Fusion Engineering and Design最新文献

{"title":"Evaluation of first wall charged particle heat load considering connection length in EU DEMO: A benchmarking analysis using PFCFlux and APPLE codes","authors":"Weixi Chen ,&nbsp;Shota Sugiyama ,&nbsp;Yoshiteru Sakamoto ,&nbsp;Francesco Maviglia ,&nbsp;Jonathan Gerardin","doi":"10.1016/j.fusengdes.2025.115124","DOIUrl":"10.1016/j.fusengdes.2025.115124","url":null,"abstract":"<div><div>Charged particle heat load simulation codes have been developed with three-dimensional magnetic field line tracing to estimate the heat loads on plasma facing components, based on the assumption that the heat flux in the scrape-off layer (SOL) decays exponentially. One of these codes, PFCFlux, has been used to calculate the heat flux on the EU DEMO first wall (FW). In this code, the outboard mid-plane (OMP) is used to define the area magnetically wetted by the plasma, assuming no heat flux on field lines that do not pass through the OMP. There have been concerns that the exclusion of these magnetic field lines means that the heat fluxes along these are not considered in the result. To address this, APple Peel Like Element (APPLE) code was introduced, which incorporates the length of the magnetic field line intersected with the FW, known as the connection length (CL), into the calculation. The evaluation for the CL effect was conducted in two steps: inter-code benchmarking between the two codes and switching the CL effect in the APPLE code for comparison. The benchmarking demonstrated a high degree of similarity between the codes. The comparison revealed that the changes in the charged particle heat load distribution are non-negligible in the simulation with large decay length, such as those involving divertor configuration.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115124"},"PeriodicalIF":1.9,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supercapacitor bank design for the DTT Central Solenoid power supplies","authors":"S. Pipolo ,&nbsp;A. Lampasi ,&nbsp;C. Terlizzi ,&nbsp;R. Testa","doi":"10.1016/j.fusengdes.2025.115074","DOIUrl":"10.1016/j.fusengdes.2025.115074","url":null,"abstract":"<div><div>The Divertor Tokamak Test (DTT) facility introduces several novel solutions to overcome the constraints of the present fusion power supply technologies. One of the main novelties consists in using supercapacitor banks to store and recover most of the energy required to supply the coils. This can reduce the energy drawn from the grid and the dimensions of the upstream equipment. The available energy could also be employed to stabilize the electrical network and to improve its power quality. Since supercapacitor-based energy storage could require even tens of thousands of commercial cells, the identification of its optimal design combined with the related converters is critical to control costs, dimensions, and power demand. This problem has been addressed through analytical models, simulations, and a heuristic algorithm, with thermal verification performed as part of the design process. The presented procedure is used to optimize the energy storage of the power supplies for the DTT central solenoid. By leveraging the characteristics of the expected operating scenarios, the grid input power for a demand of 150 MW is limited to 2.4 MW for all CS power supplies.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115074"},"PeriodicalIF":1.9,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of mini-flat and cylindrical test specimens to extract hardening law and ductility of neutron irradiated Eurofer97","authors":"Chih-Cheng Chang ,&nbsp;Dmitry Terentyev ,&nbsp;Alexander Bakaev ,&nbsp;Aleksandr Zinovev ,&nbsp;Daniele Del Serra ,&nbsp;Patricia Verleysen ,&nbsp;Thomas Pardoen","doi":"10.1016/j.fusengdes.2025.115072","DOIUrl":"10.1016/j.fusengdes.2025.115072","url":null,"abstract":"<div><div>Tensile properties such as strength and ductility are essential for structural integrity assessment of critical components. In the context of nuclear applications, the flat tensile geometry as compared to the reference standard cylindrical geometry offers a number of advantages in terms of material use efficiency, ease of machining, best packing under irradiation and simplified remote handling of active samples. Accordingly, the interchangeability of data extracted from flat and cylindrical specimens is a key issue. Furthermore, this interchangeability must be demonstrated for irradiated samples. Many metallic materials show significant reduction or even a full lack of uniform elongation after neutron irradiation, with most of the strain hardening regime taking place during the post-necking stage. As the necking development depends on geometry, this raises questions on the validity of changing the test specimen geometry. Here, the interchangeability of mini-flat and cylindrical tensile samples after neutron irradiation is investigated by combining experimental and computational analysis. The investigated material is EUROFER97 steel irradiated at 300 °C in the conditions relevant for the ITER fusion reactor. Finite element (FE) simulations are performed with a Gurson-type ductile fracture model parameterized based on the experimental tensile response. The hardening law extracted from mini-flat samples and applied to predict the stress-strain response of a cylindrical sample with 90 % accuracy or better in terms of total elongation, reduction of area, and fracture strength as compared to the direct experimental data obtained with cylindrical tensile specimen geometry.