Nuclear Engineering and Technology最新文献_第7页

Influence of dissolved hydrogen and IG Cr carbide on the oxidation behavior of Alloy 600 in hydrogenated primary water 溶解氢和 IG 碳化铬对合金 600 在氢化原水中氧化行为的影响

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-08-03 DOI: 10.1016/j.net.2024.08.003

Yun Soo Lim, Dong Jin Kim, Sung Woo Kim, Seong Sik Hwang, Sung Hwan Cho, Hong Pyo Kim

The internal oxidation (IO) and preferential intergranular oxidation (PIO) behavior of Alloy 600 depending on the dissolved hydrogen (DH) content and the IG Cr carbide in hydrogenated primary water were characterized in detail using analytical electron microscopy techniques. The oxidation layer was unstable when the DH concentration was such that Ni was in the vicinity of Ni/NiO equilibrium and it could easily be peeled off. Hence, the grain boundaries of the bare metal were attacked. PIO occurred and Cr-rich oxide identified as CrO was formed at the oxidized grain boundary. NiO emerged when the DH concentration was such that Ni was in an oxidizing state, whereas Ni enrichment occurred inside the oxidized grain boundary when the DH concentration was such that Ni was in a reducing state with respective to Ni/NiO equilibrium. The IG Cr carbide strongly affected the PIO behavior by means of the consumption of oxygen penetrating into the grain boundary. The depth of the IO layer decreased as the DH concentration increased. The different oxidation behaviors depending on the DH content and IG Cr carbide are believed to affect the PWSCC resistance of Alloy 600 significantly.

利用分析电子显微镜技术详细描述了合金 600 的内部氧化（IO）和优先晶间氧化（PIO）行为，这取决于氢化原水中的溶解氢（DH）含量和 IG 碳化铬。当 DH 浓度使 Ni 处于 Ni/NiO 平衡附近时，氧化层不稳定，很容易剥离。因此，裸金属的晶界受到侵蚀。发生了 PIO，在氧化的晶界处形成了富铬氧化物，即 CrO。当 DH 浓度使镍处于氧化状态时，会出现 NiO；而当 DH 浓度使镍处于还原状态时，氧化晶界内会出现镍/NiO 平衡。通过消耗渗入晶界的氧气，IG 碳化铬对 PIO 行为产生了强烈影响。IO 层的深度随着 DH 浓度的增加而减小。不同的氧化行为取决于 DH 含量和 IG 碳化铬，相信这将对合金 600 的耐 PWSCC 性能产生重大影响。

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引用次数: 0

Technical studies about the prestressed insulation cylinder of HL-3 tokamak's center-post 有关 HL-3 托卡马克中柱预应力绝缘筒的技术研究

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-08-03 DOI: 10.1016/j.net.2024.08.001

Yin Qiu, Ming Li, Xiaolong Liu, Qinghua Ren, Tao Lin, Jian Liu

The TF coil of HL-3 consists of 20 D-shaped demountable bundles, and all their L-shaped center sections are bonded together as the center-post. To increase its overall rigidity to resist torsional loads and avoid de-bonding failure, the center-post is wrapped by an insulation cylinder with enough prestress. Additionally, the insulation cylinder needs to be of good dimensional precision because the CS coil is winded around it. This paper describes the results of the technical studies carried out during the development of the insulation cylinder, including material selection, parameter calculation, enlacing tests and curing tests.

HL-3 的 TF 线圈由 20 个 D 型可拆卸线束组成，其所有 L 型中心部分粘结在一起作为中柱。为了提高其整体刚度以抵抗扭转载荷，并避免脱粘失效，中柱由具有足够预应力的绝缘圆筒包裹。此外，由于希尔思线圈是缠绕在绝缘圆筒上的，因此绝缘圆筒需要有良好的尺寸精度。本文介绍了在绝缘筒开发过程中进行的技术研究结果，包括材料选择、参数计算、铺设试验和固化试验。

引用次数: 0

Rapid determination of the migration parameters of nuclides in intact granite rock under the action of electric field 在电场作用下快速测定完整花岗岩石中核素的迁移参数

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-08-02 DOI: 10.1016/j.net.2024.07.062

Xinyu Wang, Xiaojie Li, Yongmei Li, Longcheng Liu, Shuo Meng, Chunguang Li, Zhenzhong Liu, Xiaodong Li, Kaixuan Tan

