Laminar Flow
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- เผยแพร่เมื่อ 9 ก.พ. 2025
- Interesting video showing Laminar Flow and demonstrating fluid flowing in layers. Very cool! Filmed at the University of New Mexico - Physics Department. This apparatus was developed by John DeMoss and Kevin Cahill of the Department of Physics & Astronomy. Interested in having your own demo unit? Please see: www.flintbox.co...
The cylinder is filled with high viscosity glycerol. Piped in are droplets of corn syrup (different viscosity) colored with food dye. Stir too quickly and they will mix; it's called turbulent flow. But, stir slowly, laminar flow, and the layers remain separate; like cards shuffled through a deck. Since the layers never truly mixed, they can be carefully separated back into their original states. Interesting physics; complex math.
cpanati same thing with toothpaste. Ever noticed how you always get nice layers? It's because of you squeeze slow enough, the layers remain separate. But if you hit it with a sledgehammer, it'll mix.
Actually, you are completely wrong. The reason why the colors return back to the original position is that, by using a thick liquid like corn syrup, as well as the cylinder that is designed to spin, exactly, the same way forward and backward, it lowers the number of random movements into the system, entropy. Since you can control any movement either way, as well as eliminate any random movement in the liquid, you are able to, essentially, undo any mixture within. The colored drops are, without question, mixed, it's just easy to unmix due to low entropy.
SMART🤓
Re = (UD)/v !!
In other words, (fluid velocity * inner diameter) / kinematic viscosity.
It's always complex maths
This is not a fake. I think it is amazing and it shows an extreme amount of creativity and intelligence to even come up with this. No more criticisms from people who obviously don't know enough about the subject.
at first I was like, meh. Kinda cool.
And then it reversed
Haven't seen my jaw since
Mysteroo Movies lol
Legend has it his jaw has never been the same again.
Some say, judging by his profile picture, that he might've never had a jaw, but a forehead instead.
Dude same😂
Yes
This is a classic of Fluid Mechanics courses (I did it) and is called the "Taylor-couette experiment" .
Because the fluids involved are thick and movement is slow, the flow stays laminar and not turbulent : there is no mixing. If one day you tried to mix 2 think paint colors, you know things are not easy to do without a though mixing !
The video should have shown what happens if we move the cylinders far more faster.
He rotated 7 times instead of 5, but apart of that, that sh*t is amazing.
this video was uploaded 16 years ago. amazing
That''s really cool... and they're really bad at counting rotations.
indeed they are. was the funny part of this vid.
+PublicEnquiry
???
@PublicEnquiry lol what
should it bother me as much as it does that they miscounted
bothers the crap out of me too. I started reading comments just to see if anyone else felt the need to point that out. 6.5 turns...
But it's understandable when you get up into such high numbers you lose your place, plus he had to concentrate on speaking into the microphone that was on the other side of the room.
I just watched the entire video and completely amazed by this laminar flow.
my favorite saying is that wonder is the seed of science, and when my kids and their friends and my grandbabies saw this, it just hit me like a ton of bricks. thank you for the enlightenment from this grateful grandma.
Within this system the entropy is already at maximum at start... the red, green, blue, and the liquid are all in equilibrium. When he spins, the flow is laminar, and therefore time-reversible. An involution function exists. Although some heat is generated due to friction (highly viscous). This causes a temp gradient, more order -> entropy decrease. And that's why the liquids did not exactly return to the state they were in, but slightly different.
Correct my if i'm wrong ;)
I believe the flow also needs to be incompressible, such that you are at a Stokes Regime (Re
That's the most enlightening potato-cam video I have seen all day.
this is oddly comforting
@Mr. M.O.G.O.M. Go get a girlfriend you loner
@Mr. M.O.G.O.M. Yeah, you, loner.
@Mr. M.O.G.O.M. Yes I do know who Paul Stamets is. Why?
