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 ...
Sulfur Deactivation Effects on Catalytic Steam Reforming of Methane Produced by Biomass Gasification
P. Sadooghi, R. Rauch
Vienna University of Technology, Vienna, Austria
Sulfur, which is incorporated in the biomass structure, is released into the product gas during gasification as hydrogen sulfide. Hydrogen sulfide is known to deactivate nickel based steam reforming catalysts by chemisorption on the metal surface during steam reforming process. Desulfurization has a negative effect on the process efficiency therefore steam reforming has to be run without ...
The Effect of Electrolyte Flow Slots in Tooling Electrodes on Workpiece Surface Finish in Electrochemical Machining
Oregon State University, Corvallis, OR, USA
Electrochemical machining (ECM) uses electrolysis to precisely remove material at high rates. ECM has many advantages over conventional machining: no tool wear, no induced mechanical or thermal stresses, high removal rates virtually independent of material hardness or strength, and excellent surface finishes. However, challenges can arise during the design of the tooling electrode when ...
F. Alzahrani, F. Aiouache
Engineering Department, Lancaster University, Lancaster, UK
This work used the 3D CFD modeling to investigate non-uniform deactivation in packed bed reactors of low aspect ratios under steady state and dynamic operations. In order to explore the effects of condition of instability on local deactivation, detailed knowledge of flow dynamics (i.e. local structure of the packed bed, pressure drops and interstitial flow in the void space), heat and mass rate ...
S. Gunsekaran , R. C. Thiagarajan
ATOA Scientific Technologies Private Limited, Bangalore, India
Multiphysics Simulations of Physico-chemical and Biological Treatment of wastewater is increasing due to the demand for cost efficient plant design and utilization. Among the many processes, a thorough understanding of the settling behavior of an activated granular sludge in the secondary settler of an Effluent Treatment Plant (ETP) is critical for the plant designers to determine the efficiency ...
K. Cluff, L. Saeednia, H. Mehraein , R. Asmatulu
Department of Bioengineering, Wichita State University, Wichita, KS, USA
Department of Mechanical Engineering, Wichita State University, Wichita, KS, USA
Polymeric hydrogel is a promising class of drug delivery systems with the controlled release behavior in the body. In-situ forming hydrogels can be injected into the body as a fluid which forms a gel within the body tissue and improve the efficacy of the drugs. Various polymers have been used as in-situ hydrogel formulations. These polymeric formulations can form gels at body temperature while ...
C. Butcher, K. Yu
University of Maryland, College Park, MD, USA
The complex internal flow field of a hypersonic air-breathing propulsion engine was modeled using COMSOL Multiphysics® software. This type of flow field can be found in a dual-mode scramjet engine. After creating the geometry, a 2D CFD simulation was run using the High Mach Number Flow physics interface in the CFD Module. A stationary time study was run and the results from the CFD simulation ...
P. Patel, P. Vaidya, G. Singh
Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
Indian Oil Corporation Limited, Faridabad, Haryana, India
This paper presents a simulation approach to develop a model for understanding the mixing phenomenon in a stirred vessel. The mixing in the vessel is important for effective chemical reaction, heat transfer, mass transfer and phase homogeneity. In some cases, it is very difficult to obtain experimental information and it takes a long time to collect the data. Such problems can be solved using ...
D. Lahaye, L. Cheng
DIAM, EEMCS Faculty, TU Delft, The Netherlands
Tsinghua University, Beijing, China
In the production of high quality materials by a heat treatment, it is indispensable to accurately predict the temperature inside the furnaces being employed. In this work we develop a turbulent combustion model for the heat being released by gas burners inside a shaft kiln. Turbulent combustion is the strongly coupled phenomena of the chemically reacting fuel and oxygen in a turbulent flow. We ...
Institut für Automatisierungstechnik, Otto-von-Guericke Universität, Magdeburg, Germany
Preparative chromatography is an important separation method where the simulated moving bed (SMB) technology is an increasingly used separation process for binary mixtures. Several chromatographic columns are arranged in a ring where the feedings and drains are changed cyclically to maintain a continuous separation. For this reason, an adaptive controller is proposed to adjust the flow rates ...