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115072"},"PeriodicalIF":1.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Progresses in the development of the tritium extraction and removal system for the water-cooled lithium-lead breeding blanket in EUROfusion","authors":"Alessandro Venturini ,&nbsp;Francesca Papa ,&nbsp;Ciro Alberghi ,&nbsp;Daniele Martelli ,&nbsp;Roberto Bonifetto ,&nbsp;Antonio Froio ,&nbsp;Fabrizio Lisanti ,&nbsp;Belit Garcinuño ,&nbsp;Fernando R. Urgorri ,&nbsp;Iván Fernández-Berceruelo ,&nbsp;Guillermo G. Fonfría ,&nbsp;Michal Kordac ,&nbsp;Ladislav Vála ,&nbsp;Adéla Gottfriedová ,&nbsp;Rocco Mozzillo ,&nbsp;Vincenzo Claps ,&nbsp;Eduardo Garciadiego-Ortega ,&nbsp;Hannah Askill","doi":"10.1016/j.fusengdes.2025.115126","DOIUrl":"10.1016/j.fusengdes.2025.115126","url":null,"abstract":"<div><div>In the EU DEMO reactor, the Water-Cooled Lithium-Lead Tritium Extraction and Removal system (WCLL TER) is dedicated to transporting tritium-rich PbLi from the Breeding Blanket to the Tritium Extraction Unit and then back to it, after tritium is extracted and routed to the fuel cycle. In addition to circulating PbLi and extracting tritium, the TER system maintains constant PbLi temperature of 330 °C, provides safe storage of PbLi during reactor shutdowns as well as PbLi purification from by-products and contaminants linked both to structural materials corrosion processes and neutronic reactions of Pb, Li and other dissolved species. This contribution presents the latest developments in the design of the WCLL TER and in some of the related key areas of research. Among the most significant outcomes, the Permeator Against Vacuum was selected as a reference tritium extraction technology, preferred over the Gas-Liquid Contactor and the Liquid Vacuum Contactor, and its design was updated based on recent experimental evidence. All components of the TER such as tanks, pipelines, valves and other equipment were integrated into the tokamak building, ensuring compliance with fundamental operating principles.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115126"},"PeriodicalIF":1.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering evaluation of the upgrade KSTAR divertor system","authors":"Sungjin Kwon ,&nbsp;Soo-Hyeon Park ,&nbsp;Hong-Tack Kim ,&nbsp;Yong Bok Chang ,&nbsp;Nak Hyong Song ,&nbsp;Sang Woo Kwag ,&nbsp;Hyung Ho Lee ,&nbsp;Jong Man Lee ,&nbsp;Hwnag Rae Cho ,&nbsp;Do Yoon Kim ,&nbsp;Hyeongseok Seo ,&nbsp;Soocheol Shin ,&nbsp;Sangmin Kim ,&nbsp;Junyoung Jeong ,&nbsp;Henri Greuner ,&nbsp;Bernd Boeswirth","doi":"10.1016/j.fusengdes.2025.115100","DOIUrl":"10.1016/j.fusengdes.2025.115100","url":null,"abstract":"<div><div>KSTAR (Korea Superconducting Tokamak Advanced Research) plans to upgrade the external heating power to 24 MW by improving heating systems such as NBI, ECH, ICRF, and so on. The upgrade divertor system should guarantee resistance to high heat flux and cooling capacity for the exhausting power in the scrape-off layer domain. The activity for the upgrade of the KSTAR divertor was initiated in 2019, and the upgrade divertor was successfully manufactured and installed in October 2023.The upgraded KSTAR divertor system employs the water-cooled tungsten monoblock, ITER-like divertor type. Tungsten is the most robust and promising plasma-facing material under high heat flux plasma circumstances, and the combination of CuCrZr heat sink and pressurized water coolant is the effective cooling method. The upgraded KSTAR divertor system has a single null configuration and 64 cassette divertor modules placed at the bottom of the vacuum vessel. A divertor module consists of the inner target, the central target, the outer target, and the cassette body, with supports to connect each part. CFD analysis was carried out in the previous study to confirm the thermal stability of a whole divertor module. The result showed the design could be operated within a thermal allowable range in 10 MW/m² heat flux. The temperature distribution from CFD analysis is applied to the thermo-mechanical analysis. Based on the ASME code, the upgrade KSTAR divertor was estimated for plastic collapse, ratcheting, fatigue, and buckling. The result showed the upgraded KSTAR divertor is reliable from the thermal and mechanical