Sökning: "quasilinear diffusion"
Visar resultat 1 - 5 av 7 avhandlingar innehållade orden quasilinear diffusion.
Sammanfattning : In this work we address the closure issue in kinetic and fluid descriptions of turbulent plasmas. In fluid description contribution has been made to the nonlinear closure by Mattor and Parker [Phys. Rev. Lett. LÄS MER
Sammanfattning : One of the main challenges for the realization of a working fusion power plant is an increased detailed understanding of kinetic phenomena in toroidal plasmas. The tokamak is a toroidal, magnetically confined plasma device and is currently the main line towards a power plant. LÄS MER
Sammanfattning : In optics an important nonlinear effect is manifested by the fact that the refractive index, in addition to its frequency dependence, also depends on the intensity of the light. Nonlinear effects are present within a wide range of optical applications e.g. the fast growing fields of fiber-optic communication and all-optical signal processing. LÄS MER
Sammanfattning : Experiments for the development of fusion power that are based on magnetic confinement deal with plasmas that inevitably contain energetic (non-thermal) particles. These particles come e.g. from fusion reactions or from external heating of the plasma. LÄS MER
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