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Updated: Jul 8, 2025
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Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing
Published on: February 13, 2018
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Fast-slow wave transitions induced by a random mean flow.
S Boury1, O Bühler1, J Shatah1
1Courant Institute of Mathematical Sciences, New York University, New York, New York 10012, USA.
Physical Review. E
|December 20, 2023
Summary
Dispersive waves in random flows can shift from fast to slow, changing their behavior. This transition depends on wave properties and flow dynamics, especially for unsteady flows.
Area of Science:
- Fluid dynamics
- Atmosphere-ocean systems
- Wave propagation
Background:
- Recent asymptotic results in atmosphere-ocean fluid dynamics.
- Understanding wave behavior in complex flows is crucial.
Purpose of the Study:
- Investigate conditions for group velocity changes in dispersive waves.
- Analyze fast-slow wave transitions due to Doppler shifting and refraction.
Main Methods:
- Idealized numerical and theoretical study.
- Analysis of two-dimensional dispersive waves in random mean flows.
Main Results:
- Identified conditions on dispersion relation and mean flow amplitude for fast-slow transitions.
- Determined a finite amplitude threshold for steady mean flows.
- Showed that unsteady flows can drive transitions regardless of amplitude.
Conclusions:
- Fast-slow wave transitions are possible and depend on flow characteristics.
- Unsteady flows significantly impact wave behavior and long-term fate.
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