Hacker News new | ask | show | jobs
by aaren 4614 days ago
a 'Rankine vortex' is a fancy name for a very simple theoretical model.

It's just a circular vortex in which u~1/r and there may or may not be a solid body core. A lot of spinny vortices are like this.

I'm not sure where they think their rankine vortex is - whether in the bottle or round the outside - or whether they are accounting for friction when calling it that.