Deep geologic disposal has been widely accepted as a strategy for long-term disposal of the high-level radioactive waste. It is principal to obtain the migration parameters of radionuclides in natural barrier, such as granite, of a high-level radioactive waste repository for safety assessment of the repository. To quickly determine the diffusion and sorption properties of nuclides in intact granite, two tracers, I and ReO, were tested with a modified electromigration device, by imposing a constant voltage over an intact Beishan granitic rock sample. The breakthrough curves of I and ReO were obtained under condition of five different voltages. To interpret the electromigration experimental results with more confidence, an advection-dispersion model based on first-order adsorption kinetics was developed in this study. Data analysis of the breakthrough curves by this model suggest that the effective diffusion coefficients of I and ReO in intact Beishan granodiorite rock are (6.81 ± 0.53) × 10 m/s and (6.45 ± 0.07) × 10 m/s, respectively. While the distribution coefficient of the two ions are (9.06 ± 1.13) × 10 m/kg and (9.81 ± 0.13) × 10 m/kg, respectively. This indicates that I and ReO hardly adsorb in Beishan granodiorite rock.

深部地质处置作为一种长期处置高放射性废物的策略已被广泛接受。获取放射性核素在高放射性废物处置库天然屏障（如花岗岩）中的迁移参数是对处置库进行安全评估的关键。为了快速确定核素在完整花岗岩中的扩散和吸附特性，利用改进的电迁移装置，在完整的北山花岗岩样本上施加恒定电压，对 I 和 ReO 两种示踪剂进行了测试。在五种不同电压条件下获得了 I 和 ReO 的突破曲线。为了更有把握地解释电迁移实验结果，本研究建立了一个基于一阶吸附动力学的平流-分散模型。根据该模型对突破曲线进行的数据分析表明，I 和 ReO 在完整北山花岗闪长岩中的有效扩散系数分别为 (6.81 ± 0.53) × 10 m/s 和 (6.45 ± 0.07) × 10 m/s。而这两种离子的分布系数分别为（9.06 ± 1.13）×10 m/kg和（9.81 ± 0.13）×10 m/kg。这表明 I 和 ReO 在北山花岗闪长岩中几乎不吸附。

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引用次数: 0

Investigation on structural failure criteria and material property uncertainties of prestressed concrete containment structure 预应力混凝土安全壳结构失效标准和材料特性不确定性研究

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-08-02 DOI: 10.1016/j.net.2024.07.060

Woo-Min Cho, Han-Sang Woo, Yoon-Suk Chang

This study is to examine load-carrying capacity of a prestressed concrete containment vessel under the structural failure mode test non-linear finite element (FE) analyses. Firstly, suitability of three candidate structural failure criteria was evaluated at ambient temperature condition, of which results showed that the maximum principal strain-based one predicts ultimate pressure capacity (UPC) most closely with the test data. Effect of increasing temperature corresponding to a postulated severe accident-induced condition was investigated and the UPC exhibited reduction ratios of 1.19–1.49% at the peak temperature of 200 °C approximately depending on each failure criterion. Finally, parametric FE analyses at 95% confidence level were performed to quantify effect of material property uncertainties. Overall, the impact of altered material properties of concrete and rebar was higher than that of tendon prestress, and the increase of UPC in upper bound cases exceeded the decrease of UPC in lower bound cases.

本研究旨在研究预应力混凝土安全壳在结构失效模式试验非线性有限元（FE）分析下的承载能力。首先，在常温条件下评估了三种候选结构失效标准的适用性，结果表明，基于最大主应变的结构失效标准预测的极限承压能力（UPC）与试验数据最为接近。研究了温度升高对假定的严重事故诱发条件的影响，根据不同的失效标准，在峰值温度 200 °C 时，UPC 的降低率约为 1.19-1.49%。最后，进行了置信度为 95% 的参数 FE 分析，以量化材料特性不确定性的影响。总体而言，混凝土和钢筋的材料特性改变的影响大于肌腱预应力的影响，在上限情况下 UPC 的增加超过了下限情况下 UPC 的减少。

引用次数: 0

Enhancing equipment qualification testing facility for nuclear power plants: Achieving rapid temperature and pressure increase during design basis events 加强核电站的设备鉴定测试设施：在设计基础事件中实现温度和压力的快速上升

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-07-31 DOI: 10.1016/j.net.2024.07.058

Kyungha Ryu, Seonggyu Cho, Taeho Roh, Sangkyo Kim, Taekook Park, Taehyun Lee, Jongwon Park, Jaehyun Cho

The present study focuses on the development of an equipment qualification (EQ) testing facility for Class 1E equipment in nuclear power plants (NPPs), emphasizing the need to ensure safety functions under design basis events (DBEs). The Republic of Korea (ROK) has implemented international safety standards to support large NPP projects, necessitating the development of domestic EQ testing facilities to reduce the dependence on foreign facilities. To address this need, herein, a specialized facility capable of simulating harsh DBE conditions that may occur in NPPs in ROK was constructed. Through exhaustive research, target temperature and pressure profiles were developed for pressurized water reactors, and a superheated steam injection technique was devised for rapid temperature and pressure changes. The present study contributes to the advancement of domestic EQ testing capabilities, achieving up to 230 °C and 700 kPa within 30 s.

本研究的重点是开发核电站 1E 级设备的设备鉴定（EQ）测试设施，强调在设计基础事件（DBE）下确保安全功能的必要性。大韩民国（ROK）已实施国际安全标准来支持大型 NPP 项目，因此有必要开发国内 EQ 测试设施，以减少对国外设施的依赖。为了满足这一需求，我们在此建造了一个能够模拟韩国核电站中可能出现的恶劣 DBE 条件的专门设施。通过详尽的研究，为压水反应堆开发了目标温度和压力曲线，并设计了过热蒸汽喷射技术，以实现快速的温度和压力变化。本研究有助于提高国内 EQ 测试能力，在 30 秒内达到 230 °C 和 700 kPa。

引用次数: 0

Characterization of evolution of reactive transport parameters during leaching process of sandstone uranium ore by combining porosity and lacunarity 结合孔隙度和裂隙度分析砂岩型铀矿浸出过程中反应输运参数的演变特征

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-07-30 DOI: 10.1016/j.net.2024.07.057

Haiying Fu, Shuai Wang, Deming Tan, Guicheng He, Meng Lian, Zhonghua Zhu, Dexin Ding

During the in-situ leaching process of sandstone uranium ore deposits, the dynamic evolution of reactive transport parameters, including permeability, tortuosity, and specific surface area (SSA), plays a crucial role in solution flow and solute transport. Characterizing the evolution of these parameters is essential for understanding the leaching process. However, the heterogeneous pore structure of sandstone renders porosity alone insufficient to capture changes in these parameters. This study combines porosity and lacunarity to comprehensively characterize these parameters. For this purpose, leaching experiments were conducted on sandstone uranium ore samples, and CT imaging was performed at different leaching time points. The evolution of reactive transport parameters was analyzed by studying cubic subsamples from the images. The results indicate that both porosity and lacunarity are significant factors influencing the reactive transport parameters. However, neither parameter alone adequately characterizes their evolution. In contrast, combining them accurately characterizes the evolution of reactive transport parameters. Porosity reflects pore quantity, while lacunarity represents pore heterogeneity. Combining these measures facilitates a comprehensive understanding of the evolution of reactive transport parameters and the influence of pore microstructure on macroscopic reactive transport parameters. This research provides valuable insights for optimizing the leaching process in sandstone uranium ore deposits.

在砂岩铀矿床的原地沥滤过程中，包括渗透率、迂回度和比表面积（SSA）在内的反应性迁移参数的动态演变在溶液流动和溶质迁移中起着至关重要的作用。确定这些参数的演变特征对于了解沥滤过程至关重要。然而，砂岩的异质孔隙结构使得仅靠孔隙度不足以捕捉这些参数的变化。本研究将孔隙度和裂隙度结合起来，以全面描述这些参数的特征。为此，对砂岩铀矿石样本进行了浸出实验，并在不同浸出时间点进行了 CT 成像。通过研究图像中的立方体子样本，分析了反应传输参数的演变。结果表明，孔隙度和裂隙度都是影响反应迁移参数的重要因素。然而，这两个参数都不能单独充分描述其演变特征。相反，将这两个参数结合起来，就能准确地描述反应输运参数的演变。孔隙度反映孔隙数量，而裂隙度则代表孔隙异质性。将这些指标结合起来，有助于全面了解反应输运参数的演变以及孔隙微观结构对宏观反应输运参数的影响。这项研究为优化砂岩铀矿床的浸出过程提供了宝贵的见解。

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引用次数: 0

Social acceptance of small modular reactor (SMR): Evidence from a contingent valuation study in South Korea 小型模块化反应堆（SMR）的社会接受度：来自韩国或有估值研究的证据

IF 2.7 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-07-30 DOI: 10.1016/j.net.2024.07.059

Eunjung Cho, Juyong Lee

This study provides a comprehensive analysis of the social acceptance of the Small Modular Reactor (SMR) in South Korea. The growing interest in SMRs as a potential solution to the challenges of climate change and energy security highlights the need for continued research and development in this area. The research was conducted using a contingent valuation method, which involved surveying a representative sample of the South Korean population. Out of a total of 1032 respondents, 78 % were willing to pay for SMR development. The mean WTP was estimated to be USD 4.28 per year per household and scaled up to the national level in South Korea, it was analysed to have a total economic and social benefit of USD 0.49 billion. The more serious the respondents perceived the current and future problem of climate change to be, the more likely they were to be willing to pay an offered bid amount. This study suggests that the need to address climate change and the need to raise awareness of SMR as one of the low-carbon technologies at the government level is required to generate the appropriate level of social acceptance to promote SMR development.

