Biot-Savart helicity versus physical helicity: A topological description of ideal flows
نویسندگان
چکیده
منابع مشابه
The topological properties of magnetic helicity
The relation of magnetic helicity to the topological structure of field lines is discussed. If space is divided into a collection of flux tubes, magnetic helicity arises from internal structure within a flux tube, such as twist and kinking, and external relations between flux tubes, i.e. linking and knotting. The concepts of twist number and writhing number are introduced from the mathematical-...
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We present a version of a dynamical spectral model for large eddy simulation based on the eddy damped quasinormal Markovian approximation [S. A. Orszag, in, edited by R. Balian, Proceedings of Les Houches Summer School, 1973 (Gordon and Breach, New York, 1977), p. 237; J. P. Chollet and M. Lesievr, J. Atmos. Sci. 38, 2747 (1981)]. Three distinct modifications are implemented and tested. On the ...
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Any divergenceless vector field defined in a 3-dimensional manifold defines an integral quantity called the helicity that measures the way in which any pair of integral lines curl to one another. In the case of Classical Electrodynamics in vacuum, the natural helicity invariant, called the electromagnetic helicity, has an important particle meaning: the difference between the numbers of rightan...
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ژورنال
عنوان ژورنال: Journal of Mathematical Physics
سال: 2014
ISSN: 0022-2488,1089-7658
DOI: 10.1063/1.4889935