#vorticity — Public Fediverse posts

Recreating Atmospheres

In planetary atmospheres, energy and vorticity can cascade from large scales to smaller ones, but the mechanics of this transfer remain somewhat elusive. In a recent experiment, researchers built a lab-scale representation of an atmosphere using a meter-scale rotating annular tank. The outer bottom edge of the tank gets heated–representing the sun’s warming at the equator–while a pipe in the center of the tank gets cooled near the tank surface, which mimics the chilling effect of the poles. Researchers filled the tank with a water-glycerol mixture and recorded how their artificial atmosphere responded at different rotation rates.

The results show an energy spectrum that’s consistent with atmospheric observations–with a steep drop at large length scales and a flatter one at smaller scales. But interestingly, they also found that the cascade was temperature-dependent in ways that current models don’t predict. Untangling that effect could help us understand not only our atmosphere but those of other planets. (Image credit: tank – H. Scolan, animation – S. Ding et al.; research credit: S. Ding et al.; via APS)

Recreating Atmospheres

In planetary atmospheres, energy and vorticity can cascade from large scales to smaller ones, but the mechanics of this transfer remain somewhat elusive. In a recent experiment, researchers built a lab-scale representation of an atmosphere using a meter-scale rotating annular tank. The outer bottom edge of the tank gets heated–representing the sun’s warming at the equator–while a pipe in the center of the tank gets cooled near the tank surface, which mimics the chilling effect of the poles. Researchers filled the tank with a water-glycerol mixture and recorded how their artificial atmosphere responded at different rotation rates.

The results show an energy spectrum that’s consistent with atmospheric observations–with a steep drop at large length scales and a flatter one at smaller scales. But interestingly, they also found that the cascade was temperature-dependent in ways that current models don’t predict. Untangling that effect could help us understand not only our atmosphere but those of other planets. (Image credit: tank – H. Scolan, animation – S. Ding et al.; research credit: S. Ding et al.; via APS)

Recreating Atmospheres

In planetary atmospheres, energy and vorticity can cascade from large scales to smaller ones, but the mechanics of this transfer remain somewhat elusive. In a recent experiment, researchers built a lab-scale representation of an atmosphere using a meter-scale rotating annular tank. The outer bottom edge of the tank gets heated–representing the sun’s warming at the equator–while a pipe in the center of the tank gets cooled near the tank surface, which mimics the chilling effect of the poles. Researchers filled the tank with a water-glycerol mixture and recorded how their artificial atmosphere responded at different rotation rates.

The results show an energy spectrum that’s consistent with atmospheric observations–with a steep drop at large length scales and a flatter one at smaller scales. But interestingly, they also found that the cascade was temperature-dependent in ways that current models don’t predict. Untangling that effect could help us understand not only our atmosphere but those of other planets. (Image credit: tank – H. Scolan, animation – S. Ding et al.; research credit: S. Ding et al.; via APS)

Recreating Atmospheres

In planetary atmospheres, energy and vorticity can cascade from large scales to smaller ones, but the mechanics of this transfer remain somewhat elusive. In a recent experiment, researchers built a lab-scale representation of an atmosphere using a meter-scale rotating annular tank. The outer bottom edge of the tank gets heated–representing the sun’s warming at the equator–while a pipe in the center of the tank gets cooled near the tank surface, which mimics the chilling effect of the poles. Researchers filled the tank with a water-glycerol mixture and recorded how their artificial atmosphere responded at different rotation rates.

The results show an energy spectrum that’s consistent with atmospheric observations–with a steep drop at large length scales and a flatter one at smaller scales. But interestingly, they also found that the cascade was temperature-dependent in ways that current models don’t predict. Untangling that effect could help us understand not only our atmosphere but those of other planets. (Image credit: tank – H. Scolan, animation – S. Ding et al.; research credit: S. Ding et al.; via APS)

Recreating Atmospheres

In planetary atmospheres, energy and vorticity can cascade from large scales to smaller ones, but the mechanics of this transfer remain somewhat elusive. In a recent experiment, researchers built a lab-scale representation of an atmosphere using a meter-scale rotating annular tank. The outer bottom edge of the tank gets heated–representing the sun’s warming at the equator–while a pipe in the center of the tank gets cooled near the tank surface, which mimics the chilling effect of the poles. Researchers filled the tank with a water-glycerol mixture and recorded how their artificial atmosphere responded at different rotation rates.

The results show an energy spectrum that’s consistent with atmospheric observations–with a steep drop at large length scales and a flatter one at smaller scales. But interestingly, they also found that the cascade was temperature-dependent in ways that current models don’t predict. Untangling that effect could help us understand not only our atmosphere but those of other planets. (Image credit: tank – H. Scolan, animation – S. Ding et al.; research credit: S. Ding et al.; via APS)

Explaining the Swirl of Wildfire Smoke

In recent years, smoke from powerful wildfires has raised questions among atmospheric scientists by always swirling in the same direction. The confounding structures were observed in the stratosphere, where smoke injected at around 15 kilometers in altitude absorbed sunlight and rose further, up to about 35 kilometers of altitude. The rising column of fluid would stretch, causing any residual rotation to get stronger and form vortices.

None of this was a surprise. What was surprising is that all of the observed vortices were anticyclones, when theory–at least for a heat-driven vortex from a stationary heating source–called for a cyclone-anticyclone pair.

Researchers looked at how a self-heating (and, therefore, moving) source would rotate. They concluded that this, too, would create a pair of vortices–one cyclonic and one anticyclonic–but the anticyclone would be stronger than the cyclone that trailed behind it. By further considering the vertical shear the vortex pair would encounter, the researchers found that the trailing cyclone could get stripped away, leaving behind only the anticyclone–matching our wildfire observations. (Image credit: J. Stevens/NASA Earth Observatory; research credit: K. Shah and P. Haynes 1, 2; via APS)

Explaining the Swirl of Wildfire Smoke

In recent years, smoke from powerful wildfires has raised questions among atmospheric scientists by always swirling in the same direction. The confounding structures were observed in the stratosphere, where smoke injected at around 15 kilometers in altitude absorbed sunlight and rose further, up to about 35 kilometers of altitude. The rising column of fluid would stretch, causing any residual rotation to get stronger and form vortices.

None of this was a surprise. What was surprising is that all of the observed vortices were anticyclones, when theory–at least for a heat-driven vortex from a stationary heating source–called for a cyclone-anticyclone pair.

Researchers looked at how a self-heating (and, therefore, moving) source would rotate. They concluded that this, too, would create a pair of vortices–one cyclonic and one anticyclonic–but the anticyclone would be stronger than the cyclone that trailed behind it. By further considering the vertical shear the vortex pair would encounter, the researchers found that the trailing cyclone could get stripped away, leaving behind only the anticyclone–matching our wildfire observations. (Image credit: J. Stevens/NASA Earth Observatory; research credit: K. Shah and P. Haynes 1, 2; via APS)

Explaining the Swirl of Wildfire Smoke

In recent years, smoke from powerful wildfires has raised questions among atmospheric scientists by always swirling in the same direction. The confounding structures were observed in the stratosphere, where smoke injected at around 15 kilometers in altitude absorbed sunlight and rose further, up to about 35 kilometers of altitude. The rising column of fluid would stretch, causing any residual rotation to get stronger and form vortices.

None of this was a surprise. What was surprising is that all of the observed vortices were anticyclones, when theory–at least for a heat-driven vortex from a stationary heating source–called for a cyclone-anticyclone pair.

Researchers looked at how a self-heating (and, therefore, moving) source would rotate. They concluded that this, too, would create a pair of vortices–one cyclonic and one anticyclonic–but the anticyclone would be stronger than the cyclone that trailed behind it. By further considering the vertical shear the vortex pair would encounter, the researchers found that the trailing cyclone could get stripped away, leaving behind only the anticyclone–matching our wildfire observations. (Image credit: J. Stevens/NASA Earth Observatory; research credit: K. Shah and P. Haynes 1, 2; via APS)

Playful Martian Dust Devils

The Martian atmosphere lacks the density to support tornado storm systems, but vortices are nevertheless a frequent occurrence. As sun-warmed gases rise, neighboring air rushes in, bringing with it any twisted shred of vorticity it carries. Just as an ice skater pulling her arms in spins faster, the gases spin up, forming a dust devil.

In this recent footage from the Perseverance Rover, four dust devils move across the landscape. In the foreground, a tiny one meets up with a big 64-meter dust devil, getting swallowed up in the process. It’s hard to see the details of their crossing, but you can see other vortices meeting and reconnecting here. (Video and image credit: NASA/JPL-Caltech/LANL/CNES/CNRS/INTA-CSIC/Space Science Institute/ISAE-Supaero/University of Arizona; via Gizmodo)

#atmosphericScience #conservationOfAngularMomentum #dustDevils #fluidDynamics #Mars #physics #science #vorticity

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

#astrophysics #blackHole #fluidDynamics #physics #quantumVortex #science #superfluid #superfluidHelium #vortices #vorticity

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

#astrophysics #blackHole #fluidDynamics #physics #quantumVortex #science #superfluid #superfluidHelium #vortices #vorticity

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

#astrophysics #blackHole #fluidDynamics #physics #quantumVortex #science #superfluid #superfluidHelium #vortices #vorticity

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

#astrophysics #blackHole #fluidDynamics #physics #quantumVortex #science #superfluid #superfluidHelium #vortices #vorticity

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

#astrophysics #blackHole #fluidDynamics #physics #quantumVortex #science #superfluid #superfluidHelium #vortices #vorticity

Towards Multi-spatiotemporal-scale Generalized PDE Modeling

Jayesh K Gupta, Johannes Brandstetter

Action editor: Vikas Sindhwani.

https://openreview.net/forum?id=dPSTDbGtBY

#vorticity #convolution #deep

Towards Multi-spatiotemporal-scale Generalized PDE Modeling

Jayesh K Gupta, Johannes Brandstetter

Action editor: Vikas Sindhwani.

https://openreview.net/forum?id=dPSTDbGtBY

#vorticity #convolution #deep

Towards Multi-spatiotemporal-scale Generalized PDE Modeling

Jayesh K Gupta, Johannes Brandstetter

Action editor: Vikas Sindhwani.

https://openreview.net/forum?id=dPSTDbGtBY

#vorticity #convolution #deep

I know, I know, we have LaTeX support, but I'm a fountain pen guy. #Vorticity #Poloidal #Toroidal

I know, I know, we have LaTeX support, but I'm a fountain pen guy. #Vorticity #Poloidal #Toroidal

I know, I know, we have LaTeX support, but I'm a fountain pen guy. #Vorticity #Poloidal #Toroidal

I know, I know, we have LaTeX support, but I'm a fountain pen guy. #Vorticity #Poloidal #Toroidal

I know, I know, we have LaTeX support, but I'm a fountain pen guy. #Vorticity #Poloidal #Toroidal