Formation of soap bubbles by gas jet

Abstract

Soap bubbles can be easily generated by varies methods, while their formation process is complicated and still worth study. A model about the bubble formation process was proposed in Phys. Rev. Lett. 116, 077801 recently, and it was reported that the bubbles were formed when the gas blowing velocity was above one threshold. However, after repeating these experiments, we found the bubbles could be generated in two velocities ranges which corresponded to laminar and turbulent gas jet respectively, and the predicted threshold was only effective for turbulent gas flow. The study revealed that the bubble formation was mainly influenced by the aerodynamics of the gas jet blowing to the film, and these results will help to further understand the formation mechanism of the soap bubble as well as the interaction between gas jet and thin liquid film.

Blowing big bubbles

“…Interestingly Zhou et al, 19 using an experimental setup similar to Salkin's, have observed the opposite of our findings: smaller bubbles at lower air speeds, larger at higher speeds and a regime between in which no bubbles are observed. However, their air speeds (as characterised by the Reynolds number) are slower than ours, meaning that their no-bubble regime may correspond with our almost closed bubbles regime.…”

Dynamics and morphology of droplet penetrating a soap film

“…For example, Huibers & Shah (1997) determined the thickness of the soap film by using the multispectral method and found that the thickness of the soap film varied over four orders of magnitude, from less than 5 nm to greater than 50 μm, depending on the spectral range and accuracy of the spectrophotometer. Quantitative analysis on the conditions, criteria and main features of soap bubble formation has been extensively performed recently, both experimentally and theoretically (Dong et al 2014;Panizza & Courbin 2016;Salkin et al 2016;Davidson & Ryu 2017;Zhou et al 2017), while creation of soap bubbles through various methods has also received attention. For example, Frazier, Jiang, & Burton (2020) highlighted the process of making giant bubbles, while Zang et al (2018) generated bubbles from droplets using ultrasound resonance.…”