Growth of a vapour bubble in combined gravitational and non-uniform temperature fields

Bubble growth on a flat horizontal superheated wall is studied. Heat flux at the wall is neglected and it is assumed that the influence of the tangential stress condition on the bubble boundary is limited to a thin hydrodynamic boundary layer. Potential flow theory is applied in the liquid outside the bubble. The temperature field is solved separately in a thin thermal boundary layer around the bubble and in the remaining bulk liquid. The boundary condition is obtained by combining the Bernoulli equation for the liquid pressure, the Laplace equation for the surface tension, and the linearized Clapeyron equation. The equations are solved by collocation. The bubble grows because it is blown up and not because liquid is removed by evaporation at the bubble cap. Distortions in the bubble shape can only be due to gravity. Numerical equivalent bubble growth curves are compared with experimental curves. The gross features of the computed data can be fitted to measured data by choosing the initial temperature field suitably.