comsol_ workshop.pdf

8/14/2019 COMSOL_ workshop.pdf

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Advanced COMSOL Multiphysics - WSU

2012COMSOL.COMSOLandCOMSOLMultiphysicsare registeredtrademarks ofCOMSOLAB. CapturetheConcept,COMSOLDesktop,andLiveLink aretrademarks ofCOMSOLAB. Otherproductor brandnamesaretrademarks or registeredtrademarksoftheirrespectiveholders.

John Dunec, Ph.D.

COMSOL, Inc.

Agenda Morning Intro

IntroductionWorked Example: Joule Heating

Warmup: 3 Quick Problems Hot Rod Cap ac itor Wrench

Multiphysics Problems: Thermal Decomposition H-Cell Microfluidics Natural Convection in a Light Bulb

Agenda Afternoon Advanced

Worked Example: Magnetophoresis

Meshing Infinity Infinite Elements Perfectly Matched Layers

Meshing and Mesh Control Basic Mesh Control Interactive Mesh Control Swept Meshing ALE Moving Mesh

Postprocessing: The Results Node

MagneticField

Flow Profile &Particle Pathlines

Multiphysics: Multiple Interacting Phenomena

Could be simple: Heat convected by Flow

Could be complex: Local temperature sets

reaction rates Multiple exothermic

reactions Convected by flow in pipes

and porous media Viscosity strongly

temperature dependent

COMSOL Multiphysics Solves These!

Multiphysics Everything can link to everything.

Flexible You can model just about anything.

Usable You can keep your sanity doing it.

Extensible If its not specifically thereadd it!

Trusted by 80,000+ Users Worldwide

Product Suite

AutoCAD andInventor areregisteredtrademarksofAutodesk, Inc. LiveLink forAutoCAD andLiveLink forInventor arenot affiliatedwith, endorsedby, sponsoredby, or supportedbyAutodesk, Inc. and/oranyof itsaffiliatesand/or subsidiaries. CATIA isaregisteredtrademarkof Dassault SystmesS.A. oritsaffiliatesor subsidiaries. SolidWorks

isa registeredtrademarkofDassault SystmesSolidWorksCorporationorits parent, affiliates, orsubsidiaries. Creo isatrademarkand Pro/ENGINEER isa registeredtrademarkofParametric TechnologyCorporationor itssubsidiariesin theU.S and/orin othercountries. MATLAB isa registeredtrademarkofThe MathWorks, Inc.


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Anywhere you can type a number you can type an equation

Or an interpolation function And it can depend on anything known in your problem

Example: Concentration-dependant viscosity:

221001.0 c

Low concentration,High velocity

High concentration,Low velocity

Add Your Own Equations to COMSOLs

Dont see what you need?

Add your own equation ODEs PDEs Weak form PDEs

Just type them in No Recompil ing No Programming

Capture the Concept TM

MagnetophoresisMagnetophoresis

Blood Cell Separation with Magnetophoresis

Key Elements Simulating a magnetic field from

a permanent magnet

Disturbing the B-field to producemagnetic gradients

Simulating flow in a microfluidicslab-on-a-chip set of flow channels

Using Particle Tracing toconcentrate blood cells respondingto magnetophoretic forces

Reference & Key Separation Property

Model Based on Paper Presented at 2009 COMSOL Conference:

G. Schiavone, D. Kavanagh, & M. Desmulliez, Design and Simulation ofa Microscale Magnetophoretic Device for the Separation of Nucleated

Fetal Red Blood Cells from Maternal Blood, Proceedings of the COMSOLConference 2009 Milan

Key Material Property: The magnetic susceptibility c of red blood cells depends on the oxidation

state of the hemoglobin molecules. RBCs in a normal state exhibit anextremely weak diamagnetic behaviour as c is negative and quite close tozero.

c = -3.9e-6 Therefore permeability = (1 3.9e-6)

3 Physics: Magnetics, Flow, & Particle Tracing

Magnetics Fluid Flow Particle Tracing

Particles respond to both Drag and Magnetophoretic Forces


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COMSOL Products Used This Tutorial

