Elastic turbulence occurs in dilute polymer solutions at low Reynolds number — driven not by inertia but by elastic stresses in stretched polymer chains.
The Weissenberg number Wi = τ·γ̇ compares relaxation time τ to flow timescale. Above a critical Wi ≈ 3–5, polymer coils stretch chaotically, creating random vortices and mixing far exceeding Newtonian flows.
Discovered by Groisman & Steinberg (2000), elastic turbulence enables efficient mixing in microfluidics without inertial forces.