Nuclear Engineering and Technology最新文献_第3页

Comparative study on thermal creep resistance of arc ion plated and magnetron sputtered Cr coatings on Zircaloy-4 cladding for accident tolerant fuel 耐事故燃料锆-4包层电弧离子镀和磁控溅射Cr涂层耐热蠕变性能的比较研究

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-22 DOI: 10.1016/j.net.2026.104148

Jong-Dae Hong , Hongryul Oh , Martin Ševeček , Hyochan Kim , Dong-Joo Kim , Sung Eun Kim

The development of accident tolerant fuel (ATF) claddings, particularly coating techniques, has been encouraged to address the urgent need for improved safety measures. Using the two prominent coating technologies—that is, arc ion plating (AIP) and magnetron sputtering (MS)—pure Cr was coated on Zry-4 claddings, and the effect of the Cr coating on low temperature (≤400 °C) creep behavior was investigated. Moreover, their mechanical performance was compared based on the coating method. Creep tests conducted using internal pressurization methods under constant hoop stresses revealed that the AIP Cr coatings reduced the total creep strain by approximately 43–60 %, whereas the MS Cr coatings exhibited an 18–33 % reduction. These improvements on the creep resistance were attributed to the high elastic modulus and limited plasticity of the Cr layer as well as the compressive residual stresses induced during the deposition process. However, ring compression tests (RCTs) performed after creep deformation showed that the residual ductility, characterized by offset strain, decreased in Cr-coated claddings, most notably in the MS Cr-coated specimens, owing to the intrinsic brittleness of the Cr layer. Experimental findings on thermal creep behaviors suggest that while Cr coatings significantly improved the creep resistance and delay gap closure, their mechanical integrity under irradiation and pellet-to-cladding mechanical interaction conditions must be carefully assessed to ensure long–term fuel performance in ATF systems.

已鼓励发展耐事故燃料包覆层，特别是包覆技术，以解决改进安全措施的迫切需要。采用电弧离子镀（AIP）和磁控溅射（MS）两种主要的涂层技术，在Zry-4包层上镀上纯Cr，并研究了Cr涂层对Zry-4包层低温（≤400℃）蠕变行为的影响。并基于涂层法对其力学性能进行了比较。在恒定环向应力下，采用内加压方法进行的蠕变试验表明，AIP Cr涂层可将总蠕变应变降低约43 - 60%，而MS Cr涂层则可降低18 - 33%。这些抗蠕变性能的提高是由于Cr层的高弹性模量和有限塑性以及沉积过程中产生的残余压应力。然而，在蠕变变形后进行的环压缩试验（rct）表明，由于Cr层的固有脆性，Cr包覆层的残余延展性（以偏应变为特征）下降，尤其是在MS Cr包覆试件中。热蠕变行为的实验结果表明，尽管Cr涂层显著提高了抗蠕变性能和延迟间隙闭合性，但必须仔细评估其在辐照和球团-包层力学相互作用条件下的机械完整性，以确保ATF系统中的长期燃料性能。

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引用次数: 0

An efficient Gauss-Seidel-based acceleration method for solving the MMPA burnup equation system in nuclear reactors 求解核反应堆MMPA燃耗方程系统的一种高效高斯-塞德尔加速方法

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-06 DOI: 10.1016/j.net.2026.104121

Yuqing Sun , Binhang Zhang , Hanyuan Gong , Changxiao Guan , Yonghong Zhang , Xianbao Yuan

Burnup calculation ensures the operational safety of nuclear reactors by determining the evolutionary behavior of radioactive nuclides through the solution of the burnup equations. The Mini-Max Polynomial Approximation (MMPA) method is an effective solution technique developed in recent years, and it offers several advantages over the Chebyshev Rational Approximation Method (CRAM). However, solving the MMPA system of equations using sparse Gaussian elimination (SGE) is computationally expensive because it involves repeated symbolic factorization, especially for large-scale problems. This study develops a Gauss-Seidel (GS)-based acceleration method, an iterative approach that avoids matrix preprocessing and reduces storage overhead by retaining only the necessary matrices and vectors. It offers fast convergence for diagonally dominant matrices. The method was rigorously implemented and verified through a light water reactor (LWR) pin-cell case, by utilizing three burnup databases containing the 71-, 221-, and 1487-nuclide inventories. The results obtained from all burnup databases indicate that once the approximation order exceeds 32, the average absolute relative difference of nuclide number densities reaches a magnitude of 10⁻¹⁰. The distribution of relative difference in nuclide number densities also becomes more concentrated and falls below 1.0 × 10⁻¹¹, confirming excellent computational accuracy. In terms of efficiency, the GS-based acceleration method outperforms the SGE method across the approximation order range of 32–48. For the 1487-nuclide database, the GS-based acceleration method achieves a runtime reduction of nearly 50 % compared to the SGE method. For computations involving the 221- and 71-nuclide databases, the GS-based acceleration method achieves a computational efficiency improvement of at least 70 %. This method provides an effective solution for enhancing the computational efficiency of burnup equations, which in turn contributes to improving the efficiency of large-scale burnup calculations.

