Parameter establishment and verification of a fabrication stress model and a thermo-kinetic cure model for filament wound structures

Abstract

Two comprehensive composite fabrication simulation computer codes have been written. These codes when coupled together have the capability to model the filament winding and curing processes for composite structures. The "Filament Winding Cure" (FWCURE) code is a thermo-kinetic model. FWCURE models the resin viscosity, percent of cure, temperature, resin flow, and layer location. As these characteristics change, they have an effect on the fiber tension within the composite. The "Winding and Curing Stress Analysis Finite Element" (WACSAFE) code models the filament winding process and predicts manufacturing stresses and strains based on material properties, lay-down tension and wind angle.

The permeability model in FWCURE requires constants that are found experimentally. The WACSAFE code requires an input tension that is equivalent to the initial spool tension minus the instantaneous tension losses.

The permeability constants and the instantaneous tension losses were found experimentally. The codes were then used to predict fiber tension, tension losses and mandrel strains for experimental test cylinders. The predictions were compared to test data.