Fusion Engineering and Design最新文献

{"title":"An interpretable isoflux-based observer for plasma shape control errors in tokamaks","authors":"Alessandro Tenaglia, Federico Pesamosca, Federico Felici, Daniele Carnevale, Stefano Coda, Adriano Mele, Antoine Merle","doi":"10.1016/j.fusengdes.2024.114618","DOIUrl":"https://doi.org/10.1016/j.fusengdes.2024.114618","url":null,"abstract":"In tokamaks, plasma shape control is often achieved through a so-called approach that regulates the poloidal flux differences between a reference point and a set of control points and magnetic field values at suitable locations to obtain the desired shape. Despite its simplicity, this approach presents two primary drawbacks: first, a method is needed to translate desired shape modifications, , radial or vertical shifts, into variations of the poloidal flux and magnetic field references; second, interpreting controller performance metrics may not be straightforward, since control errors are expressed in terms of physical quantities, , flux differences, magnetic fields, that cannot be directly related to positional errors. In this work, we propose a comprehensive methodology to establish relationships that link variations of poloidal flux and magnetic field values concerning a nominal plasma equilibrium in a predefined set of shape control points to local deformations of the Last Closed Flux Surface (LCFS). The effectiveness of this approach is demonstrated on the Tokamak à Configuration Variable (TCV) model through extensive simulations that consider various plasma configurations and shape modifications.","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"9 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222976","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":"First operation of LLMHD loop with electromagnet for R & D MHD experiments","authors":"A. Patel ,&nbsp;S. Verma ,&nbsp;A. Saraswat ,&nbsp;P. Satyamurthy ,&nbsp;S. Malhotra ,&nbsp;R. Bhattacharyay ,&nbsp;S. Gupta ,&nbsp;A. Prajapati ,&nbsp;M. Kumar ,&nbsp;T.S. Rao ,&nbsp;A. Makwana ,&nbsp;D. Sharma ,&nbsp;A. Jaiswal ,&nbsp;D. Mohanta ,&nbsp;S.K. Sharma ,&nbsp;V. Vasava ,&nbsp;H. Tailor ,&nbsp;A. Deoghar ,&nbsp;S. Sahu ,&nbsp;C. Dodiya ,&nbsp;S. Ranjith Kumar","doi":"10.1016/j.fusengdes.2024.114614","DOIUrl":"10.1016/j.fusengdes.2024.114614","url":null,"abstract":"<div><p>The Liquid Lead lithium Magneto Hydro Dynamics (LLMHD) experimental facility has been constructed at Institute for Plasma Research (IPR), Gujarat, India to perform various R &amp; D MHD experiments associated with the flow of electrically conducting liquid metal under strong transverse magnetic field. The electromagnet having C-shaped soft iron core has been designed and developed, to provide a uniform magnetic field of up to 1.4T within its polar volume 1000 mm (H) ×400 mm (W) ×370 mm (L). The magnetic field lines are aligned along the length (L). A relatively large polar volume inside the electromagnet to place the test mock up for MHD experiments is its particularity. It enables the study of MHD flows with complex flow geometries and having longer flow length perpendicular to the magnetic field. We have started running the LLMHD loop and the first MHD experiments with Pb-Li have been performed so far at 320 °C in a test mock-up of a basic circular flow geometry having two 90° bends. So far till now, the isothermal MHD experiments have been conducted in the presence of a uniform transverse magnetic field of 0.62T (Ha ∼ 322) and 1.06T (Ha∼551) for the ranges of Reynolds number 20,000–50,000. During the MHD experiments, flow rates, temperature, pressure, and induced wall electric potential have been recorded. The MHD effects on the pressure drop and flow rate has been noticed. The 3D MHD numerical simulation has also been performed, using add on MHD module of ANSYS FLUENT. Both simulation and experimental results of the induced wall electric potential have been compared.