MAE & MSE Special Talk: Bo Li, Predictive modeling and simulation of High Energy Density (HED) dynamic response of materials

Graduate Aerospace Laboratories, California Institute of Technology, Pasadena, California

Note location: Scott Labs E100

Abstract

Numerical modeling of the response and failure of materials under extreme conditions (extremely high pressure, temperature and strain rate) is a long-standing challenge in computational mechanics. It places exact demands on numerical solvers, physics-based multiscale material models and high performance computing. This talk will present how we address these challenges. A novel meshfree solver, the Optimal Transportation Meshfree (OTM) method based on a combination of Optimal Transportation theory, material point sampling and Local Maximum Entropy interpolation, is proposed to overcome the difficulties in the simulation of High Energy Density (HED) dynamic response of materials. A variational material point failure algorithm is presented for predicting the fracture and fragmentation and is mathematically provable to converge to the solution of Griffith fracture theory in brittle materials. We take the conventional verification and validation (V&V) analysis to evaluate the performance of our methods as well as model-based UQ analysis to determine the error and uncertainties of our models in the applications of terminal ballistics and hypervelocity impacts. The range and scope of the method is also demonstrated in the monolithic Lagrangian Fluid-Structure-Interaction (FSI) simulations of human arterial blood flows with breakup plaque. The second part of this talk will focus on the multiscale material modeling and multiscale modeling of ductile failure in the OTM method. A thermomechanical concurrent multiscale computational framework will be introduced that allows for direct numerical simulation of the polycrystalline structure coupled with void growth, single crystal plasticity, phase transformation, physics-based hardening and rate sensitivity laws, and First principles calculations of the Equation of State and material properties. Due to the complexity nature of this problem, I will also touch upon the development of the extreme Optimal Transportation Meshfree (XOTM) method to take advantage of high performance computing systems.

Though not part of the MSE 7895 Seminar & Colloquium series, all are encouraged to attend.