Some dolphins are known to blow bubble rings themselves and play with them using their “nose” (rostrum to use the correct term), not just biting or smashing them, but directing the vortex and moving them around.
Dolphins are intelligent, curious, playful creatures.
They are also well known gang rapists…..just saying.

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The creator put some answers in the comments:

How the heck did i make it?

The living room of my father's place had a very strong ceiling fan, which could go in reverse. Instead of blowing air down, it would pull the air up. That would create an updraft strong enough to sustain the vortex. Next, I had a box fan and a blanket set up to redirect the air flow so it rotated around the center of the room. You can see it as the dark blue object in the back right. After the fans were turned on, I laid out an old dark red bed sheet with a small PVC pipe underneath it connected to a fog machine. The bed sheet allowed the fog to gently seep through and get pulled into the vortex, as opposed to being blasted out of the pipe. And then it was all a matter of letting the ceiling fan's updraft and the box fan's rotation mix into a 10 ft tall indoor tornado!!

Why didn't the wake vortex flip that drone to oblivion?

Interesting vortex at coming off the wings or tail at ~4:20

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Counter-rotating propellers sparked my curiosity when I first saw them on a British Seafire Mk46 at a flight show in the early nineties.

So my amateur's answer would be that it's about the problem of turning the engine's power into thrust. With increasing power, you can either increase the propeller's RPM or its area. So you either a) spin it faster, b) increase its diameter, c) use a more favourable blade geometry, d) add more blades.

a) and b) both lead to blade tips moving faster, and once they approach the speed of sound, wave drag sets in and ruins your day. b) also runs into issues in terms of ground clearance. Thus the Kim Jong-un blades on planes like the An-70: short and fat.

c) is rather difficult to do in terms of manufacture -- that's why more pronounced blade shapes are a relatively recent development.

d) on a single propeller decreases the efficiency of each blade as it passes through the previous blade's vortex. That's why, for instance, German planes in WW2 almost exclusively relied on 3-bladed propellers with increasing blade size, whereas Supermarine went to four and even 5 blades rather quickly. You can work the issue to a certain degree by modifying the blade geometry, thus the 8 blade props on a modern A400M.

Adding more blades by adding another propeller gets around d), although the aft prop still loses efficiency compared to the front prop. On the other hand, counter-rotating props massively reduces problems with torque, which can be rather horrendous for single engine prop planes. The Bf 109, for instance, is (in)famous for being difficult during take-off as it pulls to the side quite violently.

*promote the semantic vortex

The two key words there are "vortex" and "spin". A nerf vortex WILL spin, whereas these guys almost certainly designed this NOT to spin (probably at the cost of aerodynamic efficiency).

I am seriously tempted.

My only worry would be losing the damn thing in the trees!

Great idea, but you can buy a nerf vortex for $10, hollow it out, and put your gopro in it.
These guys have obviously practiced their throws to be able to keep it pointed in the right direction and not spin. They did far better than I thought they would.
*quality low tech advancement in high tech photography

I drove right under the core of this thing going home. I could actually see a tornado being made and I checked all the weather and News outlets and there was nothing, except that NOAA decided to throw a Severe Thunderstorm Warning 10 minutes up AFTER IT PASSED...

It was so crazy to see a tornadic supercell in West Valley City (Salty Lake City, for most Sifters). It was following 2700 West for a bit and then I-215 (nearing the airport) was moving super fast to the NNE, straight to Washington Terrace and Riverdale. The winds were wild and the cloud formations were awesome, they were moving fast enough that I thought a partial nub might be visible where I was at, but I never did see it.

All that I saw was the main vortex with the amazing sight of all the cold air being sucked into the vortex at the SSW corner of the leading edge. Which was twisting more than fast enough to be a "horizontal twister". It was rotating so fast it was amazing; since you could see that sight you knew all it needed was a bit of air to push against it from underneath and stand up some of those vortices around the central core and then, walla, you'd get the tornado (I actually did believe that Ogden or Bountiful would get one since that was where it was heading).

All it needed was to get a little closer to the mountains and you'd have the right ingredients.

Thus, this is what you see happen right here in this video. North of my house, out in the middle of the Great Salt Lake, sits Antelope Island. It got hit by the raining part of this tornadic system but look at this wonderful storm video from it:

https://twitter.com/AntelopeSP/status/779078436568518656

It even had some golf ball hail in it.

The uploader said this on yt one year ago: "People, I shot this video on a beach in Costa Rica, I did NOT make this trap. I just saw a bunch of kids around it and shot the video. Please don't blame ME for the hermit crabs being trapped forever in this swirling vortex of hell.. thank you."

What I'd like to know is how these Costa Rican children created an eternal swirling vortex of hell...

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God dammit, pressure is not how wings produce lift! (in his defence it's an extremely common mis-explanation)

If it was then they wouldn't ever work upside down (which they clearly can do when designed for it). Nor does the top and bottom airflow always meet again on the other side evenly, or in fact is the bottom stream always faster than the top.

Bernoulli's principle augments lift in efficient designs, but it's newtons 3rd law which actually makes them work.

You can even see the wash vortex falling down off the wings flying through smoke. It's the equal and opposite reaction from this deflection that causes the majority of lift and drag from a wing .