AutoCAD andInventor areregisteredtrademarksofAutodesk, Inc. LiveLink forAutoCAD andLiveLink forInventor arenotaffiliated with, endorsedby, sponsoredby, or supportedbyAutodesk, Inc. and/oranyof itsaffiliatesand/or subsidiaries. CATIA isaregisteredtrademarkof Dassault SystmesS.A. oritsaffiliates orsubsidiaries. SolidWorks

isa registeredtrademarkofDassault SystmesSolidWorksCorporationorits parent, affiliates, orsubsidiaries. Creois atrademarkand Pro/ENGINEER isa registeredtrademarkofParametric TechnologyCorporationor itssubsidiariesin theU.S and/orin othercountries. MATLAB isaregisteredtrademarkofT heMathWorks, Inc.

COMSOL Multiphysics, AC/DC Module, Microfluidics Module Along with the Particle Tracing Module

Tutorial Roadmap

First: Setup and Solve Magnetics & Flow

Choose two physics Import geometry sequence Define materials (Glass, Soft Iron, Water) Set up Permanent Magnet Set Flow Boundary Conditions Mesh Solve

Finally: Add Particle TracingMagnetic Field

Surrounding NeodymiumMagnets

Geometry

Glass Substrate

Two NeodymiumPermanent Magnets

Microfluidics FlowChannel with 3 Outlets

Passive Array of SoftIron Patches(Creates Field

Concentrators)

Array of Soft Iron Patches

Magnet

Flow Channel

Magnet

Magnetic Equations

Solve Magnetics based on the Scalar Magnetic Potential, V m

Amperes Law relates H and B

In Permanent Magnets H related to B through Magnetism M

0B

HmV

HBr 0

MHB 0

Lets do this in COMSOL


Step-by-stepFlow & Magnetics

Step-by-stepFlow & Magnetics


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Create a Material: NeodymiumMagnet

Rt Click on Materials

Choose Material

Name Material Rt Click on Material 4 Rename to NeodymiumMagnet

Set Material Properties Select the two magnet domains Set mur as 1.05

Magnetize the Permanent Magnet

Rt Click on Magnetic Fields, No Currents

Choose Magnetic Flux Conservation(This adds a 2 nd Mag Flux Conserv. Node)

Select both Neodymium Magnet domains

Locate the Magnetic Field section change Relative permeability to

Magnetization

Enter y component of M as 5.97e5

Avoid Field Distortion by Outer Boundary

Add Infinite Element Geometry Expand Geometry 1 Highlight Circle 1 Overall Expand Layers Section Enter Layer Thickness as 0.005 Bu ild all

Add Infinite Element Domains Rt Click on Definitions Choose Infinite Element Domains Select the new outer layers

Change the Type to Cylindrical

Magnetic Potential Needs One Known Point

Set the magnetic value somewhere:

Rt Click on Magnetic Fields, No Currents Choose Points > Zero Magnetic Scalar

Potential

Select the Leftmost Point to right of infiniteelement domains

Flow Boundary Conditions: Inlet

Rt Click on Creeping Flow Choose Inlet

Select the leftmost vertical flowboundary

Change Boundary Conditionto Velocity

Enter Velocity as 0.5e-3

Flow Boundary Conditions: Outlet

Rt Click on Creeping Flow Choose Outlet

Select the three right-mostvertical flow boundaries

Leave Boundary Conditionas Pressure,

Leave Pressure as 0


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Set Channel Depth

Highlight Creeping Flow

Change Compressibility toIncompressible flow

Select Use shallow channelapproximation

Enter d z as 50e-6

Mesh the Infinite Element Domain

RtClick on Mesh 1

Choose Mapped Select the 4 Infinite Element domains

Rt Click on Mapped 1 Choose Distribution Select the top vertical boundary Number of Elements: 3

Rt Click on Mapped 1 Choose Distribution Select the outer circle boundaries Number of Elements: 15

Mesh the Inlet Flow Channel

RtClick on Mesh 1 Choose Mapped Select the inlet flow domain

Rt Click on Mapped 2 Choose Distribution Select right vertical boundary Number of Elements: 10

