About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
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Symposium
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Mechanical Response of Materials Investigated through Novel In-situ Experiments and Modeling
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Presentation Title |
Multiphysics Modeling of Coupled Chemical-Thermal-mechanical Phenomena in Chemically Blown Polyurethane Foams during Manufacturing |
Author(s) |
Kevin N Long, Judith Alice Brown, Rekha R Rao, Christine C Roberts |
On-Site Speaker (Planned) |
Judith Alice Brown |
Abstract Scope |
PMDI (polymeric methylene diphenyl diisocyanate or polyurethane) foams encapsulate and protect fragile components. Complex chemical and physical processes occur during their manufacturing and service, however, that can cause undesired warpage. The ability to model these processes and predict resulting warpage is essential for production of parts with tight dimensional tolerances. We present our multi-physics model that describes the foam manufacturing process and predicts the post-manufactured residual stresses and warpage. The model involves four coupled conservation equations: energy (temperature field), momentum (foam velocity field), water concentration (blowing reaction), and polyol concentration (extent of polymerization), that are implemented in a loosely coupled finite element framework. Predicted deformations are compared with experimental measurements on foam parts during manufacturing. Results favorably predict temperature variation throughout the part, density variation, and warpage immediately following de-molding. This model complements our companion talk on long-term simulations of physical and chemical aging induced warpage in polyurethane foams. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, Polymers, Characterization |