Turbulence is hard to control. Its ephemeral nature prevents us from treating it as an ordinary state of matter. Here we create a stationary and isolated blob of turbulence using only elemental building blocks: vortex rings. The turbulence is confined in a spherical region, surrounded by a quiescent environment, initiated and sustained by vortex rings. Crucially, vortex rings can be endowed with conserved quantities such as energy and helicity, which can be transferred to the turbulent state. Using 2D particle image velocimetry and 3D particle tracking velocimetry, we demonstrate how confinement of turbulence occurs when vortex rings repeatedly collide, in contrast to coherent vortex reconnections. The pathlines depict the difference between these states of flow.
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