Convection in Rotating Spherical Fluid Shells
نویسنده
چکیده
Convection driven by thermal buoyancy in rotating spherical bodies of fluid has long been recognized as a fundamental process in the understanding of the properties of planets and stars. Since these objects are rotating in general and since their evolution is associated with the transport of heat from their interiors convection influenced by the Coriolis force does indeed play a dominant role in the dynamics of their fluid parts. In the case of the Earth it is the generation of the geomagnetic field by motions in the molten outer iron core which has stimulated much interest in the subject of convection in rotating spheres. But the zones and belts seen on Jupiter are a just as interesting phenomenon driven by convection in the deep atmosphere of the planet. Similarly, the differential rotation of the sun and its magnetic cycle are intimately connected with the solar convection zone encompassing the outer 29 percent of the Sun in terms of its radial extent. Theoretical studies of convection in rotating fluid spheres started about 50 years ago. The attention was restricted to the linear problem of the onset of convection and for simplicity axisymmetric motions were assumed. An account of these early efforts can be found in Chandrasekhar’s famous treatise (1961) and in the papers by Bisshopp and Niiler (1965) and by Roberts
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