Viscoelastic Fluid — Oldroyd-B Polymer

Polymer stress tensor dynamics: τ/λ + (τ·∇v + ∇vᵀ·τ) = 2ηₚ/λ · D

Parameters

Wi (Weissenberg):1.0
Normal stress N₁:
Viscosity ratio:0.5
Elastic energy:
Oldroyd-B model: Maxwell fluid with solvent viscosity. Polymer dumbbells stretch in flow.

Wi = λ·γ̇ (relaxation × shear rate). Wi≫1 → large normal stresses → elastic turbulence.

Colors show |τ| stress magnitude. Ellipses show polymer conformation tensor C.