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Updated: Jul 4, 2026
07:28
Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
Solitary Marangoni-driven convective structures in bistable chemical systems
1Nonlinear Physical Chemistry Unit and Center for Nonlinear Phenomena and Complex Systems, Université Libre de Bruxelles (ULB), CP 231, 1050 Brussels, Belgium. lrongy@ulb.ac.be
Summary
Marangoni flows alter bistable chemical fronts, changing their speed and stability. These convective flows can even reverse the front
Area of Science:
- Physical Chemistry
- Fluid Dynamics
- Chemical Kinetics
Background:
- Bistable chemical fronts exhibit complex dynamics influenced by various factors.
- Marangoni-driven convection arises from surface tension gradients and can deform interfaces.
Purpose of the Study:
- Investigate the nonlinear dynamics of bistable chemical fronts under Marangoni flow.
- Analyze how surface-active species and bistable kinetics interact with convection.
Main Methods:
- Simulations of two-dimensional Navier-Stokes equations.
- Coupling fluid dynamics with a reaction-diffusion-convection equation.
- Parametric study varying Marangoni number (M) and kinetic parameter (d).
Main Results:
- Marangoni flows significantly alter front shape and propagation speed.
- Convection can change the relative stability of steady states.
- Direction of front propagation can be reversed compared to pure reaction-diffusion systems.
Conclusions:
- Marangoni convection introduces significant nonlinear effects on bistable chemical fronts.
- The interplay between flow and kinetics dictates front dynamics and stability.
- System behavior is tunable via Marangoni number and kinetic parameters.
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