#2024gofm — Public Fediverse posts

Entraining Bubbles

Every time I fill a glass at my refrigerator, I watch how the falling jet creates a cloud of bubbles. The bubbles form when the impacting water jet pulls air in with it, though, as this video shows, the exact origins can vary. Here, researchers take a closer, slowed-down look at the situation; they connect disturbances in the jet and waves at its base to the entrained bubbles that form. (Video and image credit: S. Relph and K. Kiger)

#2024gofm #bubbles #entrainment #flowVisualization #fluidDynamics #jets #physics #science

Entraining Bubbles

Every time I fill a glass at my refrigerator, I watch how the falling jet creates a cloud of bubbles. The bubbles form when the impacting water jet pulls air in with it, though, as this video shows, the exact origins can vary. Here, researchers take a closer, slowed-down look at the situation; they connect disturbances in the jet and waves at its base to the entrained bubbles that form. (Video and image credit: S. Relph and K. Kiger)

#2024gofm #bubbles #entrainment #flowVisualization #fluidDynamics #jets #physics #science

Entraining Bubbles

Every time I fill a glass at my refrigerator, I watch how the falling jet creates a cloud of bubbles. The bubbles form when the impacting water jet pulls air in with it, though, as this video shows, the exact origins can vary. Here, researchers take a closer, slowed-down look at the situation; they connect disturbances in the jet and waves at its base to the entrained bubbles that form. (Video and image credit: S. Relph and K. Kiger)

#2024gofm #bubbles #entrainment #flowVisualization #fluidDynamics #jets #physics #science

Entraining Bubbles

Every time I fill a glass at my refrigerator, I watch how the falling jet creates a cloud of bubbles. The bubbles form when the impacting water jet pulls air in with it, though, as this video shows, the exact origins can vary. Here, researchers take a closer, slowed-down look at the situation; they connect disturbances in the jet and waves at its base to the entrained bubbles that form. (Video and image credit: S. Relph and K. Kiger)

#2024gofm #bubbles #entrainment #flowVisualization #fluidDynamics #jets #physics #science

Crown Splash

When a falling drop hits a thin layer of water, the impact sends up a thin, crown-shaped splash. This research poster shows a numerical simulation of such a splash in the throes of various instabilities. The crown’s thick edges are undergoing a Rayleigh-Plateau instability, breaking into droplets much the way a dripping faucet does. On the far side, the crown has rapidly expanding holes that pull back and collide. The still-intact liquid sheet at the base of the crown shows some waviness, as well, hinting at a growing instability there. (Image credit: L. Kahouadji et al.)

#2024gofm #CFD #computationFluidDynamics #crownSplash #fluidDynamics #instability #physics #PlateauRayleighInstability #science #splashing

Crown Splash

When a falling drop hits a thin layer of water, the impact sends up a thin, crown-shaped splash. This research poster shows a numerical simulation of such a splash in the throes of various instabilities. The crown’s thick edges are undergoing a Rayleigh-Plateau instability, breaking into droplets much the way a dripping faucet does. On the far side, the crown has rapidly expanding holes that pull back and collide. The still-intact liquid sheet at the base of the crown shows some waviness, as well, hinting at a growing instability there. (Image credit: L. Kahouadji et al.)

#2024gofm #CFD #computationFluidDynamics #crownSplash #fluidDynamics #instability #physics #PlateauRayleighInstability #science #splashing

Crown Splash

When a falling drop hits a thin layer of water, the impact sends up a thin, crown-shaped splash. This research poster shows a numerical simulation of such a splash in the throes of various instabilities. The crown’s thick edges are undergoing a Rayleigh-Plateau instability, breaking into droplets much the way a dripping faucet does. On the far side, the crown has rapidly expanding holes that pull back and collide. The still-intact liquid sheet at the base of the crown shows some waviness, as well, hinting at a growing instability there. (Image credit: L. Kahouadji et al.)

#2024gofm #CFD #computationFluidDynamics #crownSplash #fluidDynamics #instability #physics #PlateauRayleighInstability #science #splashing

Crown Splash

When a falling drop hits a thin layer of water, the impact sends up a thin, crown-shaped splash. This research poster shows a numerical simulation of such a splash in the throes of various instabilities. The crown’s thick edges are undergoing a Rayleigh-Plateau instability, breaking into droplets much the way a dripping faucet does. On the far side, the crown has rapidly expanding holes that pull back and collide. The still-intact liquid sheet at the base of the crown shows some waviness, as well, hinting at a growing instability there. (Image credit: L. Kahouadji et al.)

