ISSN:0863-1042    

DOI:10.1002/ctpp.2150320302

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractThe diffusion and the exponential divergence of neighbouring trajectories which characterize the stochastic magnetic field are reviewed. The effect of these properties on heat and current transport leads to an increase of the radial heat diffusivity and a reduction of the toroidal electric conductivity. The finite connection length to the wall in the perturbed layer determines the regular heat and particle deposition pattern.

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320303

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320304

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320305

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractDevelopment of Divertor Concept for Optimized Stellarators. 1. Stellarator optimization. 2. Configurational aspects. 3. Field line tracing for investigation of diversion properties. 4. Simplified SOL models: one‐dimensional estimates and Monte Carlo simulations. 5. Divertor troughs. 6. Discussion and outloo

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320306

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractInvestigations of various vacuum magnetic fields of Helias configurations allowed a divertor concept to be developed. Here, the structure of the magnetic field lines between the plasma surface, i.e. the last closed magnetic surface, and the plasma facing surfaces of the helical troughs is investigated. Magnetic field lines, starting at the helical troughs, are traced until they end at the troughs. The resulting mapping is studied in detail.

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320307

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractThe scrape off layer (SOL) of a confined plasma (Fig. 1a) is in many respects in a state far from, thermodynamic equilibrium:The energy diffusing outward from the plasma core across the separatrix is condensed in the thin SOL to a strong energy flux along the magnetic field.The recycling of cold neutrals from the limiter or divertor target gives rise to a strong temperature gradient from the hot midplane region to the relatively cold recycling zone.For long mean free path length in the plasma relative to the extension of the recycling zone the thermalization in the recycling zone may be incomplete.The potential gradient length in the sheath in front of the target is small as compared to the mean free path length; the velocity distributions of ions and electrons as determined by the electric field are far from being Maxwellians there.Thus the follwing topics will be discussed in this paper:Parallel transport (electron heat flow, ion viscosity)RecyclingSheath structure (grazing incidence of magnetic field, secondary electrons).Boundary conditions for fluid modelsNumerical illustrations for these kinetic effects are given from a 1d particle‐in‐cell code including Coulomb collisions [1].Not treated are kinetic effects connected with instabilities, perpendicular transport, neutrals and impurit

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320308

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320309

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320310

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractAn electrostatic sheath formation on carbon and molybdenum target plates for plasmas with electrons of two different temperatures is analyzed by a simple formulation including the effect of secondary electron emission from the target plate. A modified Bohm criterion is given in terms of effective electron temperature which defines the ion sound velocity in two component plasmas. Hot electrons and the associated secondary electrons greatly modify the charge balance in the sheath. They change the sheath voltage and consequently the heat transmission characteristics. A critical amount of hot electrons for sharp increase in the sheath voltage is given by a simple formula.

ISSN:0863-1042    

DOI:10.1002/ctpp.2150320311

出版商:WILEY‐VCH Verlag    

年代:1992

数据来源: WILEY