# Simulating Honey Coiling | Two Minute Papers #158 ## Метаданные - **Канал:** Two Minute Papers - **YouTube:** https://www.youtube.com/watch?v=ZEjUqZU1hNQ - **Дата:** 31.05.2017 - **Длительность:** 3:59 - **Просмотры:** 35,255 ## Описание The paper "Variational Stokes: A Unified Pressure-Viscosity Solver for Accurate Viscous Liquids" is available here: https://cs.uwaterloo.ca/~elariono/stokes/index.html Recommended for you: Simulating Viscosity and Melting Fluids - https://www.youtube.com/watch?v=KgIrnR2O8KQ Two Minute Papers Merch: US: http://twominutepapers.com/ EU/Worldwide: https://shop.spreadshirt.net/TwoMinutePapers/ WE WOULD LIKE TO THANK OUR GENEROUS PATREON SUPPORTERS WHO MAKE TWO MINUTE PAPERS POSSIBLE: Andrew Melnychuk, Christian Lawson, Dave Rushton-Smith, Dennis Abts, e, Esa Turkulainen, Michael Albrecht, Sunil Kim, VR Wizard. https://www.patreon.com/TwoMinutePapers Music: Antarctica by Audionautix is licensed under a Creative Commons Attribution license (https://creativecommons.org/licenses/by/4.0/) Artist: http://audionautix.com/ Thumbnail background image credit: https://pixabay.com/photo-1006972/ Splash screen/thumbnail design: Felícia Fehér - http://felicia.hu Károly Zsolnai-Fehér's links: Facebook → https://www.facebook.com/TwoMinutePapers/ Twitter → https://twitter.com/karoly_zsolnai Web → https://cg.tuwien.ac.at/~zsolnai/ ## Содержание ### [0:00](https://www.youtube.com/watch?v=ZEjUqZU1hNQ) Segment 1 (00:00 - 03:00) Dear Fellow Scholars, this is Two Minute Papers with Károly Zsolnai-Fehér. This episode is about simulating a beautiful phenomenon in nature, the buckling and coiling effect of honey. Mmm! This effect is due to the high viscosity of materials like honey, which means that they are highly resistant against deformation. Water, however, is much less viscous as it is held together by weaker intermolecular forces, therefore it is easier to deform, making it so easy to pour it into a glass. We had an earlier episode on honey buckling, and as every seasoned Fellow Scholar already knows, the link is available in the video description. One key difference of this work is that the older solution was built upon a Lagrangian approach, which means that the simulation consists of computing the velocities and the pressure that acts on these particles. It is a particle-based simulation. Here, a solution is proposed for the Eulerian approach, which means that we do not compute these quantities everywhere in the continuum of space, but we use a fine 3D grid, and we compute these quantities only in these gridpoints. No particles to be seen anywhere. There are mathematical techniques to try to guess what happens between these individual gridpoints, and this process is referred to as interpolation. So normally, in this grid-based approach, if we wish to simulate such a buckling effect, we'll be sorely disappointed because what we will see is that the surface details rapidly disappear due to the inaccuracies in the simulation. The reason for this is that the classical grid-based simulators utilize a technique that mathematicians like to call operator splitting. This means that we solve these fluid equations by taking care of advection, pressure, and viscosity separately. Separate quantities, separate solutions. This is great, because it eases the computational complexity of the problem, however, we have to pay a price for it in the form of newly introduced inaccuracies. For instance, some kinetic and shear forces are significantly dampened, which leads to a loss of detail for buckling effects with traditional techniques. This paper introduces a new way of efficiently solving these operators together in a way that these coupling effects are retained in the simulation. The final solution not only looks stable, but is mathematically proven to work well for a variety of cases, and it also takes into consideration collisions with other solid objects correctly. I absolutely love this, and anyone who is in the middle of creating a new movie with some fluid action going on has to be all over this new technique. And, the paper is absolutely amazing. It contains crystal clear writing, many paragraphs are so tight that I'd find it almost impossible to cut even one word from them, yet it is still digestible and absolutely beautifully written. Make sure to have a look, as always, the link is available in the video description. These amazing papers are stories that need to be told to everyone. Not only to experts. To everyone. And before creating these videos, I always try my best to be in contact with the authors of these works. And nowadays, many of them are telling me that they were really surprised by the influx of views they got after they were showcased in the series. Writing papers that are featured in Two Minute Papers takes a ridiculous amount of hard work, and after that, the researchers make them available for everyone free of charge. And now, I am so glad to see them get more and more recognition for their hard work. Absolutely amazing. Thanks for watching and for your generous support, and I'll see you next time! --- *Источник: https://ekstraktznaniy.ru/video/14651*