Pendant Drop Method for Interfacial Tension Measurement

The basic principle of pendant drop method used for interfacial tension measurement is stated.It mainly links pendant drop interface profile with corresponding parameters,such as density difference,gravity and surface tension,and with hydrodynamic statics.The surface tension is then deduced according to the measured surface profile.Based on above results,a system for liquid interfacial tension measurement was developed,and correlative data processing software that can calculate the interfacial tension from edge detection manually was also incorporated.Extensive experiments were carried out to evaluate the accuracy and applicability of the proposed system in interfacial tension measurement.Experimental results of water and pure ethanol solution show that for low viscosity liquids,the pendant drop method presents significant characteristics such as simple,accuracy,low cost and good agreement with theoretical prediction,so it's extremely suitable for measurement in laboratory.