A Three-Dimensional Fluid-Structure Interaction Model for Platelet Aggregates Based on Porosity-Dependent Neo-Hookean Material

The stability of the initial platelet aggregates is relevant in both hemostasis and thrombosis. Understanding the structural stresses of such aggregates under different flow conditions is crucial to gaining insight into the role of platelet activation and binding in the more complex process of clot formation. In this work, a three-dimensional implicit partitioned fluid-structure interaction (FSI) model is presented to study the deformation and structural stress of platelet aggregates in specific blood flow environments. Platelet aggregates are considered as porous mediums in the model. The FSI model couples a fluid solver based on Navier-Stokes equations and a porosity-dependent compressible neo-Hookean material to capture the mechanical characteristics of the platelet aggregates. A parametric study is performed to explore the influence of porosity and applied body force on this material. Based on in vitro experimental data, the deformation and associated stress of a low shear aggregate and a high shear aggregate under different flow conditions are evaluated. This FSI framework offers a way to elucidate the complex interaction between blood flow and platelet aggregates and is applicable to a wider range of porous biomaterials in flow.