Interesting Images

As a keen photographer, I always like to see images of research that can capture the attention of an audience. I thought I would share a few striking images that I've come across that relate to micro flows…

The first image above was produced by researchers at MIT and the Weizmann Institute of Science (WIS). They found that the movements of hair-like cilia on corals actually help draw in nutrients to the coral and drive away waste by creating vortical flows at the surface. More information on this work (and an interesting video) can be found in the article 'Nature's Tiny Engineers':

We know that the manipulation of drops could be useful in a variety of applications, for example in the pharmaceutical or food industries. The second image comes from a research poster produced by Weyer et al. of the University of Liege. The poster describes a simple method for building a complex drop using a crosswise array of fiber: essentially, a large drop of oil runs down the vertical fiber and encapsulates individual dyed water drops at each intersection. The poster itself can be found at:

The third and final image shows a prototype of a ferrofluid ion thruster. Researchers from Michigan Technological University have proposed the use of ferrofluids (which consist of a carrier liquid and ferrous nanoparticles and so are magnetically sensitive) in microspray thrusters that could be used to propel nanosatellites. A magnetic field is applied to a ring of ferrofluid on the thruster surface to create the ferrofluid's characteristic spikes –  thrust is then created by the jets of ferrofluid that spray out from the tip of each spike when an electric force is applied. Compared with typical microspray thrusters that spray jets of liquid through hollow needle-like structures, the ferrofluid thruster is considerably more robust. More information can be found at: