#turbulence — Public Fediverse posts

Weekly Update from the Open Journal of Astrophysics 08/08/2026

Although it’s holiday season for some, it’s time once more for another Saturday update of activity at the Open Journal of Astrophysics. Since the last update we have published a further four papers, bringing the number in Volume 9 (2026) to 167 and the total so far published by OJAp up to 615.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week was published on Tuesday 4th August in the folder Astrophysics of Galaxies with the title “Small-scale turbulence alongside large-scale turbulence in a z=1.87 star-forming galaxy with an outflowing wind, revealed by multi-point structure functions” by Itzhak Goldman (Afeka College, Israel). A previous study by the author found evidence of large and small scale turbulence in the star-forming galaxy CSWA13, suggesting that star clusters and large clumps within the galaxy could be driving this turbulence.

The overlay for this paper is here

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117036181269903989

The second paper for this week, published on Thursday 6th August in the folder Astrophysics of Galaxies, is “From Clumps to Sheets: Geometry Controls the Temperature PDF of Multi-Phase Gas” by Zirui Chen and S. Peng Oh (UC Santa Barbara, USA). This study uses 3D hydrodynamic simulations to show that the temperature probability distribution functions (PDFs) of multi-phase turbulent gas differ significantly under interstellar medium (ISM) and circumgalactic medium (CGM) conditions.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047322340826393

The third paper of the week, published on Thursday 6th August in folder Instrumentation and Methods for Astrophysics is “First Detection of Extensive Air Showers Using a Small-Aperture Fluorescence Telescope” by M. Zotov (M.V. Lomonosov Moscow State University, Russia) and 7 others based in Russia and Armenia. The study reports the first-ever detection of extensive air showers from ultra-high-energy cosmic rays using a compact fluorescence telescope, employing both conventional and deep learning analysis methods.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047408583672745

The fourth and final paper of the week was published on Friday 7th August in the folder Cosmology and Nongalactic Astrophysics: “TDCOSMO XXVI: Uniform Lens Modeling of Eight Doubly Imaged Quasars“, by Ryan Brady (Stony Brook University, USA) and 9 others based all around the world, presents a new method for analyzing doubly imaged quasars using the Hubble Space Telescope, revealing that arc surface brightness is key to precision in mass model measurements.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117053056092162466

That’s all for this week. We have about a dozen more papers accepted and waiting for the authors to put the final version on arXiv, which they will presumably do when they’re back from holiday. I’ll do an update next weekend and we’ll see!

Weekly Update from the Open Journal of Astrophysics 08/08/2026

Although it’s holiday season for some, it’s time once more for another Saturday update of activity at the Open Journal of Astrophysics. Since the last update we have published a further four papers, bringing the number in Volume 9 (2026) to 167 and the total so far published by OJAp up to 615.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week was published on Tuesday 4th August in the folder Astrophysics of Galaxies with the title “Small-scale turbulence alongside large-scale turbulence in a z=1.87 star-forming galaxy with an outflowing wind, revealed by multi-point structure functions” by Itzhak Goldman (Afeka College, Israel). A previous study by the author found evidence of large and small scale turbulence in the star-forming galaxy CSWA13, suggesting that star clusters and large clumps within the galaxy could be driving this turbulence.

The overlay for this paper is here

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117036181269903989

The second paper for this week, published on Thursday 6th August in the folder Astrophysics of Galaxies, is “From Clumps to Sheets: Geometry Controls the Temperature PDF of Multi-Phase Gas” by Zirui Chen and S. Peng Oh (UC Santa Barbara, USA). This study uses 3D hydrodynamic simulations to show that the temperature probability distribution functions (PDFs) of multi-phase turbulent gas differ significantly under interstellar medium (ISM) and circumgalactic medium (CGM) conditions.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047322340826393

The third paper of the week, published on Thursday 6th August in folder Instrumentation and Methods for Astrophysics is “First Detection of Extensive Air Showers Using a Small-Aperture Fluorescence Telescope” by M. Zotov (M.V. Lomonosov Moscow State University, Russia) and 7 others based in Russia and Armenia. The study reports the first-ever detection of extensive air showers from ultra-high-energy cosmic rays using a compact fluorescence telescope, employing both conventional and deep learning analysis methods.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047408583672745

The fourth and final paper of the week was published on Friday 7th August in the folder Cosmology and Nongalactic Astrophysics: “TDCOSMO XXVI: Uniform Lens Modeling of Eight Doubly Imaged Quasars“, by Ryan Brady (Stony Brook University, USA) and 9 others based all around the world, presents a new method for analyzing doubly imaged quasars using the Hubble Space Telescope, revealing that arc surface brightness is key to precision in mass model measurements.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117053056092162466

That’s all for this week. We have about a dozen more papers accepted and waiting for the authors to put the final version on arXiv, which they will presumably do when they’re back from holiday. I’ll do an update next weekend and we’ll see!

