Turbulent Flow is MORE Awesome Than Laminar Flow

Everyone loves laminar flow but turbulent flow is the real MVP.

Special thanks to:

I got into turbulent flow via chaos. The transition to turbulence sometimes involves a period doubling. Turbulence itself is chaotic motion, it is unpredictable and sensitively dependent on initial conditions. What surprised me is all the ways turbulent flow is useful to us. It is diffusive, meaning it causes mixing. This is useful in jet engines or rocket nozzles (which Destin studies) and is important to achieve in microfluidic devices, which are so small that turbulent flow is actually difficult to achieve. Turbulent flow can energize a boundary layer, which is important to maintain flow attachment over a wing, maintaining lift and delaying stall. Similarly a turbulent boundary layer over a golf ball reduces pressure drag allowing golf balls to fly further. This is the reason for the dimples on golf balls. Flow transitioning to turbulence in the wake of a bluff body can create periodic vortex shedding. This beautiful phenomenon can be seen in the von Kàrmàn vortex street in clouds viewed from space. Turbulence is everywhere, in the air currents in a room, in your aorta, in the breaths you exhale, in oil pipelines and water pipes, in the flow over cars and ships and planes. Animals have evolved for it (like dead fish swimming up stream) and we have engineered our environment, our planes and golf balls for it. Laminar flow may be nice to look at (which is why we use it in decorative fountains) but turbulent flow does the real lifting.

Animations by:
Jonny Hyman (Sun, Jupiter, Reynolds, airfoil, Earth time-lapse)

Research and writing:
AJ Fillo and Derek Muller. AJ also created the wind tunnel golf ball shots

Filmed by:
Daniel Bydlowski and Derek Muller

Additional footage:
Images of Jupiter courtesy of NASA

Music:

[smartereveryday]

LAMINAR FLOW IS BETTER. Obviously the Laminar Boundary Layer section was the best part of the video. (I jest.) In all seriousness though I thought you did an amazing job with this content Derek. Discussing the transition to turbulence is very difficult and you did a masterful job of it here. Animating Reynold’s experiment on the page was masterful. Your point that laminar flow must be small was very interesting, and when I saw the images from space I had a fun time thinking about what parts were laminar and what parts were turbulent. I’ll put a link to this video on the laminar flow video. All these nice things being said....I have something up my sleeve!

[lfk]

The first thing i thought when i saw this title is "You just started a war with Destin".😀😀😀

[AthAthanasius]

I was NOT surprised to see Destin at the start of this as my first thought when I saw the title of this video in the notification email was "uh-oh, shots fired, Destin's not going to stand for this".

[FlynChse]

Took a class just called “Turbulence” during my aerospace M.S. and I understood just as much about turbulent flow at the end of the course as at the beginning.

[AMOGHAJAYANTHMK]

Here before Veritasium Vs Smarter Everyday diss tracks.

[Bakhrod]

Friendship ended with Laminar flow, now turbulent flow is my best Friend

[devinochs]

As a plumber, this is fantastic. I've tried explaining these concepts to people and it is hard for them to grasp without visual representations of what the concepts are. In plumbing, turbulence is the enemy. Everyone thinks more is better and IT IS NOT.

[deltacanadien-francais]

I’m pretty sure this is the closest thing to a disstrack we’ll see from these guys

[GODOFMAYHEM]

Engineer throws dead fish in the water.
Engineer: "Behold, Necromancy!"

[numbers]

turbulent flow: *exists*

fish swimming upstream: cHaOs Is A lAdDeR

[danchisholm]

I love the play that you and destin have. you guys are becoming cornerstones of science and yet your friendship makes it so friendly and kind.

[starship]

As an aerospace engineer I'm so glad this video was made. I love Destin's video on laminar flow but I kept thinking "but but but the flow is so much easier to separate if the flow is laminar"
But also, you can't just mention that a dead fish can swim upstream in a sentence and move on! That deserves it's own video! How does something move upstream without it expending energy! How does an object move forwards when you blow on it! The only explanation I have is there is lower pressure closer to where the vortex is shed than far downstream, so the fish is being "blown" upstream by the pressure difference...

[ceejec]

"laminar flow is slow, superficial. It's a toy. That's why its most notable use is on decorative fountains"

Most scientific diss track on YouTube

[flyprdu]

I had a meteorology professor that had a saying when talking about the atmosphere:
"Big swirls, have smaller swirls, which feed on their velocity.
Smaller swirls have lesser swirls, and so on to viscosity."

[billdoolinofficial]

I didnt knew the term of it. But always loved the turbulence flow. Started loving it when i paint and wash my brush my in the water. Colors mixed in water in a beautiful way.

[JM-usfr]

As soon as I saw the title, I was like, "Oh man, he's picking a fight with Destin. This is gonna be good"

[EdwardChan.]

15:13
Fish: *dies*
Turbulent Flow: Dead or Alive, you're coming with me

[lucas]

Derek: Turbulence is amazing
Destin: So you have chosen death

[isaacteal]

This is the one of the best science/info vids I have seen on YouTube. I’m a weather forecaster and this does such a great job helping visualize what is going on in 3d space

[shybrain]

As an aerospace engineering student, this was a love letter