Vibrating liquids in space
Mazzoni, S., et al. (2010). "Vibrating liquids in space." Europhysics News 41 6: 14-16
Everybody is familiar with the action of gravity on a fluid where density gradients are present due to heating or compositional difference. Due to buoyancy, the denser portions sink to the bottom of the container, pushing away the lighter ones. As a result, convection sets in, transporting heat and mass. In weightlessness conditions, this driving force is absent but inertia exists as the tendency of a body to resist acceleration. When a container filled with liquid is subjected to high frequency vibrations, the fluid is not able to react due to inertia and this may create a flow. If the density is uniform, then the fluid moves as a solid body. However, when density gradient is present, also inertia will not be uniform, resulting in convective motion. Obviously, there is analogy between gravity-induced and inertia-driven convection, as a result of the Einstein equivalence principle, although the second one is almost unknown. What would be the impact of vibration on dispersion by molecular diffusion and heat transfer without buoyancy?