| Wed February 3rd 2016 16:00 – 16:30 HR Z203 | Seminar | Solid wetting ridge rotation determines liquid contact angle Mathijs van Gorcum |
Details:The dynamics of wetting on soft surfaces is dominated by the solid properties for a large velocity range. The balance of capillary and elastic forces creates a strong deformation of the soft solid into a sharp ridge shape. It has been theorized that the dynamic contact angle is determined by a rotation of the shape of the ridge. Here we show that there is a direct relation between the microscopic ridge shape rotation and the macroscopic contact angle. Direct visualization of the wetting ridge reveals that the relation of the wetting ridge rotation as a function of contact line speed corresponds one to one with the macroscopic contact angle difference. The depinning from the wetting ridge and formation of a new ridge, resulting in a stick-slip-like motion, is also studied by observing the ridge dynamics. | ||
