The Influence of a Heterogeneous Surface on the Free Volume Oscillations of an Oblate Gas Bubble

Abstract

Abstract The natural oscillations of a cylindrical gas bubble surrounded by an incompressible fluid with free interface are considered. The bubble has an equilibrium cylindrical shape and is bounded axially by two parallel solid surfaces. Dynamics of contact lines is taken into account by an effective boundary condition: velocity of the contact line is assumed to be proportional to contact angle deviation from the equilibrium value. The equilibrium contact angle is right. Different Hocking parameters determine individual damping rates, but dissipation in the integral system is determined by their total contribution. The frequency of the volume (breathing) harmonic of free oscillations can vanish in a certain interval of the values of the Hocking parameter for homogeneous plate surface. However, Surface inhomogeneity destroys this monotonic damping effect.