#2024gofm #CFD #computationFluidDynamics #crownSplash #fluidDynamics #instability #physics #PlateauRayleighInstability #science #splashing

Dancing Metal Droplets

Droplets of a gallium alloy are liquid at room temperature. When spiked with aluminum grains and immersed in a solution of NaOH, the droplets change shape and move in a random fashion. This video delves into the phenomenon, describing how a chemical reaction with the aluminum grains changes the local surface tension and creates Marangoni flows that make the droplets move. To get the droplet motion, you need to have the aluminum concentration just right. With too little, there’s not enough Marangoni flow. With too much, the hydrogen gas produced in the chemical reaction disrupts the droplet motion. (Video and image credit: N. Kim)

https://www.youtube.com/watch?v=XYRj0Ty9udo

#2024gofm #chemistry #droplets #fluidDynamics #marangoniEffect #physics #science #surfaceTension

Dancing Metal Droplets

Droplets of a gallium alloy are liquid at room temperature. When spiked with aluminum grains and immersed in a solution of NaOH, the droplets change shape and move in a random fashion. This video delves into the phenomenon, describing how a chemical reaction with the aluminum grains changes the local surface tension and creates Marangoni flows that make the droplets move. To get the droplet motion, you need to have the aluminum concentration just right. With too little, there’s not enough Marangoni flow. With too much, the hydrogen gas produced in the chemical reaction disrupts the droplet motion. (Video and image credit: N. Kim)

https://www.youtube.com/watch?v=XYRj0Ty9udo

#2024gofm #chemistry #droplets #fluidDynamics #marangoniEffect #physics #science #surfaceTension

Dancing Metal Droplets

Droplets of a gallium alloy are liquid at room temperature. When spiked with aluminum grains and immersed in a solution of NaOH, the droplets change shape and move in a random fashion. This video delves into the phenomenon, describing how a chemical reaction with the aluminum grains changes the local surface tension and creates Marangoni flows that make the droplets move. To get the droplet motion, you need to have the aluminum concentration just right. With too little, there’s not enough Marangoni flow. With too much, the hydrogen gas produced in the chemical reaction disrupts the droplet motion. (Video and image credit: N. Kim)

https://www.youtube.com/watch?v=XYRj0Ty9udo

#2024gofm #chemistry #droplets #fluidDynamics #marangoniEffect #physics #science #surfaceTension

Dancing Metal Droplets

Droplets of a gallium alloy are liquid at room temperature. When spiked with aluminum grains and immersed in a solution of NaOH, the droplets change shape and move in a random fashion. This video delves into the phenomenon, describing how a chemical reaction with the aluminum grains changes the local surface tension and creates Marangoni flows that make the droplets move. To get the droplet motion, you need to have the aluminum concentration just right. With too little, there’s not enough Marangoni flow. With too much, the hydrogen gas produced in the chemical reaction disrupts the droplet motion. (Video and image credit: N. Kim)

https://www.youtube.com/watch?v=XYRj0Ty9udo

#2024gofm #chemistry #droplets #fluidDynamics #marangoniEffect #physics #science #surfaceTension

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

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

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

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

“Droplet on a Plucked Wire”

What happens to a droplet hanging on a wire when the wire gets plucked? That’s the fundamental question behind this video, which shows the effects of wire speed, viscosity, and viscoelasticity on a drop’s detachment. With lovely high-speed video and close-up views, you get to appreciate even subtle differences between each drop. Capillary waves, viscoelastic waves, and Plateau-Rayleigh instabilities abound! (Video and image credit: D. Maity et al.)

#2024gofm #droplets #fluidDynamics #physics #science #viscoelasticity #viscousFlow

“Droplet on a Plucked Wire”

What happens to a droplet hanging on a wire when the wire gets plucked? That’s the fundamental question behind this video, which shows the effects of wire speed, viscosity, and viscoelasticity on a drop’s detachment. With lovely high-speed video and close-up views, you get to appreciate even subtle differences between each drop. Capillary waves, viscoelastic waves, and Plateau-Rayleigh instabilities abound! (Video and image credit: D. Maity et al.)

