Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Equilibrium Shock Approximation Methods and Their Applicability to Simulate Complex Shock Induced Phenomenon" By Brenden W. Hamilton Purdue MSE Ph.D. Preliminary Exam Advisor: Professor Alejandro Strachan ABSTRACT The thermo-mechanical and chemical response of materials under shock loading conditions is an important area of research for metallurgy, energetic materials, chemistry, geoscience, and astrophysics. Both experimental and theoretical research has focused on the role of shock in inducing phenomenon such as plasticity, phase transformation, failure, and chemical reactions. Due to the ultrafast timescales of these phenomena, molecular dynamics (MD) simulations are widely used to study shock. However, non-equilibrium, direct shock simulations are limited by the achievable length and time scales, with many shock-induced phenomena occurring on longer timescales than are achievable. This work aims to compare two computational approaches to simulate a material under shock loading conditions behind the shock front: The Multi-Scale Shock Technique (MSST) and the Hugoniostat. The former is derived from an extended Lagrangian with a shock pressure determined from the Rankine-Hugoniot Jump Conditions, confining the system to states along the Rayleigh Line (single shock velocity). The latter approach employs coupled volume and heat flow equations of motion that dynamically compresses the system to a desired shock pressure while varying energy to conserve the jump conditions. Both methods will be compared using the underlying theory as well as with complex test cases. Simulations are conducted for the energetic material TATB to compare shock induced volume expanding reactions to Zel'dovich-von Neumann-Döring Theory (ZND). Additionally, shock induced densification of the highly porous metal-organic framework MOF5 will be studied and compared to non-equilibrium shock simulations. Date: Thursday, April 25, 2019 Time: 10:30 A.M. Place: ARMS 3115