Geometria Tutorial Libre

8/12/2019 Geometria Tutorial Libre

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ANSYS CFX-Mesh

Tutorials

ANSYS WorkbenchRelease9.0

November2004

ANSYS, Inc. is a

UL registered

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Table of Contents

Introduction to the CFX-Mesh Tutorials ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1. List of Features ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2. Legal Notices........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Tutorial 1: Static Mixer........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1. Introduction to CFX-Mesh......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2. Geometry Creation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Tutorial 2: Static Mixer (Refined Mesh) ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

1. Modifying the Mesh Generation......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2. Geometry Modification......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

3. Updating the Geometry in CFX-Mesh ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Tutorial 3: Process Injection Mixing Pipe ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

1. Geometry Creation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Tutorial 4: Circular Vent ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43


2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Tutorial 5: Blunt Body ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 491. Geometry Creation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Tutorial 6: Butterfly Valve......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61


2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Tutorial 7: Catalytic Converter........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71


2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Tutorial 8: Annulus ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81


2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Tutorial 9: Mixing Tube......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87


2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Tutorial 10: Heating Coil ....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93


2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Tutorial 11: Airlift Reactor ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

1. Geometry Creation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Tutorial 12: Room with Air Conditioning ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

1. Geometry Creation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118Tutorial 13: Can Combustor ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

1. Geometry Import........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

2. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Tutorial 14: CAD Cleanup and Meshing ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

1. Mesh Generation ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

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Introduction to the CFX-Mesh TutorialsThe CFX-Mesh Tutorials are a set of tutorial examples which demonstrate how to set up the geometry and mesh

for a variety of different problems. The tutorials cover most of the meshing functionality available in CFX-Mesh

together with some of the most commonly-used geometry features from DesignModeler. Each example results

in the creation of CFX-5 GTM file, which can be imported directly into CFX-Pre. You will find instructions for setting

up CFD simulations using these meshes in the CFX-5 Tutorials which are part of the main on-line help for CFX-

5.

A few of these tutorials require the use of Parasolid or DesignModeler files as a starting point for the geometry

creation. Where such a file is required, the introduction to the tutorial explains this. If you have not already obtained

these files, they should be readily available from the CFX Community Website: go to http://www-waterloo.an-

sys.com/cfxcommunity. This site is available to all registered CFX users. If you have not already got a username

and password, go to http://www-waterloo.ansys.com/cfx/community/apply.htmto apply.

These tutorial instructions are based on ANSYS Workbench 9.0. Some of the tutorials will not work in earlier

versions of ANSYS Workbench since they rely on new features, and other tutorials may be hard to follow. If you

still have ANSYS Workbench 8.1 then you can find tutorial instructions explicitly for this version on the CFX

Community Website using the following link: http://www-waterloo.ansys.com/cfxcommunity/technotes/documentation/CFX-Mesh_8.1/index.html.

If you want to print out the tutorials, then we recommend that you follow the link to the CFX Community Website

to download a package in pdf format, and use this for printing.

Note that if you create the mesh by following the instructions given in these examples, you may not be able to

set up the physics in CFX-5 by using the CFX-Pre session file without getting errors which you need to fix up afte

the session file has finished playing. You can always follow the CFX-5 tutorial instructions manually instead. This

is because the CFX-Pre session files are set up to use the mesh files provided with CFX-5, and some face and body

identifications are different to the ones which you would get by creating meshes by following these instructions

In most cases, you can use the CFX-Pre session file to set up the physics, and then manually apply the location

of the domain and any sub-domains if required. In addition, in the Combustor tutorial, you will also need to setup the Vane Surfaces location manually, and in the Catalytic Converter tutorial, you may need to delete and

recreate the two Domain Interfaces manually.

Can I Skip the Geometry Creation?

If you are only interested in the meshing parts of the tutorials and want to skip all of the geometry creation, then

you should follow the link to the CFX Community Website above to download the DesignModeler .agdbfiles

for the tutorials of interest. You can then use these for each tutorial as follows:

1. Open ANSYS Workbench, and create a new empty project. Save the project with the name suggested

by the tutorial.

2.

At the left side of the Project Page, click on Browse(under Link to Geometry File). Select the ap

propriate .agdbin the file browser which opens up.

3. In the left-hand column, near the top, click on Generate CFX Mesh. Then continue with the tutorial from

the beginning of the Mesh Generation section, ignoring the instructions on opening CFX-Mesh.

http://www-waterloo.ansys.com/cfxcommunityhttp://www-waterloo.ansys.com/cfxcommunityhttp://www-waterloo.ansys.com/cfx/community/apply.htmhttp://www-waterloo.ansys.com/cfxcommunity/technotes/documentation/CFX-Mesh_8.1/index.htmlhttp://www-waterloo.ansys.com/cfxcommunity/technotes/documentation/CFX-Mesh_8.1/index.htmlhttp://www-waterloo.ansys.com/cfxcommunity/technotes/documentation/CFX-Mesh_8.1/index.htmlhttp://www-waterloo.ansys.com/cfxcommunity/technotes/documentation/CFX-Mesh_8.1/index.htmlhttp://www-waterloo.ansys.com/cfx/community/apply.htmhttp://www-waterloo.ansys.com/cfxcommunityhttp://www-waterloo.ansys.com/cfxcommunity


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What if I Don't Have DesignModeler?

