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Numerical modeling of an all vanadium redox flow battery

Clausen, Jonathan; Martinez, Mario J.; Brunini, Victor; Moffat, Harry K.

We develop a capability to simulate reduction-oxidation (redox) flow batteries in the Sierra Multi-Mechanics code base. Specifically, we focus on all-vanadium redox flow batteries; however, the capability is general in implementation and could be adopted to other chemistries. The electrochemical and porous flow models follow those developed in the recent publication by [28]. We review the model implemented in this work and its assumptions, and we show several verification cases including a binary electrolyte, and a battery half-cell. Then, we compare our model implementation with the experimental results shown in [28], with good agreement seen. Next, a sensitivity study is conducted for the major model parameters, which is beneficial in targeting specific features of the redox flow cell for improvement. Lastly, we simulate a three-dimensional version of the flow cell to determine the impact of plenum channels on the performance of the cell. Such channels are frequently seen in experimental designs where the current collector plates are borrowed from fuel cell designs. These designs use a serpentine channel etched into a solid collector plate.

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TYPE SAND Report YEAR 2013
DOIOSTI

GOMA 6.0 - A Full-Newton Finite Element Program for Free and Moving Boundary Problems with Coupled Fluid/ Solid Momentum, Energy, Mass, and Chemical Species Transport: User’s Guide

Sackinger, Philip A.; Noble, David R.; Notz, Patrick K.; Roberts, Scott A.; Rao, Rekha R.; Chen, Ken S.; Sun, Amy C.; Hopkins, Matthew M.; Subia, Samuel R.; Hopkins, Polly L.; Moffat, Harry K.; Roach, Robert A.

Goma 6.0 is a finite element program which excels in analyses of multiphysical processes, particularly those involving the major branches of mechanics (viz. fluid/solid mechanics, energy transport and chemical species transport). Goma is based on a full-Newton-coupled algorithm which allows for simultaneous solution of the governing principles, making the code ideally suited for problems involving closely coupled bulk mechanics and interfacial phenomena. Example applications include, but are not limited to, coating and polymer processing flows, super-alloy processing, welding/soldering, electrochemical processes, and solid-network or solution film drying. This document serves as a user's guide and reference.

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TYPE SAND Report YEAR 2013
DOIOSTI

Computational thermal, chemical, fluid, and solid mechanics for geosystems management

Martinez, Mario J.; Red-Horse, John R.; Carnes, Brian; Mesh, Mikhail; Field, Richard V.; Davison, Scott M.; Yoon, Hongkyu; Bishop, Joseph E.; Newell, Pania; Notz, Patrick K.; Turner, D.Z.; Subia, Samuel R.; Hopkins, Polly L.; Moffat, Harry K.; Jove-Colon, Carlos; Dewers, Thomas; Klise, Katherine A.

This document summarizes research performed under the SNL LDRD entitled - Computational Mechanics for Geosystems Management to Support the Energy and Natural Resources Mission. The main accomplishment was development of a foundational SNL capability for computational thermal, chemical, fluid, and solid mechanics analysis of geosystems. The code was developed within the SNL Sierra software system. This report summarizes the capabilities of the simulation code and the supporting research and development conducted under this LDRD. The main goal of this project was the development of a foundational capability for coupled thermal, hydrological, mechanical, chemical (THMC) simulation of heterogeneous geosystems utilizing massively parallel processing. To solve these complex issues, this project integrated research in numerical mathematics and algorithms for chemically reactive multiphase systems with computer science research in adaptive coupled solution control and framework architecture. This report summarizes and demonstrates the capabilities that were developed together with the supporting research underlying the models. Key accomplishments are: (1) General capability for modeling nonisothermal, multiphase, multicomponent flow in heterogeneous porous geologic materials; (2) General capability to model multiphase reactive transport of species in heterogeneous porous media; (3) Constitutive models for describing real, general geomaterials under multiphase conditions utilizing laboratory data; (4) General capability to couple nonisothermal reactive flow with geomechanics (THMC); (5) Phase behavior thermodynamics for the CO2-H2O-NaCl system. General implementation enables modeling of other fluid mixtures. Adaptive look-up tables enable thermodynamic capability to other simulators; (6) Capability for statistical modeling of heterogeneity in geologic materials; and (7) Simulator utilizes unstructured grids on parallel processing computers.

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TYPE SAND Report YEAR 2011
DOIOSTI
Results 26–50 of 81
Results 26–50 of 81
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