English: Darwin drift due to the passage of a rigid sphere, according to potential flow theory. The dark blue line is a timeline: a line of fluid parcels followed in time and deformed by the passage of the sphere. The timeline passes through the symmetry axis of the flow. The orange dots are drifters to indicate the path that fluid parcels follow when the sphere passes. A cross section through the Darwin drift volume is shown in light yellow. Several streamlines – as observed in a frame of reference moving with the sphere – are drawn in gray.
== {{int:filedesc}} == {{Information |Description={{en|1=Darwin drift due to the passage of a rigid sphere, according to potential flow theory. The dark blue line is a [[:en:Streamlines, streaklines, and path...