J.R. Puentes, T.A. Osswald, S. Schick, J. Berg
Polymer Engineering Center, University of Wisconsin, Madison, WI, USA
TEEL Plastics, Baraboo, WI, USA
The extrusion of polyolefin pipes suffers degradation due to mechanical design problems of the extrusion die that is commonly used. This study uses numerical and computational approaches to detect problematic areas in the die geometry. Simulations show that in the conventional die there are areas of stagnation and recirculation of the melt flow, resulting in greater residence times, one of the ...
S. Sandoval Torres
Instituto Politécnico Nacional, CIIDIR, Oaxaca, Mexico
Drying of porous materials is characterized by the invasion of a gaseous phase replacing the evaporating liquid phase. Vacuum drying is an advanced method applied to oakwood to diminish discoloration, so understand its physics is a very important task. In this work, a two-scale model is solved to simulate vacuum drying of oakwood. A two scale model describes the physics of wood-water relations ...
Modelling and Simulation of Single Phase Fluid Flow and Heat Transfer in Packed Beds using COMSOL Multiphysics
S. Sachdev, S. Pareek, B. Mahadevan, A. Deshpande
Department of Chemical Engineering, BITS Pilani Goa Campus, Zuarinagar, Goa, India
Computational fluid dynamics has emerged as an advanced tool for studying detailed behavior of fluid flow and heat transfer characteristics in many chemical engineering applications like packed beds. Packed beds play an important role in various chemical industries. Hence understanding the fluid flow behavior and temperature variation in different sections of packed bed is essential. Geometric ...
M. Divakaran, S. K. Gupta
Department of Chemical Engineering, Indian Institute of Science, Bangalore, Karnataka, India
Due to the coupling of foam flow with foam generation step, the earlier studies on foam flow have not led to consistent results. An increase in flow rate to obtain ?P vs. Q data changes the foam under investigation itself. The controlled experiments carried out earlier in our group show that ?P increases with flow rate as Q^2/3, a weaker dependence than that known for laminar flow or plug flow ...
Numerical Study of the Controlled Droplet Breakup by Static Electric Fields inside a Microfluidic Flow-focusing Device
Y. Li, K. Nandakumar, M. Jain
Louisiana State Univeristy, Baton Rouge, LA, USA
Conventional passive microfluidic flow-focusing devices confront difficulties in controlling droplet sizes in dripping regime especially when the dispersed phase has a large viscosity. It is reported that external electric field can be used to manipulate the droplet breakup. In the present study, a computational fluid dynamics based level-set method coupled with perfect dielectric model has been ...
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 temperature. ...
D. Yuryev, M. Demkowicz 
Massachusetts Institute of Technology, Cambridge, MA, USA
We describe simulations performed in COMSOL Multiphysics® of the precipitation of helium (He) on solid-state interfaces. The non-uniform precipitation of He at certain interfaces is a result of a heterogeneous energy distribution in the interface plane: He wets high interface energy (“heliophilic”) regions but does not wet low interface energy (“heliophobic”) ones. Using a phase-field ...
S. Odiba, M. Olea, S. Hodgson, A. Adgar
Teesside University, School of Science and Engineering, Middlesbrough, United Kingdom
This research deals with the design of suitable microreactors for the catalytic oxidation of volatile organic compound (VOCs), using propane as a model molecule. The microreactor considered consists of eleven parallel channels, in which an Au/Cr/γ-Al2O3-catalyzed combustion reaction takes place. Each channel is 0.5 mm diameter and 100 mm long. The catalytic microreactor was simulated for ...
G. Zhang, S. Bearden
Clemson University, Clemson, SC, USA
It is necessary to understand and control nanopore behavior in order to develop biosensors for a variety of applications including DNA sequencing. The fluidics of nanopore devices we fabricated exhibits a range of interesting phenomena, such as enhanced conductance and current rectification. By electrically biasing nanopores, we were able to actively control the nanopore conductance in real time ...
K. J. Suthar, D. C. Mancini, M. K. Ghantasala
Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
Physical Sciences and Engineering, Argonne National Laboratory, Argonne, IL, USA
Department of Mechanical Engineering, Western Michigan University, Kalamazoo, MI, USA
The pH-sensitive hydrogels are responsive to the pH of surrounding solution, which often resemble to biomaterials. Recently, pH-sensitive hydrogels are widely used in various devices as sensing media. We present the simulation of swelling characteristic of 3D-arbitarary-geometry, pH-sensitive hydrogel in steady state conditions. Three nonlinear partial-differential equations that are ...