Thermomechanical peridynamic analysis with irregular non-uniform domain discretization [Thermomechanical peridynamic analysis with non-uniform domain discretization]
Non-uniform discretization of the solution domain in models based on peridynamic theory can improve computational efficiency by allowing for local refinement where needed for accuracy, and helps remove the effect of mesh bias in the simulations. However, the use of non-uniform discretization and a variable horizon requires consideration of possible unbalanced interactions between two material points, adjustment of peridynamic material parameters, and arbitrary shapes of interaction domains. This study presents a modification to the original peridynamic theory in which the strain energy associated with an interaction between two material points is split according to the volumetric ratio arising from the presence of non-uniform discretization and a variable horizon. It also removes the requirement for correction of peridynamic material parameters due to surface effects. Furthermore, the accuracy of this approach is verified against benchmark solutions, and its applicability to engineering problems is demonstrated by considering thermally induced cracking in a nuclear fuel pellet.