If you don't have DesignModeler or don't have a license to run DesignModeler, then you can still work through

the meshing parts of these tutorials as follows:

1. Follow the link to the CFX Community Website above to download the Parasolid Geom.x_t

files for the tutorials of interest.

2. If you have a license to do direct Parasolid import, then these files can be imported into CFX-Mesh directly,following the instructions below.

3. If you don't have a license for direct Parasolid import but do have a license to import files from another

CAD package, then import the Parasolid files into that CAD package, and then use the resulting CAD files

in CFX-Mesh by following the instructions below.

4. If your CAD package does not support the import of Parasolid files either, please contact your support

representative to obtain a set of geometry files that you can import.

The instructions for importing the relevant CAD files (Parasolid or otherwise) into CFX-Mesh are as follows:

1. Open ANSYS Workbench, and create a new empty project. Save the project with the name suggested

by the tutorial.2.

At the left side of the Project Page, click on Browse(under Link to Geometry File). Select the ap-

propriate CAD filename in the file browser which opens up.

3. In the left-hand column, near the top, click on Generate CFX Mesh. Then continue with the tutorial from

the beginning of the Mesh Generation section, ignoring the instructions on opening CFX-Mesh.

If you import the Parasolid files into your CAD package and then import the resulting CAD file into CFX-Mesh

you may occasionally find that whilst the geometry still looks the same afterwards, certain features may change

subtly due to differences in the geometry representation in your CAD package.

Specific tutorials will need minor adaptations as a result of importing Parasolid files (or other CAD files) directly:

Tutorial 2: Static Mixer (Refined Mesh)- You will not to be able to continue with the tutorial beyond the

point at which you write the file StaticMixerRefMesh.gtmas this relies on being able to modify the

geometry in DesignModeler. It is recommended that you read through the section called Updating the

Geometry in CFX-Mesh if you want to see how to update your geometry in CFX-Mesh, as this is not

covered by any other tutorial.

Tutorial 6: Butterfly Valve- The units after you import the Parasolid file are always meters, but the tutorial

instructions expect the geometry to be in millimeters. You will need to enter all given values in the correct

units of meters i.e. when the tutorial asks you to set a Default Body Spacing of 4.5 mm, you must enter

0.0045 m.

Tutorial 7: Catalytic Converter- The units after you import the Parasolid file are always meters, but thetutorial instructions expect the geometry to be in centimeters. You will need to enter all given values in

the correct units of meters i.e. when the tutorial asks you to set a Default Body Spacing of 1.0 cm, you

must enter 0.01 m.

Tutorial 8: Annulus- The units after you import the Parasolid file are always meters, but the tutorial instruc-

tions expect the geometry to be in feet. You will need to enter all given values in the correct units of

meters i.e. when the tutorial asks you to set a Default Body Spacing of 0.02 ft, you must enter 0.006 m.

Conversions for the other values are given in the tutorial instructions.

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Tutorial 9: Mixing Tube- The units after you import the Parasolid file are always meters, but the tutorial

instructions expect the geometry to be in millimeters. You will need to enter all given values in the correc

units of meters i.e. when the tutorial asks you to set a Default Body Spacing of 0.6 mm, you must enter

0.0006 m.

Tutorial 10: Heating Coil

The DesignModeler geometry puts both solid bodies into one part and creates shared faces between

them, so that CFX-Mesh can create one mesh containing both bodies. The result of the direct Parasolidimport will be to have two bodies each in a separate part, so CFX-Mesh will create one file Heating-

CoilMesh.gtmwhich contains two separate meshes, and hence two separate assemblies in CFX-Pre

This file can be used in CFX-Pre as usual; an example of how to deal with having multiple assemblies

in CFX-Pre is detailed in the CFX-5 example Tutorial 10: Flow in a Catalytic Converter (although you

must use Fluid-Solid Interfaces for this example since you are connecting a fluid domain to a solid

domain).

You are advised that if you wish to work through the CFX-5 example after creating your mesh, you

should use the CFX-Pre Mesh file HeatingCoilMesh.gtmprovided by your CFX-5 installation, since

the tutorial instructions were written expecting one mesh containing both bodies.

In addition, since you have two separate parts in the CFX-Mesh session, you should NOT enable Surface

Proximity as suggested by the tutorial instructions: if surface proximity is enabled on a multi-partgeometry, then the mesher sees the faces in each part as being very close together but not coincident

and so attempts to refine the mesh in this region far more than is required for this tutorial.

The tutorial instructions ask you to suppress one of the Bodies contained in Part 3. Instead, you should

click on the name of each part in turn, and see which one corresponds to the coil and which one to

the container. Then right-click over the part which corresponds to the coil, and select Suppress. Later

in order to see which 2D Regions you have selected, suppress the other part in the same way. After-

wards, unsuppress both parts by right-clicking on their names and selecting Unsuppress.

