Annals of Nuclear Energy最新文献_第5页

Numerical study on the turbulent heat transfer behaviors of the fuel assembly with spacer wires in lead-based fast reactors based on four-equation model 基于四方程模型的铅基快堆带间隔线燃料组件湍流传热行为数值研究

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-23 DOI: 10.1016/j.anucene.2025.112066

Yunxiang Li , Runsheng Yang , Yuefeng Guo , Xingkang Su , Yuping Zhou , Jian Hong , Yuxing Liu , Zinan Huang , Xin Su , Youpeng Zhang , WenJun Hu , Long Gu

The thermal–hydraulic behavior of liquid lead–bismuth eutectic in wire-wrapped fuel assemblies plays a crucial role in the safety design of the CiADS sub-critical reactor. A four-equation model, which incorporates both dynamic and thermal time scales to transport the turbulent Prandtl number, may enhance the predictive accuracy of heat transfer in LBE. In this work, an in-house solver, LBE4EqnFoam, was developed on the open-source CFD platform OpenFOAM and applied to the simulation of the CiADS wire-wrapped fuel assembly. High-fidelity calculations of the bundle section suggest that the pressure field exhibits non-uniform “high-pressure” and “low-pressure” regions along the wire-winding direction. The predicted pressure drop shows good agreement with the Cheng and Todreas correlation, with a maximum relative deviation of less than 9 %. The coolant velocity distribution was found to be opposite to the pressure field, with lower velocities inside the “high-pressure” regions. Strong fluctuations of transverse secondary flows were observed among different subchannels, and their intensity increased near the spacers, reaching a maximum of 0.33. The average coolant temperature in the edge and corner channels tended to be lower than the bulk average, while the highest coolant temperature, up to 684 K, occurred within the internal subchannels. The Nusselt number distribution indicates that heat transfer becomes nearly fully developed between the 5th and 6th pitches. The wall hot-spot factor was larger in the internal channels, reflecting a less uniform wall temperature compared with the cross-sectional average. Furthermore, the strongest coolant temperature fluctuations were located between the edge and outer internal channels, whereas the maximum turbulent Prandtl number appeared in the internal subchannels.

线包燃料组件中液态铅铋共晶的热水力特性对CiADS亚临界反应堆的安全设计具有重要意义。结合动力和热时间尺度来传递湍流普朗特数的四方程模型可以提高LBE中传热的预测精度。在这项工作中，在开源CFD平台OpenFOAM上开发了内部求解器LBE4EqnFoam，并将其应用于CiADS线包燃料组件的仿真。对管束截面的高保真度计算表明，压力场沿绕丝方向呈现不均匀的“高压”和“低压”区域。预测压降与Cheng和Todreas相关性吻合较好，最大相对偏差小于9 %。研究发现，冷却剂的速度分布与压力场相反，在“高压”区域内速度较低。横向二次流在不同子通道间有较强的波动，其强度在间隔附近增大，最大可达0.33。边缘和角落通道的平均冷却液温度往往低于整体平均温度，而内部子通道的冷却液温度最高，达到684 K。努塞尔数分布表明，热传递在第5和第6音高之间几乎完全发展。壁面热点因子在内部通道中较大，反映了壁面温度与截面平均温度相比不均匀。冷却剂温度波动最剧烈的区域位于内部通道边缘和外部通道之间，而最大的湍流普朗特数出现在内部子通道中。

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引用次数: 0

Investigation on cross flow characteristics in a 5 × 5 rod bundle with a bowed central rod based on PIV quantification 基于PIV量化的5 × 5中心弯曲杆束内交叉流动特性研究

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-23 DOI: 10.1016/j.anucene.2025.112087

Shan Zhou , Jianqiang Shan , Li Jiang , Yudong Zha , Junliang Guo , Tenghua Shu , Miao Gui

Based on Particle Image Velocimetry technology, this study conducted cross flow measurement experiments and analysis under rod bowing conditions, investigating the effects of different gap closures (0 %, 50 %, 75 %, 100 %) and Reynolds numbers (Re) on the cross flow characteristics downstream of mixing vanes. The results show that rod bowing significantly affects the cross flow generated by mixing vanes by changing subchannel areas and gap widths, leading to cross flow interruption or redirection, and vortex deflection in subchannels. Cross flow is enhanced when the action direction of rod bowing is consistent with that of mixing vanes, and weakened by counteraction when opposite. The Re effect is not obvious in the near field of the mixing grid. However, at and above 10.6 D_h, cross flow increases with increasing Re, high-intensity cross flow migrates toward subchannel gaps. The results provide data validation for the development of subchannel codes and CFD to improve the prediction of thermal–hydraulic parameters under rod bowing.

