This ONR-supported effort is is a collaborative project between the the Colorado School of Mines, Naval Research Laboratory, California Institute of Technology, and Fluent, Inc.

Colorado School of Mines: Profs. ,

Naval Research Laboratory: Drs. Richard Mowrey, Brett Dunlap

Caltech: Prof. David G. Goodwin

Fluent: Drs. Graham Goldin, Jay Sanyal

Other CSM research faculty and students: Huayang Zhu, Hans Carstensen, Andrew Colclasure

The objective of this effort ONR-sponsored effort is to develop significant new modeling capabilities to support research in the analysis, design, and optimization of electrochemical systems. High-priority applications include fuel cells, membrane reactors, batteries, fuel reformers, and corrosion processes. These systems are complex at the engineering level and rely on chemical processes that are not well understood at the fundamental level . There is great value in creating tools to enable the quantitative incorporation of fundamental chemistry into engineering practice.

The effort is built on parallel, yet highly coupled and interactive, tracks:

• Develop and apply quantum-mechanical (QM) methods to create appropriate potential energy surfaces (PES).
• Develop and apply quantum dynamics (QD) simulations that use the results of QM calculations to identify critical reaction pathways, including charge-transfer processes.
• Develop chemical reaction mechanisms for both catalytic and gas-phase processes that are informed by the QM calculations and can be coupled to the charge-transfer processes.
• Predict surface thermodynamic properties on the basis of the QM calculations.
• Extend computational fluid dynamics (CFD) software to incorporate elementary electrochemistry,
• Validate the models and the approach using data from solid-oxide fuel cells (SOFC).

The objectives are very broad and far-reaching. The new interoperable research tools will be very general and widely applicable. The program will maintain focus and coordination using SOFCs that operate on logistics hydrocarbon fuels.

In very broad terms we organize the approach in terms of modeling at appropriate length scales and creating bridges that facilitate communication between models at widely disparate scales (Fig. 1). At the microscale (atomic scale) we develop quantum mechanical simulations to investigate elementary chemical processes. Chemical kinetics reaction mechanisms form the bridge to the mesoscale (here concerned with three-phase interfaces on the order of a micron). At the mesoscale, direct experimental data are available. Thus models and mechanisms can be refined and validated. Computation at the scale of engineered systems usually requires discretization on the order of a millimeter or larger. Thus information acquired at the mesoscale is difficult to apply directly. We propose to develop homogenization approaches to upscale mesoscale information to the macroscale. The five major tasks in this proposal are to model at appropriate scales (microscale, mesoscale, and macroscale) and to develop and apply the communication bridges (reaction mechanisms and homogenization).

Modeling and Simulation Tools for Chemical and Electrochemical Systems: Bridging between Atomistic Fundamentals and System Engineering