Validating the simulation of beam-ion charge exchange in MAST Upgrade

IF 2.1 2区物理与天体物理 Q2 PHYSICS, FLUIDS & PLASMAS

Plasma Physics and Controlled Fusion Pub Date : 2023-12-14 DOI:10.1088/1361-6587/ad15ed

P. Ollus, Scott Allan, James R Harrison, Andrew R Jackson, T. Kurki-Suonio, K. G. McClements, Clive A Michael, David Moulton, B. Patel, Michael Robson, A. Snicker, J. Varje, Charles Vincent

{"title":"Validating the simulation of beam-ion charge exchange in MAST Upgrade","authors":"P. Ollus, Scott Allan, James R Harrison, Andrew R Jackson, T. Kurki-Suonio, K. G. McClements, Clive A Michael, David Moulton, B. Patel, Michael Robson, A. Snicker, J. Varje, Charles Vincent","doi":"10.1088/1361-6587/ad15ed","DOIUrl":null,"url":null,"abstract":"\n Simulation of the impact of charge-exchange (CX) reactions on beam ions in the MAST Upgrade spherical tokamak was compared to measurements carried out with a fission chamber (neutron fluxes) and a Fast Ion Deuterium-Alpha (FIDA) diagnostic. A simple model was developed to reconstruct the outer-midplane neutral density based on measurements of deuterium-alpha emission from edge neutrals, and on Thomson scattering measurements of electron density and temperature. The main computational tools used were the ASCOT orbit-following code and the FIDASIM code for producing synthetic FIDA signals. The neutral density reconstruction agrees qualitatively with SOLPS-ITER modelling and yields a synthetic passive FIDA signal that is consistent with measurement. When CX losses of beam ions are accounted for, predicted neutron emission rates are quantitatively more consistent with measurement. It was necessary to account for CX losses of beam ions in simulations to reproduce the measured passive FIDA signal quantitatively and qualitatively. The results suggest that the neutral density reconstruction is a good approximation, that CX with edge neutrals causes significant beam-ion losses in MAST Upgrade, typically 20% of beam power, and that the ASCOT fast-ion CX model can be used to accurately predict the redistribution and loss of beam ions due to CX.","PeriodicalId":20239,"journal":{"name":"Plasma Physics and Controlled Fusion","volume":"23 1","pages":""},"PeriodicalIF":2.1000,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasma Physics and Controlled Fusion","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1088/1361-6587/ad15ed","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, FLUIDS & PLASMAS","Score":null,"Total":0}

引用次数: 0

Abstract

Simulation of the impact of charge-exchange (CX) reactions on beam ions in the MAST Upgrade spherical tokamak was compared to measurements carried out with a fission chamber (neutron fluxes) and a Fast Ion Deuterium-Alpha (FIDA) diagnostic. A simple model was developed to reconstruct the outer-midplane neutral density based on measurements of deuterium-alpha emission from edge neutrals, and on Thomson scattering measurements of electron density and temperature. The main computational tools used were the ASCOT orbit-following code and the FIDASIM code for producing synthetic FIDA signals. The neutral density reconstruction agrees qualitatively with SOLPS-ITER modelling and yields a synthetic passive FIDA signal that is consistent with measurement. When CX losses of beam ions are accounted for, predicted neutron emission rates are quantitatively more consistent with measurement. It was necessary to account for CX losses of beam ions in simulations to reproduce the measured passive FIDA signal quantitatively and qualitatively. The results suggest that the neutral density reconstruction is a good approximation, that CX with edge neutrals causes significant beam-ion losses in MAST Upgrade, typically 20% of beam power, and that the ASCOT fast-ion CX model can be used to accurately predict the redistribution and loss of beam ions due to CX.

查看原文本刊更多论文

验证 MAST 升级中的束离子电荷交换模拟

模拟了电荷交换（CX）反应对 MAST 升级版球形托卡马克中束离子的影响，并将其与使用裂变室（中子通量）和快速离子氘-阿尔法（FIDA）诊断仪进行的测量结果进行了比较。根据对边缘中子氘-阿尔法发射的测量结果，以及对电子密度和温度的汤姆逊散射测量结果，建立了一个简单的模型来重建外-中平面中子密度。使用的主要计算工具是 ASCOT 轨道跟踪代码和用于产生合成 FIDA 信号的 FIDASIM 代码。中性密度重建与 SOLPS-ITER 建模在质量上一致，并产生了与测量结果一致的合成被动 FIDA 信号。如果考虑束离子的 CX 损失，预测的中子发射率在数量上与测量结果更加一致。有必要在模拟中考虑束离子的 CX 损失，以便定量和定性地再现测量到的被动 FIDA 信号。结果表明，中子密度重构是一个很好的近似值，边缘中子的 CX 会在 MAST 升级中造成大量束离子损失，通常为束功率的 20%，ASCOT 快速离子 CX 模型可用于准确预测 CX 造成的束离子再分布和损失。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Plasma Physics and Controlled Fusion 物理-物理：核物理

CiteScore

4.50

自引率

13.60%

发文量

224

审稿时长

4.5 months

期刊介绍： Plasma Physics and Controlled Fusion covers all aspects of the physics of hot, highly ionised plasmas. This includes results of current experimental and theoretical research on all aspects of the physics of high-temperature plasmas and of controlled nuclear fusion, including the basic phenomena in highly-ionised gases in the laboratory, in the ionosphere and in space, in magnetic-confinement and inertial-confinement fusion as well as related diagnostic methods. Papers with a technological emphasis, for example in such topics as plasma control, fusion technology and diagnostics, are welcomed when the plasma physics is an integral part of the paper or when the technology is unique to plasma applications or new to the field of plasma physics. Papers on dusty plasma physics are welcome when there is a clear relevance to fusion.