究通过一系列数值模拟研究了燃料含水率（FMC）和取向对纤维素固体燃料干燥、热解、点火和热过程的影响。此外，在美国林务局米苏拉火灾科学实验室进行了实验点火时间测量，以提供对模型性能的独立评估。模拟模拟了一个叶片级的燃料元件，允许其在热的向上定向（对流）气流中加热并点燃。叶片在垂直、水平和倾斜45°的三种不同方向上被考虑，并且在4%到63%之间具有五种不同的FMC值。利用FireFOAM软件和大涡模拟软件（LES）进行了数值模拟。利用燃料质量损失随时间的变化规律，对模拟结果进行了验证。结果表明，三种取向中，倾斜取向的升温幅度最大，表明存在最佳对流换热的临界角。此外，倾斜方向表现出最高的干燥和热解速率。这表明气流方向与叶片表面法向之间的夹角对叶片周围边界层的发育有重要影响。

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引用次数: 0

Comparative thermo-structural analysis of annular cascade thermoelectric generator configurations for enhanced thermal reliability 提高热可靠性的环形叶栅热电发电机结构的热结构对比分析

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-20 DOI: 10.1016/j.icheatmasstransfer.2026.110543

Mutabe Aljaghtham

A mult-stage module is used to improve the temperature distribution in annular thermoelectric generators (ATEGs) in round-shaped applications. This study investigates the performance of unileg cascade ATEGs and compares it with that of unicouple cascade ATEGs for the first time.

The thermoelectric (TE) power and thermal stress of two- and three-stage configurations are analyzed using three-dimensional finite-element simulations. In a two-stage model, Half-Heusler and skutterudite are used as thermoelectric materials at the top and bottom stages, respectively. In a three-stage system, bismuth telluride is inserted at the bottom stage, below the Half-Heusler and skutterudite stages. The results reveal that the two-stage unicouple and unileg cascade ATEGs generate TE powers of 0.25 W and 0.29 W, respectively. In comparison, the three-stage unicouple and unileg systems produce 0.41 W and 0.46 W. The unileg multi-stage model outperforms unicouple cascade models by selecting strongly performing thermoelectric legs. Moreover, thermal stresses are reduced in the unileg models compared with the unicouple system because the thermal expansion coefficient mismatch between dissimilar annular TE legs is eliminated.

采用多级模块改善环形热电发电机（ATEGs）在圆形应用中的温度分布。本文研究了单联级联气体发生器的性能，并首次与单联级联气体发生器进行了比较。采用三维有限元模拟分析了两级和三级结构的热电功率和热应力。在两阶段模型中，在顶部和底部阶段分别使用Half-Heusler和skuturite作为热电材料。在三级系统中，碲化铋被插入底部阶段，低于半赫斯勒和滑石阶段。结果表明，两级单偶和单级级egats分别产生0.25 W和0.29 W的TE功率。相比之下，三级单偶和单偶系统分别产生0.41 W和0.46 W。通过选择性能强的热电腿，联合多级模型优于单偶级联模型。此外，由于消除了不同环形TE支腿之间的热膨胀系数不匹配，单偶模型中的热应力比单偶系统中的热应力更小。

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引用次数: 0

An approach for numerical investigation of 3D lead‑bismuth helical coiled once-through steam generator based on GeN-Foam solver 基于GeN-Foam求解器的三维铅铋螺旋盘绕式蒸汽发生器数值研究方法

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-20 DOI: 10.1016/j.icheatmasstransfer.2026.110586

Yupeng Yang , Scolaro Alessandro , Fiorina Carlo , Giovanni Nervi , Chenglong Wang , Yuan Zhou , Yuan Yuan , Suizheng Qiu

Helical coil once-through tube steam generators (HCOTSGs) represent a promising heat exchanger solution for future applications in small-scale Lead-Bismuth Eutectic (LBE) fast reactors. Due to their complex geometry and thermal-hydraulic behavior, full-scale 3D simulation tools are essential for design optimization and safety assessment. In this work, a thermal-hydraulic model of an LBE HCOTSG is developed using the GeN-Foam multi-physics platform. It is employed to investigate flow and heat transfer characteristics under representative operating conditions. The model employs a porous-medium approach and is first validated against separate-effect tests for the two-phase water-steam flow on the tube side and the LBE flow on the shell side. Additionally, the coupled heat transfer process is compared with detailed high-fidelity simulations, demonstrating good agreement while significantly reducing computational cost. Following validation, the HCOTSG behavior is analyzed under both normal and off-normal conditions. Temperature changes and temperature differences at different radial locations were obtained. The study examines the influence of flow fluctuations and inlet non-uniformities on phase distribution and thermal performance. Overall, this study provides a comprehensive analysis of the thermal-hydraulic behavior of LBE HCOTSGs and demonstrates the capability of the developed tool to efficiently support design and safety evaluations.

