The effects of viscosity on the behaviour of bubbles in viscous liquids

Abstract

Numerical algorithms were developed to solve the basic equations describing growth or dissolution of bubbles in viscous liquids both for isothermal behaviour or variable temperature. Growth and dissolution of gas bubbles in viscous liquids cause changes in concentration inside the bubble and in the liquid at equilibrium with the gas phase, and these changes also affect the dynamics of bubble behaviour. Simple criteria are provided to assess when the role of viscosity is significant, due to slow viscous relaxation. The growth or dissolution of carbon dioxide bubbles and oxygen bubbles in soda-lime-silicate glasses has been chosen to demonstrate the main features of isothermal bubble behaviour and the changes that occur as glass samples are cooled from fining temperature to room temperature at several cooling rates. The predicted changes in size and concentration inside the bubbles stop at about 100-150°C above the glass annealing temperature for typical cooling rates