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"207 ","pages":"Article 114614"},"PeriodicalIF":1.9,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945843","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":"Nonlinear control of the minimum safety factor in tokamaks by optimal allocation of spatially moving electron cyclotron current drive","authors":"Sai Tej Paruchuri ,&nbsp;Andres Pajares ,&nbsp;Tariq Rafiq ,&nbsp;Eugenio Schuster","doi":"10.1016/j.fusengdes.2024.114612","DOIUrl":"10.1016/j.fusengdes.2024.114612","url":null,"abstract":"<div><p>The minimum value of the safety factor profile is related to the magnetohydrodynamic (MHD) stability of the plasma confined in a tokamak. Therefore, active control of the minimum safety factor may mitigate MHD instabilities that can degrade or even terminate plasma confinement. Typically, in most tokamak scenarios, the minimum safety factor evolves spatially with time, i.e., the location at which the safety factor achieves the minimum value changes with time. In addition to the inherent nonlinearities in the minimum safety factor evolution, its spatial variation makes the control design challenging. In particular, complexity in control design may arise from the need for time-dependent nonlinear models that account for spatial variation of the minimum safety factor. Furthermore, the minimum safety factor may drift to locations where the actuator authority is low. The problem of minimum safety factor control with target location tracking and moving electron cyclotron current drive (ECCD) is addressed in this work. A nonlinear time-dependent model that incorporates the spatial variation of the minimum safety factor is presented. A nonlinear controller based on optimal feedback linearization is developed to track a target minimum safety factor. The proposed controller treats the ECCD position as a controllable variable. In other words, the controller prescribes the ECCD position (in addition to the non-inductive powers) in real time based on an optimal criterion that is defined a priori. This work also presents the steps necessary to integrate the minimum safety factor controller with a total energy controller to achieve multiple control objectives simultaneously. The proposed integrated control algorithm is tested using nonlinear simulations in the Control Oriented Transport SIMulator (COTSIM) for a DIII-D tokamak scenario.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"207 ","pages":"Article 114612"},"PeriodicalIF":1.9,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945840","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":"Pre-conceptual design and proof of principle assessments of self-cooled Toroidally symmetric lead-lithium (TSLL) blanket","authors":"Sergey Smolentsev,&nbsp;Sunday Aduloju,&nbsp;Jin Whan Bae,&nbsp;Yuqiao Fan,&nbsp;Paul Humrickhouse","doi":"10.1016/j.fusengdes.2024.114617","DOIUrl":"10.1016/j.fusengdes.2024.114617","url":null,"abstract":"<div><p>A new self-cooled liquid metal blanket concept called TSLL (Toroidally Symmetric Lead-Lithium) blanket is proposed and assessed, including analysis for magnetohydrodynamic (MHD) flows, structural analysis, and heat transfer and neutronics assessments using the ARC reactor with demountable magnets designed by the Commonwealth Fusion Systems (CFS) as a testbed. The proposed blanket utilizes lead-lithium (PbLi) alloy as breeder/coolant and reduced activation ferritic/martensitic (RAFM) steel as structural material. A special feature of the new concept is the toroidally symmetric flow in the blanket integrated first wall and the breeding zone to reduce the MHD pressure drop, while using anchor links to strengthen the first wall construction. Provided analysis suggests acceptable MHD pressure drop, required mechanical integrity and high tritium breeding ratio of ∼ 1.64. As a result of these assessments, the new blanket concept can be recommended for more detailed studies as a promising blanket candidate for implementation in future fusion devices.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"207 ","pages":"Article 114617"},"PeriodicalIF":1.9,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945842","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":"Designing and Simulating an additive manufacturable liquid metal heat pipe for future fusion application","authors":"M. Bakker ,&nbsp;N. Maassen ,&nbsp;L. Kaserer","doi":"10.1016/j.fusengdes.2024.114611","DOIUrl":"10.1016/j.fusengdes.2024.114611","url":null,"abstract":"<div><p>The feasibility of a radiatively cooled 3D-printable liquid metal heat pipe (HP) design is assessed. Using the design flexibility offered by 3D-printing, the design of the wick and geometry of the HP were optimised to meet the requirement of 20 <span><math><mrow><mi>MW</mi><mo>/</mo><msup><mrow><mi>m</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> heat load for a HP placed in a 1.5 T magnetic field. COMSOL was used to assess the operational limits of the HP, the thermal stresses in the wall, the thermally radiated power, and various materials for the HP. The main parameters are the diameter and spacing of the screen wires and the emissivity, 200 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span>, 200 <span><math><mrow><mi>μ</mi><mi>m</mi></mrow></math></span> and 0.86 respectively. Molybdenum was chosen as the wall material and lithium as the working fluid. The design was made in Siemens NX and then exported to COMSOL. From simulations it was concluded that a molybdenum HP with the final design was capable of handling a steady state heat load of 20 <span><math><mrow><mi>MW</mi><mo>/</mo><msup><mrow><mi>m</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span>.