Fig. 4 | Nature Communications

Fig. 4

From: How soap bubbles freeze

Fig. 4

Freezing bubbles on a cold stage in a room-temperature environment. a Schematic of the experimental setup, where a bubble of controlled volume is deposited on a frosted Peltier substrate using a syringe pump. b Side-view imaging of freezing bubbles, of volume Ω = 5 μL and Ω = 500 μL on a surface chilled at Tw = −40 ± 1 °C. Arrows indicate the evolving location of the freeze front and time zero is when the bubble is first deposited. c Schematic showing the terms used in Eq. 6. d The frozen arc length of Ω = 500 μL bubbles over time. Data points (circles) represent experimental data, with error bars of one deviation across three trials, while dashed lines represent Eq. 6. e For both Ω = 5 μL (diamonds) and Ω = 500 μL (circles), plotting the frozen arc length normalized by the final arc length (S/Sf) against a nondimensional timescale (t/τf) collapsed all of the data onto a universal curve (Eq. 7). The average ambient conditions across all experiments were T = 23.4 ± 1.2 °C and a relative humidity of RH = 42 ± 14%. f Simulation of the air temperature profile shows that near the center of the Peltier, the bubble somewhat disrupted the natural convection, resulting in greater slopes for the iso-temperature lines (see Supplementary Fig. 8). The dashed line corresponds to T = −6 °C. g Thermographic images of a Ω = 500-μL bubble deposited on a frosted substrate of temperature Tw = −40 ± 1 °C at a room temperature with T = 23.3 ± 1 °C and RH = 23 ± 1.5%

Back to article page