scispace - formally typeset
Journal ArticleDOI

Can the Earth's magnetic field be simulated in the laboratory?

U Müller, +1 more
- 24 Jul 2000 - 
- Vol. 87, Iss: 9, pp 381-390
Reads0
Chats0
TLDR
The structure of the spiral flow in the liquid interior of planets is explained with the help of some model experiments in rapidly rotating spherical shells, and it is shown that spiral motion in well-conducting fluids can amplify seed magnetic fields to generate dynamo action.
Abstract
Today it is generally accepted that the Earth's magnetic field, as well as that of many other planets, is generated by buoyancy driven convection in the electrically conducting liquid cores of these rotating celestial bodies. The conversion of mechanical energy into electromagnetic energy is known as the dynamo effect. In contrast to technical dynamos, which utilize the rotational motion of a complex arrangement of wire coils and other materials of different electrical and magnetic properties, the geodynamo is based on a freely developing spiral flow in a practically homogeneous, electrically conducting liquid core domain, and is therefore termed a homogeneous dynamo. This report outlines some fundamental properties of the Earth's magnetic field. The structure of the spiral flow in the liquid interior of planets is explained with the help of some model experiments in rapidly rotating spherical shells, which were carried out by Busse and Carrigan (1974). Based on the main ideas of electromagnetism it is shown that spiral motion in well-conducting fluids, like liquid metals, can amplify seed magnetic fields to generate dynamo action. Starting from the conjectured flow structure in the Earth's interior, a conceptional and engineering design is described for a laboratory dynamo experiment. Some details of the construction of the test facility and first experimental results are presented and discussed.

read more

Citations
More filters
Journal ArticleDOI

Colloquium: Laboratory experiments on hydromagnetic dynamos

TL;DR: The first successful experiments at the sodium facilities in Riga and Karlsruhe, and on other experiments which were carried out or planned at various places in the world were reported in this paper.
Journal ArticleDOI

Magnetohydrodynamics measurements in the von Kármán sodium experiment

TL;DR: In this paper, the authors studied magnetic induction in a confined swirling flow of liquid sodium, at integral magnetic Reynolds numbers up to 50, and measured the magnetic field induced by the flow motion in the presence of a weak external field.
Journal ArticleDOI

Chemical changes induced by methyl jasmonate in oilseed rape grown in the laboratory and in the field.

TL;DR: Results suggest that spraying with MJ induces the production of secondary compounds, that is, GLS and VOCs, in Brassica plants, and MJ-treated crop plants may become less palatable to insect herbivores and more attractive to natural enemies of herbivore.
Journal ArticleDOI

On the mean-field theory of the Karlsruhe Dynamo Experiment

TL;DR: In this paper, the main predictions of mean-field dynamo theory are explained and compared with the experimental results of the dynamo experiment in the Forschungszentrum Karlsruhe.
Journal ArticleDOI

Ambivalent effects of added layers on steady kinematic dynamos in cylindrical geometry: application to the VKS experiment

TL;DR: In this article, the role of lid layers in the VKS was investigated and it was shown that lid layers can have an ambivalent effect on the efficiency of the dynamo.
References
More filters
Journal ArticleDOI

Berechnung der mittleren Lorentz-Feldstärke für ein elektrisch leitendes Medium in turbulenter, durch Coriolis-Kräfte beeinflußter Bewegung

TL;DR: In this article, the average crossproduct of velocity and magnetic field has a non-vanishing component parallel to the average magnetic field, which is the average of the products of two components of the velocity field.
Journal ArticleDOI

Experimental demonstration of a homogeneous two-scale dynamo

R. Stieglitz, +1 more
- 15 Feb 2001 - 
TL;DR: In this paper, it has been shown theoretically that homogeneous kinematic dynamo action is possible for many unconfined and confined velocity fields, but a rigorous experimental validation is still lacking.
Journal ArticleDOI

Dynamo Action of Fluid Motions with Two-Dimensional Periodicity

TL;DR: In this article, the authors considered the special case of spatially periodic motions with three components functions of the two Cartesian coordinates y and z only, and showed that the two-dimensional spatially-periodic motion u = (cos y, cos z, sin z and sin y) is a first-order dynamo, at least for almost all resistivities.
Journal ArticleDOI

A Model of the Geodynamo

TL;DR: In this paper, the problem of the generation of the geomagnetic field by convection in the Earth's core is considered and the complete hydromagnetic problem including the Lorentz force is solved in the case of a cylindrical configuration.
Related Papers (5)
Trending Questions (1)
Is it possible to artificially replicate the Earth's magnetic field?

Yes, it is possible to replicate the Earth's magnetic field in a laboratory using a dynamo experiment.