本研究全面分析了韩国社会对小型模块化反应堆（SMR）的接受程度。人们对小型模块化反应堆作为应对气候变化和能源安全挑战的潜在解决方案的兴趣与日俱增，这凸显了在这一领域继续开展研究和开发的必要性。研究采用或然估值法，对韩国具有代表性的人口进行抽样调查。在总共 1032 名受访者中，78% 的人愿意为 SMR 的开发付费。据估计，每个家庭每年的平均 WTP 为 4.28 美元，按韩国全国水平计算，其经济和社会效益总额为 4.9 亿美元。受访者认为当前和未来的气候变化问题越严重，他们就越有可能愿意支付出价。这项研究表明，需要在政府层面应对气候变化并提高人们对 SMR 作为低碳技术之一的认识，以产生适当的社会认可度，促进 SMR 的发展。

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引用次数: 0

The effect of zinc, iron and manganese content on gamma shielding properties of magnesium-based alloys produced using the powder metallurgy 锌、铁和锰含量对粉末冶金法生产的镁基合金伽马屏蔽性能的影响

IF 2.6 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-07-25 DOI: 10.1016/j.net.2024.07.039

Mesut Ramazan Ekici , Emre Tabar , Gamze Hoşgör , Emrah Bulut , Ahmet Atasoy

This study investigates the effects of Zinc (Zn), Manganese (Mn), and Iron (Fe) additions on the microstructure, corrosion behaviour, biocompatibility, mechanical, and gamma-ray shielding properties of Magnesium (Mg) alloys prepared in various compositions using powder metallurgy (PM). The microstructure and mechanical properties of these alloys were analyzed using electron microscopes (SEM and FE-SEM) and X-ray diffraction (XRD) methods. The results showed positive changes in the material's structure when the percentage of zinc added to pure magnesium increased. It was observed that the material became ductile, and the ductile fracture increased when the zinc ratio increased. The gamma-ray shielding properties of newly produced Mg-based alloys have also been discussed since they have a high potential for use in space technologies. Radiation shielding measurements have been performed using a 3′′ × 3″ NaI(Tl) scintillation detector NaI (Tl) gamma-ray spectrometer. The gamma-ray shielding parameters such as the linear attenuation coefficients (μ_l), mass attenuation coefficient (μ_m), effective atomic number (Z_eff), half-value layer (HVL), and tenth-value layer (TVL) have been determined experimentally at photon energies of 0.511 MeV (emitted from a²²Na radioactive point source) and 1.173 MeV and 1.332 MeV (emitting from a⁶⁰Co radioactive point source). The obtained parameters have been compared to the theoretical results of the XCOM software, and a satisfactory agreement has been found. It can be said from the results that the Mg30Zn alloy has the best shielding properties among the produced materials.

本研究探讨了锌 (Zn)、锰 (Mn) 和铁 (Fe) 的添加对使用粉末冶金法 (PM) 制备的各种成分的镁 (Mg) 合金的微观结构、腐蚀行为、生物相容性、机械性能和伽马射线屏蔽性能的影响。使用电子显微镜（SEM 和 FE-SEM）和 X 射线衍射（XRD）方法分析了这些合金的微观结构和机械性能。结果表明，当纯镁中添加的锌比例增加时，材料的结构发生了积极变化。据观察，当锌的比例增加时，材料变得有延展性，延展性断裂增加。还讨论了新生产的镁基合金的伽马射线屏蔽特性，因为它们在空间技术中的应用潜力很大。使用 3′′ × 3″ NaI（Tl）闪烁探测器 NaI（Tl）伽马射线光谱仪进行了辐射屏蔽测量。伽马射线屏蔽参数，如线性衰减系数（μl）、质量衰减系数（μm）、有效原子序数（Zeff）、半值层（HVL）和十值层（TVL），是在光子能量为 0.511 MeV（由 22Na放射性点源发射）、1.173 MeV 和 1.332 MeV（由 60Co 放射性点源发射）时通过实验测定的。获得的参数与 XCOM 软件的理论结果进行了比较，结果令人满意。从结果可以看出，Mg30Zn 合金在所生产的材料中具有最好的屏蔽性能。

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引用次数: 0

Leveraging physics-informed neural computing for transport simulations of nuclear fusion plasmas 利用物理信息神经计算进行核聚变等离子体的传输模拟