基于粒子图像测速技术，在杆弯曲条件下进行了交叉流测量实验和分析，研究了不同间隙关闭度（0%、50%、75%、100%）和雷诺数（Re）对混合叶片下游交叉流特性的影响。结果表明，杆杆弯曲通过改变子通道面积和间隙宽度，显著影响混合叶片产生的横流，导致横流中断或重定向，导致子通道内涡流偏转。当杆弯曲作用方向与混合叶片作用方向一致时，交叉流动增强，反之则受反作用力减弱。混合栅近场的Re效应不明显。而在10.6 Dh及以上，随着Re的增加，交叉流增加，高强度的交叉流向亚通道间隙迁移。研究结果为开发子通道代码和CFD提供了数据验证，以改进杆身弯曲下的热水力参数预测。

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引用次数: 0

Multi-objective optimal path planning for radioactive environment based on modified A* algorithm 基于改进A*算法的放射性环境多目标最优路径规划

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-23 DOI: 10.1016/j.anucene.2025.112089

Haifeng Zou , Gang Jiang , Jianbin Zhou , Heng Dai , Xingan Hao , Peng Wang , Yue Peng

To address the synergistic optimization of robotic task efficiency, motion safety, and radiation exposure in radioactive environments, a multi-layer grid-based navigation map was developed through systematic analysis of environmental constraints including terrain, obstacles, and radiation fields. Building upon this spatial representation, a multi-objective path evaluation model was established to quantitatively integrate travel time, collision risk, and radiation dose. To resolve multi-objective path search and decision-making challenges, a novel Multi-Objective A* algorithm based on Grid search (MOA*-G) was proposed for optimal path planning. This framework integrates lexicographic ordering and linear weighting mechanisms to search for paths under multi-objective constraints. A grid search strategy is employed to systematically generate and evaluate weighted combinations to select the optimal solution. The methodology was validated through simulations and comparative experiments with traditional A* and Minimum Dose A* (MDA*) algorithms. Results demonstrate that MOA*-G achieves superior comprehensive performance, exhibiting median reductions of at least 55.4% in collision risk and at least 38.7% in radiation dose compared to traditional A*, while maintaining the increase in travel time below 1.6% (median). This indicates MOA*-G provides an effective multi-objective balancing scheme for robotic path planning in radioactive environments.

为了解决辐射环境中机器人任务效率、运动安全和辐射暴露的协同优化问题，通过系统分析地形、障碍物和辐射场等环境约束，开发了基于网格的多层导航地图。在此空间表示的基础上，建立了多目标路径评价模型，定量地综合了旅行时间、碰撞风险和辐射剂量。为解决多目标路径搜索和决策难题，提出了一种基于网格搜索的多目标a *算法（MOA*-G）进行最优路径规划。该框架集成了字典排序和线性加权机制，以在多目标约束下搜索路径。采用网格搜索策略系统地生成和评估加权组合，以选择最优解。通过仿真和与传统A*和最小剂量A* (MDA*)算法的对比实验验证了该方法的有效性。结果表明，MOA*-G具有优越的综合性能，与传统A*相比，碰撞风险中位数至少降低55.4%，辐射剂量中位数至少降低38.7%，而旅行时间增幅保持在1.6%以下（中位数）。这表明MOA*-G为放射性环境下机器人路径规划提供了有效的多目标平衡方案。

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引用次数: 0

Experimental and mechanistic study on critical heat flux of R134a in tube under inclined conditions 倾斜条件下R134a管内临界热流密度的实验与机理研究

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-22 DOI: 10.1016/j.anucene.2025.112078

