News in COMSOL Multiphysics 3.2

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News in COMSOL Multiphysics 3.2
Prague 2005-11-15 Bertil Waldén COMSOL AB
Place
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FEMLAB is now COMSOL MultiphysicsTM

• First name was PDE Toolbox
• Because it solved PDEs
• Second name was FEMLAB
• Because it made use of the Finite Element Method
• Now we are dealing with Multiphysics and want a
  name that expresses this
• Name structure same product and company name
• Not all future products will be FEM or FEA based

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COMSOL Products
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New Products

• COMSOL ScriptTM
• CAD Import Module
• Add-ons to the CAD Import Module
• Pro/E Import Module
• CATIA V4 Import Module
• CATIA V5 Import Module
• Inventor Import Module
• VDA-FS Import Module

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COMSOL ScriptTM
Command-line modeling, technical computing,
visualization and GUI-design
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Programming language and fast graphics

• COMSOL Script
• Fully compatible with the MATLAB language
• All data types except objects
• Command line debugger, dbstop, dbstep, dbcont,
  ...
• Java interface
• Fast 3D graphics using OpenGL acceleration (50
  times faster than Matlab)

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Batch execution with COMSOL Script

• Requested feature that allow several simulations
  to run sequentially or simultaneously
• The simulation can be distributed over a network
  to run on different machines
• COMSOL Script executes an M-file that defines the
  simulation

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Main news in COMSOL Multiphysics 3.2
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Support for units

• Metric units
• SI units
• CGS units
• MPa units suitable
• for structural analys
• EM units
• ES units
• English units
• British engineeringunits
• FPS
• IPS
• Gravitational IPS
• No units

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Pre-defined multiphysics couplings
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Grouping of subdomains and boundaries
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More improvements

• Customized report

Select the content of your report

• For constants and expressions
• save and open
• add descriptive comments

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New material library functionality

• Support for anisotropic materials and orthotropic
  materials
• Both the 6-by-6 elasticity matrix in 3D and the
  4-by-4 elasticity matrix in 2D are supported.
• Support for piezoelectric materials
• The piezoelectric matrices elasticity matrix,
  coupling matrix and permittivity matrix are
  supported.
• Support for elastic-plastic and hyperelastic
  materials
• Material functions can be specified
• For example temperature dependent material
  properties

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Performance Improvements

• Further develop the solvers to solve MUCH larger
  problems MUCH MUCH faster
• Built-in support for wave equations (DOFs reduced
  with 50, iterative solvers more efficient)
• 5-10 times larger CFD problems solved with new
  multigrid smoother (Vanka) for laminar flow
  (tested), turbulent flow (tested), arbitrary
  multiphysics problems (not tested)
• A bunch of under-the-hood improvements on mesh
  stability, incomplete LU preconditioner, file
  storage of solutions (during transient solving)

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Wave Equations in 3.1 and 3.2

• 3.1 Substitution
• Unsymmetric Jacobian matrix with zeros on the
  diagonal
• Not good for iterative solvers
• Memory waste
• Two dofs to keep track of
• 3.2 New formulation
• One variable, symmetric Jacobian if the PDE is
• Very good for iterative solvers!
• Memory efficient!

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Transient analysis improvements

• Time derivatives can be used freely in
  expressions
• Logical names ut, utt, uxt, uxtt
• Reduces the number of degrees of freedom in your
  models.
• Memory and solution times significantly improved.
• Store solution on file.

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New ODE Interface

• Type in ODE as it is ut-u0
• Creates a global DOF
• Easier to use than Weak Form, Point

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New CFD Benchmark Turek's

• Laminar flow, 3D
• On 32-bit architecture, 2GB RAM 450 kdofs,
  60-90 minutes
• In 3.1, 240 kdofs, 4-5 hours
• On 64-bit architecture, 12 GB RAM 2150 kdofs,
  6-8 hours
• In 3.1, 400-500 kdofs, 16 hours

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Exciting new feature Moving boundaries and mesh
with the ALE-method
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Moving meshes with ALE

• ALE is a technique used to handle single physics
  or multiphysics problems where the effect of the
  deformation on the physics cannot be neglected.
• A simple example of this is the 2D fluid
  structure interaction model

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Moving meshes with ALE
Original mesh
Deformed mesh

• ALE smooths out the mesh deformations in the
  entire domain in a diffusive manner
• Analogy Think of the mesh element edges as
  interconnected springs which are compressed or
  extended due to prescribed deformations on the
  boundary or in the subdomain

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Implementation and use

• The deformed mesh (ALE) is now baked into an
  application mode of its own

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Implementation and use

• Two coordinate systems reference frame (Geom1)
  and deformed frame (Frame(ale))
• The structural application mode usually drives
  the deformation --include this in the reference
  frame.
• Include forces driving structural deformations
  (for example pressure from fluid) in the moving
  frame

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Sloshing tank
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Peristaltic pump
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ALE method - limitations

• Does not handle topology changes

OK
Not OK
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Example Parameterized geomety (ALE)
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Objective

• To make it possible to automate modification of
  geometry without resorting to command line
• The changes made to the geometry can be for
  example translation or scaling of a given
  geometry object

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Simple example of Parameterized Geometry
Distributed heat source
All boundares kept at T288 K
Moving drilled hole (mesh deformation)
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Results, temp
Deformed mesh
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New in COMSOL 3.2 Customized GUIs

• Catch parts of COMSOL Multiphysics in your own
  easy-to-use windows.
• Create a GUI of your own that can run all types
  of scripts COMSOL Multiphysics or user-defined.
• Uniqe function customized GUIs work with all
  types user functions for all types of analysis!

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How to do?

• Two simple steps
• Create a Java component through a simple script
• Run your own script functions through a GUI event
  (push a button)

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Why customized GUIs?

• Perfect for teaching.
• Allow the user to generate simplified GUI for
  customized problem.
• Non specialist engineer can do a finite element
  analysis.
• Consultancy company that can provide a study to
  their own customer.
• Design engineer that are not specialized in FE
  analysis for quick and common optimization of
  designed.

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Components

• Each frame can be split in different panel.
• Dont need to define the size of each panel as
  they are automatically scaled on a grid

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The m-files
geommodel.m (creates the geometry) function
geommodel(event) widthframe.get('width').getValue
heightframe.get('height').getValue centerxfra
me.get('centerx').getValue centeryframe.get('cen
tery').getValue radiusframe.get('radius').getVal
ue g1rect2(width,height,'pos','0','0') g2cir
c2(radius,'pos',centerx,centery) s.objsg1,g2
fem.drawstruct('s',s) fem.geomgeomcsg(fem) g
eomplot(fem)

• minigui.m (sets up the GUI)
• f1frame('FEMLAB','size',800 600)
• p1panel
• p1.add(label('Rectangle width'),1,1)
• p1.add(label('Rectangle height'),2,1)
• p1.add(label('Circle center x'),3,1)
• etc.
• p2panel
• p2.add(label('Element size'),1,1)
• etc.
• f1.get('geombutton').addActionListener('geommodel'
  )
• f1.get('meshbutton').addActionListener('meshmodel'
  )
• f1.get('solvebutton').addActionListener('solvemode
  l')
• f1.get('plotbutton').addActionListener('plotmodel'
  )

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Quick preview COMSOL Reaction Engineering LAB
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What is the Reaction Engineering Lab?
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3 cornerstones of Reaction Engineering

• Reaction kinetics
• Evaluate it quickly
• Physical properties of reacting systems
• Be accurate
• Modeling coupled phenomena
• Stay organized

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Setting up reaction kinetics
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Physical properties of reacting systems