{"title":"多尺度电子湍流的流动剪切失稳","authors":"E A Belli, J Candy, I Sfiligoi","doi":"10.1088/1361-6587/ad2c28","DOIUrl":null,"url":null,"abstract":"The impact of sheared <inline-formula>\n<tex-math><?CDATA ${\\mathbf{E} \\hskip -1pt \\times \\hskip -1pt \\mathbf{B}}$?></tex-math>\n<mml:math overflow=\"scroll\"><mml:mrow><mml:mrow><mml:mi mathvariant=\"bold\">E</mml:mi></mml:mrow><mml:mo>×</mml:mo><mml:mrow><mml:mi mathvariant=\"bold\">B</mml:mi></mml:mrow></mml:mrow></mml:math>\n<inline-graphic xlink:href=\"ppcfad2c28ieqn1.gif\" xlink:type=\"simple\"></inline-graphic>\n</inline-formula> flow on multiscale turbulence is studied with nonlinear gyrokinetic simulations. Simulations are based on DIII-D-like, high-confinement mode (H-mode) pedestal parameters in the regime of low ion temperature gradient drive, where there is a broad spectrum of electron temperature gradient (ETG)-driven turbulence. It is found that <inline-formula>\n<tex-math><?CDATA ${\\mathbf{E} \\hskip -1pt \\times \\hskip -1pt \\mathbf{B}}$?></tex-math>\n<mml:math overflow=\"scroll\"><mml:mrow><mml:mrow><mml:mi mathvariant=\"bold\">E</mml:mi></mml:mrow><mml:mo>×</mml:mo><mml:mrow><mml:mi mathvariant=\"bold\">B</mml:mi></mml:mrow></mml:mrow></mml:math>\n<inline-graphic xlink:href=\"ppcfad2c28ieqn2.gif\" xlink:type=\"simple\"></inline-graphic>\n</inline-formula> shear can have a significant effect on ETG-driven electron transport, with an unexpected transition from a turbulence stabilization regime at moderate to large shearing rates <italic toggle=\"yes\">γ</italic>\n<sub>\n<italic toggle=\"yes\">E</italic>\n</sub> to a novel turbulence destabilization regime at low levels of <italic toggle=\"yes\">γ</italic>\n<sub>\n<italic toggle=\"yes\">E</italic>\n</sub>. In the turbulence stabilization regime, the electron energy flux decreases monotonically with <italic toggle=\"yes\">γ</italic>\n<sub>\n<italic toggle=\"yes\">E</italic>\n</sub>, even when <italic toggle=\"yes\">γ</italic>\n<sub>\n<italic toggle=\"yes\">E</italic>\n</sub> is small compared to electron mode growth rates. The stabilizing effect comes dominantly from the electron, not ion, gyrokinetic equation. In the novel destabilization regime, reduction of zonal energy results from the interaction of <italic toggle=\"yes\">γ</italic>\n<sub>\n<italic toggle=\"yes\">E</italic>\n</sub>-modulated nonlinear drive in the zonal ion gyrokinetic equation, increasing the electron transport over a broad range of shearing rates. Neither of these effects have been observed in previous electron-scale simulations.","PeriodicalId":20239,"journal":{"name":"Plasma Physics and Controlled Fusion","volume":"40 1","pages":""},"PeriodicalIF":2.1000,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Flow-shear destabilization of multiscale electron turbulence\",\"authors\":\"E A Belli, J Candy, I Sfiligoi\",\"doi\":\"10.1088/1361-6587/ad2c28\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The impact of sheared <inline-formula>\\n<tex-math><?CDATA ${\\\\mathbf{E} \\\\hskip -1pt \\\\times \\\\hskip -1pt \\\\mathbf{B}}$?></tex-math>\\n<mml:math overflow=\\\"scroll\\\"><mml:mrow><mml:mrow><mml:mi mathvariant=\\\"bold\\\">E</mml:mi></mml:mrow><mml:mo>×</mml:mo><mml:mrow><mml:mi mathvariant=\\\"bold\\\">B</mml:mi></mml:mrow></mml:mrow></mml:math>\\n<inline-graphic xlink:href=\\\"ppcfad2c28ieqn1.gif\\\" xlink:type=\\\"simple\\\"></inline-graphic>\\n</inline-formula> flow on multiscale turbulence is studied with nonlinear gyrokinetic simulations. Simulations are based on DIII-D-like, high-confinement mode (H-mode) pedestal parameters in the regime of low ion temperature gradient drive, where there is a broad spectrum of electron temperature gradient (ETG)-driven turbulence. It is found that <inline-formula>\\n<tex-math><?CDATA ${\\\\mathbf{E} \\\\hskip -1pt \\\\times \\\\hskip -1pt \\\\mathbf{B}}$?