What is known about (3D) steady incompressible Euler flows with compact support?

(Looking for results in a field you are not familiar with sure is tough. I had a hope to find clues starting from the famous paper of V. Scheﬀer about a flow with compact support in space-time, and from works on vortex rings I could find, but in both cases ended up empty handed. This problem was considered by some, I presume? )

incompressibleflows ? $\endgroup$ – Denis Serre Mar 1 '18 at 3:48