Multiscale simulation: connecting statistical physics to engineering applications and materials properties

Special Seminars

Speaker: Jean-Louis Barrat, University of Joseph Fourier, Grenoble, France
Date & Time: October 1, 2013 16:00 - 17:00
Location: UBC, Michael Smith Labs, Lecture Theatre 102
Local Contact: Joerg Rottler
Intended Audience: Public

The development of nanosciences raises new challenges and opportunities for material sciences. One may broadly say that these new challenges fall in two different categories. Firstly, how do the properties of matter evolve as a function of the scale under consideration, and in particular when the dimensions of devices fall into the nanoscale range ? While this question is most often discussed for electronic properties, it also arises for many other usage properties of materials, in particular mechanical, flow or thermal properties. Second, can one make use of a better knowledge of the nanoscale properties to gain a better understanding of, and possibly improve, macroscopic properties of materials that involve internal structures at various scales ?

These questions are intimately related to the development of multiscale modelling approaches, a rather broad domain which is understood here as methods that allow one to establish relevant links between phenomena taking place at different scales of description, and assess the validity of each description at different length and time scales. In this spirit, the presentation will address problems that are of current interest to the materials science and engineering community, and involve particular challenges in bridging the length and time scales gaps, such as interfacial transfers or mechanical properties of nanostructured materials.

These topics offer very similar challenges to the researcher willing to develop multiscale modelling approaches:

• They are giving rise to an increasing experimental activity within the physics and engineering community, with growing efforts to carry experiments on well characterized, idealized systems.
• They require a combination or ideas from continuum media with an atomic description of elementary processes at the nanometer scale. Between the continuum and atomic scales intermediate “mesoscales” that require a specific understanding of each system are present.
• They are extremely open in terms of methods, with a clear need to develop schemes at a “mesoscopic” level to bridge the time and length scale gap, going beyond the usual atomistic or continuum media approaches.

The presentation will connect the fundamental questions that the physicist wants to address, such as the description of elementary processes that govern heat or momentum transfer from surfaces and across molecules, deformation of amorphous materials, to more applicative questions such as flow in microchannels, heat transfer in nanofluids or nanocomposites mechanical properties.