This is a past event.

Chemical Engineering Research Seminar

Dr. Karl Hammond

Associate Professor of Chemical Engineering
University of Missouri

Abstract

Nuclear fusion has nearly limitless potential as an energy source, provided we can solve the substantial problem of keeping fusion reactions going for longer than a few seconds outside the gravitational well of a star. With advances in plasma physics, releasing energy through nuclear fusion may finally be more than a fantasy, but these advances have created or revealed substantial materials science challenges for plasma-facing components in potential fusion reactors. Hydrogen and helium from the plasma will embed themselves in the materials as they exit the plasma at high velocity, and their low solubility will lead to embrittlement, surface deformation, and changes in material properties such as thermal conductivity and yield strength. Designing future fusion reactors will require a host of modeling and simulation efforts, including estimates of helium and hydrogen transport rates, knowledge of the mechanisms of surface deformation, correlations for bubble sizes and densities, and so forth. This talk will discuss “computer experiments” that are designed to both elucidate mechanisms of processes taking place in plasma-facing and irradiated materials and to provide benchmarks for more coarse-grained models of helium and hydrogen transport and accumulation in plasma-facing materials.

The primary focus will be on what we call “large-scale molecular dynamics”: simulations of on the order 1 million to 10 million atoms for simulated times of approximately 1 microsecond, with special attention to mathematical models of the thermodynamics, kinetics, and transport phenomena associated with process that occur in plasma-facing tungsten.

Bio

Karl Hammond was born and raised in Rochester, Minnesota. He obtained a BS in chemical engineering from Caltech, where he did undergraduate research in process modeling and control under Richard Murray and David Goodwin and spent a summer making zeolites under Saleh Elomari at Chevron. He later earned a PhD in chemical engineering from the University of Massachusetts Amherst, where he studied experimental characterization and computational modeling of zeolites and other porous materials under Scott Auerbach and Curt Conner. He then served for a semester as a lecturer at UMass Amherst, followed by a postdoc at the University of California, Berkeley and the University of Tennessee, Knoxville, where he studied plasma-facing and irradiated materials under Brian Wirth. He joined the Department of Chemical Engineering (later merged with Bioengineering to form Biomedical, Biological, and Chemical Engineering and recently renamed to Chemical and Biomedical Engineering) at the University of Missouri’s main campus in Columbia, Missouri in 2014. Prof. Hammond is also an avid musician: he plays the viola, sings regularly, and at one point played the oboe and English horn as well. He has acted in two operas, two musicals, and several musical revues.