They weren't mixed in the first place, that's the trick of laminar flow. The colors flow parallel to each other instead of mixing randomly like you'd see in water or air because corn syrup is a high-viscosity fluid.
With low Reynolds number (Re < 1) those kinds of processes are reversible because the flow remains laminar (as opposed to turbulent). As long as the process is not turbulent, substances in the medium will not mix.
thank you, I couldn’t hear the term he used at the point where he mentions this.
I don't get why people would think this is fake...it's supposed to demonstrate laminar flow.
"The apparatus, called a "Couette Cell," was developed by John DeMoss and Dr. Kevin Cahill, and uses dyed corn syrup to demonstrate how a fluid with a sufficiently low Reynolds number will flow along distinct paths in parallel layers (like fanning a deck of cards), thereby preventing disruption of the fluid." - Robert T. Gonzalez (from io9)
Actually, the link in the description tells you everything.
we watch this when we are stoned!!!!! meester van stroming & warmteleer bedankt!!!!!!
My mind is absolutely blown. By the way, he turns it 6.5 times, but miscounted on the initial mix up. That's why it takes 6.5 turns back to equalize.
came from reddit il5 section.. I really can't believe it! awesomeness of science.
Reddit too...way of "What is happening to the air movement inside a tire as it begins to turn, as it is turning, and after it stops?"
www.reddit.com/r/askscience/comments/13muro/what_is_happening_to_the_air_movement_inside_a/
That is amazing! I teach part of this and I will be using this video, if you do not mind! For those who understand fluid dynamics, this is a great visual.
Still teaching?
I am amazed that there is no one (at least not on page one - haven't checked the others) shouting "FAKE".
There may yet be hope for youtube...
Nice demonstration, we are building one at our university now.
I've been looking for this video for a long time!
You can also watch the hand on the right. While it's rotating forward, her finger is up, but while it's rotating backward, she puts it down.
How can people dislike this awesome video!
RIP dislikes.
The reason why the colors return back to the original position is that, by using a thick liquid like corn syrup, as well as the cylinder that is designed to spin, exactly, the same way forward and backward, it lowers the number of random movements into the system, entropy. Since you can control any movement either way, as well as eliminate any random movement in the liquid, you are able to, essentially, undo any mixture within. The colored drops are, without question, mixed, it's just easy to unmix due to low entropy.
Seriously, guys, they DID NOT reverse the video! If you compare the beginning and end of the process, the end has the cornstarch in a slightly messed up position and is slightly spread out. Look and see?
This video does kinda suggest laminar flow occurs at Re < 1 which is untrue it's Re< 2000 (well there's a transition area too )
But THIS mostly occurs at the very very low laminar flow rates
The Reynolds number, R, is the dimensionless combination:
R=ρνR/η
in which ρ is the density, ν the speed of fluid, R the size of the flow, and η the viscosity.
fluid with low Reynolds number will perform such laminar flow.
encryption / decryption
I'd say compression as some of the original data was lost but its still viewable
The wizardry here is immense. I was blind before watching this video. It was so powerful that it was the first, and the last, thing I ever saw.
Now I'm dead.
Basically, the just applied the exact same force in the opposite direction. Imagine you have a ball and shove it along a flat surface. When it comes to rest, you shove it back to where it came from, with the same force. Should end up where it started, yeah? Same principle in effect here. Usually it doesn't work because stirring things fast causes turbulent flow, which mixes things unpredictably, but if you stir thick liquids slowly like this, everything stays nice and smooth (and reversible)
Yes. Flow with low Reynolds number, also called laminar flow.
Ha... I just finished reading David Bohm's Wholeness and the Implicate Order a few weeks ago and this is one of the many analogies he gives in his book. Awesome to see it in action.
The change in entropy was there. It was the fact the the restored blobs were not exactly the same as the original.
The philosophical interpretation of this phenomena leads us to think about how something can leave its original form but still " be there" and then return. It's a clear example of how subjective or empiric science can be and that , perhaps , instruments are the only limit to knowledge.
the physical interpretation has been said: laminar parallel flow in viscous medium.
