Sökning: "drift waves"

Visar resultat 16 - 20 av 37 avhandlingar innehållade orden drift waves.

  1. 16. Space Plasma Dynamics : Instabilities, Coherent Vortices and Covariant Parametrization

    Författare :David Sundkvist; Jan-Erik Wahlund; Andris Vaivads; Stuart Bale; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; space physics; plasma; instabilities; turbulence; coherent structures; vortex; self-organization; magnetosphere; waves; electromagnetism; covariant; space instrumentation; Rymd- och plasmafysik; Space physics; Rymdfysik;

    Sammanfattning : The magnetospheric cusps are two funnel-like regions of Earth's magnetosphere where solar wind plasma can have direct access to the ionosphere. The cusps are very dynamic regions where wave-particle interactions continuously take place and redistribute energy among different particle populations. LÄS MER

  3. 17. Microinstabilities in Advanced Tokamak and Stellarator Geometries

    Författare :Ansar Mahmood; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tokamaks; microinstabilities; fusion plasmas; ITG; drift waves; stellarators;

    Sammanfattning : The anomalous particle and heat transport observed in magnetically confined plasmas is generally attributed to plasma turbulence driven by short-scale instabilities, called microinstabilities. Understanding the stability limits of microinstabilities and their dependency on the equilibrium configuration is of paramount importance in the effort to predict the performance of future fusion devices such as the International Thermonuclear Experimental Reactor (ITER). LÄS MER

  4. 18. Transport Barriers in Plasmas and Fluids

    Författare :Robert Moestam; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DNS; transport barriers; Zonal flows; L-H mode transition; turbulence simulations; drift waves; flux tube simulations; nonlinear instabilities; linear instabilities;

    Sammanfattning : In the present work different mechanisms for generation and suppression of turbulence are studied. The suppression of nonlinearly generated turbulence stabilized by temperature boundary conditions as well as turbulence generated by linear instabilities and suppressed by nonlinearly generated secondary flows are treated. LÄS MER

  5. 19. Fast ions and turbulent particle transport in tokamaks

    Författare :Frida Eriksson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NBI; numerical modelling; turbulence; drift waves; bump-on-tail; density peaking; Fusion plasma physics; wave-particle interaction;

    Sammanfattning : The presence of highly energetic (fast) ions, be it fusion born alpha particles or ions accelerated by auxiliary heating schemes, can affect the heating and transport of all particles in the plasma through two main mechanisms. First, fast ions may excite fast ion driven instabilities. LÄS MER

  7. 20. Transport barriers in plasmas and fluids

    Författare :Robert Moestam; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; drift waves; transport barriers; vortex equation; linear instabilities;

    Sammanfattning : .... LÄS MER