Danish Technological Institute, Aarhus C, Denmark
The use of the finite element method for understanding and analyzing the freezing and drying processes of food products is in focus in this paper. The objective of this study is to develop a model that can predict temperature distribution and weight loss of food products during the freezing and drying processes. The problem was solved by utilizing heat, mass transfer and moving mesh model. In ...
Eindhoven University of Technology, Eindhoven, The Netherlands
In this paper a new method for turbulent combustion modeling is introduced in COMSOL Multiphysics®. The method is called Flamelet Generated Manifolds (FGM). The method is based on the concept of flamelets, elemental reaction layers in combustion. The only hypothesis is that the turbulent combustion takes place in the Thin Reaction Zones regime (TRZ). A regime that normally is the case in gas ...
Rensselaer Polytechnic Institute, Troy, NY, USA
A model was developed to simulate the reaction, concentration field, flow field, and temperature distribution inside a Claus reactor for converting hydrogen sulfide to sulfur. The model considered two ideal reactors, a continuous stirred tank reactor and a plug flow reactor. As expected, two ideal reactors showed much different behaviors in terms of reactant conversion and operating ...
Diffusion and Reaction in Fe-Based Catalyst for Fischer-Tropsch Synthesis Using Micro Kinetic Rate Expressions - new
A. Nanduri, P. L. Mills
Department of Chemical & Natural Gas Engineering, Texas A&M University, Kingsville, TX, USA
Fischer-Tropsch synthesis (FTS) is a highly exothermic polymerization reaction of syngas (CO+H2) in the presence of Fe/Co/Ru-based catalysts to produce a wide range of paraffins, olefins and oxygenates, often known as syncrude. Multi-Tubular Fixed Bed Reactors (MTFBR) and Slurry Bubble Column Reactors (SBCR) are widely employed for FTS processes. The scale-up of MTFBR is complicated by the ...
K. M. Al-Shurman, H. Naseem
The Institute for Nanoscience & Engineering, University of Arkansas, Fayetteville, AR, USA
Chemical vapor deposition (CVD) is a promising effective method for synthesis of graphene films. CVD graphene film is obtained from hydrocarbon species such as CH4 through complex catalytic chemical reactions on the surface of the catalyst. Therefore, studying the catalytic reaction kinetics is essential process for understanding the thermal decomposition rate of methane on catalyst surface as ...
Modeling Heat and Moisture Transport During Hydration of Cement-Based Materials in Semi-Adiabatic Conditions - new
E. Hernandez-Bautista[1,2], D. Bentz, S. Sandoval-Torres, P. Cano-Barrita
National Institute of Standards and Technology, Gaithersburg, MD, USA
Instituto Politécnico Nacional/CIIDIR Unidad Oaxaca, Oaxaca, México
The process of accelerated curing of pre-cast concrete has a significant importance in the thermal behavior of concrete. A multiphysics model that describes hydration and heat and mass transport in cement based materials was developed. The hydration reactions are described by a maturity function that uses the equivalent time concept, thereby describing the change in the degree of hydration based ...
A. Nanduri , P. L. Mills ,
 Department of Chemical and Natural Gas Engineering, Texas A&M University - Kingsville, Kingsville, TX, USA
In the early 1920’s, Gas-To-Liquids (GTL) and Coal-To-Liquids (CTL) technologies were developed to account for the depleting crude oil resources . During this period, Franz Fischer and Hans Tropsch developed a process to convert synthesis gas (syn gas), derived from coal gasification, to a wide range of high value-added products. This process later came to be known as Fischer-Tropsch (F-T) ...
W. Beckert, M. Dannowski, L. Wagner, J. Adler
Fraunhofer IKTS, Dresden, Germany
The 3D unit cell model approach offers an efficient tool to analyze the influences of geometrical design (channel shape and arrangement, filter length, wall thickness) and filter material properties (permeability, soot loading characteristics) on the performance of ceramic particle filter structure in the soot loading process, assessed by pressure loss and soot loading capacity. It does ...
S.C. Seetharam, D. Jacques
Performance Assessments Unit, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium
This paper documents current status in the development of a coupled thermal-hydraulic-chemical-geomechanical numerical suite within COMSOL-MATLAB environment to address soil and concrete applications. The mathematical formulations are based on well-established continuum scale models unifying mass conservation, energy conservation, charge conservation, thermodynamic equilibrium and kinetics and ...
CFD Modeling and Analysis of a Planar Anode Supported Intermediate Temperature Solid Oxide Fuel Cell - new
N. Lemcoff, M. Tweedie
Rensselaer Polytechnic Institute Hartford, Hartford, CT, USA
Enthone, West Haven, CT, USA
A planar anode-supported intermediate temperature solid oxide fuel cell operating on syngas fuel at 750°C was analyzed in this study. The effects of varying syngas fuel inlet compositions on species and temperature distributions, water gas shift reaction rate, potential for carbon formation and electrochemistry were considered. A 2-D COMSOL® model was developed which included separate defined ...