HYDRODYNAMIC STABILITY OF A WATER VAPOR NANOBUBBLE IN WATER UNDER NORMAL CONDITIONS

The hydrodynamic stability of a water vapor nanobubble in water under normal conditions is investigated. The hydrodynamic equation describing the motion of the bubble boundary taking into account the bubble charge and the dependence of the surface tension coefficient on the radius, as well as the heat balance equation of the nanobubble are used for the study. Taking into account the nanobubble charge leads to a competition between capillary and electrostatic forces, which affects the hydrodynamic stability of the nanobubble. The main equations are written down, and an analysis of the stability of small disturbances is carried out. The characteristic equation is obtained and the stability conditions of the nanobubble are determined. It is shown that the radius of a stationary nanobubble is equal to the Tolman radius, since at this radius its energy is minimal. The value of the surface charge density and the charge of a vapor nanobubble in water are determined.