Wednesday, May 18, 2011

Some particles are able to flow up small waterfalls, physicists show

Cuban physicists discover some particles are able to flow up small waterfalls

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With just a small bit of research, the team was able to show what seems to be counterintuitive; that it truly is possible for some(and some of the liquid itself) to travel up a very small waterfall and into the reservoir behind it. While most anyone that has observedhas likely noted the whirls and eddies that form when water tries to flow along or past obstacles, it’s difficult to imagine such counter-flows being created with sufficient force to actually push the fluid uphill. Althsuler et al. show that in fact, it can.

To see what was going on, they used two lab containers; one to hold the room temperature water, the other to hold the chalk they used instead of mate leaf bits (figuring it would be much easier to follow with the naked eye). They then placed an open half-cylinder shapedbetween the two containers that would allow water to flow smoothly from the first container down the channel, where it would then drop into the second container. With this setup, they discovered that as the liquid came rushing down the channel, the main mass oftraveled down the center, creating vortices that caused small amounts of fluid to travel along the edges of the channel in the opposite direction, allowing the chalk to work its way up to the higher level container. But, they also discovered by varying the height of the channel, that it only occurred when the dropping distance was very slight; in this case, 1 centimeter, or less.

As a result of this study, it’s likely that certain industrial processes might have to be modified to make certain unintentional contamination doesn’t occur that is currently being overlooked. Also, its likely future research on thiswill need to be done to determine if other factors can affect the height of the fall or the amount of particulate that is able to travel uphill to another vessel.


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