Fluid dynamics can be quite bizarre, and scientists are still trying to understand what causes various liquids to create predictable (and unpredictable) patterns. University of Cambridge engineer Sungjune Jung shows us how jets of liquid water, over time, can be made to transform from a sheer sheet of water into a beautiful "fishbone" pattern.
This video shows the evolution of the flow structures generated from the collision of two liquid jets each with a radius of 420um. The jets were ejected from parallel cylindrical nozzles with an internal diameter of 0.85mm.
The collision of the jets resulted in various systems of behaviour which depend on the jet velocities and the liquid properties. We focus on the system where the impinging jets form a liquid sheet which then breaks up into a regular succession of ligaments and droplets, a so-called "fishbone" pattern. This high-speed imaging reveals a fish-like formation for the fluid: the oval sheet with rims correspond to the fish head, the drops on thin ligaments to its body, and bigger free drops at the end to its tail. We are particularly interested in this fluid formation, because the fishbone phenomenon provides a simple and visual tool to evaluate the properties of inkjet printing fluids, with which the fishbone structure sensitively varies.
Many thanks to Prof Ian Hutchings, Dr Graham Martin and Dr Steve Hoath at Inkjet Research Centre, Department of Engineering.
Music by Intercontinental Music Lab
This is the eleventh in a series of videos called Under the Microscope, which io9 is posting in partnership with scientists at University of Cambridge. Under the Microscope is a collection of videos that capture glimpses of the natural and artificial world in stunning close-up. They will be released every Monday and Thursday for the next couple of months, and you can see the whole series here.