燃耗计算通过求解燃耗方程来确定放射性核素的演化行为，从而保证核反应堆的运行安全。最小-最大多项式近似法（MMPA）是近年来发展起来的一种有效的求解方法，它与切比雪夫有理近似法（CRAM）相比具有许多优点。然而，使用稀疏高斯消去（SGE）求解MMPA方程组的计算成本很高，因为它涉及重复的符号分解，特别是对于大规模问题。本研究开发了一种基于Gauss-Seidel （GS）的加速方法，这是一种迭代方法，避免了矩阵预处理，并通过仅保留必要的矩阵和向量来减少存储开销。它提供了对角占优矩阵的快速收敛性。该方法在一个轻水反应堆（LWR）针槽案例中得到了严格的实施和验证，使用了包含71-、221-和1487-核素清单的三个燃用数据库。从所有燃用数据库得到的结果表明，一旦近似阶数超过32，核素数密度的平均绝对相对差达到10−10的量级。核素数密度的相对差分布也变得更加集中，降至1.0 × 10−11以下，证实了较好的计算精度。在效率方面，基于gs的加速方法在32-48阶近似范围内优于SGE方法。对于1487核素数据库，基于gs的加速方法与SGE方法相比，运行时间减少了近50%。对于涉及221和71核素数据库的计算，基于gs的加速方法实现了至少70%的计算效率提高。该方法为提高燃耗方程的计算效率提供了有效的解决方案，从而有助于提高大规模燃耗计算的效率。

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引用次数: 0

Study of the removal of Th(IV) and U(VI) from aqueous solutions using lemon charcoal 柠檬炭去除水溶液中Th（IV）和U（VI）的研究

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-06 DOI: 10.1016/j.net.2026.104124

Shrouq AlAzzeh, Fawwaz I. Khalili

This study evaluated the adsorption potential of lemon-derived charcoal for removing Th(IV) and U(VI) ions from aqueous solutions. The adsorbent was characterized using Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analysis, revealing a specific surface area of 123.65 m²/g and a pore volume of 0.468 cm³/g. Additional physicochemical properties, including point of zero charge, bulk density, porosity, and cation exchange capacity, were also determined. Optimal adsorption occurred at an adsorbent dose of 0.03 g, pH 4.0, and contact times of 20 min for Th(IV) and 60 min for U(VI). Kinetic studies indicated that adsorption followed the pseudo-second-order model for both ions. The equilibrium data were fitted to four isotherm models—Freundlich, Langmuir, Dubinin–Radushkevich, and Temkin—yielding maximum adsorption capacities (q_m) of 75.15 mg/g for Th(IV) at 25.0 °C and 44.26 mg/g for U(VI). Thermodynamic analysis (ΔH°, ΔS°, ΔG°) confirmed that the adsorption process was spontaneous and exothermic.

本研究评价了柠檬衍生炭对水中Th（IV）和U（VI）离子的吸附潜力。采用傅里叶变换红外光谱（FTIR）、热重分析（TGA）、粉末x射线衍射（P-XRD）、扫描电镜（SEM）和brunauer - emmet - teller （BET）表面积分析对该吸附剂进行了表征，其比表面积为123.65 m2/g，孔隙体积为0.468 cm3/g。其他物理化学性质，包括零电荷点、体积密度、孔隙度和阳离子交换容量也被确定。吸附剂剂量为0.03 g， pH为4.0,Th（IV）接触时间为20 min， U（VI）接触时间为60 min，吸附效果最佳。动力学研究表明，两种离子的吸附均符合准二级模型。平衡数据符合freundlich、Langmuir、Dubinin-Radushkevich和temkin四种等温模型，在25.0℃条件下，Th（IV）的最大吸附量为75.15 mg/g， U（VI）的最大吸附量为44.26 mg/g。热力学分析（ΔH°，ΔS°，ΔG°）证实吸附过程为自发的放热过程。