Weekly Update from the Open Journal of Astrophysics 08/08/2026

Although it’s holiday season for some, it’s time once more for another Saturday update of activity at the Open Journal of Astrophysics. Since the last update we have published a further four papers, bringing the number in Volume 9 (2026) to 167 and the total so far published by OJAp up to 615.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week was published on Tuesday 4th August in the folder Astrophysics of Galaxies with the title “Small-scale turbulence alongside large-scale turbulence in a z=1.87 star-forming galaxy with an outflowing wind, revealed by multi-point structure functions” by Itzhak Goldman (Afeka College, Israel). A previous study by the author found evidence of large and small scale turbulence in the star-forming galaxy CSWA13, suggesting that star clusters and large clumps within the galaxy could be driving this turbulence.

The overlay for this paper is here

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117036181269903989

The second paper for this week, published on Thursday 6th August in the folder Astrophysics of Galaxies, is “From Clumps to Sheets: Geometry Controls the Temperature PDF of Multi-Phase Gas” by Zirui Chen and S. Peng Oh (UC Santa Barbara, USA). This study uses 3D hydrodynamic simulations to show that the temperature probability distribution functions (PDFs) of multi-phase turbulent gas differ significantly under interstellar medium (ISM) and circumgalactic medium (CGM) conditions.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047322340826393

The third paper of the week, published on Thursday 6th August in folder Instrumentation and Methods for Astrophysics is “First Detection of Extensive Air Showers Using a Small-Aperture Fluorescence Telescope” by M. Zotov (M.V. Lomonosov Moscow State University, Russia) and 7 others based in Russia and Armenia. The study reports the first-ever detection of extensive air showers from ultra-high-energy cosmic rays using a compact fluorescence telescope, employing both conventional and deep learning analysis methods.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047408583672745

The fourth and final paper of the week was published on Friday 7th August in the folder Cosmology and Nongalactic Astrophysics: “TDCOSMO XXVI: Uniform Lens Modeling of Eight Doubly Imaged Quasars“, by Ryan Brady (Stony Brook University, USA) and 9 others based all around the world, presents a new method for analyzing doubly imaged quasars using the Hubble Space Telescope, revealing that arc surface brightness is key to precision in mass model measurements.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117053056092162466

That’s all for this week. We have about a dozen more papers accepted and waiting for the authors to put the final version on arXiv, which they will presumably do when they’re back from holiday. I’ll do an update next weekend and we’ll see!

Weekly Update from the Open Journal of Astrophysics 08/08/2026

Although it’s holiday season for some, it’s time once more for another Saturday update of activity at the Open Journal of Astrophysics. Since the last update we have published a further four papers, bringing the number in Volume 9 (2026) to 167 and the total so far published by OJAp up to 615.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week was published on Tuesday 4th August in the folder Astrophysics of Galaxies with the title “Small-scale turbulence alongside large-scale turbulence in a z=1.87 star-forming galaxy with an outflowing wind, revealed by multi-point structure functions” by Itzhak Goldman (Afeka College, Israel). A previous study by the author found evidence of large and small scale turbulence in the star-forming galaxy CSWA13, suggesting that star clusters and large clumps within the galaxy could be driving this turbulence.

The overlay for this paper is here

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117036181269903989

The second paper for this week, published on Thursday 6th August in the folder Astrophysics of Galaxies, is “From Clumps to Sheets: Geometry Controls the Temperature PDF of Multi-Phase Gas” by Zirui Chen and S. Peng Oh (UC Santa Barbara, USA). This study uses 3D hydrodynamic simulations to show that the temperature probability distribution functions (PDFs) of multi-phase turbulent gas differ significantly under interstellar medium (ISM) and circumgalactic medium (CGM) conditions.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047322340826393

The third paper of the week, published on Thursday 6th August in folder Instrumentation and Methods for Astrophysics is “First Detection of Extensive Air Showers Using a Small-Aperture Fluorescence Telescope” by M. Zotov (M.V. Lomonosov Moscow State University, Russia) and 7 others based in Russia and Armenia. The study reports the first-ever detection of extensive air showers from ultra-high-energy cosmic rays using a compact fluorescence telescope, employing both conventional and deep learning analysis methods.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117047408583672745

The fourth and final paper of the week was published on Friday 7th August in the folder Cosmology and Nongalactic Astrophysics: “TDCOSMO XXVI: Uniform Lens Modeling of Eight Doubly Imaged Quasars“, by Ryan Brady (Stony Brook University, USA) and 9 others based all around the world, presents a new method for analyzing doubly imaged quasars using the Hubble Space Telescope, revealing that arc surface brightness is key to precision in mass model measurements.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117053056092162466

That’s all for this week. We have about a dozen more papers accepted and waiting for the authors to put the final version on arXiv, which they will presumably do when they’re back from holiday. I’ll do an update next weekend and we’ll see!

