Recent progress in axisymmetric drop shape analysis (ADSA)

Area of Science:

• Surface science and interfacial phenomena
• Physical chemistry and materials science
• Computational physics and numerical analysis

Background:

• Axisymmetric Drop Shape Analysis (ADSA) is a key technique for measuring interfacial properties using drop/bubble shapes.
• Existing ADSA methods show inconsistencies, particularly for nearly spherical drop shapes, with limitations not fully understood.
• The quality of digital images significantly impacts surface tension measurement accuracy.

Purpose of the Study:

• To systematically scrutinize the entire ADSA technique, including hardware and software, to identify and address limitations.
• To enhance the accuracy and reliability of interfacial property measurements obtained through ADSA.
• To develop objective criteria for defining the applicability of ADSA, especially for challenging drop shapes.

Main Methods:

• Developed guidelines for hardware component usage to improve digital image quality.
• Introduced a versatile image analysis module with a robust edge detection technique.
• Implemented a more efficient numerical scheme and introduced a quantitative 'shape parameter' to assess drop sphericity.

Main Results:

• Enhanced image quality guidelines improve the foundation for ADSA measurements.
• The improved software and numerical scheme offer more accurate interfacial property determination.
• The newly introduced shape parameter quantifies the range of ADSA applicability and predicts result accuracy.

Conclusions:

• Systematic scrutiny and improvement of ADSA hardware and software enhance measurement accuracy.
• The shape parameter provides an objective criterion for ADSA's range of applicability and a priori accuracy assessment.
• The refined ADSA technique offers more reliable interfacial property measurements, especially by addressing limitations with near-spherical shapes.