Industrial-Scale Modeling of Herschel-Bulkley (Yield Stress) Fluids

The suitability of lattice-Boltzmann-based CFD for modeling Herschel-Bulkley fluid is examined. Under the Herschel–Bulkley model, the strain experienced by a fluid is related to the stress via a yield shear stress, flow consistency, and flow index. Although common in industrial practices, the yield stress-induced discontinuity in the constitutive relationship is difficult to model using time-averaged, RANS-based CFD. The time-accurate nature of the lattice-Boltzmann approach, combined with the high spatial resolution it affords, enables a DNS approach to modeling momentum transport through such systems. Here we assess the industrial suitability of this lattice-Boltzmann DNS approach for modeling Herschel–Bulkley fluids, as applied to draining storage tanks, flow through pipes, and flow inside agitated systems.