Huanjun Kong, Ya Li, Jianqiang Shan, Miao Gui

This study presents an experimental investigation on the characteristics of critical heat flux (CHF) in inclined circular tube. The test section comprised a circular tube with an inner diameter of 8 mm and a maximum effective heating length of 1600 mm. Using R134a as the working fluid, experiments were performed over a pressure range of 1.6–2.7 MPa, mass fluxes of 1000–3000 kg/m²^/s, and inclination angles of 0°–25°. The results demonstrate that inclination generally degrades CHF at low outlet quality, with the deterioration effect enhanced by reduced mass flux and increased inclination angle. CHF has deteriorated by approximately 46 % at most. In contrast, CHF remains largely insensitive to inclination under high quality conditions. The refined subchannel analysis provides more localized void fraction data, yielding a more accurate understanding of the influencing mechanisms. It indicates that when CHF occurs at a uniform heat flux, the void fraction in the upper region of the channel remains consistent across different inclination angles. The influence of inclination on CHF is intrinsically linked to flow patterns: under bubbly flow conditions, the void fraction at the top of the inclined tube is lower than that in vertical configurations; however, when the flow pattern transitions to slug flow, the void fraction in the inclined tube aligns with that observed in vertical tubes.

本文对斜圆管内临界热流密度特性进行了实验研究。试验截面为内径为8mm的圆管，最大有效加热长度为1600mm。实验以R134a为工质，压力范围为1.6 ~ 2.7 MPa，质量通量为1000 ~ 3000 kg/m2/s，倾角为0°~ 25°。结果表明：在出口质量较低的情况下，倾角对CHF的降解作用普遍存在，质量通量的减小和倾角的增大增强了CHF的降解作用。瑞士法郎最多贬值约46%。相比之下，在高质量条件下，CHF对倾角基本不敏感。精细化的子通道分析提供了更局部的孔隙分数数据，从而更准确地理解了影响机制。结果表明，当热通量均匀发生CHF时，通道上部区域的空隙率在不同的倾角下保持一致。倾斜对CHF的影响与流动形态有着内在的联系：在气泡流动条件下，倾斜管顶部的空隙率低于垂直配置；然而，当流型转变为段塞流时，倾斜管中的空隙率与垂直管中的空隙率一致。

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引用次数: 0

Numerical study on migration and solidification behavior of molten Fe-Zr in UO2-ZrO2 debris bed Fe-Zr熔液在UO2-ZrO2碎屑床中的迁移和凝固行为的数值研究

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-22 DOI: 10.1016/j.anucene.2025.112076

Peitao Yao , Yong Li , Gen Li , Jinchen Gao , Yunlong Liao

The migration and solidification behavior of molten metal in porous debris bed is a key phenomenon during the late stage of nuclear reactor severe accident. If the heat of the debris bed cannot be effectively released, the corium may ablate the bottom wall of the lower plenum, thereby threatening the integrity of reactor pressure vessel (RPV). In this study, to understand this key phenomenon, the explicit moving particle simulation (EMPS) method is employed to simulate the migration and solidification behavior of melt in a three-dimensional slice debris bed. In the hypothetical cases with a porosity range of 0.34 to 0.437, the molten pool is formed above the debris bed. Below the molten pool, the melt almost fills the debris bed at the upper region and its filling proportion in debris bed gradually decreases in the direction of melt migration. With the porosity increasing, the height of molten pool decreases and the melt migration depth increases correspondingly. As the increase of melt initial temperature, both the migration depth and solidification fraction of the melt present an increased tendency in the temperature range of 1300 K to 1500 K. However, the results of the cases with different melt initial heights have little difference, indicating that the influence of melt initial height is slight. Similar results can be found in the sensitive analysis of debris bed initial temperature, where both the migration depth and solidification fraction of the melt increase with the debris bed initial temperature. The difference of migration depth is only 0.204 m when the debris bed temperature changes from 450 K to 850 K.

