Make Your Own Pythagorean Cup
divisbyzero.com
divisbyzero.com
It's not printed yet, but apart from the excessive overhang at the top of the handle I think it will work.
Side view at 50% opacity: https://img.jes.xxx/2003
I’d go more for a toilet flush type of thing if I redid it.
It finished printing and works as it should, but it takes an extremely long time to drain.
tobr suggested an alternative design elsewhere in this thread: https://i.postimg.cc/FR7Qc9M5/0845194-D-F5-DE-46-D6-8200-CB9... - I think it would be easier to conceal a larger tube within that, so I might have to try that too.
And a 50% opacity view: https://img.jes.xxx/2005
The first cup took 90 seconds to drain about 200ml. The cross-sectional area of the tube in the second version is about 4.7x larger, so if my beginner-level understanding of Bernoulli's principle is accurate, I expect it to drain about 4.7x faster, so maybe it'll empty itself in 20 seconds instead of 90.
The average flow rate is 12.5 ml/sec vs 2.2 ml/sec before, so it's 5.6x better!
The cup is wider at the top than the bottom, which means when you tilt it over you are removing some liquid from a narrow part of the cup and adding an equal volume of liquid to a wide part of the cup. That means the level drops slightly.
1: Excuse the crappy drawing, https://i.postimg.cc/FR7Qc9M5/0845194-D-F5-DE-46-D6-8200-CB9...
> "The pipe acts as a siphon much as the plumbing does in a modern toilet."
Two phase flow is a difficult subject, so much so the owner of a nuclear engineering consultancy I worked for wrote his magnum opus on it: Two-Phase Flow in Complex Systems It's imperative to get right in process environments like chemical production facilities and nuclear reactors. https://www.wiley.com/WileyCDA/WileyTitle/productCd-04713296...
In my washing machine (LG) rinsing slot...
I know, because I always have to be very careful not to overfill it. But usually there is some leftower water in its pipe so it does not keep the fluid even if I not overfill - so nowadays I routinely take it apart and shake it dry before each washing - clever but not to convenient...