GALCIT Colloquium

This seminar highlights the versatility of shock waves as a tool to research problems from the aerospace and biomedical field. Solid rocket propellant damage is the example presented from the aerospace field. Solid rocket propellants are energetic materials that can be used as fuel in military applications to generate thrust for tactical or strategic rockets and missiles. Designing health-monitoring sensors that can quantify the structural integrity of the solid rocket propellants will be invaluable at predicting the ballistic performance, but requires additional research into the viscoelastic behavior of the solid rocket propellant at high strain rates. A study is presented where both shock tube experiments and inverse finite element simulations are performed to quantify the viscoelastic properties of inert solid rocket propellants. Digital image correlation analysis is used to validate the deformations from the simulations of the solid rocket propellant. The example from the biomedical field is cavitation bubble collapse, which is hypothesized as a mechanism of blast-induced traumatic brain injury. Blast-induced traumatic brain injury (bTBI) from explosives is the leading cause of injury among members of the U.S. Armed Forces since 2006. The mechanistic pathway which connects the propagation of a blast wave through the head with the physical and cognitive signs of brain injury remain poorly understood. A shock tube model is applied to investigate cavitation bubble dynamics under biologically realistic temperatures. Cavitation bubble formation and collapse is visually captured to quantify bubble properties such as pressure and size. The results from the cavitation study provides the experimental data needed to validate simulations investigating cavitation as a bTBI mechanism.