M. Bugatti, L. Bana, D. Vavassori, M. Iafrati, D. Dellasega, M. Passoni
{"title":"Progress in the Development of a W-based Corrosion Barrier for ENEA Liquid Sn-based Divertor Design","authors":"M. Bugatti, L. Bana, D. Vavassori, M. Iafrati, D. Dellasega, M. Passoni","doi":"10.1007/s10894-025-00503-5","DOIUrl":"10.1007/s10894-025-00503-5","url":null,"abstract":"<div><p>Experimental research was conducted to develop a corrosion barrier for protecting the copper-chromium-zirconium (CuCrZr) and stainless steel components of future liquid tin divertors. W-based coatings with tailored properties were deposited on planar metallic samples by high power impulse magnetron sputtering (HiPIMS), optimizing the deposition parameters to enhance mechanical properties and improve corrosion resistance. A validation experimental campaign was carried out based on conditions expected in the ENEA liquid metal divertor design. To identify the highest-performing coating, coated samples were exposed to a static droplet of liquid tin at <span>(400,^{circ })</span>C for up to 600 min, followed by post-mortem characterization. The results indicate that tin corrosion is significantly less concerning towards steel and can be effectively prevented under these operating conditions through the developed coatings. On CuCrZr substrates, pure-W coatings demonstrated insufficient corrosion protection and reliability issues, leading to mechanical failure of the barrier. The experiments underlined the importance of substrate preparation and surface defects on corrosion barrier properties. In contrast, W-Al coatings were able to successfully and reliably prevent liquid tin corrosion, indicating that low-crystallinity and amorphous materials are more suitable as corrosion barriers for liquid tin divertor applications.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10894-025-00503-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144861442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"In Memoriam: Professor Yoshi Hirooka (1953–2025)–A Founding Visionary of Liquid Metals for Fusion","authors":"Guizhong Zuo","doi":"10.1007/s10894-025-00507-1","DOIUrl":"10.1007/s10894-025-00507-1","url":null,"abstract":"","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Novel Unsupervised Gated Recurrent Neural Network for Plasma Disruption Prediction in Aditya Tokamak Using Dynamic Threshold-Based Temporal Differentiation","authors":"Priyanka Muruganandham, Sangeetha Jayaraman, Sivanesan Perumal, Kumudni Tahiliani, Rakesh Tanna, Joydeep Ghosh, Nilam Ramaiya, Aditya-U Team","doi":"10.1007/s10894-025-00506-2","DOIUrl":"10.1007/s10894-025-00506-2","url":null,"abstract":"<div><p>Plasma disruption prediction is essential for sustaining stable nuclear fusion reactions. Existing data-driven approaches face limitations due to their dependence on labeled datasets, which are often difficult to curate in dynamic plasma environments. Also, these models typically rely on setting a fixed threshold—a manually defined cutoff point to detect fluctuations in plasma current that may indicate an impending disruption. This threshold is manually defined and remains constant, which can make it ineffective under evolving plasma conditions, where the nature of fluctuations may change over time. To address the limitations, this study proposes an unsupervised Gated Recurrent Neural Network model with a Dynamic Threshold-based Temporal Differentiation Algorithm (GRNN-DTTD) to predict disruptions. This threshold is formed by continuously analyzing temporal variations in plasma current fluctuations, allowing it to adjust based on evolving signal patterns. This adaptive mechanism enables the GRNN-DTTD to detect abnormal trends associated with impending disruptions without the need for pre-labeled training data. By learning directly from variations in the input signals over time, the model operates in an unsupervised manner, which identifies disruptive patterns and issues early warnings. Experimental evaluation was conducted on Aditya dataset (133 training shots, 91 unseen testing shots) which demonstrates the model’s effectiveness by achieving 98.9% prediction accuracy with warning times of 12–30 ms prior to disruption events. The results show that the proposed framework avoids manual threshold setting, eliminates dependency on labeled data, and improves adaptability to changing plasma conditions.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tritium Transport Model at the Breeder Module Level for a Water-Cooled Ceramic Breeder Blanket for the CFETR","authors":"Xueli Zhao, Baoliang Zhang, Shuai Chen, Wanhuan Yang, Weihua Zhong","doi":"10.1007/s10894-025-00508-0","DOIUrl":"10.1007/s10894-025-00508-0","url":null,"abstract":"<div><p>The tritium self-sufficiency concept has been pursued with the development of fusion energy, which requires tritium treatment and recovery. Accordingly, the tritium transport characteristics in a breeder blanket are crucial to predict the tritium inventories and permeation. In the present work, a multiphysics coupling analysis model for a water-cooled ceramic breeder (WCCB) blanket was built, providing a method to conduct a comprehensive assessment of the tritium transport behaviors in the blanket, including the tritium concentration, tritium inventory, and tritium permeation through the structural material to the coolant. Bulk diffusion and surface processing of tritium in the blanket are considered, and the isotope exchange reaction in the purge gas and the effect of the hydrogen content on the tritium transport behavior are also considered. These results indicate that hydrogen plays a significant role in reducing the tritium inventory and permeation.