#2024gofm #droplets #fluidDynamics #physics #science #viscoelasticity #viscousFlow

“Droplet on a Plucked Wire”

What happens to a droplet hanging on a wire when the wire gets plucked? That’s the fundamental question behind this video, which shows the effects of wire speed, viscosity, and viscoelasticity on a drop’s detachment. With lovely high-speed video and close-up views, you get to appreciate even subtle differences between each drop. Capillary waves, viscoelastic waves, and Plateau-Rayleigh instabilities abound! (Video and image credit: D. Maity et al.)

#2024gofm #droplets #fluidDynamics #physics #science #viscoelasticity #viscousFlow

“Droplet on a Plucked Wire”

What happens to a droplet hanging on a wire when the wire gets plucked? That’s the fundamental question behind this video, which shows the effects of wire speed, viscosity, and viscoelasticity on a drop’s detachment. With lovely high-speed video and close-up views, you get to appreciate even subtle differences between each drop. Capillary waves, viscoelastic waves, and Plateau-Rayleigh instabilities abound! (Video and image credit: D. Maity et al.)

#2024gofm #droplets #fluidDynamics #physics #science #viscoelasticity #viscousFlow

Manu Jumping, a.k.a. How to Make a Big Splash

The Māori people of Aotearoa New Zealand compete in manu jumping to create the biggest splash. Here’s a fun example. In this video, researchers break down the physics of the move and how it creates an enormous splash. There are two main components — the V-shaped tuck and the underwater motion. At impact, jumpers use a relatively tight V-shape; the researchers found that a 45-degree angle works well at high impact speeds. This initiates the jumper’s cavity. Then, as they descend, the jumper unfolds, using their upper body to tear open a larger underwater cavity, which increases the size of the rebounding jet that forms the splash. To really maximize the splash, jumpers can aim to have their cavity pinch-off (or close) as deep underwater as possible. (Video and image credit: P. Rohilla et al.)

#2024gofm #diving #flowVisualization #fluidDynamics #manuJumping #physics #science #splashes #sports #WorthingtonJet

Manu Jumping, a.k.a. How to Make a Big Splash

The Māori people of Aotearoa New Zealand compete in manu jumping to create the biggest splash. Here’s a fun example. In this video, researchers break down the physics of the move and how it creates an enormous splash. There are two main components — the V-shaped tuck and the underwater motion. At impact, jumpers use a relatively tight V-shape; the researchers found that a 45-degree angle works well at high impact speeds. This initiates the jumper’s cavity. Then, as they descend, the jumper unfolds, using their upper body to tear open a larger underwater cavity, which increases the size of the rebounding jet that forms the splash. To really maximize the splash, jumpers can aim to have their cavity pinch-off (or close) as deep underwater as possible. (Video and image credit: P. Rohilla et al.)

#2024gofm #diving #flowVisualization #fluidDynamics #manuJumping #physics #science #splashes #sports #WorthingtonJet

Manu Jumping, a.k.a. How to Make a Big Splash

The Māori people of Aotearoa New Zealand compete in manu jumping to create the biggest splash. Here’s a fun example. In this video, researchers break down the physics of the move and how it creates an enormous splash. There are two main components — the V-shaped tuck and the underwater motion. At impact, jumpers use a relatively tight V-shape; the researchers found that a 45-degree angle works well at high impact speeds. This initiates the jumper’s cavity. Then, as they descend, the jumper unfolds, using their upper body to tear open a larger underwater cavity, which increases the size of the rebounding jet that forms the splash. To really maximize the splash, jumpers can aim to have their cavity pinch-off (or close) as deep underwater as possible. (Video and image credit: P. Rohilla et al.)