熔融金属在多孔碎屑床中的迁移和凝固行为是核反应堆严重事故后期的一个关键现象。如果碎屑床的热量不能有效释放，堆芯可能会烧蚀下静压室的底壁，从而威胁到反应堆压力容器的完整性。为了理解这一关键现象，本研究采用显式移动粒子模拟（explicit moving particle simulation， EMPS）方法模拟了熔体在三维片状碎屑床中的迁移和凝固行为。在孔隙度为0.34 ~ 0.437的假设情况下，熔池在碎屑床上方形成。熔池下方，熔体在上部区域几乎充填碎屑层，其在碎屑层中的充填比例沿熔体迁移方向逐渐减小。随着孔隙率的增大，熔池高度减小，熔体迁移深度相应增大。随着熔体初始温度的升高，熔体的迁移深度和凝固分数在1300 ~ 1500 K范围内均呈增加趋势。而不同熔体初始高度情况下的结果差异不大，说明熔体初始高度的影响较小。在碎屑床初始温度的敏感性分析中也发现了类似的结果，随着碎屑床初始温度的升高，熔体的迁移深度和凝固分数都增加。当碎屑层温度从450 K变化到850 K时，迁移深度的差异仅为0.204 m。

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引用次数: 0

Development and validation of a dynamic radiation field calculation method for nuclear facility decommissioning 核设施退役动态辐射场计算方法的开发与验证

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-22 DOI: 10.1016/j.anucene.2025.112086

Jifeng Hu , Yongkuo Liu , Zhitao Chen , Nan Chao , Xiaochang Zheng , Zhongkun Liu

During nuclear decommissioning, the cutting of radioactive components results in a dynamically evolving radiation field. To address this challenge, we developed VDPK, a high-performance point-kernel code. It incorporates three-dimensional activity distributions into voxelized source models, and do the radiation field calculation via the rigorous two-step (R2S) method. The code incorporates an online cutting algorithm based on Boolean operations, enabling synchronous updates of the radioactive source geometry during cutting simulation. Computational efficiency is enhanced through integrated fast voxel traversal and a Linear Bounding Volume Hierarchy (LBVH) acceleration structure. Validation against OpenMC benchmarks and literature data demonstrates calculation errors within 8.18 % for unshielded conditions, 5.17 % for single-layer shielding, and 15.99 % for multilayer shielding. For complex non-uniform sources under dynamic cutting, the maximum deviation remains below 16.75 %. These findings demonstrate that VDPK has the potential to perform efficient and accurate simulations of dynamic radiation fields, thereby paving the way for its future application in supporting the safety assessment and operational planning of decommissioning projects.

在核退役过程中，放射性成分的切割导致了一个动态演变的辐射场。为了解决这个问题，我们开发了VDPK，一种高性能的点内核代码。将三维活度分布纳入体素源模型，采用严格两步法（R2S）进行辐射场计算。该代码包含一个基于布尔运算的在线切割算法，在切割模拟期间实现放射源几何形状的同步更新。通过集成快速体素遍历和线性边界体层次（LBVH）加速结构，提高了计算效率。对OpenMC基准测试和文献数据的验证表明，非屏蔽条件下的计算误差在8.18%以内，单层屏蔽条件下的计算误差为5.17%，多层屏蔽条件下的计算误差为15.99%。对于动态切削下的复杂非均匀源，最大偏差保持在16.75%以下。这些发现表明，VDPK有潜力对动态辐射场进行高效、准确的模拟，从而为其未来在支持退役项目的安全评估和运营规划方面的应用铺平了道路。

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引用次数: 0

Inverse determination of Cr diffusion coefficients in Zr alloys via Fick’s law and multi-objective optimization 用菲克定律和多目标优化反求Zr合金中Cr扩散系数

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-20 DOI: 10.1016/j.anucene.2025.112077

