MEchanics GAthering –MEGA- Seminar: Reduced order model of drops bouncing on a vibrating surface
Event details
| Date | 28.03.2024 |
| Hour | 16:15 › 17:15 |
| Speaker | Tomas Fullana (LFMI, EPFL) |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract: Drops exhibit fascinating rebound behavior when interacting with superhydrophilic solid surfaces, such as atomically smooth mica sheets. Experimental observations show that drop bouncing occurs without the drop ever touching the solid and there is a nanometer-scale film of air that separates the liquid and solid. In the case of a vibrating stage, the drop can either remain in a 'bound' state, that will eventually lead to contact, or enter a sustained 'bouncing' state triggering harmonic oscillations. We investigate the bouncing and period-doubling thresholds up until chaos for varying peak stage accelerations and vibration numbers corresponding to the ratio between the forcing frequency and the characteristic drop oscillation frequency. We use the free software basilisk to solve the two-phase Navier-Stokes equations in an axisymmetric formulation. The numerical results demonstrate a remarkable agreement with experimental observations, facilitating a comprehensive exploration of the system's dynamics and allowing us to extend the regime diagram of previous work on a similar setup. Extracting the coefficient of restitution and the characteristic 'contact-time', we can cast a simplified nonlinear spring model that accurately predicts the drop center oscillation. Furthermore, by decomposition of the drop shape with the second spherical harmonic mode, corresponding to an ellipsoidal deformation, we can couple the drop center of mass to its deformation
Biography: Tomas obtained a PhD in mechanics in 2022 from Sorbonne Université. He is now a post-doc at EPFL at the Laboratory of Fluid Mechanics and Instabilities.
Biography: Tomas obtained a PhD in mechanics in 2022 from Sorbonne Université. He is now a post-doc at EPFL at the Laboratory of Fluid Mechanics and Instabilities.
Practical information
- General public
- Free
Organizer
- MEGA.Seminar Organizing Committee