Dynamic instabilities at interfaces: from contact lines to fracture mechanics
Event details
| Date | 03.02.2016 |
| Hour | 14:00 › 15:00 |
| Speaker |
Dr. John Kolinski, Hebrew University of Jerusalem, Israel Bio : John Kolinski studied Applied Mathematics (Sc.M. 2010) and Applied Physics (Ph.D. 2014) at Harvard University, completing a PhD under the supervision of L. Mahadevan and Shmuel Rubinstein on the role of air in droplet impact. John is presently a Fulbright post-doctoral fellow with Eran Sharon and Jay Fineberg at the Hebrew University of Jerusalem, where his research is focused on interfacial instabilities in soft matter. |
| Location | |
| Category | Conferences - Seminars |
Abstract :
The mechanics of fluids and solids at a material interface are often dynamic, and prone to developing instabilities. Here, we experimentally study two different forms of interfacial instability: dynamic wetting beneath an impacting drop, and the propagation of a crack through a solid material. While both of these cases permeate our existence, they remain poorly understood due to the complexity of dynamics at the interface. As an impacting a drop nears the surface, the air fails to drain and is instead compressed. We directly measure the liquid-air interface on the nanometer-scale, and show how the air mediates the growth of liquid-solid contact, leading to an unexpected contact line velocity. Separately, we investigate how material inhomogeneity can alter the dynamic fracture of brittle materials. We controllably modify the constituents of our material sample, load it in tension, and image it after a crack initiates. We will show that the material’s inhomogeneity can destabilize the crack front during dynamic fracture, diverting it from the plane of propagation.
The mechanics of fluids and solids at a material interface are often dynamic, and prone to developing instabilities. Here, we experimentally study two different forms of interfacial instability: dynamic wetting beneath an impacting drop, and the propagation of a crack through a solid material. While both of these cases permeate our existence, they remain poorly understood due to the complexity of dynamics at the interface. As an impacting a drop nears the surface, the air fails to drain and is instead compressed. We directly measure the liquid-air interface on the nanometer-scale, and show how the air mediates the growth of liquid-solid contact, leading to an unexpected contact line velocity. Separately, we investigate how material inhomogeneity can alter the dynamic fracture of brittle materials. We controllably modify the constituents of our material sample, load it in tension, and image it after a crack initiates. We will show that the material’s inhomogeneity can destabilize the crack front during dynamic fracture, diverting it from the plane of propagation.
Practical information
- Expert
- Free
- This event is internal
Organizer
- IGM
Contact
- Géraldine Palaj