Rt Click on Mapped 2 Choose Distribution

Select top inlet channel boundary Number of Elements: 1500

Mesh the Small Flow Rectangle

RtClick on Mesh 1 Choose Mapped Select the small flow domain

Rt Click on Mapped 3 Choose Distribution Select top rectangle boundary Number of Elements: 10

Buil d All

Mesh the Outlet Channels

RtClick on Mesh 1 Choose Mapped Select the 3 outlet flow domains

Bu ild All

Distribution Upper Outlet

Rt Click on Mapped 4 Choose Distribution Select BOTH the long upper outlet

boundaries

Change to Predefined distribution Number of Elements: 70 Element Ratio: 10

Distribution method: Arithmetic seq

Buil d All


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Distribution Lower Outlet

Rt Click on Mapped 4

Choose Distribution Select BOTH the long lower outletboundaries



Choose Reverse direction Bu ild All

Distribution Middle Outlet

Rt Click on Mapped 4

Choose Distribution Select BOTH the long middle outletboundaries



Choose Reverse direction Buil d All

Mesh the Remaining Glass

RtClick on Mesh 1 Choose Free Triangular Leave as Remaining

Rt Click on Free Triangular 1 Choose Size

Select ONLY the Glass Domain Calibrate for General Physics Set Size as Extra Coarse

Bu ild All

Set up Two-Step Study

Rt Click on Study 1 Choose Study Steps Choose Stationary

Highlight Step 1: Stationary Deselect Calculating Flow

Highlight Step 2: Stationary 2 Deselect Calculating Magnetics

Rt Click on Study 1 Rename to Study 1 Flow and Magnetic Field

Solve for Flow and Magnetic Field

Rt Click on Study 1 Hit Co mp ute

Magnetic Field

Magnetic Field

Flow Velocity

Solution Should be Done

164,000 Degrees of Freedom

37 seconds on my desktop


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Add Arrows for Magnetic Flux

Expand Results

Rt Click on Magnetic Flux Density Choose Arrow Surface

Plot Magnetic Flux Density X-points: 25 Y-points: 20 Scale Factor: 0.006

Color: Cyan


Forces on ParticlesForces on Particles

Next Add Particle Tracing for Blood Cells

Add 2 nd Physics: Particle Tracing, Transient

Define Particle Physics Define the Particle Properties Add the Drag Force, Link to velocity field Add the Magnetophoretic Force, Link to B field Create an Inlet (100 cells, velocity = V_inlet)

Set up Transient Study Time Stepping Link Transient Particle Tracing to Previous Study

Forces on the Blood Cells

Newtons Law recast to change in momentum

The magnetophoretic force is based on the gradient magnetic field

The fluid dynamic drag will be that predicted by Stokes law:

vaFFF mdt d

m D M

2,0

32 HF K r f r p M

p p p p D md vuF 218

Particle Properties

Density: 2200[kg/m 3] Diameter: 6e-6[m] Charge Number: 0 Permeability: (1 3.9e-6)

Red Blood Cells are somewhat donut shaped with a majordiameter of about 9 microns and a thickness of about 3 microns.

An equivalent sphere is roughly 6 microns in diameter.

Lets do this in COMSOL


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Step-by-stepParticle TracingStep-by-step

Particle Tracing

Add Particle Tracing

Rt click on Model 1

Choose Add Physics

Choose Fluid Flow >Particle Tracing for Fluid Flow

Choose the blue Next arrow Choose Time Dependant Deselect Solve For the other physics Pick Finish Flag

Note: You need an additional study since particle tracing is transientwhereas the magnetic analysis was stationary.

Create Flow Channel Selection

Expand Materials Highlight Water, Liquid

Choose the Create Selectionbutton

Name the Selection:Flow Channels

Particles only in Fluid Domains

Highlight Particle Tracing for Fluid Flow

Go to Domain section Pick Clear Selection button (the broom)

Choose Flow Channels domains in theselection list

Walls Change to Bounce

Under Particle Tracing for FluidFlow

Highlight Wall 1

Change Wall Condition toBounce

Cells bounce back into main flow

Set Particle Properties

Under Particle Tracing for Fluid Flow Highlight Particle Properties 1 Set to Specify particle density and

diameter

Enter Values: Particle density: 2200[kg/m 3] Particle diameter: 6e-6[m] Charge Number: 0

Red Blood Cells are somewhat donut shaped with a majordiameter of about 9 microns and a thickness of about 3 microns.

