Please cite this article in press as: M. Hettel, et al., Numerical simulation of a structured catalytic methane reformer by DUO: The new computational interface for OpenFOAM ® and DETCHEM TM , Catal. Today (2015), http://dx.doi.org/10.1016/j.cattod.2015.02.011 ARTICLE IN PRESS G Model CATTOD-9476; No. of Pages 11 Catalysis Today xxx (2015) xxx–xxx Contents lists available at ScienceDirect Catalysis Today j our na l ho me page: www.elsevier.com/locate/cattod Numerical simulation of a structured catalytic methane reformer by DUO: The new computational interface for OpenFOAM ® and DETCHEM TM Matthias Hettel a,∗ , Claudia Diehm b , Henning Bonart a , Olaf Deutschmann a,b,∗ a Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Kaiserstr. 12, 76128 Karlsruhe, Germany b Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology (KIT), Kaiserstr. 12, 76128 Karlsruhe, Germany a r t i c l e i n f o Article history: Received 5 November 2014 Received in revised form 26 January 2015 Accepted 2 February 2015 Available online xxx Keywords: Methane Partial oxidation Rh, monolithic catalysts Numerical simulation CFD a b s t r a c t The catalytic partial oxidation of methane over a honeycomb-structured Rh/Al 2 O 3 coated catalyst is studied at a molar C/O ratio of unity and short-contact times experimentally and numerically. Axial species and temperature profiles inside the catalytic monolith are measured by a capillary sampling technique. A detailed numerical analysis of the flow, temperature and species concentration profiles is conducted using the new software tool DUO, which is an interface for the coupling of the computational tools OpenFOAM ® and DETCHEM TM . This interface enables the integration of detailed surface chemistry into OpenFOAM ® and allows the time-efficient calculation of structured catalysts and other catalytic reactors with multiple combined fluid and solid regions including heterogeneous reactions. In comparison with experimental data, spatial profiles of species and temperature are analyzed. The thermal boundary conditions are shown to have a strong impact on reliable predictions. Even though the characteristics of the influence of radial heat loss on the conversion can be governed, the use of a radiation model is recommended. © 2015 Elsevier B.V. All rights reserved. 1. Introduction Catalytically coated honeycomb monoliths are used in many technical processes, including pollution reduction [1,2], catalytic combustion [3–5], and selective oxidation [6–8]. Design and opti- mization of catalytic reactors is challenging due to the interaction between chemical reactions and mass and heat transfer. Modeling and simulation has been increasingly used to support research and development of catalytic reactors [9]. However, reliable numerical simulations depend on the accurate description of many interacting physical and chemical processes in the catalytic reactor. Honeycomb-structured catalytic reactors for high-temperature reforming of hydrocarbons may serve as an example. These monolithic structures often include thousands of equally sized small-diameter channels. Computational grids with high spatial resolution are needed to resolve these small structures with Com- putational Fluid Dynamics (CFD) methods in three dimensions, ∗ Corresponding authors at: Institute for Chemical Technology and Polymer Chem- istry, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe, Germany. Tel.: +49 721 608 43064; fax: +49 721 608 44805. E-mail addresses: matthias.hettel@kit.edu (M. Hettel), deutschmann@kit.edu (O. Deutschmann). which lead to a huge number of computational cells. The solu- tion would require computational times which are not viable. Furthermore, the catalytic reforming kinetics of practical fuels (e.g., gasoline, diesel) includes heterogeneous surface reactions and homogeneous gas-phase reactions consisting of thousands of elementary steps [10–12]. For each of the hundreds of species, a transport equation has to be solved in a CFD-code. The direct cou- pling of complex chemistry at this level leads to high computational costs if tractable at all. Therefore, there is a demand for efficient computational tools that, on the one hand, include all significant physical and chemical processes and, on the other hand, offer a rather inexpensive and flexible computational handling. In this paper, we present a novel developed computational tool, called DUO, serving this purpose. DUO stands for the cou- pling of the two computer codes DETCHEM TM Und (German for ‘and’) OpenFOAM ® and is a synonym for the joint utilization of these two programs. OpenFOAM ® [13] is an open source CFD tool, which enables the calculation of three-dimensional fluid and solid regions. The code recently became also popular for modeling cat- alytic reactors, e.g., by Maestri et al. [14]. By being open-source, OpenFOAM ® offers complete freedom to customize and extend its existing functionality to the user. DETCHEM TM [15] is a commercial software package, being rather inexpensive for academic pur- poses. It is specifically designed for the modeling and simulation of http://dx.doi.org/10.1016/j.cattod.2015.02.011 0920-5861/© 2015 Elsevier B.V. All rights reserved.