摘要:

A general method is developed for calculating the width, due to magnetic perturbations, of the scrape‐off layer of a tokamak with a divertor. The method, which assumes the plasma particles are tied to the field lines, should provide a good estimate provided the predicted width is large compared to that given by particle diffusion or finite particle drift orbit effects. The general theory is applied to a simple analytic model of a divertor to indicate the expected magnitude of the scrape‐off layer thickness.

ISSN:0031-9171    

DOI:10.1063/1.862277

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Whistler waves launched from an antenna damp away for small incident power. With increasing power, undamped nondiverging waves (the ducted waves) are observed, together with a field‐aligned density trough and electron heating. However, the density trough is found not only in the wave propagation regime (&ohgr;/&ohgr;c<1), but also in the wave evanescence regime (&ohgr;/&ohgr;c≳1). This implies that the density depression is mainly created by the effect of the antenna near‐zone field rather than by the wave radiation pressure. The intense localized field near the antenna gives rise to electron heating which leads to the density trough. The ducting of antenna‐launched whistler waves has been explained as a filamentation instability in terms of nonlinear wave‐plasma interactions.

ISSN:0031-9171    

DOI:10.1063/1.862278

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A Galerkin–Ritz procedure for any arbitrary system of field equations is shown to follow generically from ’’two‐functional’’ variational conditions. The initial‐value problem for boundary‐free incompressible Navier–Stokes flow is solved analytically in the two‐parameter‐function approximation.

ISSN:0031-9171    

DOI:10.1063/1.862256

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A highly viscous fluid separates a smooth plate moving in its own plane and a wavy plate. Due to the wavy striations, the mean flow is decreased and the mean drag is increased. The waviness makes the fluid appear to be anisotropic.

ISSN:0031-9171    

DOI:10.1063/1.862279

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The onset of natural convection in a cylinder of water‐saturated porous media is considered. The dependence of the critical Rayleigh number and the preferred convective motion on both the aspect ratio of the cylinder and the temperature difference is established.

ISSN:0031-9171    

DOI:10.1063/1.862280

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A numerical solution of the Benjamin–Ono equation for internal waves shows soliton behavior. Two and three Lorentzian solitons pass through one another unscathed. An initial Lorentzian with larger than soliton amplitude decays into solitons, with velocities predicted by the five conservation laws.

ISSN:0031-9171    

DOI:10.1063/1.862281

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The spectrum of axisymmetric torsional Alfve´n waves propagating in a cylindrical, nonuniform, resistive plasma waveguide has been analyzed by a method of singular perturbations. It is indicated why some experiments show a continuous spectrum and others a discrete spectrum.

ISSN:0031-9171    

DOI:10.1063/1.862282

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The saturation level of drift waves in a multispecies plasma is estimated. The convection rate of each species across the plasma is calculated.

ISSN:0031-9171    

DOI:10.1063/1.862283

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The spatial extent of magnetic field sources in laser‐irradiated targets can be small enough for the well‐known nonlocal nature of plasma conductivity to strongly affect magnetic field diffusion and saturation.

ISSN:0031-9171    

DOI:10.1063/1.862284

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

It is shown that recently published observations of angle‐ and polarization‐dependent absorption of intense laser light are consistent with computer simulations of resonance absorption in a steepened plasma profile, with the additional assumption of a modestly rippled critical surface.

ISSN:0031-9171    

DOI:10.1063/1.862254

出版商:AIP    

年代:1978

数据来源: AIP