This is an equivalent sphere.


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Add Fluid Drag Forces

Rt Click on Particle Tracing for Fluid Flow

Choose Drag Force

In Domain Selection section, chooseFlow Channels

In the Drag Force section, change velocityfield entry, u , to Velocity field (spf/fp1)

Add Magnetophoretic Forces

Rt Click on Particle Tracing for Fluid Flow

Choose Magnetophoretic Force

In Domain Selection section, choose FlowChannels

In the Magnetophoretic Force section, changeMagnetic field, H, to Magnetic field (spf/fp1)

Enter values: Particle relative permeability: 1-3.9e-6

(-3.9e-6 is the susceptibility) Fluid relative permeability: 1

Boundary Cond: Particle Inlet

Rt Click on Particle Tracing for Fluid Flow Choose Inlet

Select the left-most vertical flow boundary

Change Initial position to Uniform Set N to 100 Set Velocity field to Velocity field (spf/fp1)

Boundary Cond: Particle Outlets

Rt Click on Particle Tracing for Fluid Flow Choose Outlet

Select the 3 right-most vertical flow boundaries

Leave Wall Condition as Freeze

Assign Stationary Solver to Flow & Magnetics

Expand Study 1

Note: Both of the following are likely to

have been done for you already

Hig hl ig ht Step 1: Stationary In the Physics Selection : Deselect Charged Particle Tracing

Hig hl ig ht Step 2: Stationary 2 In the Physics Selection : Deselect Charged Particle Tracing

Assign Transient Solver to Particle Tracing

Expand Study 2 Highlight Step 1: Time Dependant In the Physics Selection: Mak e sure Magnetic Fields is deactivated Mak e sure Creeping Flow is deactivated

Rename Study RtClick on Study 2 Choose Rename Change name to Study 2 Blood Cells


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Use Magnetics & Flow Solution from Study 1

Under Step 1: Time Dependant

Ex pand th e Values of DependentVariables section

Select Values of variables not solve for Method: Solution Stud y: Study 1, Stationary Stationary: Automatic

Set Times and Solve

Highlight Step 1: Time Dependant

Cho ose the Range button Leave entry method as Step Start: 0 Step: 0.1 Stop: 60 Pick Replace

RtClick on Study 2> Hit Compute(Takes about 27 seconds)

Plot Particles as 3x Actual Size

Expand Particle Trajectories (cpt) Highlight Particle Trajectories 1

Leave Type as Point Change Radius expression to 6e-6 Select Radius Scale Factor Enter Radius Scale Factor as 3

Plot Zoom in on Y-Transition

Add Lines to Trajectories

Highlight Particle Trajectories 1

Change Type to Line Plot

Add Arrow Plot

Expand Results Rt Click on Particle Trajectories (fpt) Choose Arrow Surface

Plot Flow Velocity (u, v)

Change x-Method to Coordinates Set x coord to 0.0104

Change y-Method to Coordinates Range: -0.0006 to 0.0006 in 65 steps Scale Factor: 1

Compare with NO Magnetophoretic Force

Expand Particle Tracing For Fluid Flow Rt Click on Magnetophoretic Force Choose Disable

Rt Click on Study 2 Hit Co mp ute

WITHOUTMagnetophoretic Force

WithMagnetophoretic Force


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PMLs & InfiniteElements

PMLs & InfiniteElements

You cannot model everything

You can never model the

entire universe

Boundary conditionsrepresent the outside

Two types: physical walls andartificial boundaries

Use artificial boundaries tomodel only the region ofinterest

Model

Everything else

BC

BC

BC BC

Something else

Infinite Elements Currently in AC/DC, Soon Throughout

Draw Rectangle, 2 Large Circles

Subdomain > Make Circles Not Active

Rectangle Boundaries ZeroCharge

Left Circle: V = 5 Right Circle V = -5

Solve; Contour Plot > 30 Contours

Geom Add Outer Inf Elem Geom

Subdomain Inf Elem Tab Match Matls

Inf Elems >Cartesian, Stretch in Proper Dir Solve Hide Inf Element Subdomains

Perfectly Matched Layers Absorbing Subdomain Absorbs incident waves without reflection Artificial boundary for non-enclosed spaces Used instead of radiation boundary condition Make thickness at least one wavelength

