The discussion focuses on measuring the contact angle between immiscible liquids in a tube, highlighting the lack of literature on the subject. Key methods suggested include using a profile projector (optical comparator) and employing optical or ultrasonic sensors. The process involves advancing the sensor along the tube's axis to identify the point where the contact annulus reflects back to the sensor, while blocking direct axial reflections. Accurate measurements can be achieved using a micrometer or an LVDT to determine the sensor's position.
PREREQUISITESResearchers in fluid dynamics, engineers working with immiscible liquids, and laboratory technicians involved in contact angle measurements will benefit from this discussion.