Self-starting siphon - GIF

[Altair]

Self-starting siphon.




Previously:

Shake starting a siphon - GIF
U-shaped PVC siphon - GIF
Simple irrigation siphon - GIF
Shake-starting a siphon - GIF

[BuffaloJohn]

OK, that is cool!

[CharlesWaugh]

Inertia seems to do the trick.

[jzanter]

can't quite see what's going on other than it appears to be a transient condition setup in the tube geometry before immersion?

[schuylergrace]

can't quite see what's going on other than it appears to be a transient condition setup in the tube geometry before immersion?

You have to shove a self-starting siphon, like that, into the water fairly quickly, which forces water up and over the first hump. On the backside of the first hump, gravity helps the situation, too, and accelerates the water (gives it more kinetic energy) to the point where it can shoot all the way up to the top of the second hump and over. At that point, it becomes a conventional siphon. As long as the outlet is below the water level in the container you're siphoning from, it will continue to run.

You can accomplish the same thing with a conventional siphon by plugging the outlet, submerging the inlet side in the liquid you're siphoning, and releasing the plug. If you have the inlet deep enough and the hump leading to the outlet is close enough to the level of the surface of the liquid, the inrush of water will have enough force to rise above the liquid's surface and over the hump.

[that_other_guy]

Got it!
Sorcery.