@article{FayzrakhmanovaStraube2009, author = {Fayzrakhmanova, Irina S. and Straube, Arthur V.}, title = {Stick-slip dynamics of an oscillated sessile drop}, issn = {1070-6631}, doi = {10.1063/1.3174446}, year = {2009}, abstract = {We consider theoretically the dynamics of an oscillated sessile drop of incompressible liquid and focus on the contact line hysteresis. We address the situation of the small-amplitude and high-frequency oscillations imposed normally to the substrate surface. We deal with the drop whose equilibrium surface is hemispherical and the equilibrium contact angle equals pi/2. We apply the dynamic boundary condition that involves an ambiguous dependence of the contact angle on the contact line velocity: The contact line starts to slide only when the deviation of the contact angle exceeds a certain critical value. As a result, the stick-slip dynamics can be observed. The frequency response of surface oscillations on the substrate and at the pole of the drop are analyzed. It is shown that novel features such as the emergence of antiresonant frequency bands and nontrivial competition of different resonances are caused by contact line hysteresis.}, language = {en} } @article{FayzrakhmanovaStraubeShklyaev2011, author = {Fayzrakhmanova, Irina S. and Straube, Arthur V. and Shklyaev, Sergey}, title = {Bubble dynamics atop an oscillating substrate: Interplay of compressibility and contact angle hysteresis}, series = {Physics of fluids}, volume = {23}, journal = {Physics of fluids}, number = {10}, publisher = {American Institute of Physics}, address = {Melville}, issn = {1070-6631}, doi = {10.1063/1.3650280}, pages = {6}, year = {2011}, abstract = {We consider a sessile hemispherical bubble sitting on the transversally oscillating bottom of a deep liquid layer and focus on the interplay of the compressibility of the bubble and the contact angle hysteresis. In the presence of contact angle hysteresis, the compressible bubble exhibits two kinds of terminal oscillations: either with the stick-slip motion of the contact line or with the completely immobile contact line. For the stick-slip oscillations, we detect a double resonance, when the external frequency is close to eigenfrequencies of both the breathing mode and shape oscillations. For the regimes evolving to terminal oscillations with the fixed contact line, we find an unusual transient resembling modulated oscillations.}, language = {en} }