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Archivio digitale delle tesi discusse presso l’Università di Pisa

Tesi etd-08292023-073831


Tipo di tesi
Tesi di laurea magistrale
Autore
MANFREDINI, LORENZO
URN
etd-08292023-073831
Titolo
Centrifugal instability in a rotating plasma column
Dipartimento
FISICA
Corso di studi
FISICA
Relatori
relatore Prof. Faganello, Matteo
relatore Prof. Califano, Francesco
Parole chiave
  • centrifugal instability
  • finite Larmor radius effects
  • plasma instabilitities
  • plasma physics
Data inizio appello
13/09/2023
Consultabilità
Non consultabile
Data di rilascio
13/09/2093
Riassunto
In this thesis, we theoretically study centrifugal instability in a rotating plasma column with specific application to the Mistral experiment at PIIM lab.
The influence of ion Finite Larmor radius (FLR) effects on the instability development as well as the implications of the finite size of the device have been investigated.
The stability of the system has been studied through a linear stability analysis, considering
small parturbations to an equilibrium configuration consistent with the one observed in the Mistral experiment. The mode equation is recovered both in the MHD and two-fluid description,
incorporating in the model corrections due to FLR of ions.
The mode equation admits an analytical solution in an infinite domain. In order to
study the stability of real systems of interest, a numerical tool has been developed to solve the
mode equation in a finite-size domain.
To investigate the stability of the system, eigenvalues and eigenvectors have been obtained
numerically while varying the size of the system. The impact of the finite size of the system and
the stabilizing effect of FLR on the growth rates of the unstable modes are discussed.
An ab-initio MHD numerical code has been modified, in suitable to describe the MISTRAL device. The of the code enables the investigation of the plasma dynamics and the instability development beyond the linear description. The modifications to the code are presented in detail. The results of numerical simulations are presented and discussed.
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