Foaming Prediction in Pure Liquids from Dimensionless Numbers Inspired by the Theory of Fluid Behavior for Drops

Foaming prediction is essential for the rational selection of materials and design processes in diverse industries ranging from bioprocesses to gas processing facilities. Existing foaming prediction models lack the generality needed for a wide range of materials and overlook the foaming in pure liquids. This work introduced a novel approach to predict foaming in pure liquids based on their density, surface tension, and viscosity, calculated through Reynolds (Re) and Ohnesorge (Oh) numbers. A foaming prediction map, representing a plot between these numbers, was constructed by leveraging the theory governing the behavior of fluid drops. This map delineated distinct non-foaming regions alongside a foaming region, serving as a binary classifier for foaming predictions. The map was fitted and validated with shake test experiments on 47 liquids, demonstrating effective predictions, except for a specific region characterized by small Oh and large Re numbers. This region corresponded to relatively low foam stability and high turbulence, making predictions challenging for liquids in this category.