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Register a new userFinite-time localized singularities as a mechanism for turbulent dissipation
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Added by
Christophe Josserand
Publication date
2019
fields
Physics
and research's language is
English
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We provide a scenario for a singularity-mediated turbulence based on the self-focusing non-linear Schrodinger equation, for which sufficiently smooth initial states leads to blow-up in finite time. Here, by adding dissipation, these singularities are regularized, and the inclusion of an external forcing results in a chaotic fluctuating state. The strong events appear randomly in space and time, making the dissipation rate highly fluctuating. The model shows that: i) dissipation takes place near the singularities only, ii) such intense events are random in space and time, iii) the mean dissipation rate is almost constant as the viscosity varies, and iv) the observation of an Obukhov-Kolmogorov spectrum with a power law dependence together with an intermittent behavior using structure functions correlations, in close correspondence with fluid turbulence.
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