Hierarchical petascale simulation framework for stress corrosion cracking

The goal of this SciDAC project is to develop a scalable parallel and distributed computational framework consisting of methods, algorithms, and integrated software tools for: 1) multi Tera-to-Petascale simulations with quantum-level accuracy; 2) multimillion-to-multibillion-to-trillion atom molecular dynamics (MD) simulations based on density functional theory (DFT) and temperature dependent model generalized pseudopotential theory; 3) quasicontinuum (QC) method embedded with classical atomistic and quantum simulations based on DFT; and 4) accelerated molecular dynamics (AMD) coupled with hierarchical atomistic/QC simulations to reach macroscopic length and time scales relevant to SCC. Scalability is being achieved beyond 105 processors through linear-scaling algorithms and performance-optimization techniques. We are employing automated model transitioning to embed higher fidelity simulations concurrently inside coarser simulations only when and where they are required. Each scale and model has well-defined error bounds with controlled error propagation across the scales and models to estimate uncertainty in predictions.