marangoni effect

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Many solids can dissolve in liquids like water, and while this is often treated as a matter of chemistry, fluid dynamics can play a role as well. As seen in this video by Beauty of Science, the dissolving candy coating of an M&M spreads outward from the candy. This is likely surface-tension-driven; as the coating dissolves, it changes the surface tension near the candy and flow starts moving away thanks to the Marangoni effect. With multiple candies dissolving near one another, these outward flows interfere and create more complex flow patterns. 

These flows directly affect the dissolving process by altering flow near the candy surface, which may increase the rate of dissolution by scouring away loose coating. They can also change the concentration of dissolved coating in different areas, which then feeds back to the flow by changing the surface tension gradient. (Video and image credit: Beauty of Science)

anonymous asked:

Hey, we were set a homework to take an original photo which has something to do with physics. Do you have some idea what photo could I take?

Well, these are some things which we have covered in FYP ( and in my other blogs ) during yester times and hope this helps with your homework. Cheers!


Polymer Balls


Oobleck - An amusing Non Newtonian Fluid


The Double Slit Experiment ( Veritasium )


Center of Mass


The Marangoni Effect powered Boat


DIY: Smart phone into a Holographic Projector


Total Internal Reflection


Refraction


There is soo much more cool physics stuff happening out there. This list is just the tip of iceberg.

Just look around and you ought to find physics lurking in almost everything and everywhere.

Have fun exploring and bedazzle your teacher with your thoughts kid! Good Day!

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ARTISTIC SURFACE TENSION

Chemical Bouillon are a trio of artists who use the chemistry of surface reactions to create abstract videos full of exploding and imploding droplets and colors. As chemicals react, local concentrations at the interface vary, which changes the local surface tension. These gradients drive flow from areas of low surface tension to those of higher surface tension. This is called the Marangoni effect - the same behavior that drives tears in a glass of wine. Chemical Bouillon have a whole YouTube channel dedicated to these kinds of videos, with everything from inks to ferrofluids.  Shout out to fuckyeahfluiddynamics for this one!

Ink drops atop a layer of glycerol spread in a beautiful fan of blue and white. The ink’s motion is the result of two processes: molecular diffusion and the Marangoni effect. Molecular diffusion is the mixing that occurs due to the random background motion of molecules. Since glycerol is a very viscous liquid, the ink is quite slow to spread in this manner. 

The second factor, the Marangoni effect, is driven by differences in surface tension. The ink and glycerol have different surface tensions, and the exact values depend on concentration. Notice how the ink drops spread fastest from areas where the ink is densely concentrated. This tells us that the ink’s surface tension is lower than the glycerol’s. As a result, the glycerol’s higher surface tension tends to pull ink toward it. As the ink spreads and its concentration decreases relative to the glycerol, the ink-glycerol mixture’s surface tension increases. Since the difference between the surface tension of the mixture and the pure glycerol is not as large, the Marangoni force is reduced and the spreading slows. (Image credit: C. Kalelkar, source)

As fragile as a soap bubble seems, these films have remarkable powers of self-healing. The animation above shows a falling water droplet passing through a soap film without bursting it. An important factor here is that the water droplet is wet–passing a dry object through a soap film is a quick way to burst it, as those who have played with bubbles know. The droplet’s inertia deforms the soap film, creating a cavity. If the drop’s momentum were smaller, the film could actually bounce the droplet back like a trampoline, but here the droplet wins out. The film breaks enough to let the drop through, but its cavity quickly pinches off and the film heals thanks to the stabilizing effect of its soapy surfactants. (Image credit: H. Kim, source)

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The brilliant colors of a soap film reveal the fluid’s thickness, thanks to a process known as thin film interference. The twisting flow of the film depends on many influences: gravity pulls down on the liquid and tends to make it drain away; evaporation steals fluid from the film; local air currents can push or pull the film; and the variation in the concentration of molecules – specifically the surfactants that stabilize the film – will change the local surface tension, causing flow via the Marangoni effect. Together these and other effects create the dancing turbulence captured above. (Video credit: A. Filipowicz)

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The seemingly-alive dancing droplets are back in a new video from Veritasium. These droplets of food coloring attract, merge, and chase one another due to evaporation and surface tension interactions between their two components: water and propylene glycol. Because the droplets are constantly evaporating, they are surrounded by a cloud of vapor that helps determine a drop’s surface tension. These localized differences in surface tension are what causes the drops to attract. The chasing is also surface-tension-driven. Like any liquid, the drops will flow from areas of low surface tension to those of higher surface tension due to the Marangoni effect. Thus drops of different concentration appear to chase one another. This is a relatively simple experiment to try yourself at home, and Derek outlines what you need to know for it.  (Video credit: Veritasium; research credit: N. Cira et al.; submitted by @g_durey)

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This fantastic music video by Kim Pimmel is a beautiful merger of art and fluid dynamics. Using household goods (and some slightly more exotic ferrofluid), the video shows how mesmerizing diffusion, buoyancy, Marangoni flow, and other fluid effects can be up close. It may also be the first time I’ve ever seen fluid dynamics–specifically bubbles–used as characters! Also be sure to check out some of his previous videos, many of which also feature cool fluid dynamics. (Video credit and submission: K. Pimmel)

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It’s only fitting to take a moment to look back at 2014 as we step into the New Year. It was a big year in many respects - we hit 1000 posts and broke 200,000 followers; I started producing FYFD videos on our YouTube channel; and, on a personal note, I finished up my PhD. But since we’re all about the science around here, I will give you, without further ado, the top 10 FYFD posts of 2014:

1. Bioluminescent crustaceans use light for defense
2. What happens when you step on lava
3. Flapping flight deconstructed
4. Wingtip vortices demonstrated
5. Saturn’s auroras
6. Raindrops’ impact on sand
7. Water spheres in microgravity
8. The surreal undulatus asperatus cloud
9. Inside a plunging breaker
10. A simply DIY Marangoni effect demo

I can’t help but notice that 9 out of the 10 posts feature animated GIFs. Oh, Tumblr, you rascals. Happy New Year! (Image credits: BBC; A. Rivest; E. Lutz; Nat. Geo/BBC2; ESA/Hubble; R. Zhao et al.; D. Petit; A. Schueth; B. Kueny and J. Florence; Flow Visualization at UC Boulder)

The very best of FYP - 2015

2015 was a very special year for FYP.

The blog started out as any other a few months back, merely as a place to share a few interesting thoughts between two friends.

But it is now a medium for us to share the ecstasies that abstract the world and break deadlocks that might taunt us from within.

Here are the top FYP posts for the year 2015:

Gravity pwned - Acoustic Levitation

Where did the stars go?

Corona Discharge.

This is what happens when Two Black Holes Collide.

The fabric of Space and Time

Behold, Physics!

Meet Oobleck ( Corn Starch )- A Non- Newtonian Fluid!

Complex numbers are NOT complex!

Roller Coaster Physics.

Supermoon Lunar Eclipse

The Marangoni Effect - An affair with Surface Tension.

Perceiving Light at Trillion Frames per second !!

A big thank you to all the followers of the blog for your support and encouragement, for without wings a bird could never fly and likewise, we would have been dormant had it not been for a followers like you who insisted that we make it BIG.. Thanks a lot guys!


With Love,

fuckyeahphysica.

Watch on fuckyeahfluiddynamics.tumblr.com

Have a little science enthusiasm from Bill Nye to brighten your Tuesday! This video includes demonstrations on thermodynamics (sucking the balloon into the flask), the Marangoni effect (driving the powder off the water surface and powering the glue boat by creating gradients in surface tension), and buoyancy (floating cans of cola).