multiphysics modeling in femlab 3 tuesday, september 14th woods hole remi magnard
TRANSCRIPT
Multiphysics Modeling
in FEMLAB 3
Tuesday, September 14thWoods hole
Remi Magnard
• FEMLAB-overview
• Introduction to the FEMLAB modeling : diffusion-reaction in a zebra fish embryo
• Questions & Demo models on request from audience
Contents
What is FEMLAB used for?
• Structural mechanics
• Heat transfer• Acoustics• Electromagnetics• Fluid Flow• Chemical Engineering• Geophysics• General multiphysics and PDEs
Structure of FEMLAB
• FEMLAB core package– GUI, CAD tools, mesher, solvers, post-processing – Basic physics Modes– Arbitrarily-defined Equations
• Application Specific Modules– Electromagnetics Module
• Statics, eddy currents, microwaves, photonics,…– Structural Mechanics Module
• Solids (including thermal stresses, large deformations, elasto-plasticity, buckling), beams, plates, shells,…
– Chemical Engineering Module• Incompressible NS flow, compressible Euler flow,
chemical reactions,… • electrochemistry, porous media flows,…
Chemical Engineering
Module
Electromagnetics Module
Structural Mechanics Module
Heat Transfer Module
MEMS Module
Earth Science module
Equation implementation within FEMLAB
• Coefficient form:
• General form:
• Weak form:-ux_test*ux-y_test*uy+u_test
fauuuuct
uda
)(
Ft
uda
Diffusion-Reaction in a Zebra Fish Embryo
Introduction
• This model shows the modeling of diffusion-reaction processes in FEMLAB.
• The model shows the possibility of using different properties and different equations in different subdomains.
• The example is originally defined by Sander Kranebarg from the Wageningen University in the Netherlands.
Model Geometry
The geometry consists of three different subdomains:
–Main body
–Yolk
–Surrounding water.
Problem symmetric => only ½ of the geometry modeled
Problem Definition, diffusion
•Diffusion coefficient of the fish embryo : 5e-12
•Diffusion coefficient of the ambient water : 1e-12
•Reaction rate in the main body : -2.5e-4
Boundary condition :• fixed concentration on the exterior boundaries : c=16•Symmetry boundary conditions : 0 cn
Problem Definition, equation implementation
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uda
)(
Coefficient form :
da=alpha=gamma=beta=a=0c = diffusion coefficientf = reaction rate
Boundary condition:
rhu
hgquuuc T )(n
Result, Oxygen partial pressure
Conclusions
• The model is very simple to define and solve in FEMLAB.
• The results agree with the experiments and simulations done by Sander Kranenbarg at the Wageningen University.
• The model can be easily expanded to include effects of convection, which in the model are accounted for by an effective diffusivity.
• Straightforward equation implementation in the GUI
New features in FEMLAB 3.1 (released mid-October)
• Geometry – NURBS supported by IGES import – Live connection to SolidWorks
• Meshing – Support for Quad/Brick/Prism– Structured mesh
• Solvers – 64 bit FEMLAB server on several
platforms – Multigrid preconditioner – Electromagnetics preconditioner
based on multigrid • Structural Mechanics Module
– Piezo application mode – Incompressible materials – Heat-transfer shell
• Electromagnetics Module – Periodic boundary condition for
vector element – Far field postprocessing – 3D hybrid modes for waveguide – S-parameter postprocessing – Maxwell stresses postprocessing – Application mode with 2D quasi-
static formulation – Floating potential – Nonlinear magnetic materials
(example models)
• Chemical Engineering Module – 3D k-epsilon application mode – Divergence free elements
3 New modules!• Heat transfer Module:
– Conduction, convection and radiation modeling– Highly conductive layer boundary condition and heat transfer in shell– Bio-heat equation
• Earth-science module:– Porous media flow in variably saturate substrate– Poroelasticity model– Heat transfer in porous media
• MEMS module:– Piezoelectric material– Microfluidic and micromechanic application : micro-valve model, sensor.
Contact Information:
Jeanette LittmarckRegional Sales Manager
COMSOL, Inc781-273-3322
Visit www.comsol.com