5. Flow Visualization

[@fahmylina123]

Very nice presentation of steady (laminar) and unsteady (turbulent) flow, indeed, that can hardly be imagined without such genius visualization of the deviation of path lines and stream lines and the formation of stalls

[@macro820]

Don't forget, the stream line is defined as any line that at a given instance is everywhere tangent to the velocity vectors in the flow field.

[@laurasegura1350]

Thank you very much for this, indeed the best series I saw so far, now everything is computer modeling and there is no comparison with the real life stuff.

[@JayLikesLasers]

The video and audio becomes increasingly out of sync.

[@MultiMind100]

video and audio are really out of sync......is somebody knows how to fix it....plz help........otherwise videos are perfect and giving clear details about fluod mechanics....good stuff ...

[@NutsKleerofski]

yeah, all the videos start being out of synch at some points, and at the end of the video the delay can be 5-6 seconds, it's really hard to watch it like that

[@carbon273]

So here is my analogy on the whole concept between path lines, streaklines and streamlines: Imagine you, with a line of people enter a building that has a lobby section and a secondary entrance that is only a turnstile door which turns either left or right arbitrarily (north or south direction). This is similar to the gate example shown around the 10 minute mark. The entrance into the lobby is considered your fixed point. For pathlines, let’s focus on you as the individual of study. You project that by the time you enter the secondary entrance or turnstile you would be going in the south direction. So tracing forward from where you are, that is considered your path line. Now consider that the line that you are on, itself is the object of study. From the first entrance, or fixed point. The number of people behind you are lined up respectively. However, you know that because of the turnstile, some of the people behind you will be going through the north direction and some, the south direction. The streakline connects or traces a line from you on the line to the person behind you and so on until traced to the person at the first entrance. So because of the turnstile, in a sense, the next 3 people in line behind you most likely will not enter through the same direction as you did. The streamline is the instantaneous speed of the line being moved. The analogy doesn’t work to well with this one but I would assume that it is just, at a fixed point in time, the speed at with all the people are moving in that line due to the turnstile obstruction. Also Keep in mind that my analogy is completely discrete whereas for fluids themselves, they are continuous, assuming the continuum hypothesis.

[@TARUNAKASH1992]

i understood it like this. Stream line is just projection of the streakline at a particular instance of time. Btw, the video is much better on the MIT website. techtv.mit.edu/collections/ifluids/videos/32598-flow-visualization.

[@felipemanfrin9948]

You can open two videos and mute one of them. Then you synchronize yourself the audio from one video with the imagem of the other.

[@SimoneHochgreb]

What is the licensing on these videos? where does the advertising revenue go to? NSF, hopefully?

[@joestanek2010]

5:49

[@michaelcaruso4582]

Wonderful I have seen some of this in my mind but this is the best yet. Thanks you for helping me continue my life long learning. Mike Caruso

[@聂品]

start to worry about my numerical simulation of the flow... turbulance and transitory status are really hard to say...

[@anirudhagarwal950]

Does anyone who is well versed in modern gas and fluid dynamics know if we have solved the unsolved question he mentions in 20:10ish where he says that we have not yet solved the question about how the transition form no stall to stall takes place

[@Annetje94]

+Anirudh Agarwal I believe, and correct me if I'm wrong, that the problem still isn't solved. I think it is the Navier-Stokes existence and smoothness problem, it's one of the seven Millenium Problems. If you can solve it, you can earn a million dollars :)

[@cocemojoe]

Thanks every one involved in producing this documentary.

[@ilovethesmellofdbranesinth7945]

where can I get hi res video?

[@mountains889]

how would you get a high res video from a video that was never recorded with that kind of detail?

[@ilovethesmellofdbranesinth7945]

The video artifacts here are pixelations, which were clearly added by poor digital video compression.

[@EarlWallaceNYC]

Thanks for uploading these videos. I found them very helpful.

[@JC-11111]

Wow! This is extremely informative and easy to understand.

[@IKarma97]

Like si estas aquí por el profesor de Dinámica de Fluidos :v

[@cocemojoe]

This was another fantastic visual I only wish they had placed a camera above to give us a 2 dimensional view for a better interpretation. I couldn't tell if the last image was a serpentine plume or a vortex plume.

[@andreas3861]

these videos are great thankyou for sharing!

[@dlwatib]

Transient, not transhent. Transhent is the pronunciation people used when I was growing up to talk about migrant farm laborers when they wanted to make it sound like the migrants were trailer trash.

[@aminhafiz89]

this is great stuff..

[@dhoomsaad4406]

دكتور فاروق

[@qr-ec8vd]

Loving this~~!!

[@RodrigoOliveira-jm5en]

Thumbs up if prodanoff sent you here!