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Localized pinning states in closed containers: Homoclinic snaking without bistability
Isabel Mercader1, Oriol Batiste, Arantxa Alonso
1Departament de Física Aplicada, Universitat Politècnica de Catalunya, 08034 Barcelona, Spain.
Summary
Binary mixtures with negative separation ratios show localized convection. Numerical studies reveal a pinning region with multiple stable states, but no bistability between conduction and container-filling states.
Area of Science:
- Fluid dynamics
- Thermodynamics
- Nonlinear phenomena
Background:
- Binary mixtures with negative separation ratios exhibit localized convection when heated from below.
- Understanding the behavior of these systems is crucial for various applications.
Purpose of the Study:
- To numerically investigate the behavior of localized convection states in binary mixtures.
- To explore the parameter space and identify stable states and transitions.
Main Methods:
- Numerical continuation was employed to trace states in a two-dimensional container.
- Experimental boundary conditions and parameter values were used.
Main Results:
- A pinning region in Rayleigh number was identified, hosting multiple stable localized convection states.
- Bistability between the conduction state and a container-filling state was absent.
Conclusions:
- The study explains the unusual absence of bistability in this system.
- The findings contribute to the understanding of pattern formation in convective systems.
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