The behavior of champagne bubbles could lead to new breakthroughs in the energy industry.
When a bottle of champagne is uncorked the pressure of the liquid rapidly escapes, and the bubbles undergo a "coarsening" process in which larger bubbles grow at the expense of smaller ones, the American Institute of Physics reported. The phenomenon, known as "Ostwald ripening," could be used in scientific systems such as "spin systems, foams and metallic alloys."
Ostwald ripening can also be observed in power-generating turbines, which involve highly-complex bubbling processes that are not completely understood by science. In order to gain insight into this process using simulations made by the K computer at RIKEN. In these simulations virtual molecules are assigned initial velocities, and researchers watch how they continue moving through Newton's law of motion.
"A huge number of molecules, however, are necessary to simulate bubbles -- on the order of 10,000 are required to express a bubble," Hiroshi Watanabe, a research associate at the University of Tokyo's Institute for Solid State Physics. "So we needed at least this many to investigate hundreds of millions of molecules -- a feat not possible on a single computer."
The researchers simulated an impressive 700 million particles, and followed their motion through a million timed steps. The team believed the feat was the first simulation is the first to look at multi-bubble nuclei without relying on artificial conditions.
"In the past, while many researchers wanted to explore bubble nuclei from the molecular level, it was difficult due to a lack of computational power," explained Watanabe. "But now, several petascale computers -- systems capable of reaching performance in excess of one quadrillion point operations per second -- are available around the world, which enable huge simulations."
The team found the time evolution of the bubbles can be described through a 1960s mathematical framework called "LSW theory" that has never before been used to describe gas bubbles in liquid.
"While the nucleation rate of droplets in condensation is well predicted by the classical theory, the nucleation rates of bubbles in a superheated liquid predicted by the theory are markedly different from the values observed in experiments," Watanabe said. "So we were expecting the classical theory to fail to describe the bubble systems, but were surprised to find that it held up."
Gaining insight into the behavior of bubbles could have important implications in the field of engineering, and could lead to the development of more efficient power stations and propellers.
The findings were published in a recent edition of The Journal of Chemical Physics.
