One of the things sedimentologists try to do is visualize how individual grains behave. This is important for things like sediment transport and deposition - it even plays an important role in things like quicksand. In some cases, it's helpful to scale a system down so that it may be observed in a lab room, under manageable timescales. I've been working on scaling things up to look at how individual grains interact with each other. A few thousand fluorescent BBs and a blacklight help bring out the details look pretty interesting with a long-exposure photograph.
Very interesting (and beautiful). Reminds me of elegant scaling up experiments on insect wings in which mineral oil was used to simulate air and keep Reynolds number similitude: e.g. http://plus.maths.org/issue17/news/bumble/index.html
ReplyDeleteCool pic! Where do you get a few thousand fluorescent BBs from?
ReplyDeleteAydin,
ReplyDeleteThey're "airsoft" gun bb's - they sell them in packs of several thousand. They come in many colors, including a few nicely fluorescent ones. I think they may be a better choice than metal BBs for some photography needs, too (well, perhaps a different color than blaze orange).