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DOE OSTI · 1737537

An Adaptive-Mesh-Refinement Based Computational Tool for Simulating Catalysis at Mesoscale

Sitaraman, Hari·Bharadwaj, Vivek (ORCID:0000000158519807)·Pecha, Brennan (ORCID:0000000208948504)·Ciesielski, Peter N. (ORCID:0000000333609210)·Crowley, Michael F.
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Abstract

In this work, we present a computational tool for mesoscale applications using open-source exascale- computing compatible adaptive-mesh-refinement (AMR) library, AMReX [2]. AMReX is software library that enables development of application solvers with block-structured Cartesian AMR. Our tool has capabilities to include realistic geometry representation, chemical species transport, reactions and thermodynamics that are critical for capturing mesoscale physics. A significant achievement is the ability of our solver to automatically import electron microscopy data in the form of a stereolithography (STL) or pixelated file format (mrc, tiff) without undergoing the tedious task of unstructured mesh generation. This feature allows for rapid simulation of catalyst particles with complex morphologies using an immersed-boundary formulation. The use of AMR allows for higher resolutions at catalyst surface interfaces, which in turn provides an accurate description of surface reactions and transport. Our solver uses a hybrid distributed and shared memory parallelism (OpenMP/GPU-based) with which strong scaling up to 10,000 processors for realistic catalyst particle simulations have been demonstrated.

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BIOMASS FUELS,MATHEMATICS AND COMPUTINGcatalysiscomputational fluid dynamicsmesoscale modelingreacting flow

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Sitaraman, Hari, Bharadwaj, Vivek (ORCID:0000000158519807), Pecha, Brennan (ORCID:0000000208948504), Ciesielski, Peter N. (ORCID:0000000333609210), Crowley, Michael F.. 2020-12-07. An Adaptive-Mesh-Refinement Based Computational Tool for Simulating Catalysis at Mesoscale. https://www.osti.gov/biblio/1737537

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