IF 2.6 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-07-25 DOI: 10.1016/j.net.2024.07.048

J. Seo, I.H. Kim, H. Nam

For decades, plasma transport simulations in tokamaks have used the finite difference method (FDM), a relatively simple scheme to solve the transport equations, a coupled set of time-dependent partial differential equations. In this FDM approach, typically over

O (1 0^{5})

time steps are needed for a single discharge, to mitigate numerical instabilities induced by stiff transport coefficients. It requires significant computing time as costly transport models are repeatedly called in a serial manner, proportional to the number of time steps. Additionally, the unidirectional calculations of FDM make it difficult to predict regions prior to the initial condition or apply additional temporal constraints. In this study, we discuss using a new scheme to solve plasma transport based on physics-informed neural networks (PINNs). PINN iteratively updates a function that maps spatiotemporal coordinates to plasma states, gradually reducing errors in transport equations. The required number of updates in PINNs is several orders of magnitude less than the chronological iterations in FDM. Furthermore, it is free from numerical instabilities arising from finite grids and enables more versatile semi-predictive simulations with arbitrary spatiotemporal constraints. In this paper, we discuss the features and potentials of the tokamak transport solver using PINNs through comparisons with FDM, and also its drawbacks and challenges.

几十年来，托卡马克中的等离子体输运模拟一直使用有限差分法（FDM），这是一种相对简单的方案，用于求解输运方程（一组耦合的时变偏微分方程）。在这种有限差分法中，单次放电通常需要超过 O(105) 个时间步长，以缓解僵化传输系数引起的数值不稳定性。这需要大量的计算时间，因为需要以串行方式反复调用昂贵的传输模型，其数量与时间步数成正比。此外，FDM 的单向计算很难预测初始条件之前的区域或应用额外的时间约束。在本研究中，我们讨论了使用基于物理信息神经网络（PINN）的新方案来解决等离子体传输问题。PINN 通过迭代更新将时空坐标映射到等离子体状态的函数，逐步减少传输方程中的误差。PINN 所需的更新次数比 FDM 中的按时间顺序迭代少几个数量级。此外，它不受有限网格引起的数值不稳定性的影响，可以在任意时空约束条件下进行更多用途的半预测模拟。本文通过与 FDM 的比较，讨论了使用 PINN 的托卡马克输运求解器的特点和潜力，以及其缺点和挑战。

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引用次数: 0

Uranium quantification in radioactive waste drums using In-Situ Object Counting System (ISOCS) for safeguards purposes 利用原位物体计数系统（ISOCS）对放射性废物桶中的铀进行定量，以达到保障目的

IF 2.6 3区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY

Nuclear Engineering and Technology

Pub Date : 2024-07-25 DOI: 10.1016/j.net.2024.07.040

Jihyun Ahn , Seungmin Lee , Hee Seo

For the peaceful use of nuclear energy, materials, and technology, various methods have been developed for safeguards purposes. Among them, the In-Situ Object Counting System has demonstrated its usefulness and reliability in various nuclear material verification activities, due to its capability of operating without standard materials. In the present study, the performance of In-Situ Object Counting System for uranium quantification was evaluated using an experimental drum at KEPCO NF as well as low-level radioactive waste drums at the Korea Radioactive Waste Agency. The results showed that In-Situ Object Counting System could quantify uranium in radioactive waste drums, with a relative error ranging from −1 to −67 % compared with destructive assay results. This study also examined, using the Monte Carlo N-particle transport 6.2 code, the factors that affect uncertainty in uranium quantification: geometrical conditions, spectrum quality, heterogeneity, and the self-shielding effect. These findings could prove useful in efforts to optimize the In-Situ Object Counting System as a tool for nuclear material verification in the safeguards context.

为和平利用核能、核材料和核技术，已开发出各种保障方法。其中，原位物体计数系统由于能够在没有标准材料的情况下运行，已在各种核材料核查活动中证明了其实用性和可靠性。在本研究中，利用韩国电力公司 NF 的一个实验桶以及韩国放射性废物管理局的低放射性废物桶，对原位物体计数系统在铀定量方面的性能进行了评估。结果表明，原位物体计数系统可以对放射性废物桶中的铀进行定量，与破坏性化验结果相比，相对误差在 -1% 到 -67% 之间。这项研究还使用蒙特卡洛 N 粒子传输 6.2 代码研究了影响铀定量不确定性的因素：几何条件、光谱质量、异质性和自屏蔽效应。这些研究结果可能有助于优化原位物体计数系统，使其成为保障监督背景下核材料核查的工具。

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引用次数: 0