A model for steam bubble formation at a submerged orifice in a flowing liquid.

Abstract

A model for describing steam bubble formation at a submerged orifice in flowing liquid is developed. It is assumed that the bubble grows continuously in the radial direction, translates continuously in the vertical direction, and is surrounded by a thin liquid layer unaffected by the bulk liquid motion. The model allows fluctuation of pressure, temperature, and density of the vapor in a bubble in equilibrium with the liquid at the bubble wall. The temperature profile in the boundary layer is not limited to a quadratic function as assumed in Denekamp’s model6) but varies in accordance with the propagation of heat. The detachment criterion assumed is that the bubble neck is equal to zero for the first bubble of the pairing and equal to half of the bubble radius for the bubble containing the second bubble of the pairing.The prediction values from the present model using an explicit finite-difference technique are compared with experimental data in the literature. The results are in good agreement and show a significant improvement over Denekamp’s model.