303v Cfd Model for Performance Analysis of Nonwovens Absorbent Media

Peter Spicka, Fluent Inc., 10 Cavendish Court, Lebanon, NH 03766

Competitive pressure in the consumer product industry requires reducing time-to-market to several months. Besides the ability to launch new products – wipes, protective clothing, feminine hygiene and baby diapers in a short time, product performance is the key to the overall product success. Modeling of unsaturated liquid flow can address design performance issues at the early stages of design cycle and it can articulate potential needs for design modifications related to both product performance and manufacturing issues. The scope of the modeling involves wide range of flow regimes and media configuration. For example, the source of the liquid can be a liquid droplet sitting on the top of the composite/sandwich nonwovens structure or a liquid jet hitting the surface of the pad. The primary interest in studying the liquid flow in such media is to study spreading of liquid inside the voids formed by fibrous material and physical bounding of moisture due to sorption phenomena. The model is based on the volume-averaged properties of nonwovens media and allows customization of many parameters including sorption isotherms. A comprehensive description of the related physics and model implementation in practical examples provides important insight on issues related to performance of nonwovens products.