Search for dissertations about: "Per Brunsell"

Showing result 1 - 5 of 9 swedish dissertations containing the words Per Brunsell.

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

   Author : Richard Fridström; Per Brunsell; Lorenzo Frassinetti; Tommaso Bolzonella; KTH; []
   Keywords : 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;

   Abstract : 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. READ MORE

4. 2. Tearing mode dynamics in the presence of resonant magnetic perturbations

   Author : Richard Fridström; Per Brunsell; Marco Cecconello; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tearing mode; plasma; fusion; reversed-field pinch; RFP; magnetic; confinement; resonant; perturbation; magnetohydrodynamics; MHD; EXTRAP T2R; Madison Symmetic Torus; Fysik; Physics;

   Abstract : Magnetically confined fusion (MCF) plasmas are typically subject to several unstable modes. The growth of one mode can limit the plasma energy confinement and might cause a termination of the plasma. Externally applied resonant magnetic perturbations (RMPs) are used to control and to mitigate some of the unstable modes. READ MORE

5. 3. Closed-loop control and identification of resistive shell magnetohydrodynamics for the reversed-field pinch

   Author : Erik Olofsson; Per Brunsell; Wolfgang Suttrop; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Plasma physics with fusion; Plasmafysik med fusion; Automatic control; Reglerteknik;

   Abstract : It is demonstrated that control software updates for the magnetic confinement fusion experiment EXTRAP T2R can enable novel studies of plasma physics. Specifically, it is shown that the boundary radial magnetic field in T2R can be maintained at finite levels by feedback. READ MORE

6. 4. Nonaxisymmetric experimental modal analysis and control of resistive wall MHD in RFPs : System identification and feedback control for the reversed-field pinch

   Author : K Erik J Olofsson; Per Brunsell; Marco Ariola; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnetic confinement fusion; Reversed-field pinch; System identification; Magnetohydrodynamics; Modal analysis; Automatic control; Resistive wall modes;

   Abstract : The reversed-field pinch (RFP) is a device for magnetic confinement of fusion plasmas. The main objective of fusion plasma research is to realise cost-effective thermonuclear fusion power plants. The RFP is highly unstable as can be explained by the theory of magnetohydrodynamics (MHD). READ MORE

7. 5. Bayesian Inference for Microwave Diagnostics at Joint European Torus

   Author : Stefan Schmuck; Per Brunsell; Thomas Jonsson; Jakob Svensson; Laurie Porte; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; ECE; Bayesian; Fourier transform; spectroscopy; joint inference; length-scale; Gaussian process; microwave diagnostic; JET; Electrical Engineering; Elektro- och systemteknik;

   Abstract : The major goal of this thesis is to perform Bayesian inference jointly for electron kinetic profiles, a toroidal magnetic field correction, diagnostic sensitivities, and wall reflection properties given noisy measurements of four microwave diagnostics at the tokamak JET. Besides the measurements, this kind of inference considers prior knowledge, like profile length-scales, to update objectively the information about the physics parameters. READ MORE