@quantumcahill That's because the system was never really disordered, just "stretched".
@Athasish Its a highly viscous fluid, most likely a form of Glycol
Barış Özcan'dan gelenler ?
Ahmet Alper Peki nasıll???
streetartglobe dan geldim
biri bana mi seslendi?
Benim düşüncem mantığım şöyle ; O katmanlar aynı yerde değil ayrı sıvı odacıklarında bu yüzden birbirlerine hiç karışmıyorlar aslında. Ama biz sadece tek yönden baktığımız için bunu göremiyoruz. Üstten baksan olayı çok net göreceğiz diye düşünüyorum.
Ümit Fatih CEBECİ biri yorumda açıklamış hızlı döndürürnce karışır ama yavaş döndürüyorlar özellikle böylece geri sarabiliyorlar ama tam nasıl plduğunu anlamadım
Are the added blobs at different distances from the center? It looks as though they're actually overlapping, but maybe that's forced perspective.
Thanks for your wonderfully insightful comment there, kathrynsuz.
Each time I've seen this, maybe 6 over a year or so, it always takes my breath away. Now I share these wonders with my grandkids, because wonder is the seed of science, and i love to smile about stuff that just knocks me out but leaves my one marble intact. spacequeen2009
Yo! That's amazing! While I was watching this, and he went backwards, I thought, "wouldn't it be cool if it were to go back to its original form in 3 dots? But that would be impossible. "
Impossible it is Not! This is super neat.
@kenny8331 yeah i thought so. Watching how slowly he rotates this thing comes to mind a significant aspect of reversable processes; they are at all times in thermodynamical equillibrium and in order for that to happen the process must be done comparatively slowly
The trick is in a chosen view angle. If you look from the top you'll see how this magic works. Layers of liquid are not mixed, they are just moving and deforming.
iPod shuffle is not random. The 'random' setting is based on an algorithm, therefore, predestined by cause and effect... so there.
@HUNNAI9095
You can use any liquid with a high viscosity. I did it with corn syrup and it worked really well
this is aaabsolutely amazing, i like this an extreme amount.
what was the clear substance in the glass? i assumed water at first but after it looked as if it had some vicosity. i would really like to know as i am a physics student and i have to give a presentation on soemthing bad ass. i want to do this but i need to know what the clear stuff is !! and i have never seen something this crazy woooo! awesome video soo cool,!!
I don't have a problem with computer scientists. And i most certainly do appreciate the work that goes into it.
@Athasish I don't think its either, too clear to be corn syrup i would think, and the corn syrup die he injected wouldn't just hang there like that if it was water. It is probably something close to the consistency of corn syrup though..
yeah, they look to be spaced away from each other radially. each individual color stretches, but i dont think they overlap.
God forbid I don't know the next color coming. Love the video.
nice demostration
My prof should show this be4 fluid mechanics lecture about laminar and turbulent. I was blind before this video and read comments. This is amazing btw. Even some human error showed.
They've blinded me...with science! Pretty cool stuff.
nice and specific there, is it my touch typing technique that bothers you?
yes This is true
if you want to belief see the left hand in the beginning of video bothe hands at the seam time but in the end of video the left hand move away firest and the second thing the shape of the ink is a different in the end and beginning of video.
i have completed an undergraduate degree in physics, taken undergraduate maths modules and have many friends who studied engineering, i am well aware of the corresponding course content of these degrees.
Only a physics major can master Einstein's theory of relativity but cannot count backwards from five.
@michealrofail I don't know if you noticed, but you didn't use a single full stop in your comment, so I have no idea what you were trying to say.
Laminar flow is a proven physical phenomenon...
@TKflyer You mean, 6.5 turns, right? Looks like the guy in the video isn't the only one who can't count.
Very impressive experiment.
