Three Dimensional Simulation of Moisture Diffusion in Thick Composites
Long term moisture exposure has been shown to affect the mechanical performance of polymeric composite structures. This reduction in mechanical performance must be accommodated for during product design in order to ensure long term structure survival. In order to determine the long-term moisture effects on composite components, representative parts are commonly tested after having been exposed to an accelerated moisture conditioning environment. Accelerated moisture conditions are established in order to rapidly drive moisture into test specimens simulating worst-case long term exposure scenarios. Currently accepted methodologies for analyzing the time required to condition specimens are limited, allowing only simple geometry and an assumption that diffusivity rates are independent of the flow path or direction. Therefore, a more advanced finite element method is desired. In the current work, a three dimensional model is developed and implemented in commercial finite element code. The parametric study has been conducted for complex shapes, moisture diffusion pathways, and varying moisture and temperature conditions. Finite element results are validated with a one-dimensional analytical model and experimental results. The ultimate goal for this research is to determine exposure times for accelerated conditioning that produce the most accurate moisture distribution with the part and minimize over-conditioning of the laminate.
N. Roe et al., "Three Dimensional Simulation of Moisture Diffusion in Thick Composites," International SAMPE Technical Conference, Society for the Advancement of Material and Process Engineering (SAMPE), Jan 2012.
2012 SAMPE International Symposium and Exhibition
Mechanical and Aerospace Engineering
Keywords and Phrases
Commercial Finite Element Codes; Complex Shades; Composite Components; Exposure Time; Finite Element; Flow Path; Long Term Exposure; Mechanical Performance; Moisture Conditioning; Moisture Conditions; Moisture Diffusion; Moisture Effects; Moisture Exposure; Parametric Study; Simple Geometries; Temperature Conditions; Term Structure; Test Specimens; Thick Composites; Three Dimensional Simulators; Three-Dimensional Model
Article - Conference proceedings
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