Materials Engineering Seminar – New Mexico Tech Calendar
Laura de Sousa Oliveira from the University of Wyoming will present the material technology seminar. Your talk is “Atomistic Modeling of Phonon Transport”.
Friday, February 12th, 12 noon in Speare 113
The ability to control and manipulate heat goes hand in hand with human progress. This was the case in the prehistory “when we mastered fire for cooking, heating and defending” and it is still true today. As devices get smaller and our ability to nanostructurize materials to predict and control heat transport in next-generation materials and devices, it is important to develop an atomistic understanding of heat transport. My research so far has focused on heat transport at the atomistic level, including classical molecular dynamics, ab initio approaches, and heuristic models in a variety of materials. In this talk I will discuss heat transport in three types of bulk solids with a variety of functions, applications, and transport properties: graphite, nanoporous silicon, and organic metal frameworks. The applications for these materials range from nuclear technology to the This applies, among other things, to the generation and storage of energy. Classical molecular dynamics is particularly useful for assessing heat transport in defect-laden structures. For example, in order to expand our knowledge of the development of the microstructure of graphite during operation in a nuclear reactor moderated with graphite, I am investigating how different point defects and their concentrations affect heat transport. While high thermal conductivity is ideal for a core moderator, thermoelectric applications require very low thermal conductivities. Thermoelectric devices that convert temperature differences into electricity and vice versa are a promising technology for waste heat recovery ry “about two thirds of all energy generated is lost as waste heat! The introduction of nanopores drastically reduces the thermal conductivity of a material, but there is still no clear understanding of this why this is so. Using large-scale simulations of molecular dynamics (of hundreds of thousands of atoms), I investigate the influence of pore configuration on heat transport in order to identify the main mechanisms for reducing thermal conductivity in porous materials. Finally, we take a brief look at the Heat Transfer in Organometallic Frameworks (MOFs). MOFs are highly modular and have large surface areas and therefore show promise for numerous applications including hydrogen storage and carbon sequestration Thermal conductivity is proposed as a heuristic for rapidly assessing heat transport in flexible MOFs, and a quantum-based approach is implemented to investigate deviations from the heuristic. This leads to the discovery of emergent Rattler modes and heat focusing properties that can be turned on and off.