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"207 ","pages":"Article 114611"},"PeriodicalIF":1.9,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0920379624004629/pdfft?md5=7f7f66bbc91f4193b04cdfd244128ba9&pid=1-s2.0-S0920379624004629-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Optimal control of the electron temperature profile in DIII-D using machine learning surrogate models","authors":"Shira Morosohk ,&nbsp;Zibo Wang ,&nbsp;Sai Tej Paruchuri ,&nbsp;Tariq Rafiq ,&nbsp;Eugenio Schuster","doi":"10.1016/j.fusengdes.2024.114615","DOIUrl":"10.1016/j.fusengdes.2024.114615","url":null,"abstract":"<div><p>The viability of the tokamak as a potential fusion reactor depends on the ability to keep the plasma in a stable regime while achieving temperatures, densities, and confinement times that are as high as possible. Tokamak scenario development attempts to find plasma regimes that achieve all of these conditions and are accessible with a given set of hardware constraints. This requires the ability to control plasma properties such as the normalized beta, the internal inductance, safety factor, rotation, etc. One property that has received less attention than some of the others, but is no less critical to achieving high performance, is the electron temperature (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span>) profile. In this work, Linear Quadratic Integral (LQI) control is used to develop a controller for the electron temperature profile in DIII-D. The controller is based on a linearized model derived from the transport equation that describes the evolution of the electron temperature, and includes contributions from the neural network surrogate models NubeamNet and MMMnet. The controller is tested in simulation using COTSIM, and is proven capable of tracking a target <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> profile.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"206 ","pages":"Article 114615"},"PeriodicalIF":1.9,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945717","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":"Dynamic simulation of ITER cryo-distribution system using Aspen HYSYS","authors":"Vinit Shukla ,&nbsp;Hitensinh Vaghela ,&nbsp;Pratik Patel ,&nbsp;Jotirmoy Das ,&nbsp;Hyun-Sik Chang ,&nbsp;Srinivasa Muralidhara ,&nbsp;Cursan Marie ,&nbsp;David Grillot","doi":"10.1016/j.fusengdes.2024.114616","DOIUrl":"10.1016/j.fusengdes.2024.114616","url":null,"abstract":"<div><p>The ITER cryogenic system consists of the Liquid Helium (LHe) plant, the Cryo-Distribution (CD) system, and the cryo-lines. The Auxiliary Cold Boxes (ACBs) dedicated to cooling the superconducting (SC) magnet system and the Cryoplant Termination Cold Box (CTCB) of the ITER CD system are in the factory acceptance phase. The internal components of ACBs, <em>e.g.</em>, cryogenic valves, a cold compressor (CCp), heat exchangers, and a cold circulator (CCr), have been sized and assembled, ensuring their functionality. The interdependency of the functional parameters of one component over the others needs to be assessed, as their integrated performance under the dynamic heat load deposition from the SC magnets may impact the overall operation of the ITER cryogenic system. The ACBs are equipped with two helium baths having ∼ 1200 kg of He inventory and situated inside the Tokamak building. These baths act as a thermal buffer for the LHe plant, situated in the cryoplant building, allowing it to operate at a quasi-steady state despite heat load variation from the applications. Such a large helium inventory can challenge the secondary confinement system of ITER due to helium ingress accidental events and thus needs to be optimized. The integrated system-level simulation is therefore necessary for the safe and reliable operation of the cryogenic system under such demanding requirements. The present study summarizes the results obtained for ACBs dedicated to the magnet system, including CTCB for the enhanced ITER operation modes, and confirms the integrated performance of the system. The results show that the LHe baths inside the ACBs can be used as a thermal buffer with the proposed limit of initial filling and by keeping a constant opening of the respective J-T valves upstream of the LHe baths. The study outcome and the proposed recommendations would be beneficial to mitigate the pulsed heat load to the LHe plant while minimizing the helium inventory.