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引用次数: 0

Determination of 14C in radwaste samples through sequential wet oxidation and acid stripping extraction 序贯湿氧化-酸提法测定放射性废物样品中的14C

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-07 DOI: 10.1016/j.net.2026.104129

Feng-Yun J. Huang , Yi-Lun Chen , Tsuey-Lin Tsai , Chun-Yi Fang , Wan-Ling Chen , Ling-Ling Hsieh , Jiunn-Hsing Chao

¹⁴C is a long half-life nuclide (t_1/2 = 5730 y) produced naturally and artificially. It is a difficult-to-measure nuclide because of its pure beta decay, but identifying it is essential to ensuring appropriate radwaste disposal and management. This study developed and optimized a practical process for analyzing ¹⁴C from 21 radioactive waste samples. The measured activity of ¹⁴C in the radioactive waste samples ranged from 0.05 ± 0.04 to 68.83 ± 0.13 Bq g⁻¹, and their scaling factors (¹⁴C-to-⁶⁰Co activity ratio) were calculated to be 0.035–1.015. In summary, the developed simple and low-cost sequential wet-oxidation-acid-stripping extraction process can be routinely used for determining ¹⁴C in low-level radwaste samples in the laboratory.

14C是一种长半衰期的核素（t1/2 = 5730 y），自然和人工产生。由于其纯粹的β衰变，它是一种难以测量的核素，但识别它对于确保适当的放射性废物处理和管理至关重要。本研究开发并优化了从21个放射性废物样品中分析14C的实用过程。测得放射性废物样品中14C的活度范围为0.05±0.04 ~ 68.83±0.13 Bq g−1，其比例因子（14C / 60co活度比）为0.035 ~ 1.015。综上所述，所开发的简单、低成本的顺序湿式氧化-酸提萃取工艺可常规用于实验室低水平放射性废物样品中的14C测定。

引用次数: 0

Comparative study on neutronic characteristics of cylindrical and three-petal fuel rod 圆柱形和三瓣燃料棒中子特性的比较研究

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-06 DOI: 10.1016/j.net.2026.104120

Deping Du , Dabin Sun , Jincheng Wang , Xunjian Che , Jianchuang Sun , Weihua Cai

To make up for deficiencies in neutronics calculation of 3-Pl-shaped fuel rods (TPF), further determine neutron transport characteristics of TPF in conventional assemblies. This paper uses DGA-OpenMC to build neutronic calculation models for cylindrical and petal-shaped fuel assemblies (CFA and TPFA) under different

V_{H_{2} O} / V_{U}

. It compares influences of fuel rod types and

V_{H_{2} O} / V_{U}

on neutronic characteristics. Results show the following. First, when

V_{H_{2} O} / V_{U}

is within [3.18, 7.38], k_∞ of CFA is 1342 ± 40pcm to 2125 ± 40pcm higher than that of TPFA, and flux distribution of CFA is more uniform. Analysis of nuclear reaction rates finds that fission nuclear reaction rate of CFA is higher, while resonance absorption nuclear reaction rate of TPFA is higher. Second, when

V_{H_{2} O} / V_{U}

increases, neutron energy spectrum of assemblies softens, and uniformity of flux distribution decreases. Data shows that when water uranium ratio increases from 3.18 to 7.38, f_R of CFA and TPFA increase by 1.22 %.

