A framework for predicting the flow behaviour of liquid foams enhanced by xanthan gum and sodium carboxymethyl...

Predicting the flow of foam across different geometries is a critical challenge, particularly when the continuous phase is a polymer-based non-Newtonian fluid. To address this challenge, foams were prepared using two distinct non-Newtonian fluids. In rotational rheometry, the power-law and Bingham models adequately described the constitutive behaviour of non-Newtonian fluid-based foams. Afterwards, quantitative relationships between the structure of the foam (bubble size and expansion ratio), the constitutive behaviour of the solutions, and the constitutive behaviour of the foam (yield stress, consistency coefficient, and flow index) were established. In pipe, the friction factor-Reynolds number relationship for non-Newtonian fluid-based foams exhibits nonclassical scaling with an exponent of 0.84, significantly deviating from 1 for Newtonian fluid-based foams. After incorporating a wall slip correction, the coefficient increases from 16.8 to 22.9. These findings indicate that the friction factor-Reynolds number correlation varies significantly with the properties of the base fluid. Moreover, models for apparent viscosity and stress-shear rate that integrate the bubble diameter and polydispersity index successfully bridge the gap between benchtop rheometry and industrial-scale pipeline flow. This study provides a framework that moves beyond configuration-specific correlations, and offers predictive power for the design of processes in several areas, including food processing and enhanced oil recovery.