Investigating Effects of Concentration, Angle, Diameter and Impact Velocity of Soap Film and Soap Droplet on Trajectory of Droplet

Abstract

Soap is an essential item in our lives for housekeeping and has a variety of applications, including the making of soap films. Soap films are known for their ability to filter particles by size, but little research is done about soap films in the shape of a bubble (soap bubbles), and how soap droplets interact with it. A 0.05 mL soap droplet dropped onto the soap bubble under different sets of conditions. Our experiment aims to investigate the factors that determine whether a soap droplet dropped onto the soap bubble passes through or is deflected off the soap bubble. After collecting our experimental data, we used machine learning for modelling. Predictions for points in the range of experimental conditions (width 2–12 cm, distance 1–19 cm, angle 45°, 60°, 90° and concentration of soap droplet and bubble 4% and 6%) were generated. Our experiment demonstrates that independent factors such as greater height width, impact velocity and angle have a positive correlation with penetration. Our findings also show that a concentration of 6% w/w droplet and 4% w/w bubble provided the most significant probability of penetration. Such findings are all aligned with our hypothesis, based on our knowledge on the matter. Soap films have a hydrophilic head and a hydrophobic tail, just like our cell membranes. By diving deeper into fluid mechanics and providing a model of this experimental design, our work may provide insights on the movement of molecules through our biological cells, which may be useful for future generations of engineers and biologists.