“Sidewall Symphony”

Flow visualization is both an art and science in fluid dynamics. Here, researchers were interested in studying the separation bubble that forms over a backward-facing ramp–a shape that shows up, for example, on an aircraft. In these areas, the flow over the surface separates, leaving an unsteady, recirculating bubble.

That’s the flow that researchers are visualizing here. They’ve done so by adding tiny helium-filled soap bubbles to the flow. With bright lights illuminating the bubbles, each one leaves a streak in a photograph, showing where the bubble moved during the time the camera’s shutter was open. Although images like these are beautiful, they can also be analyzed by computers to extract the underlying flow that created the image. (Image and research credit: B. Steinfurth et al.; see also here)

Jupiter in a Lab

The vivid bands of a gas giant like Jupiter come from the planet’s combination of rotation and convection. It’s possible to create the same effect in a lab by rapidly spinning a tank of water around a central ice core. That’s the physical set-up behind this research poster–note the illustration in the lower right corner. The central snapshots show how temperature gradients on the water surface change the faster the tank rotates. At higher rotational speeds, the parabolic water surface gets ever steeper and Jupiter-like temperature bands form. (Image credit: C. David et al.)

ExaWind Simulation

Large-scale computational fluid dynamics simulations face many challenges. Among them is the need to capture both large physical scales–like those of Earth’s atmospheric boundary layer–and small scales–like those of tiny eddies moving around a wind-turbine blade. Capturing all of these scales for a problem like four wind turbines in a wind farm requires using the full computing power of every processor in a large supercomputer. That’s the level of power behind the simulation visualized in this video. The results, however, are stunning. (Video and image credit: M. da Frahan et al.)

Smoke Bomb

With a flurry of motion along its pectoral fin, a sting ray lifts the sand nearby and disappears into the turbid cloud. This tactic helps the animal both hide and escape. In a similar move, sting rays and other bottom-dwelling fish can bury themselves in sand.(Image credit: Y. Coll/OPOTY; via Colossal)

#fluidDynamics #fluidsAsArt #physics #science #sedimentTransport #sedimentation #stingray #turbulence

Bow Shock Instability

There are few flows more violent than planetary re-entry. Crossing a shock wave is always violent; it forces a sudden jump in density, temperature, and pressure. But at re-entry speeds this shock wave is so strong the density can jump by a factor of 13 or more, and the temperature increase is high enough that it literally rips air molecules apart into plasma.

Here, researchers show a numerical simulation of flow around a space capsule moving at Mach 28. The transition through the capsule’s bow shock is so violent that within a few milliseconds, all of the flow behind the shock wave is turbulent. Because turbulence is so good at mixing, this carries hot plasma closer to the capsule’s surface, causing the high temperatures visible in reds and yellows in the image. Also shown — in shades of gray — is the vorticity magnitude of flow around the capsule. (Image credit: A. Álvarez and A. Lozano-Duran)

#2024gofm #CFD #computationalFluidDynamics #flowVisualization #fluidDynamics #hypersonic #instability #numericalSimulation #physics #science #shockWave #turbulence

Simulating a Sneeze

Sneezing and coughing can spread pathogens both through large droplets and through tiny, airborne aerosols. Understanding how the nasal cavity shapes the aerosol cloud a sneeze produces is critical to understanding and predicting how viruses could spread. Toward that end, researchers built a “sneeze simulator” based on the upper respiratory system’s geometry. With their simulator, the team mimicked violent exhalations both with the nostrils open and closed — to see how that changed the shape of the aerosol cloud produced.

