Behind the Scenes: Two Vortex Rings Colliding in SLOWMO (4 yrs, 12 hour MEGACUT) Smarter Every Day

Original Video Here: https://youtu.be/EVbdbVhzcM4 High Res Images here: Please subscribe if this video earned it: http://bit.ly/Subscribe2SED Feeling Ambitious? Crossword Puzzle Here: https://docs.google.com/forms/d/e/1FAIpQLSeYX-FEO9SmbmRfytX0iTj-kv9Pyru5jqUfd71nvgdau4pjVQ/viewform ⇊ Click below for more links! ⇊ High resolution photos for Patrons here: https://www.patreon.com/posts/high-quality-19568610 We used a computer controlled cylinder to pump fluid behind a rubber membrane to fire toroidal vortices out of the vortex cannons. We fixed one of the vortex cannon in a stationary position, and used a multi-axis microscope stage to align a second cannon to it… which sounds incredibly easy, until you realize that DYE density was an experiment all on its own. If the density of the dye mix was light than water, the vortex would go up. If the dye was more dense than water the vortex would fall. We had to overcome SO MANY VARIABLES to overcome and we basically spent about 4 hours figuring each variable. Water/dye temperature differential Water turbulence Water turbidity (cloudiness or haziness of a fluid) How to reset the aquarium Cannon Spacing Cannon Nozzle Cannon Shape Dye homogeneity in the vortex itself The piston displacement volume The piston stroke speed Rubber diaphragm tension, would make one side fire faster than the other. Water or air to drive diaphram? Firing speed (too slow and they drift, too fast and turbulence tears apart secondaries) We did a complete redesign of the cannon 3 different times. The Dye loading method was changed several times At times We tried to maintain negative pressure on the cannon chamber… we also tried to put shutters on the front of the muzzle. Ultimately I decided it was ok to live with dye dripping out of the front. We had to premix the dyes and eventually we got there. It got to the point where we didn’t even really know what success looked like and always thought we were there. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ GET SMARTER SECTION A Vortex Ring is also called a Toroidal Vortex https://en.wikipedia.org/wiki/Vortex_ring Original Research Paper by T. T. Lim & T. B. Nickels (Published in Nature 1992) http://202.118.74.190/~elizabeth/Docs/34_Instability_Head-on%20collision_of_large_VR.pdf Governing Equations of Fluid Mechanics http://www.eng.auburn.edu/~tplacek/courses/fluidsreview-1.pdf Numerical Analysis of this phenomena http://fluid.itcmp.pwr.wroc.pl/~znmp/Publikacje/JP_2014_Kudela_Kosior.pdf Interesting Research Papers on Vortex Ring Reconnection https://pdfs.semanticscholar.org/3721/e67f5bf8e88a47e2241058c7e3cc064c5e8a.pdf Other Videos created by Dr. T T Lim http://me.nus.edu.sg/dept/limtt/videogallery.html Flow Visualization, A Book by Dr. T T Lim https://www.amazon.com/Flow-Visualization-Techniques-Examples-Second/dp/1848167911/ref=mt_hardcover?_encoding=UTF8&me=&qid=1529505335 Why we typically don’t talk about angular momentum in fluids. https://physics.stackexchange.com/questions/127712/why-dont-we-talk-about-angular-momentum-at-all-in-fluid-mechanics ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The thought is my efforts making videos will help educate the world as a whole, and one day generate enough revenue to pay for my kids college education. Until then if you appreciate what you've learned in this video and the effort that went in to it, please SHARE THE VIDEO! If you REALLY liked it, feel free to pitch a few dollars Smarter Every Day by becoming a Patron. http://www.patreon.com/smartereveryday Warm Regards, Destin