Sökning: "quasilinear diffusion"

Visar resultat 6 - 8 av 8 avhandlingar innehållade orden quasilinear diffusion.

  1. 6. Ion cyclotron resonance heating and current drive in tokamaks

    Författare :Johan Carlsson; KTH; []
    Nyckelord :;

    Sammanfattning : In this thesis numerical studies, performed with theMonte-Carlo code FIDO of the evolution of the resonant-iondistribution function in the presence of ion cyclotronresonance heating (ICRH) in toroidal geometry are presented. Inparticular it is pointed out how the absorption of toroidalmomentum from a wave field with finite parallel wave numberscauses spatial drift and diffusion, which together with thefinite orbit widths of the tail ions is shown to have a largeeffect on the temperature profile of the resonant ion speciesand also to cause losses of high-energy ions to the wall. LÄS MER

  3. 7. Conservation Laws, Numerical Schemes and Control Strategies for Sedimentation and Wastewater Treatment

    Författare :Sebastian Farås; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conservation law; Temple class system; numerical scheme; continuous sedimentation;

    Sammanfattning : A consistent theme throughout this thesis is quasilinear partial differential equations (PDEs) appearing in one-dimensional models of sedimentation for solid-liquid separation of suspensions. We mainly focus on continuous sedimentation in so-called clarifier-thickeners (CTs), which are found in mineral processing and wastewater treatment. LÄS MER

  4. 8. Dynamics of Fast Ions in Tokamaks

    Författare :Per Helander; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Fast ions play a prominent role in the heating of tokamak plasmas by, e.g., neutral- beam injection, ion-cyclotron-resonance heating, and alpha-particle heating. In this thesis, a number of physical and mathematical problems concerning the dynamics of fast ions in tokamaks are addressed. LÄS MER