#2024gofm #diving #flowVisualization #fluidDynamics #manuJumping #physics #science #splashes #sports #WorthingtonJet

Manu Jumping, a.k.a. How to Make a Big Splash

The Māori people of Aotearoa New Zealand compete in manu jumping to create the biggest splash. Here’s a fun example. In this video, researchers break down the physics of the move and how it creates an enormous splash. There are two main components — the V-shaped tuck and the underwater motion. At impact, jumpers use a relatively tight V-shape; the researchers found that a 45-degree angle works well at high impact speeds. This initiates the jumper’s cavity. Then, as they descend, the jumper unfolds, using their upper body to tear open a larger underwater cavity, which increases the size of the rebounding jet that forms the splash. To really maximize the splash, jumpers can aim to have their cavity pinch-off (or close) as deep underwater as possible. (Video and image credit: P. Rohilla et al.)

#2024gofm #diving #flowVisualization #fluidDynamics #manuJumping #physics #science #splashes #sports #WorthingtonJet

Bigger Particles Slide Farther

Mudslides and avalanches typically carry debris of many shapes and sizes. To understand how debris size affects flows like these, researchers use simplified, laboratory-scale experiments like this one. Here, researchers mix a slurry of silicone oil and glass particles of roughly two sizes. The red particles are larger; the blue ones smaller. Sitting in a cup, the mixture tends to separate, with red particles sinking faster to form the bottom layer and smaller blue particles collecting on top. And what happens when such a mixture flows down an incline? The smaller blue particles tend to settle out sooner, leaving the larger red particles in suspension as they flow downstream. (Video and image credit: S. Burnett et al.)

#2024gofm #flowVisualization #fluidDynamics #gravityCurrent #particleSuspension #physics #science #suspension #viscousFlow

Bigger Particles Slide Farther

Mudslides and avalanches typically carry debris of many shapes and sizes. To understand how debris size affects flows like these, researchers use simplified, laboratory-scale experiments like this one. Here, researchers mix a slurry of silicone oil and glass particles of roughly two sizes. The red particles are larger; the blue ones smaller. Sitting in a cup, the mixture tends to separate, with red particles sinking faster to form the bottom layer and smaller blue particles collecting on top. And what happens when such a mixture flows down an incline? The smaller blue particles tend to settle out sooner, leaving the larger red particles in suspension as they flow downstream. (Video and image credit: S. Burnett et al.)

#2024gofm #flowVisualization #fluidDynamics #gravityCurrent #particleSuspension #physics #science #suspension #viscousFlow

Bigger Particles Slide Farther

Mudslides and avalanches typically carry debris of many shapes and sizes. To understand how debris size affects flows like these, researchers use simplified, laboratory-scale experiments like this one. Here, researchers mix a slurry of silicone oil and glass particles of roughly two sizes. The red particles are larger; the blue ones smaller. Sitting in a cup, the mixture tends to separate, with red particles sinking faster to form the bottom layer and smaller blue particles collecting on top. And what happens when such a mixture flows down an incline? The smaller blue particles tend to settle out sooner, leaving the larger red particles in suspension as they flow downstream. (Video and image credit: S. Burnett et al.)

#2024gofm #flowVisualization #fluidDynamics #gravityCurrent #particleSuspension #physics #science #suspension #viscousFlow

Bigger Particles Slide Farther

Mudslides and avalanches typically carry debris of many shapes and sizes. To understand how debris size affects flows like these, researchers use simplified, laboratory-scale experiments like this one. Here, researchers mix a slurry of silicone oil and glass particles of roughly two sizes. The red particles are larger; the blue ones smaller. Sitting in a cup, the mixture tends to separate, with red particles sinking faster to form the bottom layer and smaller blue particles collecting on top. And what happens when such a mixture flows down an incline? The smaller blue particles tend to settle out sooner, leaving the larger red particles in suspension as they flow downstream. (Video and image credit: S. Burnett et al.)

#2024gofm #flowVisualization #fluidDynamics #gravityCurrent #particleSuspension #physics #science #suspension #viscousFlow

Kirigami in the Flow

Kirigami is a paper art that combines folding and cutting to create elaborate shapes. Here, researchers use cuts in thin sheets of plastic and explore how the sheets transform in a flow. Depending on the configuration of cuts, the sheets can stretch dramatically in the flow, creating complex, dynamic, and beautiful wakes. I feel like there must be some applications out there that would benefit from kirigami-induced mixing. (Video and image credit: A. Carleton and Y. Modarres-Sadeghi)

#2024gofm #flowVisualization #fluidDynamics #kirigami #mathematics #physics #science

