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Field experiment in sils maria switzerland 2004 re

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Unformatted text preview: iment mentioned in previous lectures, see figure in the next slide). This corresponds to scales more than three times smaller than η. Field experiment in Sils Maria, Switzerland, 2004 Reλ= 7⋅103 Thus, because it is not possible to separate eddies Thus, into clearly defined classes according to the source of their energy (decompositions?); and as there is no object, (decompositions?); for present purposes, in making a distinction based on size between cumulus eddies and eddies a few metres in diameter (since both are small compared with our coordinate chequer), therefore a single coefficient is used to represent the effect produced by eddies of all sizes and descriptions. (eddy viscosity). (eddy RICHARDSON 1922.. Decompositions, locality, in general, and of Decompositions, cascade, energy (or whatever) flux, in particular. Any decomposition results in a nontrivial bidirectional relation between small and the large scales (whatever this means) which is non-local (functional) both in space and time (i.e. history-dependent). Hence there is little chance that this dependence can be local (in several meanings) as is insisted for quite a period of time. Today – also in view of accumulating evidence - its is becoming clear that locality is at best an extremely crude approximation which in many cases is good for empirical purposes, but not as a basis for studying the physics of turbulence. All the attempts to find a ‘good' decomposition are related to what Betchov called the ‘dream of linearized physicists', i.e. a superposition of some, desirably simple elements. The dream is, of course, to find sets consisting of small number of weakly interacting elements/objects adequately representing the turbulent field. The dream is, of course, to find sets consisting of small number of weakly interacting elements/objects adequately representing the turbulent field. Those known so far are interacting strongly and mostly nonlocally*. This is a reflection of one of the central difficulties in 'solving the turbulence problem' as a whole, in general, and the ‘closure problem' such as LES...
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