In a recent event, researchers have found a property of sand that is only limited to the fluid movements. The sands used in the experiment behaved like oil and water. These two fluids do not mix. The oil stays as a layer over the surface of water due to varying densities. Further this is a property of liquids, and in general, this property is known as immiscibility. This recent discovery expands our horizon and lets us have a reality check on our knowledge about nature.
The experiment was conducted in a controlled environment. The movement of the countless particles has helped us to understand plenty of things and many important conclusions could be derived from the experiment. In the experiment, the scientists saw two varieties of sands among which one performed the bubbles inside the other sand. The applications of the discovery can be many. From pharmaceuticals to construction and maybe even the alternative energy sources, the potential is huge.
As previously told, the experiment was carried out in a controlled environment. There were two types of sand involved in it. While one of the sand was heavy and white, the other sand appeared black and light. The sands were mixed in a see-through rectangular box. The sand in the black colour consisted of larger and lighter grains in comparison to the sand in the white colour. The experiment consisted of a machine that shook the container up and down while the air was blown from the bottom of the container into the sand.
The researchers found the lighter sand particles moving upward in shapes of bubbles and fingers throughout the sand. Many scientists compared it with the Rayleigh-Taylor experiment on fluids. The Rayleigh-Taylor is the kind of behaviour that fluids show in their movement. The lighter liquids move up against, the heavier liquid – the kind of behaviour the oil and water show.
The thing we are dealing with is solid, and hence the Rayleigh-Taylor instability cannot be applied here. What makes the experiment interesting is that the fluids do not mix with no matter whatever the conditions are. But unlike fluids, the sand mixed well with the other particles unless they were subjected to external factors like air pressure and movement.
Various computational models have already been made regarding the experiment. The simulations revealed many important factors. The external air applied to the grains preferred to flow across the lighter grains in comparison to the heavier ones. Combined with external air pressure the lighter particles started moving up. The grain particles in combination with the air pressure and the tendency of heavier particles to move downward, helped the researchers understand the nature of the phenomena. On applying more air pressure, the grains formed the bubble-shaped structures across the grain particles.