Photographer Mike Olbinski returns with another incredible storm-chasing timelapse video, this time all in black-and-white. To me, that choice helps “Pulse” emphasize the ominous majesty of these supercells and tornadoes by highlighting the textures that make up the clouds. Watching clouds in timelapse, they seem to materialize from nowhere as moisture drawn up from the land cools and condenses. Sped up, suddenly the convective rotation and the roiling turbulence inside clouds is perfectly clear. I especially love the sequence beginning at 2:25, where a distant black line slowly transforms into an incredible landscape marked with successive waves of rolling, turbulent clouds. Watch this one on a large screen at a high resolution, if you can. You won’t regret it! (Video credit: M. Olbinski)
Category: Art
“Kingdom of Colours”
Oil, paint, and soap combine to create a polychrome landscape in Thomas Blanchard’s “Kingdom of Colours” short film. Colorful droplets of paint coated in oil form anti-bubbles that skim along the liquid surface until they burst, dispersing new colors. One of my favorite touches in this video, though, are the branching fingers of color that appear repeatedly (most often in blue-violet). This is an example of a phenomenon known as the Saffman-Taylor instability. It’s a hallmark of a low viscosity fluid pushing into a higher viscosity one–like air into honey. (Image/video credit: T. Blanchard; via Flow Vis)
Creating Moana’s Ocean
Hopefully by now you’ve had an opportunity to see Disney’s film Moana. Fluid dynamics play a central role in the movie, and Disney’s animators faced the challenge of hundreds of shots requiring special effects to animate water, lava, waves, and wind. Science Friday has a great segment interviewing a couple of Moana’s animators, in which they discuss the process of turning the ocean itself into a character.
Because the physics of fluids is so complex, scientists and animators differ in the way they approach simulations. Scientists usually try to capture a full physical representation of a flow, simulating every detail to the smallest scale and time step. Animators, on the other hand, are interested in capturing a realistic feel for a flow. For an animator, the simulation should be exactly as complex as necessary to make the water move in a way a person believes it should. With Moana, animators had the extra challenge of melding the ocean character’s actions with appropriate water physics–think bubbles, drops, and splashes. The results are impressive and exceptionally fun. (Image credits: Disney/Science Friday; via Jesse C.)
Erie Waves
Photographer Dave Sandford braved the cold and turbulent waters of Lake Erie in late fall to capture some remarkable wave action. Like on the ocean, waves in the Great Lakes are largely driven by winds, but lakes don’t develop the constant set of rolling waves that oceans do. Instead their waves are more erratic and unpredictable. Sandford focused on capturing the moment when wind-driven waves coming into shore collided with waves rebounding from piers or rocks along the shore. The results are waves that, through Sandford’s lens, look like exploding mountainsides. Such energetic waves mix sediment and nutrients in the lake, and the spray of droplets can even loft aerosols and pollutants from the water into the atmosphere. (Photo credit: D. Sandford; via Flow Vis)
“Oil Spill”
In “Oil Spill” artist Fabian Oefner explores the shapes and colors of oil floating atop water. An old adage tells us that oil and water don’t mix, but this is not perfectly true. Especially in low concentrations, oil can mix slightly with water, which is why the edges of Oefner’s creations become fuzzy and break down. For the most part, though, the thin layer of oil spreads across the water’s surface, its slight variations in thickness casting the different iridescent colors we observe – just the same as a soap bubble’s iridescence. The colorful patterns are a snapshot of motion in the oil; in some places it radiates outward, pulled by the stronger surface tension of water. In other places it forms plumes and swirls that may be the result of temperature variations or other disquiet motion in the surrounding water or air. (Image credits: F. Oefner)
“Chemical Poetry”
In “Chemical Poetry” artists Roman Hill and Paul Mignot use fluid dynamics to create incredible and engaging visuals. With a stunningly close eye to fluids mixing and chemicals reacting, their imagery feels like gazing on primordial acts of creation or destruction. There’s even a sequence that feels like you’re watching an explosion in slow-motion, but there’s no CGI in any of it. This is just the beauty of physics laid bare, revealing the dances driven by surface tension, the undulations of a fluid’s surface, and the dendritic spread of one fluid into another – all cleverly lit and filmed for maximum effect. It is well worth taking the time to watch the whole video and check out more of their work. (Image/video credit and submission: NANO; GIFs via freshphotons)
Colors in Macro
Milk, acrylic paints, soap, and oil – all relatively common fluids, but together they form beautiful mixtures worth leaning in to enjoy. Variations in surface tension between the liquids cause much of the motion we see. Soap, in particular, has a low surface tension, which causes nearby colors to get pulled away by areas with higher surface tension, behavior also known as the Marangoni effect. Adding oil creates some immiscibility and lets you appreciate both the coalescence and fragmentation of the fluids. And finally, there’s one of my favorite sequences, where bubbles start popping in slow motion. As the bubble film ruptures, fluid pulls away, breaking into ligaments and then a spray of droplets as the bubble disintegrates. (Video credit: Macro Room; via Gizmodo)
Swirling Pollen
This photo captures the chaotic mixing present in a simple puddle. Pine pollen strewn across the puddle’s surface acts as tracer particles, revealing some of the motion of the underlying water. As wind blows across the puddle, it moves the water through the formation of ripples and by shearing the surface. That deformation on the top of the puddle will cause further motion beneath the surface. With time and changing wind direction, the resulting pattern of flow can be very complex! (Photo credit: K. Jensen, original)
“Gargantua”
Peering into a vortex feels like staring into an abyss in the Julia Set Collective’s “Gargantua”. Like their previously featured works, this video uses a macro perspective on fluid phenomenon to create an alternate sense of scale. Instead of a whirlpool, we could be observing a wormhole. Part of this is a matter of fooling our brains with perspective, but it also works because, on some level, we recognize that these same fluid patterns occur at very different lengthscales and so it is believable that what we see is much bigger than in reality. (Video credit and submission: S. Bocci/Julia Set Collective)
Inside a Cello
At first glance, Adrian Borda’s photograph seems to show an old room. In reality, this is the interior of a cello with light shining through the f-holes. Dust particles in the air trace out pathlines that reveal the turbulent movements of air inside the instrument. Both the camera’s perspective and the visible flow try to trick our minds into seeing something larger than reality. It’s a reminder that the patterns and forms of fluid flow repeat across an enormous range of scales, from millimeters to light-years. (Image credit: A. Borda; via Joseph S./CU Boulder Flow Viz)
