# How Can We Simulate Water Droplets? 🌊 ## Метаданные - **Канал:** Two Minute Papers - **YouTube:** https://www.youtube.com/watch?v=SxIkQt04WCo - **Дата:** 18.08.2020 - **Длительность:** 5:09 - **Просмотры:** 137,287 - **Источник:** https://ekstraktznaniy.ru/video/14085 ## Описание ❤️ Check out Linode here and get $20 free credit on your account: https://www.linode.com/papers 🎬Our Instagram page with the slow-motion videos is available here: https://www.instagram.com/twominutepapers/ 📝 The paper "Codimensional Surface Tension Flow using Moving-Least-SquaresParticles" is available here: https://web.stanford.edu/~yxjin/pdf/codim.pdf https://web.stanford.edu/~yxjin/ ❤️ Watch these videos in early access on our Patreon page or join us here on YouTube: - https://www.patreon.com/TwoMinutePapers - https://www.youtube.com/channel/UCbfYPyITQ-7l4upoX8nvctg/join 🙏 We would like to thank our generous Patreon supporters who make Two Minute Papers possible: Aleksandr Mashrabov, Alex Haro, Alex Paden, Andrew Melnychuk, Angelos Evripiotis, Benji Rabhan, Bruno Mikuš, Bryan Learn, Christian Ahlin, Daniel Hasegan, Eric Haddad, Eric Martel, Gordon Child, Javier Bustamante, Lorin Atzberger, Lukas Biewald, Michael Albrecht, Nikhil Velpanur, Owen Campbell-Moore, Owen Skarpn ## Транскрипт ### [] Dear Fellow Scholars, this is Two Minute Papers with Dr. Károly Zsolnai-Fehér. A computer graphics paper from approximately 3 years ago was able to simulate the motion of these bubbles, and even these beautiful collision events between them in a matter of milliseconds. This was approximately 300 episodes ago, and in this series, we always say that two more papers down the line, and this will be improved significantly. So now, once again, here goes another one of those Two Minute Papers moments of truth. Now, three years later, let’s see how this field evolved. Let’s fire up this new technique that will now, simulate the evolution of two cube-shaped droplets for us. In reality, mother nature would make sure that the surface area of these droplets is minimized, let’s see…yes, droplets form immediately, so the simulation program understands surface tension, and the collision event is also simulated beautifully. A+. However, this was possible with previous methods, for instance, a paper by the name Surface-Only Liquids could also pull it off, so what’s new here? Well, let’s look under the hood and find out. ### Droplet collision (1/2x) [1:11] Oh yes. This is different. You see, normally, if we do this breakdown, we get triangle meshes, this is typically how these surfaces are represented. But I don’t see any meshes here, I see particles! Great, but what does this enable us to do? Look here. ### 8-sided fluid polygon [1:33] If we break down the simulation of this beautiful fluid polygon, we see that there is not only one kind of particle here! There are three kinds! With light blue, we see sheet particles, the yellow ones are filament particles, and if we look inside, with dark blue here, you see volume particles. With these building blocks, and the proposed new simulation method, we can create much more sophisticated surface tension-related phenomena! So let’s do exactly that! For instance, here, you see soap membranes stretching due to wind flows. ### Blowing bubbles (1/2x) [2:05] They get separated, lots of topological changes take place, and the algorithm handles it correctly. In an other example, this soap bubble has been initialized with a hole, and you can see it cascading through the entire surface. Beautiful work! And, after we finish the simulation of these fluid chains, we can look under the hood ### Fluid chain [2:33] and see how the algorithm thinks about this piece of fluid. ### Flyid chain (1/2x) [2:38] Once again, with dark blue, we have the particles that represent the inner volume of the water chains, and on the outside, there is a thin layer of sheet particles holding them together. What a clean and beautiful visualization. So, how much do we have to wait to get these results? A bit. Simulating this fluid chain example took roughly 60 seconds per frame. This droplet on a plane example runs approximately ten times faster than that, it needs only ### Droplet on the plane [3:04] 6. 5 seconds for each frame. This was one of the cheaper scenes in the paper, and you may be wondering, which one was the most expensive? This water bell took almost two minutes for each frame, and here, when you see this breakdown ### Watechell [3:19] from the particle color coding, you know exactly what we are looking at. Since part of this algorithm runs on your processor, and a different part on your graphics card, there is plenty of room for improvements in terms of the computation time for a followup ### Film catenoid (1/2x) [3:37] paper. I cannot wait to see these beautiful simulations in real time two more papers down the line. What a time to be alive! I also couldn’t resist creating a slow-motion version of some of these videos, if this is ### 6-sided fluid polygon [3:48] something that you wish to see, make sure to click our Instagram page link in the video description for more. Thanks for watching and for your generous support, and I'll see you next time!