points of view. In the KSTAR divertor, tungsten monoblocks were used only in the straight section due to space constraints. However, in anticipation of a new Korean fusion device following KSTAR, we also explored the production technology for a divertor target that includes a curved section. While the hot isostatic pressing (HIP) process was utilized for dissimilar metal bonding in the KSTAR divertor, we applied the hot radial pressing (HRP) process for manufacturing the curved section target to diversify our production methods. A small mock-up sample of the curved section, manufactured using the HIP and HRP, underwent testing for 20 MW/m² during 1,000 high-heat flux tests. Both the HIP and HRP samples were completed without any issues. The result confirms the design and quality of the KSTAR divertor target were reliable enough to withstand the heat load, although the recrystallization of tungsten occurred.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115100"},"PeriodicalIF":1.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radio frequency wall conditioning discharges in argon atmosphere at Uragan-2 M stellarator","authors":"Yu.V. Kovtun ,&nbsp;A.V. Lozin ,&nbsp;V.E. Moiseenko ,&nbsp;M.M. Kozulya ,&nbsp;A.N. Shapoval ,&nbsp;R.O. Pavlichenko ,&nbsp;V.N. Bondarenko ,&nbsp;D.I. Baron ,&nbsp;S.M. Maznichenko ,&nbsp;V.B. Korovin ,&nbsp;E.D. Kramskoy ,&nbsp;A.Yu. Krasiuk ,&nbsp;V.S. Romanov ,&nbsp;Yu.P. Martseniuk ,&nbsp;I.E. Garkusha ,&nbsp;S. Brezinsek ,&nbsp;A. Dinklage ,&nbsp;the Uragan-2 M Team","doi":"10.1016/j.fusengdes.2025.115131","DOIUrl":"10.1016/j.fusengdes.2025.115131","url":null,"abstract":"<div><div>Two scenarios of radio frequency wall conditioning (RFWC) in the argon atmosphere at low magnetic field were investigated at Uragan-2 M stellarator. In the first scenario, a stellarator magnetic field is used to confine plasma of a RFWC discharge. In the second scenario RFWC discharge was realised in pure toroidal magnetic field. The plasma parameters were measured for different values of neutral gas pressure and RF power. In the RFWC discharge, the average plasma density up to ∼ 1 × 10¹⁸ <em>m</em>⁻³ was observed. Plasma ion composition and charges states were identified using the optical emission spectroscopy. The partial pressures of residual gases in the vacuum chamber were measured with a mass-spectrometer during series of the wall conditioning discharges. Measurements showed a decrease in water partial pressure of ∼ 50–51 % after the wall conditioning procedure for both scenarios.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115131"},"PeriodicalIF":1.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Density regulation with disruption avoidance in next-generation tokamaks using a safe reinforcement learning-based controller","authors":"Sai Tej Paruchuri ,&nbsp;Ian Ward ,&nbsp;Nicholas Rist ,&nbsp;Vincent Graber ,&nbsp;Hassan Al Khawaldeh ,&nbsp;Zibo Wang ,&nbsp;Eugenio Schuster ,&nbsp;Andres Pajares ,&nbsp;June-Woo Juhn","doi":"10.1016/j.fusengdes.2025.115064","DOIUrl":"10.1016/j.fusengdes.2025.115064","url":null,"abstract":"<div><div>Achieving high particle density is desirable in fusion reactors because of its direct correlation to the fusion power. However, operational limits constrain the maximum achievable particle density. Several density control algorithms have been designed to inject particles using gas puffing and pellet injection to track carefully selected safe targets. However, a controller unaware of these operational limits may modulate the particle densities beyond the safe limits during transients caused by changing operating conditions. Designing plasma control algorithms that recognize these operational limits and ensure that the particle density remains within the safe operational space is desirable. This work focuses on the safe regulation of deuterium–tritium (DT) particle density. Under the assumption of quasi-neutrality, the total plasma density can be related to the electron density, which is constrained by the well-known Greenwald limit. To regulate the DT density within the safe operational space defined by Greenwald limit, a novel safe reinforcement learning-based controller is developed in this work. Such control-design approach can be critical in designing learning-based safe plasma control algorithms for next-generation tokamaks. The effectiveness of the controller is demonstrated through nonlinear simulations conducted over multiple test cases.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115064"},"PeriodicalIF":1.