Bubble interactions in liquid/gas flows

Abstract. The system of equations, usually employed for unsteady liquid/gas flows, has complex characteristics. This as wellas other facts have led to the search for a more accurate description of effects associated with relative motion. F r liquid/bubble systems the fluctuations resulting from hydrodynamic interaction between the bubbles may be taken into account in the same way as particle interactions i the theory of viscous suspensions. This is illustrated for the pressure. In a description accurate up till the third power of the void fraction two-bubble interactions are f primary importance. Numerically obtained results for the relative motion in bubble pairs are presented an interpreted with help of simplified equations from which conclusions can be draw in an analytic way. 1