Sökning: "toroidal instabilities"

Visar resultat 21 - 24 av 24 avhandlingar innehållade orden toroidal instabilities.

1. 21. Computational Studies of Magnetohydrodynamic Stability for Reversed-Field Pinches and Tokamaks

   Författare :Donghui Liu; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : This work describes the ideal & resistive Magnetohydrodynamic (MHD) stability properties of Tokamak and Reversed-Field Pinch (RFP) plasmas. The first four papers are concerned with the cylindrical approximation of RFPs and tokamaks whereas the final two papers deal with a fully toroidal description. LÄS MER

3. 22. Resistive Wall Mode Stability and Control in the Reversed Field Pinch

   Författare :Dmitriy Yadikin; Per Brunsell; Mikhail Gryaznevich; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Resistive wall modes; RWM; active control; feedback; MHD modes; Reversed-Field pinch; RFP; intelligent shell; mode control; Electrophysics; Elektrofysik;

   Sammanfattning : Control of MHD instabilities using a conducting wall together with external magnetic fields is an important route to improved performance and reliability in fusion devices. Active control of MHD modes is of interest for both the Advanced Tokamak and the Reversed Field Pinch (RFP) configurations. LÄS MER

4. 23. Coupling and Absorption of Lower Hybrid Waves in Current Profile Control Experiments in the JET Tokamak

   Författare :Annika Ekedahl; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Current drive with radio frequency waves in the lower hybrid frequency range is an important method of current profile control via non-inductive current drive in tokamaks. This thesis is concerned with profile control experiments, carried out with the lower hybrid current drive system in the Joint European Torus (JET) tokamak, with the aim to explore scenarios for operation in high confinement regimes with peaked pressure profiles. LÄS MER

5. 24. Resonant magnetic perturbation effect on the tearing mode dynamics : Novel measurements and modeling of magnetic fluctuation induced momentum transport in the reversed-field pinch

   Författare :Richard Fridström; Per Brunsell; Lorenzo Frassinetti; Tommaso Bolzonella; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; RFP; reversed-field pinch; tokamak; tearing mode; RMP; fusion; plasma; resonant magnetic perturbation; stochastic; magnetic; field; viscosity; mode; locking; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : The tearing mode (TM) is a resistive instability that can arise in magnetically confined plasmas. The TM can be driven unstable by the gradient of the plasma current. When the mode grows it destroys the magnetic field symmetry and reconnects the magnetic field in the form of a so-called magnetic island. LÄS MER