Biomedical subjects

Alberto Tufaile

Publications and source records attributed to Alberto Tufaile.

4 recordsLinked to original sources

PubMed2006

Champagne experiences various rhythmical bubbling regimes in a flute.

Bubble trains are seen rising gracefully from a few points on the glass wall (called nucleation sites) whenever champagne is poured into a glass. As time passes during the gas-discharging process, the careful observation of some given bubble columns reveals that the interbubble distance may change suddenly, thus revealing different rhythmical bubbling regimes. Here, it is reported that the transitions between the different bubbling regimes of some nucleation sites during gas discharging is a process which may be ruled by a strong interaction between tiny gas pockets trapped inside the nucleation site and/or also by an interaction between the tiny bubbles just blown from the nucleation site.

Carbon Dioxide↗

PubMed2005

Period-adding route in sparkling bubbles.

Chains of bubbles are seen rising along the wall whenever champagne is poured into a glass. The careful observation of a given bubble chain often reveals that the interbubble distance suddenly changes during the degassing process, indicating different bubbling regimes in this elusive phenomenon of effervescence. We report the transitions between these different bubbling regimes that present sequences of multiple periods known as the period-adding route.

Journal Article↗

PubMed2004

Bistability in bubble formation.

We obtain experimental data on time intervals of a bubble train generated from a nozzle with the air flow rate as the control parameter. Varying the length of the hose that connects the proportionating solenoid valve to the nozzle, we generate bifurcation diagrams showing period-adding cascades, among other dynamical phenomena. Then we construct a two-parameter family of one-dimensional maps whose bifurcation diagrams qualitatively match the experimental ones. The model indicates the existence of parameters where two attractors coexist, a phenomenon called bistability, and the same behavior is fully confirmed in the experiment.

Journal Article↗

PubMed2004

Period-adding bifurcations and chaos in a bubble column.

We obtained period-adding bifurcations in a bubble formation experiment. Using the air flow rate as the control parameter in this experiment, the bubble emission from the nozzle in a viscous fluid undergoes from single bubbling to a sequence of periodic bifurcations of k to k+1 periods, occasionally interspersed with some chaotic regions. Our main assumption is that this period-adding bifurcation in bubble formation depends on flow rate variations in the chamber under the nozzle. This assumption was experimentally tested by placing a tube between the air reservoir and the chamber under the nozzle in the bubble column experiment. By increasing the tube length, more period-adding bifurcations were observed. We associated two main types of bubble growth to the flow rate fluctuations inside the chamber for different bubbling regimes. We also studied the properties of piecewise nonlinear maps obtained from the experimental reconstructed attractors, and we concluded that this experiment is a spatially extended system.

Journal Article↗