Microstructure, Renormalization, and More Eecient Vortex Methods
نویسنده
چکیده
The small-scale structure of the ow produced by vortex methods is discussed, and contrasted with the small-scale structure produced by grid methods. Particular attention is paid to the proliferation of vortex hairpins in three dimensions; its origin is analyzed, a statistical description is given, and methods for harmlessly deleting unneeded hairpins are suggested. These methods involve renormalization-group ideas and an expansion in powers of a vortex fugacity. In both theory and applications, magnet variables play a major role.
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