Events Calendar

 
Seminar

"Microstructure-property relationships for advanced functional materials" by Prof. Volker Schmidt, Universität Ulm

Friday, 01 February 2019, 13:30-15:00
KIT, Campus Nord
Institute of Nanotechnology
Bldg. 640 Seminar Room 0-167
Hermann-von-Helmholtz-Platz 1
76344 Eggenstein-Leopoldshafen

Talk given by

Prof. Volker Schmidt

Institut für Stochastik

Universität Ulm

 

Abstract:

We are going to introduce the concept of virtual materials testing, i.e., the combination of stochastic 3D microstructure modeling, image analysis and numerical simulations, which is used to elucidate microstructure-property relationships. Using stochastic 3D models, one can generate a large variety of virtual, but realistic microstructures with little computational effort. Image analysis is used to determine corresponding microstructure characteristics, while numerical simulations allow for a simulation of effective macroscopic properties as effective conductivity and permeability, which are important in applications with respect to functional materials as solid oxide fuel cell or battery electrodes.

 

In this talk, we investigate quantitative relationships between microstructure characteristics and effective conductivity as well as permeability for virtual microstructures, generated by a versatile, graph-based microstructure model introduced in [1]. As the main microstructure characteristics, we consider phase volume fractions, mean geodesic tortuosity, two “hydraulic radii” for characterizing the length scales of heterogeneities, and a “constrictivity” parameter that describes bottleneck effects. We modify the formula originally developed in [2] for predicting the effective conductivity and propose a formula for permeability [3]. For the latter one, different geometric definitions of the hydraulic radius are compared. Finally, we obtain empirically derived analytical formulas expressing effective conductivity and permeability by purely geometric characteristics. These formulas are validated using image data representing the microstructure of solid oxide fuel cells, which is obtained by FIB-SEM tomography.

References

 

[1] G. Gaiselmann, M. Neumann, O. M. Pecho, T. Hocker, V. Schmidt, and L. Holzer. Quantitative relationships between microstructure and effective transport properties based on virtual materials testing. AIChE Journal, 60(6):1983–1999, 2014.

[2] O. Stenzel, O. M. Pecho, L. Holzer, M. Neumann, and V. Schmidt. Predicting effective conductivities based on geometric microstructure characteristics. AIChE Journal, 62:1834–1843, 2016.

[3] M. Neumann, O. Stenzel, F. Willot, L. Holzer, and V. Schmidt. Quantifying the influence of microstructure on effective conductivity and permeability: virtual materials testing. submitted, 2019+.

 
 
This event is part of the eventgroup INT Talks
Organizer
Dr. Christian Kübel
Institute of Nanotechnology (INT)
Karlsruhe Institute of Technology (KIT)
Eggenstein-Leopoldshafen
Mail: christian kuebel does-not-exist.kit edu
Targetgroup
Interested / Everyone
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