Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Phase-Switching to Avoid Icing
Preventing ice and frost from forming on surfaces – especially airplane wings – is a major engineering concern. The chemical de-icing cocktails currently used in aviation are a short-lived solution, and while superhydrophobic surfaces can be helpful, they tend to be easily damaged and therefore impractical. Another possible solution, shown here, are so-called phase-switching liquids…
Agnes Pockels: Surface Science Pioneer
Today’s FYFD video tells a story I’ve wanted to share for a couple of years now. It’s about the life and work of Agnes Pockels, a woman born in the mid-nineteenth century who, despite a lack of formal scientific training, made major contributions to the understanding of surface tension and to the experimental apparatuses and…
The Color of Droplets
In nature, color comes from many sources: like the pigmentation of skin and hair, the structural iridescence of a butterfly’s wings, or the refraction of a rainbow from water droplets. Recently, scientists discovered another source of brilliant color in simple, hemispherical water droplets. When small droplets form on a transparent surface, they form concave shapes…
Weirs
Hydraulic engineers use weirs, like the one shown below, to control upstream flow conditions. Weirs can come in many forms, but they essentially look like a small dam with water flowing over the top. They’re used to control both the flow rate and the upstream water level. As Grady from Practical Engineering explains, there are…
Forming a Waterfall
Many factors can affect a waterfall’s formation – changes in bedrock structure, tectonic shifts, and glacial motion, to name a few. But a new study suggests that some waterfalls may be self-forming. Using a lab-scale experiment, researchers created a homogeneous “bedrock” out of polyurethane foam, which they eroded with a combination of constant water flow and…
Water Impacts
In the clean and simplified world of the laboratory, a droplet’s impact on water is symmetric. From a central point of impact, it sends out a ring of ripples, or even a crown splash, if it has enough momentum. But the real world is rarely so simple. Here we see how droplets impact when the…
Rogue Waves
After centuries of tales from sailors, in 1995 the Draupner off-shore platform recorded the first ever evidence of a freak wave – a single, wall-like wave steeper and taller than any other waves around it. Theories have been tossed back and forth for the last quarter century as to how the Draupner wave formed, but…
Moving Droplets
Microfluidic devices – such as those used by individuals with diabetes to monitor their blood glucose levels – are all about transport. Typically, these devices use some kind of externally applied force, like a temperature gradient or electrical field, to force liquids through the device’s narrow channels. But a new study describes a way to…
Freezing Drop Impact
At the altitudes where aircraft fly, it’s often cold enough for water drops to freeze in seconds or less. Once attached to a wing, such frozen drops disrupt the flow, reducing lift and increasing drag. To help understand how such droplets freeze, scientists study droplet impact on cold surfaces. Starting at room temperature (counter-clockwise from…
Sniffing
In many ways, smell is a strange sense. The very act of sniffing – pulling air and odor molecules into our noses – changes what remains behind in a way that sight and sound do not. Humans aren’t great sniffers, but dogs have an exquisite sense of smell, and in this video, Deep Look describes…