New development in processing pendant droplet tensiometry data

A database linking the dimensionless volume of pendant droplets V-pen and the dimensionless volume of the spherical caps at the apex of the droplets V-cap has been constructed from the governing equations of pendant droplet tensiometry. The Bond number Bo that relates surface tension to gravitational body force appears as an independent parameter in this database. Computing V-pen and V-cap from the measured profile of a droplet and making use of the database allow the prevailing Bo to be determined and surface tension to be calculated. This new way of converting measured profiles into surface tension has a number of advantages, such as reliability and simplicity, compared to existing methods. These are demonstrated by applying the new method to a number of measured profile data taken from the literature.