Oxidation and reforming reaction rate data pertaining to micro-structured heterogeneous reaction systems under laminar flow conditions
Description
The oxidation and reforming reaction rate data are obtained for micro-structured heterogeneous reaction systems under laminar flow conditions. The reactor system comprises two separate sets of flow channels, which are located between spaced, highly heat-conductive metal or ceramic separating walls. The medially located, bi-catalytic separating walls have different catalysts on opposed surfaces. These catalysts are selected for the particular reaction taking place in the adjacent reaction zone. The reactor provides for continuous and simultaneous reaction of two different process reaction streams in the channels defined between the walls, wherein a first process reaction stream undergoes a high temperature exothermic reaction in the first set of flow channels and a second process reaction stream undergoes an endothermic heat-consuming reaction in the second set of flow channels separated from the first set of flow channels by the heat transfer separating walls. More specifically, the reactor system includes a set of reforming channels for steam reformation of methanol and a set of oxidation channels for heating the reactor system to operating temperature. A separating wall therefore separates two adjacent reaction zones and also functions to transfer heat from the oxidation occurring at the catalyst surface in the oxidation zone directly to the reforming catalyst coated on the opposed surface. The reactor system is operated using excess air and water steam. Methanol and air are mixed homogeneously and the mixture is fed directly into the oxidation channels in a specific ratio. Preferably, excess water steam is provided to the reactor to increase efficiency and to maintain operability, for example, to prevent carbon formation. The heat release and consumption due to a surface reaction must be included in the model. Endothermicity or exothermicity of surface reactions contribute to the energy balance at an interface. Heat fluxes in the solid phase are balanced by chemical heat release at the surface. The porous media model is applied to the computational domains of the catalytically active layers. The porous media involve surface reactions. Each porous medium is modeled by adding a momentum source term to the standard momentum conservation equations. The source term is composed of two parts: a viscous loss term and an inertial loss term. Contributor: Junjie Chen, E-mail address: koncjj@gmail.com, ORCID: 0000-0002-5022-6863, Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China
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Steps to reproduce
ANSYS FLUENT is applied to define the terms in the equations relating to conservation, thermodynamics, chemical production rates, and equation of state, and then combine the results to define the problem involving surface chemistry. To solve the conservation equations, a segregated solution solver with an under-relaxation method is used. The segregated solver first solves the momentum equations, then solves the continuity equation, and updates the pressure and mass flow rate. The energy and species equations are subsequently solved and convergence is checked.