Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Diffraction
Wave phenomena can sometimes be a little difficult to wrap one’s head around. In this video, Mike from The Point Studios explains wave diffraction and why opening a window can help you spy on the conversation next door. Diffraction occurs when waves encounter an obstacle. If that obstacle is a slit in a wall, the…
Wingtip Vortices Visualized
In flight, airplane wings produce dramatic wingtip vortices. These vortices reduce the amount of lift a 3D wing produces relative to a 2D one. How much they influence the lift depends on both the strength and proximity of the vortex. The stronger and closer it is, the more detrimental its effect. One way airplane designers…
HIFiRE
Earlier this month, an international team launched a successful hypersonic flight test in Australia. The Hypersonic International Research Experimentation (HIFiRE) Flight 5b was launched atop a two-stage rocket and reached its maximum speed of Mach 7.5, well above Mach 5, which defines the start of the hypersonic regime. The purpose of this particular flight test…
Skating on Vapor
Turn the stove up high enough and you may have noticed that drops of water stop boiling away and instead skate across the surface. This is the Leidenfrost effect, which occurs when a surface is so much hotter than a liquid’s boiling point that any liquid that contacts instantly vaporizes. That thin vapor layer insulates…
Why Does This Kite Look So Real?
A recent viral video features mesmerizing footage of a giant octopus kite flown at a kite festival in Singapore earlier this month. The kite’s arms twist and wave lazily in the breeze. Watching the video, I was struck by how realistic the kite’s motion looks. It really looks like an octopus is just cruising there…
The Reverse Magnus Effect
A good soccer player can kick the ball from the corner of the field into the goal thanks to the Magnus effect. But if you’ve ever tried to play soccer with a smooth ball, you may have noticed that sometimes the ball bends the wrong way! This is the reverse Magnus effect and it’s caused…
How Fluid Dynamics Saved the Space Shuttle
New FYFD video! In which Dianna Cowern (Physics Girl) joins me to explore boundary layer transition and how a couple of small bits of roughness could be a huge problem for the Space Shuttle during re-entry. A lot of people have asked me what I did for my PhD research, and the truth is, I’ve…
Climbing Up the Walls
You may have noticed when baking that fluids don’t always behave as expected when you agitate them. If you put a spinning rod into a fluid, we’d expect the rod to fling fluid away, creating a little vortex that stirs everything around. And for a typical (Newtonian) fluid, this is what we see. The fluid’s…
Bursting Into Droplets
Our atmosphere is full of aerosols – extremely tiny particles and droplets of salt, dust, pollutants, and other substances. Wind’s effects alone cannot account for the sizes and quantities of aerosols we measure. Another potential source is the bursting of bubbles; more specifically, the bubbles that form at the oceans’ surface. Frothy, crashing waves often…
Whiskey Stains
Photographer Ernie Button discovered that whiskey left behind intriguing patterns after it evaporated. Unlike coffee rings, the whiskey leaves behind a more uniform residue. Curious, he contacted researchers at Princeton, who were eventually able to explain why whiskey and coffee dry so differently. They observed three major effects in drying whiskey mixtures. Firstly, the alcohol…