State-of-the-Art of Pressure Drop in Open-Cell Porous Foams: Review of Experiments and Correlations

Foam structures are a class of modern microporous media that possesses high thermal conductivity, large accessible specific surface area, and high porosities. Nowadays, industrial applications, such as filtration, heat exchange and chemical reaction, etc., utilize porous media such as open-cell foams. Knowledge of pressure drop induced by these foam matrices is essential for successful design and operation of high-performance industrial systems. The homogenized pressure drop data in the literature are widely dispersed (up two orders of magnitude) despite numerous researches has been conducted since two decades. Most of the empirical pressure drop correlations were derived using Ergun-like approach. In this view, a careful evaluation of empirical correlations as well as the relationship of intrinsic flow law characteristics (permeability and inertia coefficient) with morphological parameters is imperative. This paper presents the start-of-the-art of various pressure drop correlations as well as highlights the ambiguities and inconsistencies in various definitions of several key parameters. The applicability of the empirical correlations presented in the literature was examined by comparing them against numerically calculated pressure drop data of open-cell foams (metal and ceramic) for the porosities ranging from 0.60 up to 0.95. A comprehensive study has been conducted to identify the reasons of dispersed pressure drop data in the literature. Although substantial progress has been made in the field of fluid flow in open-cell foams, it is yet difficult to predict pressure drop data from a given set of morphological parameters.