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of non-steady state operation of a PEM electrolyzer on hydrogen isotope separation in a CECE process","authors":"O. Balteanu,&nbsp;A. Bornea,&nbsp;I. Ștefan,&nbsp;I. Făurescu,&nbsp;G. Ana,&nbsp;C. Bucur,&nbsp;M. Zamfirache","doi":"10.1016/j.fusengdes.2025.115127","DOIUrl":"10.1016/j.fusengdes.2025.115127","url":null,"abstract":"<div><div>The electrolyzer is one of the main components of the Combined Electrolysis and Catalytic Exchange (CECE) process used to provide isotopic enrichment of hydrogen. The CECE process demands that the electrolyzer run under constant operating parameters (mainly the flowrate and water hold-up). The influence of the non-steady state regime for an electrolyzer equipped with a proton exchange membrane (PEM) stack cell, has been investigated, considering variations of the water hold-up, induced by the water management in the cathode and anode circuits. Based on a mathematical model written for a constant hold-up, a new mathematical model was developed to simulate the tritium enrichment, considering different variation of the hold-up between two limits determined from experimental data. Tests with tritiated water were carried out to evaluate the influence of the electrolyzer’s water hold-up variation on the isotopic separation process and to verify the mathematical model.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115127"},"PeriodicalIF":1.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on signal measurement algorithm of circular dot matrix high current sensor","authors":"Xu Wu ,&nbsp;Haihong Huang ,&nbsp;Sheng Dou ,&nbsp;Lan Peng","doi":"10.1016/j.fusengdes.2025.115056","DOIUrl":"10.1016/j.fusengdes.2025.115056","url":null,"abstract":"<div><div>In the field of current measurement of nuclear fusion devices, dot matrix high current sensors are widely used because of their advantages of high precision, light weight, wide range and low cost. According to the magnetic field generated by the measured conductor in the circular dot matrix current sensor ring and the Ampere's circuital law, the current value of the measured conductor can be deduced, so as to realize the non-contact current measurement. Because the Ampere's circuital law adopts the line integral equivalent of discrete points, when there are other energized conductors around the measured conductor, the crosstalk field will cause significant measurement errors. In order to solve this problem, a signal processing algorithm should be considered to improve the measurement accuracy and practicability. The effect of the traditional numerical average algorithm is limited by the number of Hall elements, and the convergence factor is difficult to be determined due to the contradiction between the convergence speed and steady state error of the adaptive Least Mean Square (LMS) algorithm. Based on the ideas of the two algorithms mentioned above, this article proposes the wavelet analysis - Kalman algorithm. This algorithm utilizes the known system model and noise statistical characteristics combined with signal estimation and correction to obtain the optimal algorithm parameters, which can further reduce the measurement error of dot matrix current sensor and improve the adaptability of the sensor to the environment. According to the results of simulation and experimental verification, it is concluded that the wavelet analysis - Kalman algorithm is the best among the three algorithms, which can well suppress the influence of crosstalk field and random noise on the measurement results, and greatly improve the measurement accuracy of the sensor.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115056"},"PeriodicalIF":1.9,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143879113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal studies of liquid tin capillary porous system at the OLMAT high heat flux facility","authors":"M. Reji ,&nbsp;E. Oyarzábal ,&nbsp;A. de Castro","doi":"10.1016/j.fusengdes.2025.115013","DOIUrl":"10.1016/j.fusengdes.2025.115013","url":null,"abstract":"<div><div>Extreme heat and particle fluxes at the divertor tiles of a fusion device present one of the most critical challenges in achieving sustainable fusion energy. Solid plasma-facing components (PFCs) typically suffer from cracking, erosion, and melting, particularly during transient events, limiting their durability and effectiveness. In contrast, liquid metal PFCs may offer several advantages over their solid counterparts, primarily through their intrinsic resistance to permanent damage and the ability to dissipate heat via multiple channels, thereby enhancing the resilience and longevity of PFCs. This work investigates the thermal behaviour of a liquid tin (Sn) capillary porous system (CPS) target exposed to a high-energy particle beam at the OLMAT high heat flux (HHF) facility. To obtain accurate temperature measurements of the target, an iterative calibration method was developed, accounting for the metallization of the diagnostic window due to the shot-by-shot deposition of eroded Sn, an effect that partially affected the measurements.</div></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"216 ","pages":"Article 115013"},"PeriodicalIF":1.9,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}