为了弥补3- pl型燃料棒（TPF）中子电子学计算的不足，进一步确定常规组件中TPF的中子输运特性。本文利用DGA-OpenMC建立了圆柱形和花瓣形燃料组件（CFA和TPFA）在不同VH2O/VU下的中子计算模型。比较了燃料棒类型和VH2O/VU对中子特性的影响。结果显示如下。首先，当VH2O/VU在[3.18,7.38]范围内时，CFA的k∞比TPFA高1342±40pcm ~ 2125±40pcm，且CFA的通量分布更加均匀。核反应速率分析发现，CFA的裂变核反应速率更高，而TPFA的共振吸收核反应速率更高。当VH2O/VU增大时，组件中子能谱软化，通量分布均匀性降低。数据表明，当水铀比从3.18增加到7.38时，CFA和TPFA的fR增加了1.22%。

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引用次数: 0

Systematic investigation on neutronics and thermal-hydraulics model for multi-physics analysis of micro molten salt fast reactor with moderating reflector 带慢化反射镜的微熔盐快堆多物理场分析的中子学和热工力学模型的系统研究

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-03 DOI: 10.1016/j.net.2026.104114

Wooseong Park, Yong Hoon Jeong

A moderating reflector in Molten Salt Fast Reactors (MSFRs) enables dual‐spectrum core—combining advantages of both fast and thermal spectra—but introduces strong local power peaking and a positive reflector temperature coefficient (RTC), whose impacts in steady and transient states remain largely unexplored. To address the research gap, we systematically evaluated neutronics and thermal-hydraulics model effects on the multi-physics behavior of an MSFR with moderating reflector, using GeN-Foam and OpenMC. First, multi-group diffusion analysis with various multi-group cross section (MGXS) models was conducted, demonstrating that refined MGXS (30-group structure with multi-region spatial homogenization) model can provide reasonably accurate predictions for MSFR with moderating reflector. Next, the influences of different neutronics (N) and thermal-hydraulics (TH) models on steady-state multi-physics calculations were examined. The results show that explicit reflector region modeling in TH simulation, together with the refined MGXS model, is crucial for accurate multi-physics simulation. Finally, transient analysis of accident scenarios was performed to investigate the basic dynamic behavior of the system and to assess the impacts of the positive RTC and MGXS model. The results show that simple MGXS model exhibits delayed power response to negative temperature feedback, and that positive RTC effects are not significant over short-term periods.

熔盐快堆（MSFRs）中的慢化反射器能够实现双光谱堆芯——结合快光谱和热光谱的优势——但引入了强的局部功率峰值和正反射器温度系数（RTC），其对稳态和瞬态的影响在很大程度上仍未被探索。为了弥补研究空白，我们使用GeN-Foam和OpenMC系统地评估了中子力学和热工力学模型对带调节反射器的MSFR多物理场行为的影响。首先，利用不同的多组截面（multi-group cross section， MGXS）模型进行了多组扩散分析，结果表明，改进的MGXS（30组结构，多区域空间均匀化）模型能够较为准确地预测具有调节反射镜的MSFR。其次，研究了不同的中子模型(N)和热工模型（TH）对稳态多物理场计算的影响。结果表明，在TH模拟中，明确的反射区建模以及改进的MGXS模型对于精确的多物理场模拟至关重要。最后，进行了事故场景的瞬态分析，研究了系统的基本动态行为，并评估了正RTC和MGXS模型的影响。结果表明，简单MGXS模型对温度负反馈的功率响应延迟，且短期内正RTC效应不显著。

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引用次数: 0

Towards a strategic path for the Republic of Korea's nuclear energy policy: Insights for the next revision of the ROK-U.S. nuclear cooperation agreement 走向大韩民国核能政策的战略路径：对韩美合作协定下一次修订的见解。核能合作协议

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-05 DOI: 10.1016/j.net.2026.104117

Keonhee Lee , Eunju Jun

This paper examines a multifaceted strategic approach for Republic of Korea's future nuclear energy policy within the complex framework of the ROK-U.S. Nuclear Cooperation Agreement. This agreement serves as the core legal basis for extensive nuclear cooperation between the two nations, evolving from a supplier-consumer relationship to one aiming for mutual exercise of authority and reciprocity following its 2015 revision. However, the U.S. prior consent requirement continues to impose constraints on Korea's nuclear autonomy and technological sovereignty, particularly concerning sensitive nuclear activities such as spent fuel management and enrichment. This study explores the challenges faced by Korea through a comparative analysis of the differentiated prior consent practices applied by the U.S. to various partner countries. It seeks to derive strategic insights for reconciling Korea's energy needs and technological aspirations with U.S. nonproliferation and regional security objectives, while managing potential friction points within the alliance. Ultimately, by proposing a proactive and multifaceted strategic approach - including strengthening domestic research and development (R&D) capabilities, advancing diplomatic efforts, leveraging joint research outcomes, and enhancing Korea's responsible leadership in international nonproliferation - this paper aims to contribute to improving Korea's energy security and technological self-reliance within the framework of the ROK-U.S. alliance.