Kirigami in the Flow

Kirigami is a paper art that combines folding and cutting to create elaborate shapes. Here, researchers use cuts in thin sheets of plastic and explore how the sheets transform in a flow. Depending on the configuration of cuts, the sheets can stretch dramatically in the flow, creating complex, dynamic, and beautiful wakes. I feel like there must be some applications out there that would benefit from kirigami-induced mixing. (Video and image credit: A. Carleton and Y. Modarres-Sadeghi)

#2024gofm #flowVisualization #fluidDynamics #kirigami #mathematics #physics #science

Kirigami in the Flow

Kirigami is a paper art that combines folding and cutting to create elaborate shapes. Here, researchers use cuts in thin sheets of plastic and explore how the sheets transform in a flow. Depending on the configuration of cuts, the sheets can stretch dramatically in the flow, creating complex, dynamic, and beautiful wakes. I feel like there must be some applications out there that would benefit from kirigami-induced mixing. (Video and image credit: A. Carleton and Y. Modarres-Sadeghi)

#2024gofm #flowVisualization #fluidDynamics #kirigami #mathematics #physics #science

Kirigami in the Flow

Kirigami is a paper art that combines folding and cutting to create elaborate shapes. Here, researchers use cuts in thin sheets of plastic and explore how the sheets transform in a flow. Depending on the configuration of cuts, the sheets can stretch dramatically in the flow, creating complex, dynamic, and beautiful wakes. I feel like there must be some applications out there that would benefit from kirigami-induced mixing. (Video and image credit: A. Carleton and Y. Modarres-Sadeghi)

#2024gofm #flowVisualization #fluidDynamics #kirigami #mathematics #physics #science

Drops on the Edge

Drops impacting a dry hydrophilic surface flatten into a film. Drops that impact a wet film throw up a crown-shaped splash. But what happens when a drop hits the edge of a wet surface? That’s the situation explored in this video, where blue-dyed drops interact with a red-dyed film. From every angle, the impact is complex — sending up partial crown splashes, generating capillary waves that shift the contact line, and chaotically mixing the drop and film’s liquids. (Video and image credit: A. Sauret et al.)

#2024gofm #crownSplash #dropletImpact #droplets #flowVisualization #fluidDynamics #fluidsAsArt #physics #science #wetting

Drops on the Edge

Drops impacting a dry hydrophilic surface flatten into a film. Drops that impact a wet film throw up a crown-shaped splash. But what happens when a drop hits the edge of a wet surface? That’s the situation explored in this video, where blue-dyed drops interact with a red-dyed film. From every angle, the impact is complex — sending up partial crown splashes, generating capillary waves that shift the contact line, and chaotically mixing the drop and film’s liquids. (Video and image credit: A. Sauret et al.)

#2024gofm #crownSplash #dropletImpact #droplets #flowVisualization #fluidDynamics #fluidsAsArt #physics #science #wetting

Drops on the Edge

Drops impacting a dry hydrophilic surface flatten into a film. Drops that impact a wet film throw up a crown-shaped splash. But what happens when a drop hits the edge of a wet surface? That’s the situation explored in this video, where blue-dyed drops interact with a red-dyed film. From every angle, the impact is complex — sending up partial crown splashes, generating capillary waves that shift the contact line, and chaotically mixing the drop and film’s liquids. (Video and image credit: A. Sauret et al.)

#2024gofm #crownSplash #dropletImpact #droplets #flowVisualization #fluidDynamics #fluidsAsArt #physics #science #wetting

Drops on the Edge

Drops impacting a dry hydrophilic surface flatten into a film. Drops that impact a wet film throw up a crown-shaped splash. But what happens when a drop hits the edge of a wet surface? That’s the situation explored in this video, where blue-dyed drops interact with a red-dyed film. From every angle, the impact is complex — sending up partial crown splashes, generating capillary waves that shift the contact line, and chaotically mixing the drop and film’s liquids. (Video and image credit: A. Sauret et al.)

#2024gofm #crownSplash #dropletImpact #droplets #flowVisualization #fluidDynamics #fluidsAsArt #physics #science #wetting

Salt Fingers

Any time a fluid under gravity has areas of differing density, it convects. We’re used to thinking of this in terms of temperature — “hot air rises” — but temperature isn’t the only source of convection. Differences in concentration — like salinity in water — cause convection, too. This video shows a special, more complex case: what happens when there are two sources of density gradient, each of which diffuses at a different rate.