Dong Wang , Shihao Wu , Kai Lu , Yapei Zhang , Xi Liu , Jiaxin Zhang , Kui Ge

Cr-coated Zr alloy cladding stands as the near-term research and development focus for accident tolerant fuel. Accurately evaluating the survival time of Cr coatings under high-temperature conditions holds significant importance for reactor safety analysis. This evaluation must consider Cr-Zr interactions (including ZrCr₂ growth and Cr dissolution within the Zr substrate), as their contribution to coating consumption is comparable to that of oxidation. We have modified the previously developed Fick’s-law-based SICO code to adapt to the simulation of Cr coating diffusion loss. Here, the Cr diffusion coefficients of Zr and ZrCr₂ are key parameters influencing the simulation accuracy. In this study, a multi-objective optimization method was employed to obtain the Cr diffusion coefficients for achieving best match between simulation results and experimental data. Sensitivity tests on Cr diffusion coefficients were carried out using the adapted SICO code. The Residual Sum of Squares (RSS) between simulation results and experimental data was calculated, and response surfaces of RSS with respect to Cr diffusion coefficients were constructed. The NSGA-Ⅱ algorithm and TOPSIS method were applied to obtain the optimal combination of diffusion coefficients for each case. Ultimately, the optimal temperature-dependent correlations for the Cr diffusion coefficients were obtained by fitting the optimal diffusion coefficients with Arrhenius equation. Compared with applying literature-reported correlations, applying our optimized correlations significantly improves the prediction accuracy of Cr and ZrCr₂ thicknesses. The Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and Mean Relative Error (MRE) between simulation results and experimental data are reduced by over 20 %, with a maximum reduction exceeding 50 %.

cr包覆Zr合金包层是近期耐事故燃料的研究和开发重点。准确评估Cr涂层在高温条件下的存活时间对反应堆安全性分析具有重要意义。这种评估必须考虑Cr-Zr相互作用（包括ZrCr2生长和Cr在Zr衬底内的溶解），因为它们对涂层消耗的贡献与氧化相当。我们修改了先前开发的基于菲克定律的SICO代码，以适应Cr涂层扩散损失的模拟。其中，Zr和ZrCr2的Cr扩散系数是影响模拟精度的关键参数。本研究采用多目标优化方法获取Cr扩散系数，使模拟结果与实验数据达到最佳匹配。采用调整后的SICO规范对Cr扩散系数进行了敏感性试验。计算了模拟结果与实验数据的残差平方和（RSS），构建了RSS随Cr扩散系数的响应曲面。采用NSGA-Ⅱ算法和TOPSIS方法对不同情况下的扩散系数进行优化组合。最后，利用Arrhenius方程拟合最优扩散系数，得到了Cr扩散系数的最优温度相关关系。与应用文献报道的相关性相比，应用我们优化的相关性显著提高了Cr和ZrCr2厚度的预测精度。仿真结果与实验数据之间的均方根误差（RMSE）、平均绝对误差（MAE）和平均相对误差（MRE）降低了20%以上，最大降低幅度超过50%。

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引用次数: 0

Experimental study on the combustion characteristics of double sodium droplets in controlled conditions 可控条件下双钠液滴燃烧特性的实验研究

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-20 DOI: 10.1016/j.anucene.2025.112069

Ding-hao Wang , Yao-long Ma , Zhi-gang Zhang , Jia-zhe Pu , Xiao-dong Wei

During the operation of sodium-cooled fast reactors, liquid sodium leakage and subsequent fire accidents are potential risks in sodium-related facilities. This paper focuses on the combustion characteristics and mechanism of double sodium droplets under the initial conditions with temperatures of 200–350 °C and oxygen concentrations of 4–21 % VOL compared with the previous single droplet. The results indicate that the oxygen concentration significantly influences the morphology of columnar oxides on the droplet surface during the pre-combustion stage. Furthermore, a critical oxygen concentration threshold exists, which demarcates the transition from a surface reaction-dominated regime to a gas-phase reaction-dominated regime. Once the oxygen concentration exceeds this threshold, the combustion rate and peak temperature of the double droplets increase markedly. Additionally, a higher initial sodium temperature substantially shortens the duration of the pre-combustion stage. A fundamental asymmetry in droplet interaction is revealed: inhibitory under oxygen-lean conditions yet synergistic under oxygen-rich conditions. This research is promising for enhanced safety assessments and protective measures related with the sodium fire accident in sodium-cooled fast reactors.

