{"title":"Rotating flux-tube model for local gyrokinetic simulations with background flow and magnetic shears","authors":"Shinya Maeyama , Tomo-Hiko Watanabe , Motoki Nakata , Masanori Nunami , Yuuichi Asahi , Akihiro Ishizawa","doi":"10.1016/j.jcp.2024.113595","DOIUrl":null,"url":null,"abstract":"<div><div>We have developed a new computational method called the rotating flux-tube model that treats background shear flows in local gyrokinetic simulations. The method is based on extended magnetohydrodynamic ballooning mode theory. A coordinate transformation moves the flux-tube simulation domain along the sheared magnetic field lines, counteracting the deformation caused by the background shear flow. Linear analyses showed that the rotating flux-tube model describes the time-continuous evolution of fluctuations under shear flow as a single wavenumber mode. The formulation of the rotating flux-tube model makes explicit its mathematical correspondence to the Floquet theory. Nonlinear simulations demonstrated that the rotating flux-tube model can analyze the effects of background shear flow on turbulent transport.</div></div>","PeriodicalId":352,"journal":{"name":"Journal of Computational Physics","volume":"522 ","pages":"Article 113595"},"PeriodicalIF":3.8000,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Computational Physics","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S002199912400843X","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS","Score":null,"Total":0}
引用次数: 0
Abstract
We have developed a new computational method called the rotating flux-tube model that treats background shear flows in local gyrokinetic simulations. The method is based on extended magnetohydrodynamic ballooning mode theory. A coordinate transformation moves the flux-tube simulation domain along the sheared magnetic field lines, counteracting the deformation caused by the background shear flow. Linear analyses showed that the rotating flux-tube model describes the time-continuous evolution of fluctuations under shear flow as a single wavenumber mode. The formulation of the rotating flux-tube model makes explicit its mathematical correspondence to the Floquet theory. Nonlinear simulations demonstrated that the rotating flux-tube model can analyze the effects of background shear flow on turbulent transport.
期刊介绍:
Journal of Computational Physics thoroughly treats the computational aspects of physical problems, presenting techniques for the numerical solution of mathematical equations arising in all areas of physics. The journal seeks to emphasize methods that cross disciplinary boundaries.
The Journal of Computational Physics also publishes short notes of 4 pages or less (including figures, tables, and references but excluding title pages). Letters to the Editor commenting on articles already published in this Journal will also be considered. Neither notes nor letters should have an abstract.