The classic example of this occurs in the ocean, where colder fresher water meets warmer, saltier water (and vice versa). Cold water tends to sink. So does saltier water. But since temperature and salinity move at different speeds, their competing convection takes on a shape that resembles dancing, finger-like plumes as seen here. (Video and image credit: M. Mohaghar et al.)

#2024gofm #convection #doubleDiffusiveConvection #doubleDiffusiveInstability #flowVisualization #fluidDynamics #oceanography #physics #science

Salt Fingers

Any time a fluid under gravity has areas of differing density, it convects. We’re used to thinking of this in terms of temperature — “hot air rises” — but temperature isn’t the only source of convection. Differences in concentration — like salinity in water — cause convection, too. This video shows a special, more complex case: what happens when there are two sources of density gradient, each of which diffuses at a different rate.

The classic example of this occurs in the ocean, where colder fresher water meets warmer, saltier water (and vice versa). Cold water tends to sink. So does saltier water. But since temperature and salinity move at different speeds, their competing convection takes on a shape that resembles dancing, finger-like plumes as seen here. (Video and image credit: M. Mohaghar et al.)

#2024gofm #convection #doubleDiffusiveConvection #doubleDiffusiveInstability #flowVisualization #fluidDynamics #oceanography #physics #science

Salt Fingers

Any time a fluid under gravity has areas of differing density, it convects. We’re used to thinking of this in terms of temperature — “hot air rises” — but temperature isn’t the only source of convection. Differences in concentration — like salinity in water — cause convection, too. This video shows a special, more complex case: what happens when there are two sources of density gradient, each of which diffuses at a different rate.

The classic example of this occurs in the ocean, where colder fresher water meets warmer, saltier water (and vice versa). Cold water tends to sink. So does saltier water. But since temperature and salinity move at different speeds, their competing convection takes on a shape that resembles dancing, finger-like plumes as seen here. (Video and image credit: M. Mohaghar et al.)

#2024gofm #convection #doubleDiffusiveConvection #doubleDiffusiveInstability #flowVisualization #fluidDynamics #oceanography #physics #science

Salt Fingers

Any time a fluid under gravity has areas of differing density, it convects. We’re used to thinking of this in terms of temperature — “hot air rises” — but temperature isn’t the only source of convection. Differences in concentration — like salinity in water — cause convection, too. This video shows a special, more complex case: what happens when there are two sources of density gradient, each of which diffuses at a different rate.

The classic example of this occurs in the ocean, where colder fresher water meets warmer, saltier water (and vice versa). Cold water tends to sink. So does saltier water. But since temperature and salinity move at different speeds, their competing convection takes on a shape that resembles dancing, finger-like plumes as seen here. (Video and image credit: M. Mohaghar et al.)

#2024gofm #convection #doubleDiffusiveConvection #doubleDiffusiveInstability #flowVisualization #fluidDynamics #oceanography #physics #science

Twisting in the Flow

What happens to liquid crystals in a flow? In this video, researchers look at liquid crystals flowing through the narrow gap of a microfluidic device. Initially, all the crystals are oriented the same way, as if they are logs rolling down a river. But as the flow rate increases, narrow lines appear in the flow, followed by disordered regions, and, eventually, a new configuration: vertical bands streaking the left-to-right flow. The colors, in this case, indicate the orientation of the liquid crystals. As the researchers show, the crystals collectively twist to form the spontaneous bands. (Video and image credit: D. Jia and I. Bischofberger)

#2024gofm #flowVisualization #fluidDynamics #instability #liquidCrystals #physics #science

Twisting in the Flow

What happens to liquid crystals in a flow? In this video, researchers look at liquid crystals flowing through the narrow gap of a microfluidic device. Initially, all the crystals are oriented the same way, as if they are logs rolling down a river. But as the flow rate increases, narrow lines appear in the flow, followed by disordered regions, and, eventually, a new configuration: vertical bands streaking the left-to-right flow. The colors, in this case, indicate the orientation of the liquid crystals. As the researchers show, the crystals collectively twist to form the spontaneous bands. (Video and image credit: D. Jia and I. Bischofberger)