本文探讨了在韩美关系的复杂框架下，韩国未来核能政策的多方面战略方针。核能合作协定。该协议是两国广泛核合作的核心法律基础，在2015年修订后，从供应商-消费者关系演变为旨在相互行使权力和互惠的关系。然而，美国的事先同意要求继续限制韩国的核自主权和技术主权，特别是在乏燃料管理和浓缩等敏感核活动方面。本研究通过比较分析美国对各伙伴国实行的不同的事先同意惯例，探讨了韩国面临的挑战。它寻求获得战略见解，以协调韩国的能源需求和技术抱负与美国的防扩散和地区安全目标，同时管理联盟内部潜在的摩擦点。最终，通过提出一种积极主动的、多方面的战略方针——包括加强国内研发能力、推进外交努力、利用联合研究成果，以及加强韩国在国际防扩散方面负责任的领导地位——本文旨在为改善韩国的能源安全和在韩美安全框架内的技术自立做出贡献。联盟。

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引用次数: 0

The beamline optical component structural parameter optimization design based on PyAnsys and deep learning integration 基于PyAnsys和深度学习集成的光束线光学元件结构参数优化设计

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-15 DOI: 10.1016/j.net.2026.104142

Tong Li , Hao Zhou , Zhifeng Huang , Zhongmin Xu , Weiqing Zhang

With the rapid development of high-repetition rate X-ray free electron laser (FEL), the issues of thermal deformation and stress in optical elements, such as mirrors, under high thermal loads have become increasingly prominent. Traditional design optimization relies on repeated Thermal-Structural coupling finite element simulations, which face bottlenecks, including low optimization efficiency and insufficient utilization of historical data. This paper proposes an optimization approach that combines PyAnsys parametric scanning with deep learning-based surface shape prediction, aiming to enhance the optimization efficiency of mirror cooling structures and support parameters. A parametric simulation platform is constructed using PyAnsys Geometry and PyMechanical, enabling the rapid generation of model variants within 30 s. Additionally, a historical database containing geometric features, physical parameters, and operating conditions is established. Furthermore, a deep neural network-based mirror height error prediction model is developed, and experiments show that the model can predict surface height errors with RMS <0.08 nm in water-cooled silicon mirror cases. This method has the potential to shorten the traditional design iteration cycle to a few hours, significantly enhancing data reuse. Future work should focus on incorporating incremental learning and physical constraints to improve the reliability of extrapolation for multi-condition scenarios and refine the optimization loop.

随着高重复率x射线自由电子激光器（FEL）的快速发展，光学元件（如反射镜）在高热载荷下的热变形和热应力问题日益突出。传统的设计优化依赖于重复的热-结构耦合有限元模拟，存在优化效率低、历史数据利用率不足等瓶颈。本文提出了一种将PyAnsys参数扫描与基于深度学习的曲面形状预测相结合的优化方法，旨在提高镜面冷却结构和支撑参数的优化效率。利用PyAnsys Geometry和PyMechanical构建了参数化仿真平台，可在30s内快速生成模型变体。此外，还建立了包含几何特征、物理参数和操作条件的历史数据库。在此基础上，建立了基于深度神经网络的镜面高度误差预测模型，实验结果表明，该模型对水冷硅镜面的镜面高度误差预测的RMS为0.08 nm。这种方法有可能将传统的设计迭代周期缩短到几个小时，显著提高数据重用。未来的工作应侧重于将增量学习和物理约束结合起来，以提高多条件情景外推的可靠性，并完善优化循环。

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引用次数: 0

Experimental study on pressurized water reactor imaging using cosmic ray muons 宇宙射线介子在压水堆成像中的实验研究

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-13 DOI: 10.1016/j.net.2026.104133

Yupeng Li , Shengguo Wu , Xiaoke Wang , Jing Zheng , Yufei Wu , Xinnan Chen , Chunyu Gao , Chenyang Tang , Qiaoling Lu , Yang Liu , Xiuzhang Tang

This study presents cosmic-ray muon transmission imaging of a nuclear reactor. A high-spatial-resolution drift-tube muon tracker with an active area of 1.1 × 1.1 m² was deployed at Unit 1 of a commercial nuclear power plant in China, which is a "Hualong One" pressurized water reactor, and operated for six months to record muon flux from various directions. Prior to fuel loading, a two-dimensional absorption map of the reactor was reconstructed from coincident muon events, which clearly resolved the reactor core and surrounding structures. After fuel loading, measurable changes in the absorption signal were observed in the fuel region. Monte Carlo simulations yielded reactor and core-specific imaging results that were in good agreement with the experimental measurements. In addition, the impact of tracker spatial resolution on image quality was analyzed. These findings indicate that muon transmission imaging is a promising method for reactor imaging.