PMLQuick Example

Circle 1: R= 8 Center: (0,2) Circle 2: R= 4 Center: (0,0) f =100 Hz c =343 m/sec (air) L=c/ f = 3.4 Mesh Size = 3.4/5 Inner Circle Acceleration BC, a0=1 Add PML Circle 3: R=12 Center: (0,2)

Sound Hard Wall Radiation - Cylindrical PML - C ylindrical

Make PML at least one wavelength thick


FEA MeshDescretization

FEA MeshDescretization


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When to use linear elements?

COMSOL uses linear elements by default for: Fluid flow Plasmas Contact pressure in Solid mechanics Temperature in Thermal stress

If you already have a very fine mesh due to geometric complexity

Very large models where you can only get low accuracy

Transient problems Magnetic field with nonlinear material

2nd or 3 rd order elementscapture curvature inside

elements

Linearelements

no curvature

When To Use Higher Order Elements

Use for quick Accuracy Improvement Watch Out Though! Can produce large (erroneous) numerical overshoots Can make model size very large

Use higher order elements when calculating higher order derivatives Field represented by 2 nd order Shape Functions in Element 1 st Spatial Derivative Linear Function in Element 2 nd Spatial Derivative Constant in Element 3 rd Spatial Derivative ZERO! 4 th Spatial Derivative ZERO!

Linearelements

no curvature

How to Change Element Order

Buttons at Top of Model Builder: Turn On Visibility of Discretization

Highlight Individual Physics Nodes Expand Discretization Change order of elements

Sometimes, the geometry should beadjusted to improve the model

1. Geometric Singularities

2. Fille ts

3. Thin Regions & High Aspect Ratios

4. Glancing Contact

5 . Sliver Faces

6. Too Much Detail

7 . Symmetry

8. Infinitely extended region

1. Geometric Singularities

Plate in tension with a sharp notch

The stresses at the notch will beinfinite, although the displacements

will be correct

Adding a small, physically realistic fillet,will remove the singularity, but it will

increase the number of elements

2. Fillets

Overly detailed geometry Sharp corner = singularityCompromise between lowerelement count & accuracy


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3. Thin regions

t < L/100 Thin domains can often be representedvia boundary conditions that do not

require a volumetric mesh

3. High Aspect Ratios

L >> d t 1,000:1 require extreme care

Aspect ratios > 1,000,000:1 may require a different approach

4. Glancing contact

Instead, try:

Small Gap

Small Overlap

Perform convergence studyon gap/overlap size

5. Sliver faces

Small elements and high aspectratio elements are present

This usually requires re-drawing the CAD geometry

6. Too much detail

Remove as many of the small features as reasonable

Consider using VirtualOperations on geometry

7. Use symmetry

Use symmetry planes

Model on reduced geometry

- Les s mes h

- Less memory- Les s t ime

Consider using:

- 2D if there is no variation ingeometry and solution out-of-plane

- 2D axisymmetry if there is novariation in geometry and solutionabout an axis of revolution


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8. Infinitely Extended RegionInfinite Elements

Currently available for:- Electrostatics and Magnetostatics

- Heat transfer - D if fu si on- Structural Mechanics

Models an infinitely extendedregion for time-invariant problems

Perfectly Matched Layer Applicable to wave-type models:

Elastic waves in structures

Pressure waves in fluids (acoustics) EM waves (RF)

Models an infinitely extendedregion where the waves areabsorbed without reflection