螺旋盘管直通管蒸汽发生器（HCOTSGs）代表了一种有前途的热交换器解决方案，用于未来的小型铅铋共晶（LBE）快堆。由于其复杂的几何形状和热液特性，全尺寸三维仿真工具对于设计优化和安全评估至关重要。在这项工作中，利用GeN-Foam多物理场平台开发了LBE HCOTSG的热工模型。用它来研究代表性工况下的流动和传热特性。该模型采用多孔介质方法，并首先通过管侧两相水-蒸汽流动和壳侧LBE流动的分离效应试验进行了验证。此外，将耦合传热过程与详细的高保真模拟进行了比较，结果表明，在显著降低计算成本的同时，耦合传热过程具有良好的一致性。验证后，分析HCOTSG在正常和非正常条件下的行为。得到了不同径向位置的温度变化和温差。研究了流动波动和进口不均匀性对相分布和热性能的影响。总的来说，本研究提供了LBE HCOTSGs的热水力行为的综合分析，并证明了开发的工具能够有效地支持设计和安全评估。

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引用次数: 0

Asymmetric unstable natural convection in an open-ended vertical channel with hot-cold walls 具有冷热壁的开放式垂直通道中的不对称不稳定自然对流

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-19 DOI: 10.1016/j.icheatmasstransfer.2026.110568

Chung-Gang Li

The unstable flow phenomena induced by natural convection in an open-ended vertical channel with an asymmetric hot-cold wall configuration are numerically investigated. Unlike classical vertical channel flows, where buoyancy-driven motion remains steady at moderate Rayleigh numbers (Ra = 5.23 × 10⁵–4.18 × 10⁶), the present configuration exhibits pronounced unsteady behavior due to the interaction of counter-rotating flows adjacent to opposing thermal boundaries. The Grossmann–Lohse (GL) theory, originally developed for horizontal Rayleigh–Bénard convection, is found to effectively characterize the kinetic and thermal dissipation structures in this asymmetric vertical system. These instabilities enhance heat transfer by approximately 20%, indicating a distinct scaling behavior from conventional channel flow. A compressible solver with absorbing and non-reflecting boundary conditions is employed to accommodate bidirectional inlet–outlet flow without prescribing the flow rate.

对具有非对称冷热壁结构的开放式垂直通道中自然对流引起的不稳定流动现象进行了数值研究。与经典的垂直通道流动不同，在传统的垂直通道流动中，浮力驱动的运动在中等瑞利数（Ra = 5.23 × 105-4.18 × 106）下保持稳定，由于靠近相反热边界的反向旋转流动的相互作用，目前的结构表现出明显的不稳定行为。Grossmann-Lohse （GL）理论，最初是为水平rayleigh - b纳德对流而发展起来的，被发现可以有效地描述这种不对称垂直系统的动力学和热耗散结构。这些不稳定性提高了约20%的传热，表明与传统通道流动相比有明显的结垢行为。采用一种具有吸收和非反射边界条件的可压缩求解器，在不规定流量的情况下适应双向进出口流动。

引用次数: 0

Decay heat effects on standards-compliant vacuum drying of spent nuclear fuel 衰变热对符合标准的乏核燃料真空干燥的影响

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-01-19 DOI: 10.1016/j.icheatmasstransfer.2026.110561

Ji Hwan Lim , Seung-Hwan Yu , Kyung-Wook Shin , Nam-Hee Lee

The vacuum drying of spent nuclear fuel (SNF) canisters is a critical safety operation that requires the rapid and reliable removal of residual water while simultaneously mitigating the risks of ice formation and excessive thermal excursions. This study presents a comprehensive experimental evaluation comparing the conventional step-wise (STEP-WISE) depressurization protocol against a sophisticated pump-modulated strategy (NEW METHOD) across four distinct decay-heat levels ranging from 0 to 800 W. Unlike traditional methods that rely on static pressure holds, the NEW METHOD utilizes a targeted flow-throttling technique (reducing exhaust from 600 to ∼100 L·min⁻¹) specifically within a ∼ 40-Torr transport-control corridor. This operational approach ensures a continuously sub-saturated headspace, which effectively prevents the re-attachment of detached moisture and facilitates the purging of non-condensable gases from complex micro-geometries. Our quantitative results demonstrate that the NEW METHOD consistently accelerates early-stage evaporation kinetics, achieving average evaporation rate improvements of 34–56% (ratios of 1.34–1.56) compared to the STEP-WISE baseline. Notably, at a high decay heat of 800 W, the NEW METHOD achieved a significantly lower final residual moisture of approximately 160 mg, whereas the STEP-WISE method left nearly double that amount (∼305 mg). This divergence is attributed to a ‘dry hot endgame’ mechanism that promotes the de-hydroxylation of surface-bound water under uninterrupted venting conditions. Throughout all tests, the peak cladding temperatures remained well within established safety margins (≤ ∼ 203 °C), proving that the proposed strategy optimizes drying completeness without compromising thermal integrity. These findings underscore that dynamic operational control is the primary governing factor in ensuring standards-compliant SNF drying.

乏燃料（SNF）罐的真空干燥是一项关键的安全操作，需要快速可靠地去除残余水，同时减轻结冰和过度热漂移的风险。本研究提出了一个综合的实验评估，比较了传统的逐步降压方案（step-wise）和复杂的泵调制策略（NEW METHOD）在4种不同的衰变热水平（从0到800 W）上的差异。与依赖静压保持的传统方法不同，新方法利用了一种有针对性的流量节流技术（将排气从600减少到~ 100 L·min−1），特别是在~ 40-Torr的运输控制通道内。这种操作方法确保了持续的亚饱和顶空，有效地防止了分离水分的重新附着，并有利于从复杂的微观几何形状中清除不可冷凝气体。我们的定量结果表明，与STEP-WISE基线相比，新方法持续加速了早期蒸发动力学，平均蒸发速率提高了34-56%（比率为1.34-1.56）。值得注意的是，在800 W的高衰变热下，新方法的最终残余水分显著降低，约为160 mg，而STEP-WISE方法的残余水分几乎是前者的两倍（~ 305 mg）。这种差异归因于“干热终局”机制，该机制在不间断的排气条件下促进地表水的去羟基化。在所有测试中，峰值包层温度保持在既定的安全范围内（≤~ 203°C），证明所提出的策略在不影响热完整性的情况下优化了干燥完整性。这些发现强调，动态操作控制是确保符合标准的SNF干燥的主要控制因素。

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引用次数: 0