"Platelet aggregation is a dynamic process with the potential to induce intermittent or permanent obstruction to blood flow, contributing to the development of cardiovascular diseases. This work focuses on the impact of hemodynamics on platelet aggregation, including growth, morphology, internal structure and the interaction between blood flow and platelet aggregate. The objective of this thesis is to combine the experimental data and image-based computational model to analyse the mechanism of platelet aggregation and its correlation with hemodynamics. In Chapter 2, an image-based computational model is presented to study hemodynamics inside and around platelet aggregates based on the microscopy images obtained from in vitro whole blood perfusion experiments. By employing the proposed model, Chapter 3 investigates the influence of different flow conditions on platelet aggregation, including growth, shape, and inner structure of platelet aggregates under 800, 1600, and 4000 1/s wall shear rates over time. Chapter 4 focuses on the methodology of a fluid-structure interaction model that couples a porosity-dependent compressible neo-Hookean material to a finite element blood flow simulation to resolve the deformation of platelet aggregates under specific flow conditions. A parametric study that examines the impact of porosity and body force on the mechanical properties of the materials is carried out. Chapter 5 studies flow-induced deformation and contraction of platelet aggregates. The shear modulus of neo-Hookean materials is estimated by formulating an inverse problem based on the experimental data and fluid-structure interaction model. A conclusion of the work together with an outlook are presented in Chapter 6."--