在钠冷快堆运行过程中，液钠泄漏和随后的火灾事故是钠相关设施的潜在风险。本文主要研究了在初始温度为200 ~ 350℃，氧气浓度为4 ~ 21%的条件下，双钠液滴与原单钠液滴相比的燃烧特性和机理。结果表明，在燃烧前阶段，氧浓度对液滴表面柱状氧化物的形貌有显著影响。此外，存在一个临界氧浓度阈值，该阈值标志着从表面反应为主向气相反应为主转变。一旦氧浓度超过该阈值，双液滴的燃烧速率和峰值温度显著增加。此外，较高的初始钠温度大大缩短了燃烧前阶段的持续时间。揭示了液滴相互作用的基本不对称性：在贫氧条件下具有抑制作用，而在富氧条件下具有协同作用。该研究为加强钠冷快堆钠火事故的安全评价和防护措施提供了依据。

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引用次数: 0

Oxygen-dependent corrosion kinetics of 15-15Ti steel in static lead–bismuth eutectic at 500°C 15-15Ti钢在500℃静态铅铋共晶中的氧依赖腐蚀动力学

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-18 DOI: 10.1016/j.anucene.2025.112073

Shujian Tian , Jun Liu , Zhen Zhang , Lin Luo , Zhizhong Jiang , Jing Liu , Zhitao Xu , Zunqi Xiao

Corrosion of 15–15Ti austenitic stainless steel was examined in static lead–bismuth eutectic at 500°C at ∼10⁻⁶ and ∼10⁻⁸ wt% O for up to 2000 h. At high oxygen, a duplex Fe₃O₄/(Fe,Cr) ₃O₄ scale formed and grew parabolically with k_p ≈ 0.0135 μm² h⁻¹. At low oxygen, dissolution with Ni/Cr depletion and ferritization produced linear penetration ≈ 0.0093 μm h⁻¹. Extrapolation under static conditions indicates metal loss of tens of micrometers for oxidation versus millimeter scale for dissolution over 10–15 years, underscoring the need for precise oxygen control. The results provide rate constants for 15–15Ti at 500°C and link the oxygen-dependent kinetics to duplex-oxide and ferritized morphologies, supplying baseline inputs for oxygen-window planning and preliminary life assessment.

在500℃、~ 10−6和~ 10−8 wt% O条件下，对15-15Ti奥氏体不锈钢进行了静态铅铋共晶腐蚀，腐蚀时间长达2000 h。在高氧条件下，Fe3O4/(Fe,Cr) 3O4双相结垢形成并呈抛物线状生长，kp≈0.0135 μm2 h−1。在低氧条件下，随着Ni/Cr的损耗和铁素化，溶解产生的线性渗透≈0.0093 μm h−1。静态条件下的外推表明，在10-15年的时间里，氧化导致的金属损失为数十微米，而溶解则为毫米级，这强调了精确氧气控制的必要性。结果提供了在500°C下15-15Ti的速率常数，并将氧依赖动力学与双氧化物和铁化形态联系起来，为氧窗口规划和初步寿命评估提供了基线输入。

引用次数: 0

The effective dry-out temperature ahead of the rewetting quench front regime for bottom flooding at low flowrates and atmospheric pressure 低流量、低气压下底驱再湿淬火前的有效干化温度

IF 2.3 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Annals of Nuclear Energy

Pub Date : 2025-12-17 DOI: 10.1016/j.anucene.2025.112057

E.D. Poulopoulou , N.M. Lymperea , A.A. Nikoglou , N.P. Petropoulos

The purpose of this study is to identify the values of the temperature between the transition boiling and the dry-out regime within the bottom flooding quench front. This temperature (or T₀) is, theoretically, supposed to be the wet front temperature that corresponds to the minimum film boiling heat flux. The study is not based on direct T₀ measurements but on indirect exploitation of experimental data leading to models, which are expected to provide at least a value or even a range of the T₀ values, and also a discussion on the path to the outcome. The data themselves are quite plenty, in the hundreds, each providing an estimated wet-front velocity associated with a wall temperature, a subcooling temperature and a flowrate. All experiments have been conducted in atmospheric pressure and low flowrates in the range up to 3 LPM.

本研究的目的是确定底部驱油淬火锋中过渡沸腾和干燥状态之间的温度值。理论上，这个温度（或T0）应该是与最小膜沸腾热通量相对应的湿锋温度。这项研究不是基于直接的T0测量，而是基于间接利用实验数据得出的模型，这些模型预计将提供至少一个值甚至一个范围的T0值，并对结果的路径进行讨论。数据本身非常丰富，有数百个，每个数据都提供了与壁面温度、过冷温度和流量相关的预估湿锋速度。所有的实验都是在大气压和低流量下进行的，最高可达3lpm。

引用次数: 0