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Updated: Jul 13, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Clustering of matter in waves and currents
Marija Vucelja1, Gregory Falkovich, Itzhak Fouxon
1Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Summary
The entropy production rate, a measure of density fluctuations, is typically zero in random wave flows. However, waves and currents together realistically create ocean pollutant patchiness.
Area of Science:
- Fluid dynamics
- Oceanography
- Statistical physics
Background:
- Small-scale density inhomogeneities, or entropy production rate, are crucial in understanding fluid dynamics.
- The sum of Lyapunov exponents quantifies this rate in random flows.
Purpose of the Study:
- To derive analytic formulas for the entropy production rate in different flow conditions.
- To investigate the role of waves and currents in creating oceanic patchiness.
Main Methods:
- Derivation of analytic formulas for the entropy production rate.
- Analysis of flows involving weakly interacting waves and combined waves and currents.
- Estimation of the rate and fractal dimension of density distribution.
Main Results:
- The entropy production rate is zero up to the fourth order in wave amplitude for weakly interacting waves.
- A non-zero rate is found in flows combining waves and currents.
- Interplay of waves and currents realistically models pollutant patchiness.
Conclusions:
- Weakly interacting waves do not significantly contribute to density inhomogeneities at lower orders.
- The interaction between waves and currents is a key mechanism for generating patchiness in pollutant distribution.
- This mechanism is relevant for understanding ocean surface dynamics.
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