A semi-analytical closure approximation for pipe flows of two Herschel-Bulkley fluids with a stratified interface

作者：Moyers Gonzalez M; Alba K; Taghavi S M; Frigaard I A^*

来源：Journal of Non-Newtonian Fluid Mechanics, 2013, 193: 49-67.

DOI：10.1016/j.jnnfm.2012.06.008

• Multi-layer flow
• Stratified interface
• Yield stress
• Herschel-Bulkley fluid
• Lubrication model
• Displacement flow

We propose a semi-analytical closure approximation to the stratified flow of two Herschel-Bulkley fluids flowing along a circular pipe. The closure proposed appears to approximate the volumetric fluxes within 10-15% over a broad range of rheological parameters and interface heights. Accuracy is diminished at more extreme viscosity ratios when the less viscous fluid is in a thin layer. We demonstrate that the closure is able to give a good prediction of displacement front velocities in the viscous regime, comparing well with experimental values, and can be used for approximating other design features of a displacement process, e.g. the maximal static wall layer (in the case of a yield stress fluid) and the minimal flow rate to prevent backflow.

• 出版日期2013-3