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"206 ","pages":"Article 114616"},"PeriodicalIF":1.9,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945845","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 design of the external rotational transform coil on the J-TEXT tokamak","authors":"Yangbo Li ,&nbsp;Bo Rao ,&nbsp;Feiyue Mao ,&nbsp;Song Zhou ,&nbsp;Keze Li ,&nbsp;Chuanxu Zhao ,&nbsp;Zhengkang Ren ,&nbsp;Da Li ,&nbsp;Zhuo Huang ,&nbsp;Ying He ,&nbsp;Bo Hu ,&nbsp;Jie Huang ,&nbsp;Nengchao Wang ,&nbsp;Zhonghe Jiang ,&nbsp;Yonghua Ding ,&nbsp;Yasuhiro Suzuki ,&nbsp;the J-TEXT Team","doi":"10.1016/j.fusengdes.2024.114591","DOIUrl":"10.1016/j.fusengdes.2024.114591","url":null,"abstract":"<div><p>To explore innovative approaches for optimizing tokamak configurations and combining the advantages of both tokamaks and stellarators, the J-TEXT tokamak recently underwent an upgrade by installing the External Rotational Transform (ERT) coil system. This system consists of two rings for producing a helical magnetic field. Due to space limitations, the ERT coil system is installed inside the vacuum vessel. The ERT coils feature a modular rail structure designed to navigate the intricate vacuum vessel environment. The successful installation of the ERT coil system on J-TEXT has yielded preliminary experimental results that align with the design objectives.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"206 ","pages":"Article 114591"},"PeriodicalIF":1.9,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945849","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 hydraulic analysis of in-vessel loss of coolant accident for the EAST lower divertor primary heat transfer system","authors":"Jinxuan Zhou ,&nbsp;Jiansheng Hu ,&nbsp;Bin Guo ,&nbsp;Lei Yang ,&nbsp;Weibao Li","doi":"10.1016/j.fusengdes.2024.114613","DOIUrl":"10.1016/j.fusengdes.2024.114613","url":null,"abstract":"<div><p>Uneven heat load distribution on the divertor during the high power long-pluse discharge of the Experimental Advanced Superconducting Tokamak (EAST) leads to hot spot phenomena, potentially causing the Plasma Facing Component (PFC) material melting, flaking, and even penetration, which may trigger the in-vessel loss of coolant accident (LOCA). Continuous coolant intrusion could damage vacuum equipment, while flash evaporation may increase vacuum pressure, posing a potential threat to the safety of the device operation. In this research, the RELAP5/MOD3.4 program was employed to develope a model of the lower divertor primary heat transfer system (PHTS). Steady state analysis was conducted to obtain the key parameters of the system in comparison with the design parameters, and the results showed good consistency. Thermal-hydraulic analysis of the in-vessel LOCA is performed based on the design condition, quantitatively investigating the evolution of the breach discharge flow rate and vacuum pressure. An additional pneumatic isolation valve and check valve are proposed as an accident mitigation scheme, and the effectiveness is evaluated to provide a reference for the upgrade of EAST lower divertor PHTS.</p></div>","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"206 ","pages":"Article 114613"},"PeriodicalIF":1.9,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945846","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":"Corrigendum to “Total Ionizing Dose Estimation of ITER Upper Port Remote Handling Equipment” [Fusion Engineering and Design volume 202 (2024) 114359]","authors":"Shanshuang Shi ,&nbsp;Chang-Hwan Choi ,&nbsp;Taku Yokoyama ,&nbsp;Hongtao Pan ,&nbsp;A.J. López-Revelles ,&nbsp;P. Martínez-Albertos ,&nbsp;M. De Pietri ,&nbsp;G. Pedroche ,&nbsp;A. Kolšek ,&nbsp;R. Juarez","doi":"10.1016/j.fusengdes.2024.114604","DOIUrl":"10.1016/j.fusengdes.2024.114604","url":null,"abstract":"","PeriodicalId":55133,"journal":{"name":"Fusion Engineering and Design","volume":"206 ","pages":"Article 114604"},"PeriodicalIF":1.9,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0920379624004551/pdfft?md5=5c57fdb47ea2238c9f9a820bf07f4405&pid=1-s2.0-S0920379624004551-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141991348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}