Single process production of 3D nonwoven shell structures - Part 1: Web forming system design using CFD modeling

Abstract

The paper describes the application of CFD modeling for designing a nonwoven air-laying system to produce 3D webs from staple fibers. The fibers are opened by an opening unit and carried by airflow to 3D porous moulds to form the web. The most critical parameter of the air duct is the divergent angle that in theory should be less than 7° to avoid airflow vortex. The airflow angle to the surface of a 3D mould is different at different points. To produce a 3D web with acceptable thickness uniformity, the airflow through the moulds must be regulated. This can be achieved by modifying the airflow resistance distribution through the 3D mould.