H. Cremasco, K. Angilelli, D. Borsato
Universidade Estadual de Londrina, Londrina, Paraná, Brazil
The transfer of sucrose and fructooligosaccharides to melon and water to solution was modeled based on generalized form of Fick’s second law for simultaneous diffusion and resolved by the finite element method using the software package COMSOL Multiphysics® software. The diffusion coefficients, the mass transfer coefficient and the Biot number were determined using the simplex optimization ...
M. Gobbert, and S. Yang
Department of Mathematics and Statistics, University of Maryland, Baltimore, MD, USA
The convergence order of finite elements is related to the polynomial order of the basis functions used on each element, with higher order polynomials yielding better convergence orders. However, two issues can prevent this convergence order from being achieved: the lack of regularity of the PDE solution and the poor approximation of curved boundaries by polygonal meshes. We show studies for ...
G. Hulkó, C. Belavý, P. Bucek, K. Ondrejkovic, and P. Zajícek
Institute of Automation, Measurement and Applied Informatics of Slovak University of Technology, Bratislava, Slovak Republic
In systems and control theory dynamical systems described by partial differential equations are known as distributed parameter systems. So for modeling and dynamical analysis of distributed parameter systems wide possibilities are offered by COMSOL Multiphysics® based on numerical solution of sets of partial differential equations by finite element method. Paper presents actual possibilities ...
Z. Aljobeh, G. Argueta
Valparaiso University, Valparaiso, IN, USA
A numerical model was developed to make spatial and temporal predictions of the water quality for Brewster Lake, located in southwestern Michigan. The model considers the hydrodynamics of the lake, hydrologic conditions, physical, chemical and biochemical processes that take place in the lake, and nutrient loadings from the surrounding watershed. Physical, chemical, and biochemical data ...
I. Neitzel, U. Prüfert, and T. Slawig
DFG priority program SPP 1253, Technische Universität Berlin, Berlin, Germany
DFG research center Matheon, Technische Universität Berlin, Germany
DFG Cluster of Excellence The Future Ocean, DFG priority progam SPP 1253, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
We use COMSOL Multiphysics to solve time-dependent optimal control problems for partial differential equations whose optimality conditions can be formulated as a PDE. For a class of linear-quadratic model problems we summarize known analytic results on existence of solutions and first order optimality conditions that exhibit the typical feature of time-dependent control problems, namely the fact ...
P. Schmitz, A. Cockx, S. Geoffroy, and J. Gunther
Biochemical Engineering Dpt., Université de Toulouse, Toulouse, France
Chemical Engineering Dpt., Université de Toulouse, Toulouse, France
Mechanical Engineering Dpt., Université de Toulouse, Toulouse, France
An undergraduate course is developed to initiate future engineers to multiphysics numerical simulation by approaching concrete cases in various fields such as: heat transfers, fluid flow, mechanics, chemistry and electrostatics. The so called “Virtual Experiments” course consists of four projects given successively to students. Each project lasts about ten hours. The major notions related to ...
X. Ma, M.B. de Rooij, and D.J. Schipper
Materials Innovation Institute, Enschede, The Netherlands
University of Twente, Enschede, The Netherlands
This paper describes the use of COMSOL Multiphysics® to determine the shear layer thickness in thin–section aluminum extrusion, based on the minimum work criterion. The studied two aluminum alloys are AA 6063 and AA 7020. The results show that a continuous shear layer featuring shear localization due to localized thermal softening is not possible to form under typical thin&ndash ...
T.C. Zhu, and X. Liang
University of Pennsylvania, Philadelphia, PA, USA
Singlet oxygen (1O2) is the major cytotoxic agent in photodynamic therapy (PDT). The reaction between 1O2 and tumor cells defines the treatment efficacy. Based on a previously developed model that incorporates the diffusion equation for the light transport in tissue and the macroscopic kinetic equations for the generation of the singlet oxygen, the distance-dependent reacted 1O2 is numerically ...
Reliable Full-Wave EM Simulation of a Single-Layer SIW Interconnect with Transitions to Microstrip Lines - new
J. L. Chavez-Hurtado, J. E. Rayas-Sanchez, Z. Brito-Brito
ITESO - Universidad Jesuita de Guadalajara, Tlaquepaque, Jalisco, Mexico
We present a procedure to obtain reliable EM responses for a SIW interconnect with microstrip line transitions. The procedure focuses on two COMSOL® configuration settings: meshing size and simulation bounding box. Once both are properly configured, the implemented structure is tested by perturbing the simulation bounding box to ensure it has no effect on the EM responses.
Solving Distributed Optimal Control Problems for the Unsteady Burgers Equation in COMSOL Multiphysics®
F. Yilmaz and B. Karasözen
Department of Mathematics, Gazi University, Ankara, Turkey
Department of Mathematics and Institute of Applied Mathematics, Middle East Technical University, Ankara, Turkey
We use COMSOL Multiphysics® for solving distributed optimal control of un- steady Burgers equation without constraints and with pointwise control constraints. Using the first order optimality conditions, we apply projection and semi-smooth Newton methods for solving the optimality system. We have applied the standard approach by integrating the state equation forward in time and the ad- joint ...