A Ritz variational principle for local collisionless gyrokinetic instabilities

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Stephens, C. D., Li, P. -Y.
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912214254878720
author Stephens, C. D.
Li, P. -Y.
author_facet Stephens, C. D.
Li, P. -Y.
contents Turbulence driven by gyrokinetic instabilities is largely responsible for transport in magnetic fusion devices. To estimate this turbulent transport, integrated modeling codes often use mixing length estimates in conjunction with reduced models of the linearized gyrokinetic equation. One common method of formulating and solving the linearized gyrokinetic eigenvalue problem equation uses a Ritz variational principle, particularly in the local collisionless limit. However, the variational principle as typically stated in the literature is mathematically incorrect. In this work, we derive a mathematically correct form of the variational principle that applies to local linear collisionless gyrokinetics in general geometry with electromagnetic effects. We also explicitly derive a weak form of the gyrokinetic field equations suitable for numerical applications.
format Preprint
id arxiv_https___arxiv_org_abs_2501_00698
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Ritz variational principle for local collisionless gyrokinetic instabilities
Stephens, C. D.
Li, P. -Y.
Plasma Physics
Turbulence driven by gyrokinetic instabilities is largely responsible for transport in magnetic fusion devices. To estimate this turbulent transport, integrated modeling codes often use mixing length estimates in conjunction with reduced models of the linearized gyrokinetic equation. One common method of formulating and solving the linearized gyrokinetic eigenvalue problem equation uses a Ritz variational principle, particularly in the local collisionless limit. However, the variational principle as typically stated in the literature is mathematically incorrect. In this work, we derive a mathematically correct form of the variational principle that applies to local linear collisionless gyrokinetics in general geometry with electromagnetic effects. We also explicitly derive a weak form of the gyrokinetic field equations suitable for numerical applications.
title A Ritz variational principle for local collisionless gyrokinetic instabilities
topic Plasma Physics
url https://arxiv.org/abs/2501.00698