Phenolic Resin Thermal Response and Fracture in a Bonded-Particle Model

Phenolic resins are common to many ablative materials for thermal protection systems (TPS). Infusing a fiber reinforcement typically in the form of a network (eg PICA), or a weave (eg 3MDCP) is particularly useful for low- and mid-density ablators. Continuum models of phenolic-infused ablators successfully model the material response during entry and size heat shields. Microstructure-resolved models of the composite components successfully calculate material properties and structure-property relationships. The fibers and resin in ablators go through large microstructural changes during fracture or large thermal gradients, for example. Particle/non-meshed/Lagrangian models can capture large microstructural changes.

We present simulations using a bonded-particle model implemented in a Lagrangian framework. We review the role of coarse-graining and bond-network characteristics for simulating a polymeric resin. We calculate the fracture strength, fracture surface, and thermal conductivity of the model. Ultimately, we assess the ability of these models to capture the effects of phenolic resin properties, to model infused materials and to transfer to continuum models.