Modeling of Material Degradation using Decoupled Finite Element Approaches: Applications to Localized Corrosion of Iron Alloys and Hydraulic Fracture of Glaciers

Abstract

Degradation of materials poses a significant threat to the safety and stability of both man-made and natural materials and structures, and is generally driven by coupled chemical and physical processes. Complementary to experiments, numerical modeling studies are essential to better understand the degradation process and to predict the failure of materials. However, high-fidelity mathematical models describing the physics of material degradation require solving highly-nonlinear, coupled partial differential equations (PDEs). Consequently, decoupled or staggered approaches can be more robust compared to coupled or monolithic approaches for solving these models. This dissertation presents novel decoupled approaches to model the corrosive dissolution of iron alloys and hydraulic fracture in glaciers, and discusses their implementation using the standard finite element method. Simulation studies, including verification and validation studies, are conducted to establish the flexibility, efficiency, and accuracy of the decoupled finite element approaches and address specific science questions in the areas of corrosion and glaciology.