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Monte Carlo Evaluations of Displacement and Ion Range Values on Ti-6Al-4 V Fusion Structural Alloy by Aneutronic Fusion Reactions","authors":"Hatun Korkut, Turgay Korkut","doi":"10.1007/s10894-025-00502-6","DOIUrl":"10.1007/s10894-025-00502-6","url":null,"abstract":"<div><p>Studies on energy production based on approaches based on nuclear fusion reactions that do not produce neutron emissions have recently gained momentum. In this study, the interactions between the particles emitted from the neutron-free fusion (or aneutronic fusion) reactions of <sup>3</sup>He(d, p)<sup>4</sup>He, <sup>6</sup>Li(d, α)<sup>4</sup>He, <sup>6</sup>Li(p, α)<sup>3</sup>He and <sup>11</sup>B(p, 2α)<sup>4</sup>He and Ti-6Al-4V alloy were modeled with SRIM, FLUKA and GEANT4 Monte Carlo simulation codes. Damage and penetrability parameters obtained from the simulations were evaluated. Evaluations were made on the most suitable aneutronic reaction for this alloy. It is thought that important outcomes have been obtained regarding fusion reactor structure and engineering.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hu Wang, Chao Fang, Zhengbao Yu, Yong Xiao, Shuangsong Du, Yinbin Lv, Jing Huang, Jin Liu, Aofeng Shi, Xiaoyu Dong, Jing Wei, Weihua Wang, Wei Lu, Xiaowu Yu
{"title":"Comparative Study of Epoxy-Wollastonite Composites and Sn55PbAgSb Solder for Helium Cooling Channels in Toroidal Field Coil Casings","authors":"Hu Wang, Chao Fang, Zhengbao Yu, Yong Xiao, Shuangsong Du, Yinbin Lv, Jing Huang, Jin Liu, Aofeng Shi, Xiaoyu Dong, Jing Wei, Weihua Wang, Wei Lu, Xiaowu Yu","doi":"10.1007/s10894-025-00501-7","DOIUrl":"10.1007/s10894-025-00501-7","url":null,"abstract":"<div><p>To address the thermal management challenges under extreme operational conditions of tokamak toroidal field (TF) magnets, this study systematically compared the cryogenic performance of epoxy-wollastonite composites (EWC) implemented in ITER and Sn<sub>55</sub>PbAgSb solder (SPAS) applied in EAST for helium cooling channels, based on the Comprehensive Research Facility for Fusion Technology (CRAFT) TF coil casing. Through finite element heat transfer modeling at 4.2 K with heat flux ranging from 1 W/m²to 30 W/m², the results demonstrate that cooling channels fabricated with SPAS solder exhibit a 2.12–5.32% reduction in the average cold-side temperature (<i>T</i><sub>cs</sub>) compared to EWC, with the performance gap narrowing to 0.23% at ultra-low heat flux conditions (1 W/m²). The mechanical testing under 77 K cryogenic conditions demonstrates superior crush resistance in EWC (no defects at 400 kN) compared to solder-based counterparts (crack initiation observed at 200 kN). The findings establish a material selection protocol: SPAS is optimal for high heat flux regions to enhance thermal dissipation, while EWC is preferred in mechanically critical zones to ensure structural integrity. These results offer actionable engineering guidelines, balancing thermal efficiency and mechanical robustness for future fusion reactors.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145143790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"JxB-Forced Convection Effects on the Heat and Particles Transport in Liquid Li and GaInSn Under Steady State Plasma Bombardment","authors":"Yoshi Hirooka","doi":"10.1007/s10894-025-00497-0","DOIUrl":"10.1007/s10894-025-00497-0","url":null,"abstract":"<div><p>It has widely been recognized that the particle control and heat removal capabilities of plasma-facing components (PFCs) such as divertor will affect the overall performance of a steady-state magnetic fusion power reactor. The existing divertor technologies developed for ITER with a heating power of ~ 100 MW may not readily allow us to expect the successful operation of DEMO reactors often with a heating power of > 500 WM if the P (heating power)/R (major radius) ratio scaling law by Kotschenreuther is applied, details of which will be described in this paper. Over the past several decades, a variety of innovative PFC concepts have been proposed to resolve these divertor issues. Conducted in the present work are proof-of-principle experiments on one of these innovative PFC concepts, employing a liquid metal as the plasma-facing material with the particular emphasis on the effects of forced liquid convection on heat and particle transport, both observed simultaneously.