Non-isothermal three-dimensional developments and process modeling of composites: Flow/thermal/cure formulations and experimental validations

In the process modeling via Resin Transfer Molding (RTM) for thick composit e sections, multi-layer preforms with varying thermophysical characteristic s across the different layers, or for geometrically complex mold geometries with varying thicknesses, the assumption of a thin shell-like geometry is no longer valid. The flow in the through thickness direction is no longer n egligible and current practices of treating the continuously moving flow fr ont as two-dimensional and the temperature and cure as three-dimensional ar e not representative of the underlying physics. In view of these considerat ions, in the present study, the focus is on the nonisothermal process model ing of composites employing full three-dimensional modeling/analysis develo pments via effective computational techniques. The specific applications ar e for thick composite,geometries where the thickness is comparable to the e ther dimensions of the part. For the first time, an implicit pure finite el ement front tracking technique is employed for the transient flow/thermal/c ure coupled behavior of the full three-dimensional modeling of the moving b oundary value problem, and, due to the highly advective nature of the non-i sothermal conditions involving thermal and polymerization reactions, specia l considerations and stabilization techniques are proposed. Validations and comparisons with available experimental results are particularly emphasize d and demonstrated.