></tex-math>\\n<mml:math overflow=\\\"scroll\\\"><mml:mrow><mml:mrow><mml:mi mathvariant=\\\"bold\\\">E</mml:mi></mml:mrow><mml:mo>×</mml:mo><mml:mrow><mml:mi mathvariant=\\\"bold\\\">B</mml:mi></mml:mrow></mml:mrow></mml:math>\\n<inline-graphic xlink:href=\\\"ppcfad2c28ieqn2.gif\\\" xlink:type=\\\"simple\\\"></inline-graphic>\\n</inline-formula> shear can have a significant effect on ETG-driven electron transport, with an unexpected transition from a turbulence stabilization regime at moderate to large shearing rates <italic toggle=\\\"yes\\\">γ</italic>\\n<sub>\\n<italic toggle=\\\"yes\\\">E</italic>\\n</sub> to a novel turbulence destabilization regime at low levels of <italic toggle=\\\"yes\\\">γ</italic>\\n<sub>\\n<italic toggle=\\\"yes\\\">E</italic>\\n</sub>. In the turbulence stabilization regime, the electron energy flux decreases monotonically with <italic toggle=\\\"yes\\\">γ</italic>\\n<sub>\\n<italic toggle=\\\"yes\\\">E</italic>\\n</sub>, even when <italic toggle=\\\"yes\\\">γ</italic>\\n<sub>\\n<italic toggle=\\\"yes\\\">E</italic>\\n</sub> is small compared to electron mode growth rates. The stabilizing effect comes dominantly from the electron, not ion, gyrokinetic equation. In the novel destabilization regime, reduction of zonal energy results from the interaction of <italic toggle=\\\"yes\\\">γ</italic>\\n<sub>\\n<italic toggle=\\\"yes\\\">E</italic>\\n</sub>-modulated nonlinear drive in the zonal ion gyrokinetic equation, increasing the electron transport over a broad range of shearing rates. Neither of these effects have been observed in previous electron-scale simulations.\",\"PeriodicalId\":20239,\"journal\":{\"name\":\"Plasma Physics and Controlled Fusion\",\"volume\":\"40 1\",\"pages\":\"\"},\"PeriodicalIF\":2.1000,\"publicationDate\":\"2024-03-07\",\"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/ad2c28\",\"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}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasma Physics and Controlled Fusion","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1088/1361-6587/ad2c28","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}
Flow-shear destabilization of multiscale electron turbulence
The impact of sheared E×B flow on multiscale turbulence is studied with nonlinear gyrokinetic simulations. Simulations are based on DIII-D-like, high-confinement mode (H-mode) pedestal parameters in the regime of low ion temperature gradient drive, where there is a broad spectrum of electron temperature gradient (ETG)-driven turbulence. It is found that E×B shear can have a significant effect on ETG-driven electron transport, with an unexpected transition from a turbulence stabilization regime at moderate to large shearing rates γE to a novel turbulence destabilization regime at low levels of γE. In the turbulence stabilization regime, the electron energy flux decreases monotonically with γE, even when γE is small compared to electron mode growth rates. The stabilizing effect comes dominantly from the electron, not ion, gyrokinetic equation. In the novel destabilization regime, reduction of zonal energy results from the interaction of γE-modulated nonlinear drive in the zonal ion gyrokinetic equation, increasing the electron transport over a broad range of shearing rates. Neither of these effects have been observed in previous electron-scale simulations.
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.