Prediction of pressure drop in non-woven filter mediä using a hagen-poiseuille model

Abstract

An accurate estimation of the pressure drop across filter media is not an eajy task considering the randomness of pore size and shape] and complexity in geometry of flow paths, particularly for non-woven depth filters. The pioneering work of Darcy laid the foundation of pressure flow characteristics through sand beds. This was followed by the work ofKozeny who proposed a theory to determine the pore size using porosity as a parameter. Carman modified the porosity-permeability relationship further to suit experimental results more closely. The pressure drop relationship using this expression is known as Kozeny-Carman equation. In the present work, the prediction results of Kozeny and KozenyCarman equations have been compared with those obtained from the Hagen-Poiseuille model which include the effect of tortuosity. The results indicate that the introduction of tortuosity effect alone can improve the prediction based on the Hagen-Poiseuille model over the Kozeny model, which underestimates the pressure drop across the filter media.