G. Salazar Duarte, B. Schürer, C. Voss, D. Bathen
Linde AG, Munich, Germany
Universität Duisburg-Essen, Duisburg, Germany
Pressure Swing Adsorption (PSA) and Temperature Swing Adsorption (TSA) are commonly used for separation/purification of gas mixtures in industrial processes. The cycle time of industrial TSA processes usually ranges from several hours to days. The reason for this long cycle time is the usage of purge gas for heating and cooling the system (direct heating), which limits the application of TSA ...
G.M. Mule, A.A. Kulkarni
CSIR - National Chemical Laboratory, Pune, Maharashtra, India
Stirred tanks are widely used in the pharmaceuticals, chemical and paint industries for variety of operations. The fractal impeller is an impeller having a novel design, developed by CSIR-National Chemical Laboratory, Pune, India. The power number of fractal impeller is relatively lower than the conventional impellers. The mixing performance is also relatively better than the conventional ...
Bruno Chinè , Valerio Mussi , Michele Monno , Andrea Rossi ,
 School of Materials Science and Engineering, Costa Rica Institute of Technology, Cartago, Costa Rica
 Macchine Utensili e Sistemi di Produzione, Piacenza, Italy
 Dipartimento di Meccanica, Politecnico di Milano, Milano, Italy
Metal foams are interesting materials with many potential applications. Foamed metals or alloys include gas voids in the material structure and therefore the density is introduced as a new variable, with the real possibility to modify ad hoc their physical properties. In the indirect foaming process carried out in a furnace, simultaneous mass, momentum and energy transfer between three phases, ...
An Analysis of Heat Conduction with Change of Phase with Application to the Solidification of Copper
J. Michalski, and E. Gutirrez-Miravete
Rensselaer at Hartford, Hartford, Connecticut, US
The goal of this study was to determine the possibility of using the finite element in COMSOL Multiphysics program to obtain a high accuracy solution to a moving boundary problem, specifically, the solidification of copper. A one-dimensional geometry in Cartesian coordinates was used to investigate the solidification of initially liquid copper from a chilled wall maintained at fixed temperature. ...
S. Mahajani, S. Srikantiah, G. Samdani, A. Ganesh, P. Aghalayam
Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
Indian Institute of Technology Madras, Chennai, India
UCG is a process which converts coal to syn gas at the underground coal seam itself. UCG can help meeting the rising energy demand by utilizing coal resources that otherwise would be too deep, or of poor quality, or simply not economical to mine. As UCG takes place, a cavity is formed underground in the coal seam which grows three-dimensionally. The objective of this work is to develop a two ...
Department of Chemical Engineering, University of Arkansas, Fayetteville, AR, USA
During the hydraulic fracturing process, there can be possible re-activation of closed/sealed faults and natural fractures in the formation, which may lead to changes in the boundary conditions of the reservoir. While study models of shale gas formations have utilized the concept of a closed reservoir in order to optimize the production of gas in the well-bore, this assumption cannot be adopted ...
J. P. Wojeicchowski , A. P. Ramos , J. S. Sousa , L. G. Maciel , M. M. Pariona ,
 Universidade Estadual de Ponta Grossa, Ponta Grossa, PR, Brasil
 Universidad Peruana Unión, Juliaca, Peru
O objetivo deste trabalho foi modelar a perda de umidade de bananas Caturra com os modelos empíricos e com o software COMSOL Multiphysics, definindo os coeficientes convectivo de transferência de massa e difusivo. O valor obtido para coeficiente de difusão, com base no ajuste matemático da 2ª Lei de Fick para cilindros foi de 1,89.10-9 m²/s. O valor do coeficiente convectivo de transferência de ...
基于 Level-Set 界面跟踪方法建立了激光熔覆过程的三维瞬态数值模型，研究了瞬态熔化和凝固过程中传热传质的演化规律。该模型使用 Level-Set 方法跟踪熔池气/液界面，采用焓－多孔度（enthalpy-porosity）方法得到了固/液界面之间的糊状区，并考虑了质量添加、材料熔化/凝固、热毛细效应（Marangoni效应）、浮力效应、活性元素质量传输等对熔池流动和界面的影响。通过该模型，具体分析了质量添加、力和界面平衡条件对熔池气/液界面的影响，以及由熔池温度/浓度分布引起的热毛细效应、金属材料的熔/凝过程和熔池流动形式对熔池固/液界面的影响。结果表明：熔池的气/液界面主要由力平衡条件决定，截面近似为圆弧型，其尺寸与单位时间的质量添加量相关。熔池的固/液形态由于熔池的表面温度梯度和表面活性元素含量共同引起的熔池流动方向和速度的变化，出现三种不同的类型，分别为下凹型（熔池内流） ...
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 ...
M. M. Pariona , F. de Oliveira ,
 State University of Ponta Grossa, PR, Brazil
INTRODUCTION The purpose of this work is to verify the effect of Multigrid method on the CPU time for the resolution of the heat transfer model, based on the Finite Element Method (FEM), in order to simulate the laser surface remelting (LSR) of the Al–1.5 wt.% Fe alloy. To accelerate the convergence of Single grid methods, Multigrid method (MG) was employed in order to reduce the CPU time. In ...