This may be a demonstration about behavior of high viscosity liquid, isn't it ?
I think this clip is not a Fake.
Though I'm not a specialist...
It appears that it wasn't reversed - there was a hand on the left at the beginning, which moved shortly after the first turn, but it doesn't appear at the end again.
I sometimes contemplate applying thermodynamics to the 4 systems. Heat the caldron up at bit. Heat the 🔴 a bit more. Plop the 🟢in. Cool the 🔵 a bit. Run the system a bit and take some notes
No, it actually doesn't. Entropy can be overcome by adding energy to the system. What your asking is equivalent of asking if making your bed in the morning violates entropy. Does that make since?
They should have posted another video that is taped from above (or below)...
ARGHH THIS HAS BLOWN MY MIND!
It's called "liquid memory" and occurs in liquids of low reynolds number and high viscosity
I think this is not something reversible,fluid layers flow indipendently and dyes don't diffuse into neighbouring layers.Think of this flow as people starting in rows entering a curve and speeding the curve with the same angular velocity,as the hands of a clock,observing them from outside they seem a disordered crowd,but looking them from upside they are disposed as curved rows,so that when you revert the motion,they return in place.
Blurring of drops at the end is due to non constant speed.
cool. i learn this in school and don't know wth is laminar flow. this helps!
Damn science, you always make my brain confuse
Is that transparent liquid the water or the syrup?
Thank you
UNM Physics and Astronomy, very cool!
If more college students had this same realization before enrolling, the world would be a better place.
amazing, i wonder if that would work with water if u moved real real slow...
You stirred forward and backward 6 times sir. You didnt count two until you were on three, but all the same it is a cool concept to see in action.
Thank you ''Barış Özcan'' channel!
Holy shit, physics is cool. I can't handle the high level math, but I love watching the experiments and demonstrations of fluids with weird properties.
You just blew my mind.
WHAAAAT wow. i love these little demonstration videos.
Science, you are awesome!
Actually, yes, I was required to take 2 Chemistry classes for my degree in Physics. I also had to take Calc 1, 2, & 3 and Differential Equations. Does that mean i am a failed mathematician?
thanks for posting this. very cool.
Their is a local band in my city that has a song called laminar flow. i had to come check this out.
yo what container u stired them n
plss i ned as soon as possible
Oh man, this is freakin' cool and awesome.
They're definitely at different radii. That is the "trick" to avoid the colours blending.
Wow. this is amazing!
It would be sweet if we had a handle that can reverse entropy like this as well.
i dont know if you noticed but it looks very fake look at the left hand when he starts moving it moves again at last of the video an the guy stirring at first he puts his other hand on the table witch is erased at the end of the video with a brighter tone than that of the table you can also note that the movement of the colours is the same but in backwards
saw this on a show called Richard Hammond's Engineering Connections.
You are right, totally forgot momentum. Then it's both momentum and a heat gradient which causes the time-irriversibility part...
The entropy is at minimum from an information point of view? Because the different colors have exactly the same properties right? Equally dense, temperature etc.(Except for color) No reason for it to to mix...?
I got to read more about entropy ;)
nice use of a comma there to end your comment, unconventional - i like it. I have actually never read a textbook, i don't need to study outside of lectures. I am also known for my charisma and good people skills within a field that is not reknowned for this quality, hence my success with presentations on subject matters.
If you watch the right hand of the woman on the right, you'll see that her pinky is bent while he turns the crank, and she straightens it after the first backwards count. It looks pretty real to me.
try and picture the coloured liquids as rubber, or another elastic solid, and then you might understand how it works a little better.
dude that is really cool can you give a supply list so i could do this in school
That is so COOL!
@paulme33 it's not, low reynolds numbers flow is time reversible
Is that a hand-crank time machine
because that's what it seems like
What is the clear base solution made of?
the base solution is corn syrup. the dyes are color dyes mixed with a little bit of corn syrup for consistency.