Capillary transport is the predominant phenomena in a wide range of absorbent systems, such as absorbent pads, tissue, paper, feminine products and diapers. Many absorbent articles are composites of nonwovens and other porous materials that have extremely complex design and intricate pore geometry. This heterogeneous structure can significantly influence the flow and absorbancy characteristics. Important effects to consider include capillary pressure, liquid saturation and capillary evaporation/condensation.