#2024gofm #flowVisualization #fluidDynamics #instability #liquidCrystals #physics #science

Twisting in the Flow

What happens to liquid crystals in a flow? In this video, researchers look at liquid crystals flowing through the narrow gap of a microfluidic device. Initially, all the crystals are oriented the same way, as if they are logs rolling down a river. But as the flow rate increases, narrow lines appear in the flow, followed by disordered regions, and, eventually, a new configuration: vertical bands streaking the left-to-right flow. The colors, in this case, indicate the orientation of the liquid crystals. As the researchers show, the crystals collectively twist to form the spontaneous bands. (Video and image credit: D. Jia and I. Bischofberger)

#2024gofm #flowVisualization #fluidDynamics #instability #liquidCrystals #physics #science

Twisting in the Flow

What happens to liquid crystals in a flow? In this video, researchers look at liquid crystals flowing through the narrow gap of a microfluidic device. Initially, all the crystals are oriented the same way, as if they are logs rolling down a river. But as the flow rate increases, narrow lines appear in the flow, followed by disordered regions, and, eventually, a new configuration: vertical bands streaking the left-to-right flow. The colors, in this case, indicate the orientation of the liquid crystals. As the researchers show, the crystals collectively twist to form the spontaneous bands. (Video and image credit: D. Jia and I. Bischofberger)

#2024gofm #flowVisualization #fluidDynamics #instability #liquidCrystals #physics #science

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

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

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

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

A Drop’s Shape Effects

Falling raindrops get distorted by the air rushing past them, ultimately breaking large droplets into many smaller ones. This research poster shows how variable this process is by showing two different raindrops, both of the same 8-mm initial diameter. On the left, the drop is prolate — longer than it is wide — and on the right, the drop is oblate — wider than it is long. Moving from bottom to top, we see a series of snapshots of each drop’s shape as it deforms and, eventually, breaks into smaller drops. The overall process is similar for each: the drop flattens, dimples, and then inflates like a sail, with part of the drop thinning into a sheet and ultimately breaking into smaller droplets. Yet, each drop’s specific details are entirely different. (Image credit: S. Dighe et al.)

A Drop’s Shape Effects

Falling raindrops get distorted by the air rushing past them, ultimately breaking large droplets into many smaller ones. This research poster shows how variable this process is by showing two different raindrops, both of the same 8-mm initial diameter. On the left, the drop is prolate — longer than it is wide — and on the right, the drop is oblate — wider than it is long. Moving from bottom to top, we see a series of snapshots of each drop’s shape as it deforms and, eventually, breaks into smaller drops. The overall process is similar for each: the drop flattens, dimples, and then inflates like a sail, with part of the drop thinning into a sheet and ultimately breaking into smaller droplets. Yet, each drop’s specific details are entirely different. (Image credit: S. Dighe et al.)

A Drop’s Shape Effects

Falling raindrops get distorted by the air rushing past them, ultimately breaking large droplets into many smaller ones. This research poster shows how variable this process is by showing two different raindrops, both of the same 8-mm initial diameter. On the left, the drop is prolate — longer than it is wide — and on the right, the drop is oblate — wider than it is long. Moving from bottom to top, we see a series of snapshots of each drop’s shape as it deforms and, eventually, breaks into smaller drops. The overall process is similar for each: the drop flattens, dimples, and then inflates like a sail, with part of the drop thinning into a sheet and ultimately breaking into smaller droplets. Yet, each drop’s specific details are entirely different. (Image credit: S. Dighe et al.)

A Drop’s Shape Effects

Falling raindrops get distorted by the air rushing past them, ultimately breaking large droplets into many smaller ones. This research poster shows how variable this process is by showing two different raindrops, both of the same 8-mm initial diameter. On the left, the drop is prolate — longer than it is wide — and on the right, the drop is oblate — wider than it is long. Moving from bottom to top, we see a series of snapshots of each drop’s shape as it deforms and, eventually, breaks into smaller drops. The overall process is similar for each: the drop flattens, dimples, and then inflates like a sail, with part of the drop thinning into a sheet and ultimately breaking into smaller droplets. Yet, each drop’s specific details are entirely different. (Image credit: S. Dighe et al.)

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

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

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

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

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

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

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