Meshing &Mesh ControlMeshing &

Mesh Control

Simple Mesh Control Here 2D

Draw the Following Shapes

Explore Custom Parameters under Size Node

Predefined mesh options

9 options from Extremely Coarse to Extremely Fine

Custom mesh: Element Size Parameters

Maximum element size

Minimum element size

Maximum element growth rate

Resolution of curvature

Resolution of narrow regions

Maximum element size This sets the maximum length of the edge of any element Needs to be a positive number If you do not pick a value, COMSOL uses L/10, where L is the maximum

dimension of the model


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Minimum element size This sets the minimum length of the edge of any element Needs to be a positive number

Useful to ensure that too many elements are not generated aroundsmall curved parts

Maximum element growth rate

Rate at which the element size can grow from a region with smallelements to a region with larger elements

Needs to be a number between 1 and 2

Resolution of curvature Determines the size of boundary elements compared to the curvature of

the geometric boundary Max element size along boundary = curvature radius x resolution of

curvature Needs to be a positive number Smaller value gives finer mesh

Radius

Resolution of narrow regions Control the number of layers of elements that are created in

narrow regions A value between 0 to 1 produces anisotropic element

Needs to be a positive number

Resolution = 1

Resolution = 3

Interactive Meshing Piston Head Boundary Layer Meshing

Best for things that have boundary layerdetails

New > 3D Geometry > Finish

Right Click on Geometry > Cylinder > Build Right Click on Mesh > Boundary Layers Right Click on Boundary Layers >

Boundary Layer Properties Select the boundaries to have the boundary

details on (all the curved boundaries) Buil d all Change Stretching Factor to 1.1 (or 1.3) Buil d all


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Interactive Meshing Chip and Solderballs New > 3D > Finish Flag Geom > Import > SolderJoints

Mesh with Default Tets (Size Coarse) Delete Tet s Mesh Surface with Triangles Sweep Solderballs

(Add Distribution > 5 layer) Mesh IC Bottom with Free Triangles Sweep IC (Distribution > 3 Layers) Sweep Circuit Board Boundary Layer Mesh Air Rectangle Boundary Layer Props on Bottom of

Circuit Board Boundary > Mesh

Swept Meshing Exercise

Mesh All (Free)

Delete Mesh

Mesh Selected Faces

Undo Mesh

Increase Mesh Size

+ Mesh Selected (Swept)

Mesh Remaining (Free)

Mesh Selected (Swept)

Mixing Hex Meshes with Tet Meshes

New > 3D > Finish Flag Geom> Block > 1x1x1 Geom > Block > 1x1x0.5

(Corner at 0,0,1) Mesh Top Surface with Mapped Sweep Top (Distribution: 5 layers) Mesh Remaining Tets > ERROR Remove last step Mesh > More Operatns > Convert Level = Boundary (Pick Shared) Mesh Remaining Tets > WORKS


ALE MovingMesh

ALE MovingMesh

ALE Moving Mesh

Think of the mesh as a bed of springs As the boundary moves, the springs stretch

NOTE: Need specialeffort to insure front

boundary of valve seatblock does not move


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PREDEFINED Moving Mesh: FSI

New > 2D

Fluid Flow > Fluid Solid Interaction Stationary

Review Model Tree

Much is set up for you Simply indicate what is elastic

Geometry

Geometry > Set units to mm

Rec tang le Width 300 Height 100 Corner (0,0)

Rec tang le Width 5 Height 50 Corner (100, 0)

Declare What is Solid in Fluid-Solid

Default is ALL fluid Open Fluid-Structure Interaction Highlight Linear Elastic Material Choose the Flap

Everything is taken care of for you: Moving Mesh in Solid Free Mesh in Fluid Linkage of Fluid Force on Structure Boundary Conditions on ALE Mesh

Materials

Rt Click on Materials > Open Material Browser Built-in: Water (Add to model)

Rt Click on Materials > Material Rename to Flap Choose Vertical Flap Youngs Modulus = 1000 Poissons Ratio = 0.33 Density = 1000

Boundary Conditions Structure : Rt Click on Fluid-Solid Interaction Choose Solid Mech > Fixed Constraint Pick Bottom Horiz Boundary of Flap

Fluid Inlet : Rt Click on Fluid-Solid Interaction Choose Fluid Flow > Inlet Choose Leftmost vertical inlet boundary V = 0.010

