A good understanding of woven fiber preform permeabilities is critical in the design and optimization of the composite molding processes, yet these issues remain unresolved in the literature. Many have attempted to address permeability predictions for flat undeformed fiber preform, but few have investigated permeability variations for complex three-dimensional molds. In this study, the objectives are to: (i) first provide a brief review of existing methods for the prediction of the fiber mat permeability; (ii) postulate a more realistic representation of a unit cell to account for such fabric structures as crimp, tow spacing and the like; and (iii) apply computational approximations for predicting effective permeabilities for use in the modeling of structural composites processes. The Stokes equation is used to model the flow in the inter-tow region of the unit cell, and in the intra-tow region, the Brinkman's equation is used. Preliminary permeability prediction calculations are performed for a three-dimensional unit cell model representative of PET 61 woven fabric. The results showed good agreement with experimental data published in literature.
|Original language||English (US)|
|Title of host publication||American Society of Mechanical Engineers, Applied Mechanics Division, AMD|
|Number of pages||16|
|State||Published - 1999|
|Event||Application of Porous Media Methods for Engineered Materials - 1999 (The ASME International Mechanical Engineering Congress and Exposition) - Nashville, TN, USA|
Duration: Nov 14 1999 → Nov 19 1999
|Name||American Society of Mechanical Engineers, Applied Mechanics Division, AMD|
|Other||Application of Porous Media Methods for Engineered Materials - 1999 (The ASME International Mechanical Engineering Congress and Exposition)|
|City||Nashville, TN, USA|
|Period||11/14/99 → 11/19/99|
Bibliographical noteFunding Information:
The authors are very pleased to acknowledge support in part by Battelle/US Army Research Office (ARO) Research Triangle Park, North Carolina, under grant number DAAH04-96-C-0086, and by the Army High Performance Computing Research Center (AHPCRC) under the auspices of the Department of the Army, Army Research Laboratory (ARL) cooperative agreement number DAAH04-95-2-0003/contract number DAAH04-95-C-0008. The content does not necessarily reflect the position or the policy of the government, and no official endorsement should be inferred. Support in part by Dr. Andrew Mark of the Integrated Modeling and Testing (IMT) Computational Technical Activity and the ARL/MSRC facilities is also gratefully acknowledged. Special thanks are due to the CICC Directorate and the Materials Division at the US Army Research Laboratory (ARL), Aberdeen Proving Ground, Maryland. Other related support in the form of computer grants from the Minnesota Supercomputer Institute (MSI), Minneapolis, Minnesota is also gratefully acknowledged.