本研究提出核子反应炉的宇宙射线介子透射成像。在中国商用核电站“华龙一号”压水堆1号机组安装了高空间分辨率漂管型介子跟踪仪，有效面积为1.1 × 1.1 m2，运行了6个月，记录了不同方向的介子通量。在燃料加载前，利用同步μ子事件重建了反应堆的二维吸收图，清晰地分辨了反应堆堆芯和周围结构。加载燃料后，在燃料区观察到可测量的吸收信号变化。蒙特卡罗模拟产生的反应堆和堆芯特定成像结果与实验测量结果很好地一致。此外，分析了跟踪器空间分辨率对图像质量的影响。这些发现表明，μ子透射成像是一种很有前途的反应堆成像方法。

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引用次数: 0

EEMD analysis of unsteady pressure pulsations of a high-pressure reactor circulating pump under off-design working conditions 高压反应堆循环泵非定常压力脉动的EEMD分析

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

Nuclear Engineering and Technology

Pub Date : 2026-05-01 Epub Date: 2026-01-22 DOI: 10.1016/j.net.2026.104146

Ning Zhang , Jiaqing Chen , Hui Liu , Mona Gad , Bo Gao

High-pressure reactor circulating pumps are widely used in nuclear power systems to maintain the cooling circulation of reactors and serve as the primary loop pump. Rotating stall is likely to occur under low flow conditions, posing a risk to system stability and safety. In this study, the evolution of rotating stall under low flow conditions was investigated using DDES and high-frequency pressure pulsation measurements. The pressure pulsation spectra were analyzed through the improved EEMD. TKE and FEL were used to evaluate energy dissipation inside the pump. Results show that pressure pulsation energy increased rapidly under off-design conditions. At the critical stall condition (0.36Φ_N), the amplitude of f_BPF increased to three times its design value, and the RMS∗ value in the 0-f_R band nearly doubled. According to the EEMD results, the dominant mode IMF₇ has an instantaneous frequency consistent with f_BPF, during stall, with the low-frequency mode IMF₁₃ surging by 289 % under deep stall conditions. Intense turbulent pulsations are induced by the interaction between secondary backflow at the impeller outlet and main flow. Regions of high TKE and FEL are formed at the guide vane inlet and extend into the impeller channel, leading to significant energy dissipation. This is identified as the main cause of the increased amplitude of the f_BPF at the part load conditions. This study provides insights into a better understanding of pressure pulsations and complex flow structures of the impeller/diffuser matched reactor circulating pump.

高压反应堆循环泵广泛应用于核电系统中，是维持反应堆冷却循环的主回路泵。在低流量工况下容易发生旋转失速，对系统的稳定性和安全性构成威胁。在本研究中，采用DDES和高频压力脉动测量研究了低流量条件下旋转失速的演变。通过改进的EEMD分析了压力脉动谱。采用TKE和FEL对泵内能量耗散进行了评价。结果表明，在非设计工况下，压力脉动能量迅速增大。在临界失速状态下（0.36ΦN）， fBPF的幅值增加到设计值的3倍，0-fR波段的RMS∗值几乎增加了一倍。根据EEMD结果，在失速过程中，主导模式IMF7具有与fBPF一致的瞬时频率，而低频模式IMF13在深度失速条件下飙升289%。叶轮出口二次回流与主流的相互作用引起了强烈的湍流脉动。高TKE和FEL区域在导叶入口处形成并延伸到叶轮通道，导致显著的能量耗散。这被认为是部分载荷条件下fBPF振幅增加的主要原因。该研究有助于更好地理解叶轮/扩散器匹配反应器循环泵的压力脉动和复杂流动结构。

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引用次数: 0