The researchers found that closed nostrils produced a cloud that moved away along a 18 degree downward tilt, whereas an open-nostril cloud followed a 30-degree downward slope. That means having the nostrils open reduces the horizontal spread of a cloud while increasing its vertical spread. Depending on the background flow that will affect which parts of a cloud get spread to people nearby. (Image and research credit: N. Catalán et al.; via Physics World)

#aerosols #biology #coughing #COVID19 #diseaseTransmission #droplets #flowVisualization #fluidDynamics #physics #science #sneezing #turbulence

Salt Affects Particle Spreading

Microplastics are proliferating in our oceans (and everywhere else). This video takes a look at how salt and salinity gradients could affect the way plastics move. The researchers begin with a liquid bath sandwiched between a bed of magnets and electrodes. Using Lorentz forcing, they create an essentially 2D flow field that is ordered or chaotic, depending on the magnets’ configuration. Although it’s driven very differently, the flow field resembles the way the upper layer of the ocean moves and mixes.

The researchers then introduce colloids (particles that act as an analog for microplastics) and a bit of salt. Depending on the salinity gradient in the bath, the colloids can be attracted to one another or repelled. As the team shows, the resulting spread of colloids depends strongly on these salinity conditions, suggesting that microplastics, too, could see stronger dispersion or trapping depending on salinity changes. (Video and image credit: M. Alipour et al.)

#2024gofm #electrohydrodynamics #flowVisualization #fluidDynamics #geophysics #magneticField #physics #plasticPollution #science #turbulence

An Article in the Annual Review of Condensed Matter Physics on Turbulence by KR Sreenivasan and J Schumacher
https://www.annualreviews.org/content/journals/10.1146/annurev-conmatphys-031620-095842

What is the turbulence problem, and when can we say it’s solved? 🌪️ This deep dive by Sreenivasan & Schumacher explores the math, physics, and engineering challenges of turbulence—from Navier-Stokes equations to intermittency and beyond. A must-read for anyone fascinated by chaos, complexity, and the unsolved mysteries of fluid dynamics! 🌀

A summary of the talk presented by KR Sreenivasan in December 2023 at the International Center for Theoretical Sciences (ICTS-TIFR) in Bengaluru, as part of a program on field theory and turbulence.
https://www.youtube.com/watch?v=fwVSBYh-KC4

"Field Theory and Turbulence" program link: https://www.icts.res.in/discussion-meeting/ftt

#FluidDynamics #Physics #NavierStokes #UnsolvedMystery #Mechanics #Dynamics #FluidMechanics #Science #Chaos #TurbulentMotion #Randomness #Chaotic #Fluid #ClassicalMechanics
#Turbulence

Kolmogorov Turbulence

Turbulent flows are ubiquitous, but they’re also mindbogglingly complex: ever-changing in both time and space across length scales both large and small. To try to unravel this complexity, scientists use simplified model problems. One such simplification is Kolmogorov flow: an imaginary flow where the fluid is forced back and forth sinusoidally. This large-scale forcing puts energy into the flow that cascades down to smaller length scales through the turbulent energy cascade. Here, researchers depict a numerical simulation of a turbulent Kolmogorov flow. The colors represent the flow’s vorticity field. Notice how your eye can pick out both tiny eddies and larger clusters in the flow; those patterns reflect the multi-scale nature of turbulence. (Image credit: C. Amores and M. Graham)

#2024gofm #flowVisualization #fluidDynamics #Kolmogorov #numericalSimulation #physics #science #turbulence #turbulentEnergyCascade

Visualizing Unstable Flames

Inside a combustion chamber, temperature fluctuations can cause sound waves that also disrupt the flow, in turn. This is called a thermoacoustic instability. In this video, researchers explore this process by watching how flames move down a tube. The flame fronts begin in an even curve that flattens out and then develops waves like those on a vibrating pool. Those waves grow bigger and bigger until the flame goes completely turbulent. Visually, it’s mesmerizing. Mathematically, it’s a lovely example of parametric resonance, where the flame’s instability is fed by system’s natural harmonics. (Video and image credit: J. Delfin et al.; research credit: J. Delfin et al. 1, 2)

#2024gofm #combustion #combustionInstability #flame #flowVisualization #fluidDynamics #instability #parametricResonance #physics #resonance #science #thermoacousticInstability #turbulence

There are videos of someone being "thrown into an overhead bin" -- official statement was "only minor injuries" but apparently at least one person had a skull fracture 😱 #turbulence #AirEuropa #aviation https://www.cnnbrasil.com.br/nacional/video-homem-sai-de-bagageiro-de-mao-apos-turbulencia-em-voo-da-air-europa/

As an #introduction - I’m an #oceanographer that literally follows the dots! I design, build and deploy #imaging systems that measure #marine #particles and use them as tracers to visualise #turbulence. It’s fun to apply these techniques to other things too - like tracking foraging #seabirds in flight. Teach #dataanalysis #optics and #autonomoussystems. Enjoy #tech #datavis #climbing #mountains #kitesurfing and #cats