Fluid Outlet : Rt Click on Fluid-Solid Interaction Choose Fluid Flow > Outlet Choose Rightmost vertical inlet boundary P = 0

Mesh + Solve

RtClick on Mesh Free Triangular Pick Size > Coarse

Build

RtClick on Study Compute

2D Plot 1 > Surface Change to Total Velocity Add Contour, Velocity


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Data Sets,Postprocessing

Data Sets,Postprocessing

Results

Results = Postprocessing section

Working with Data Sets Getting Derived Values Creating plots Export = Exporting numerical

data and images Report = Generate HTML report

of the model

Data Sets Solution and Selection

Choose desiredgeometric level

Select the desired

geometric entities

Results can bevisualized only on

the desiredgeometric entities

1

2

3

Derived Values

Results > Derived Values Allows you to evaluate and visualize numerical data Automatically creates table under Results > Table

Evaluates a variable at a pointor geometric vertices

Evaluates global variables,lumped parameters and built-in

physical constants

Menubar options

Point evaluation Cut lines Cut planes Slice

Isosurface

Volume

Surface

Line (edge)

Arrow (in volume)

Streamline

Animate

Exploring the Results Node

Define 3D Heat Transfer Problem CAD Import > Piston for FEA Top : T = 7 00

Bottom: T= 450 Bearing Surf: T = 400Explore different plot types Surface Contour Arrow 3D Isosurfaces Cut Plan es


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Plot on a 2D Cut Plane

Right Click Data Sets Add Cut Plane x-y Plane z = -0.025 Plot

Add 2D Plot Group Use Cut Plane 1 Add Surface T Plot

Right Click Data Sets Add Mirror 2D Select 2D Plot Group > Dataset Mirror 2D Add Contours

Export Cut-Plane Data to File

(Same method could export 3D data to file)

Go to Data Sets Node Right Click on the Dataset you want to export Pick Add to Report

Go to Report Node > Data x Choose the Variable (expression) to export Set the filename path for a .txt file > Export

Open Text File with Excel (or equivalent)

Put a Cut-Line through the Cut Plane

Highlight 2D Plot Node Pick Start Point Pick End Point Highlight 1D Plot Group

To Export Data: Under Datasets: Highlight 1D Cut Line Right Click: Add to Report Highlight: Data1 under

Report Export to Excel

Put a Cut-Line Through the 3D Object

Highlight Plot Group 1

Again Pick Start and End points (This attach to the nearest surface)

Another Dataset Appears: Cut Line 3D

Can Plot it like any other 1D Dataset

Can Export it like any other Dataset

Axisymetric to 3D Visualization

Open Model Library > Acoustics Module >Tutorial Models > PiezoAcoustic Transducer

View Plot Group 1

Right Click on Datasets Node Add Revolution 2D Open Revolution Layers: Change 360 to 135 Right Click on Results > Add 3D Plotgroup Add Isosurface to 3D Plotgroup > Plot

Pressure (Increase to 10 levels) Add a Slice Plot, Quick, xy-planes, 1 Plot Pressure

3D Slices in Time

Open Model Library > COMSOLMultiphysics > Fluid Dynamics >Cylindrical Flow

View Plot Group 1 Right Click on Datasets Node Add Parametric Extrusion 2D Change to Interpolated times Start: 0, End: 7, Step: 1 Add 3D Plot Group Add Surface Plot of Velocity


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Data Export: Value vs Time Resul ts v sTime Model Library > Heat Transfer > Process &

Manufacturing > Disk Brake Highlight Plot Group 1 Right Click Derived Values > Point Evaluation Choose Point 5, Change units to degF Choose Orange = sign creates table Toggle Precision Button Then the Plot Symbol Open Excel (or equivalent) Pick Copy table to Clipboard Paste in Excel

Evaluate Average Disk Pad Temp vs Time

Open Model1 Node

Right Click on Definitions Add Model Couplings > Average Choose Brake Pad Domain Operator Name: BreakPad_Ave Update Solution Add 1D Plot > Global Plot Plot BreakPad_Ave(T)

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