Hydrodynamic processes in dynamic bubble pressure experiments .1. A general analysis

The transition of the bubble lifetime in maximum bubble pressure experiments to milliseconds and submilliseconds can be arranged by decreasing the capillary length. In this time range, a transitional hydrodynamic regime results with spatial inhomogeneities of the gas flow. As a consequence, a considerable increase of the calculated deadtime of a growing bubble can be expected as compared to the Poiseuille regime. An equation has been derived and discussed qualitatively for estimating the bubble lifetime and a correction Delta t(d) to the deadtime. The given approach neglects the variation of surface tension during the bubble growth, and the growth of the bubble is assumed to be purely hydrodynamic. Also, surfactant adsorption accompanied by a decrease in capillary pressure was not considered in the present approach.