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145171015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of Applicability of Geant4 and OpenMC in Tritium Breeding Calculation for Fusion Blanket","authors":"Shiteng Zhang, Haibing Guo, Jimin Ma, Jingyu Sun","doi":"10.1007/s10894-025-00500-8","DOIUrl":"10.1007/s10894-025-00500-8","url":null,"abstract":"<div><p>Tritium breeding calculation is a crucial aspect of fusion blanket design. Currently, the typical particle transport code MCNP is extensively utilized in tritium breeding research, though the distribution of its new version is strictly restricted. The open-source Monte Carlo particle transport code Geant4 and OpenMC are regarded as possible substitutes, but their accuracy in tritium breeding calculation for fusion blanket has not been verified sufficiently. In this paper, we evaluated the suitability of Geant4 and OpenMC for tritium breeding calculation based on experimental data and the MCNP results, focusing on two types of blanket mock-ups and a novel blanket made of spent nuclear fuel. The results indicate that both Geant4 and OpenMC are suitable for tritium breeding calculations, though the overall deviation in Geant4 is slightly larger. OpenMC has better pertinence and ease of use for neutron transport problems and smaller TBR deviation. However, discrepancies are observed in the calculation of fission nuclide reaction rates for the spent nuclear fuel blanket.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145171016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preparation of Millimeter-Sized Li2TiO3 Ceramic Pebbles by Droplet Microfluidics and UV Curing","authors":"Xin Hu, Guangfan Tan, Liang Cai, Biao Yi, Dajun Xu, Zeyu Gao, Xiaoxu Dong, Yusha Li, Yingchun Zhang","doi":"10.1007/s10894-025-00498-z","DOIUrl":"10.1007/s10894-025-00498-z","url":null,"abstract":"<div><p>In order to meet the huge demand for millimetre-sized Li<sub>2</sub>TiO<sub>3</sub> ceramic pebbles for future fusion reactors, the aim of this work was to develop a combination of microfluidic and UV curing techniques to greatly improve the preparation efficiency. By employing a cross-junction microfluidic device, large-sized droplets were controllably generated and subsequently subjected to in-situ UV curing, enabling rapid solidification of resin-based ceramic slurries. Systematic investigations revealed critical processing parameters: (1) The rheological behavior of ceramic slurries was governed by solid content and dispersant concentration, directly influencing droplet stability during microfluidic manipulation. (2) UV curing efficacy depended on exposure time(10 ~ 40 s), aging time (30 ~ 120 s) and solid content, and the optimised conditions allow complete cross-linking of 2 mm green pebbles. (3) Post-sintering at an ultra-low heating rate (0.5 °C/min) produced Li<sub>2</sub>TiO<sub>3</sub> ceramic pebbles with a relatively dense microstructure and high crush load(42 N).This microfluidic and UV curing strategy demonstrates potential process controllability and scalability.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucas Spangher, Matteo Bonotto, William Arnold, Dhruva Chayapathy, Tommaso Gallingani, Alexander Spangher, Francesco Cannarile, Daniele Bigoni, Eliana de Marchi, Cristina Rea
{"title":"DisruptionBench and Complimentary New Models: Two Advancements in Machine Learning Driven Disruption Prediction","authors":"Lucas Spangher, Matteo Bonotto, William Arnold, Dhruva Chayapathy, Tommaso Gallingani, Alexander Spangher, Francesco Cannarile, Daniele Bigoni, Eliana de Marchi, Cristina Rea","doi":"10.1007/s10894-025-00495-2","DOIUrl":"10.1007/s10894-025-00495-2","url":null,"abstract":"<div><p>Plasma disruptions remain a major obstacle to sustained commercial operation of tokamak-based fusion devices. Although machine learning (ML) methods have shown promise for predicting disruptions, their performance and generalizability suffer from a lack of common benchmarks and comprehensive multi-device evaluations. To address this, we present <b>DisruptionBench</b>, a new benchmarking platform designed to standardize how ML-driven disruption prediction systems are trained and evaluated on multi-machine data. DisruptionBench spans three devices - Alcator C-Mod, DIII-D, and EAST - and includes tasks of varying difficulty: zero-shot, few-shot, and many-shot training regimes to assess each model’s ability to transfer learned representations to new or data-limited machines. We evaluate four state-of-the-art ML architectures. Two are re-implementations of notable prior work: a random forest (Cristina Rea in PPCF 60:084008, 2018) and the Hybrid Deep Learner (HDL) (Zhu in NC 61: 026607, 2020). We also propose two new approaches tailored for disruption prediction: a transformer-based model inspired by GPT-2, capable of learning long-range temporal dependencies through self-attention, and a Continuous Convolutional Neural Network (CCNN) that leverages continuous kernels to capture subtle variations in plasma signals. Across the nine benchmarking tasks, the CCNN demonstrates consistently strong performance and achieves the highest overall Area Under the ROC Curve (AUC) in intra-machine tests (up to 0.97 on C-Mod). Nevertheless, the GPT-2-based approach and HDL can outperform CCNN in specific transfer scenarios, particularly when the test machine is underrepresented in training data. We further analyze the significance of memory length in capturing precursor phenomena, providing evidence that longer context windows can boost predictive accuracy.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":"44 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10894-025-00495-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144131675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}