摘要:

This paper treats the dynamical conditions that obtain when long straight parallel twisted flux tubes in a highly conducting fluid are packed together in a broad array. It is shown that there is generally no hydrostatic equilibrium. In place of equilibrium there is a dynamical nonequilibrium, leading to neutral point reconnection and progressive coalescence of neighboring tubes (with the same sense of twisting), forming tubes of larger diameter and reduced twist. The magnetic energy in the twisting of each tube declines toward zero, dissipated into small-scale motions of the fluid and thence into heat.

ISSN:0309-1929    

DOI:10.1080/03091928208209027

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The full Boussinesq equations for hydromagnetic convection are derived and shown to include the effects of magnetic buoyancy. Instabilities caused by magnetic buoyancy are analyzed and their roles in double convection are brought out.

ISSN:0309-1929    

DOI:10.1080/03091928208209028

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The weak-field Benard-type dynamo treated by Soward is considered here at higher levels of the induced magnetic field. Two sources of instability are found to occur in the intermediate field regimeM ∼ T1/12, whereMandTare the Hartmann and Taylor numbers. On the time scale of magnetic diffusion, solutions may blow up in finite time owing to destabilization of the convection by the magnetic field. On a faster time scale a dynamic instability related to MAC-wave instability can also occur. It is therefore concluded that the asymptotic structure of this dynamo is unstable to virtual increases in the magnetic field energy.

ISSN:0309-1929    

DOI:10.1080/03091928208209029

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Perturbation theory methods are developed for the kinematic geodynamo equations. The vector Green's function is constructed for the unperturbed equation, which includes the axisymmetric differential rotation. While investigating the perturbation series, we consider a special case in which the decay rates of the axisymmetric toroidal and poloidal dipoles are degenerate. For a number of models within the framework of the theory developed, estimates are given for generation conditions and for observed characteristics of the geomagnetic field.

ISSN:0309-1929    

DOI:10.1080/03091928208209030

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Stability analysis is formulated for a two-layer fluid model in which the upper and lower layers are convectively stable and unstable, respectively. With discontinuities in viscosity and conductivity at the interface, the exchange of stability does not generally hold and overstability is possible. A detailed analytical treatment is presented for the case of small viscosity and conductivity in which viscous and conducting boundary layers are formed at the interface.

ISSN:0309-1929    

DOI:10.1080/03091928208209031

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

By E. R. Lapwood and T. Usami, Cambridge University Press, 1981. xii + 243 pp. $25 (ISBN 0 521 23563 7).

ISSN:0309-1929    

DOI:10.1080/03091928208209032

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

By John W. Elder. Academic Press, 1981. 508 pp. ($20.60) (ISBN 0 12 236450.3).

ISSN:0309-1929    

DOI:10.1080/03091928208209033

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

By John Verhoogen. National Academy Press, 1980. 139 pp. ($9.00) (ISBN 0 309 03076 5) 1980.

ISSN:0309-1929    

DOI:10.1080/03091928208209034

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Edited by L. Bengtsson, M. Ghil and E. Kallen. Springer-Verlag, New York, USA, 1981. 1–330 pp. ($18) (ISBN 0 387 906320).

ISSN:0309-1929    

DOI:10.1080/03091928208209035

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Edited by D. J. Southwood. Center for Academic Publications, Japan/Tokyo and D. Reidel Publishing Company, Dordrecht, Boston and London, 1981. vii + 145 pp. (Dfl. 60, US $29.50) (ISBN 90 277 1232 8)

ISSN:0309-1929    

DOI:10.1080/03091928208209036

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor