Smooth, laminar, honey-like flow of espresso out of a bottomless portafilter. The viscous flow starts wide and is rapidly pulled inwards into one unified stream as it accelerates. This picture was taken near the end of a shot, so the stream has turned from a deep brown into a blonde stream.

Report can be found here: https://www.flowvis.org/wp-content/uploads/2026/09/Flow_Vis___Get_Wet-6.pdf