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Three-dimensional localized coherent structures of surface turbulence: Model validation with experiments and further
E A Demekhin1, E N Kalaidin, S Kalliadasis
1Southern Research Center of Russian Academy of Sciences, Kuban State University, Stavropolskaya Street 149, Krasnodar 350040, Russia.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
This study experimentally validates the Kapitsa-Shkadov model for surface turbulence in thin liquid films. Results confirm the model
Area of Science:
- Fluid Dynamics
- Nonlinear Dynamics
- Surface Phenomena
Background:
- Surface turbulence in thin liquid films is a complex phenomenon.
- The Kapitsa-Shkadov model offers a theoretical framework for understanding this turbulence.
- Previous theoretical studies by Demekhin have explored this model.
Purpose of the Study:
- To experimentally validate the Kapitsa-Shkadov model for thin liquid film flow.
- To assess the model's predictions for three-dimensional nonlinear localized coherent structures.
- To investigate instabilities and transitions leading to these coherent structures.
Main Methods:
- Experimental validation of the Kapitsa-Shkadov model.
- Devising simple experiments to study instabilities and transitions.
- Performing time-dependent computations for structure formation and interaction.
Main Results:
- Experimental results show good agreement with the Kapitsa-Shkadov model's predictions.
- Surface turbulence in water films occurs around an inlet Reynolds number of 40 at 15°C.
- Computations demonstrated the formation and interaction of coherent structures.
Conclusions:
- The Kapitsa-Shkadov model is experimentally validated for surface turbulence.
- The model accurately predicts nonlinear localized coherent structures.
- Experimental and computational findings support the theoretical framework.
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