Tutorial 11: Airlift Reactor

The units after you import the Parasolid file are always meters, but the tutorial instructions expect thegeometry to be in centimeters. You will need to enter all given values in the correct units of meters

i.e. when the tutorial asks you to set a Default Body Spacing of 1.0 cm, you must enter 0.01 m.

The DesignModeler geometry puts both solid bodies into one part and creates shared faces between

them, so that CFX-Mesh can create one mesh containing both bodies. The result of the direct Parasolid

import will be to have two bodies each in a separate part, so CFX-Mesh will create one file Bubble-

ColumnMesh.gtmwhich contains two separate meshes, and hence two separate assemblies in CFX-

Pre. This file can be used in CFX-Pre as usual; an example of how to deal with having multiple assemblies

in CFX-Pre is detailed in the CFX-5 example Tutorial 10: Flow in a Catalytic Converter.

You are advised that if you wish to work through the CFX-5 example after creating your mesh, you

should use the CFX-Pre Mesh file BubbleColumnMesh.gtmprovided by your CFX-5 installation, since

the tutorial instructions were written expecting one mesh containing both bodies.

When you create the Composite 2D Region DraftTube, you may find that the selection rectangles

appear in the order (from left to right): outside of the column, draft tube face (inside), draft tube face

(outside), face from symmetry plane, instead of the order listed in the tutorial instructions. You can

tell which order they appear in, since the selection rectangle corresponding to the draft tube (outside

will be the same color as the outside of the column. This is the one which you require.

Tutorial 13: Can Combustor

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Introduction to the CFX-Mesh Tutorials



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Section 2: Legal Notices


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8


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Tutorial 1: Static Mixer

This example shows geometry creation and meshing for a simple static mixer. It assumes that you have never

used ANSYS Workbench before and gives detailed instructions on every step needed to construct the example

The following geometry and meshing features are illustrated:

basic geometry creation including Revolve and Extrude operations; and

basic meshing operations.

If you want to skip the geometry creation part of the tutorial, then see the instructions in Introduction to the

CFX-Mesh Tutorials. However, even if you are not going to work through the geometry creation section, it may

be worth reading through it if you have not used ANSYS Workbench before, since it contains some background

information which is also applicable to CFX-Mesh.

1. Introduction to CFX-Mesh

In order to create a mesh using CFX-Mesh, the steps are as follows.

1. Create the Geometry.

2. Define Regions.

3. Define the Mesh Attributes.

4. Create the Surface Mesh (this is optional).

5. Create the Volume Mesh.

You can create the geometry either in ANSYS Workbench or by importing it from a CAD package. The geometry

creation tool in ANSYS Workbench is DesignModeler, a parametric feature-based solid modeler. Most of the CFX

Mesh Tutorial Examples include instructions on creating geometry in DesignModeler, although for full document-

ation you should consult the DesignModeler Help.



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The remaining four steps are all carried out within CFX-Mesh. The creation of the surface mesh is optional; if it

is not created explicitly, then it will be generated as part of the creation of the volume mesh.

ANSYS Workbench helps you to manage all of the files created by DesignModeler and CFX-Mesh by the use of

the Project Page. Your first step after opening ANSYS Workbench will be to create a new project, and by returning

to the Project Page (which is available at any point during your ANSYS Workbench session) you can switch

between DesignModeler and CFX-Mesh, add new files to the project, and so on. We recommend that you create

each new project in a new directory so that all the files for each project are kept separate. You can also then run

the CFX-5 software from the same directory after generating the mesh.

2. Geometry Creation

Creating the Project

The first step for any new case is to create the project.

1. Open ANSYS Workbench. On Windows, this can be done by going to the Start Menu>Programs section

and selecting ANSYS 9.0>ANSYS Workbench. On UNIX, this can be done by running /an-

sys_inc/v90/aisol/startpageif your installation used the default settings. Otherwise, you should run

install_dir/ansys_inc/v90/aisol/startpage.2. Start a new project from scratch by selecting Empty Projectfrom the Newsection of the Startwindow

in the middle of the ANSYS Workbench window. (Depending on which modules are available, you may

find that you need to scroll down to see Empty Projecticon.) The Project Page will appear, containing

Unsaved Project.

3. The next setting is to tell ANSYS Workbench where you want your project files to be created. Select

File>Save, and save the project as StaticMixer.wbdbin a new directory of your choice. This directory

will be the default location for all of the project files which you will create during the tutorial.

You can then open DesignModeler in order to start creating the geometry.

1.At the left side of the Project Page, click on New geometry(under Create DesignModeler Geo-

metry).

2. In the popup window, select Meteras the desired length unit.

Overview of DesignModeler

Once DesignModeler opens up, you will be able to see four main areas to the window.




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The Model View displays the geometry. The geometry can be manipulated using the mouse buttons. Fo

example, holding down the middle mouse button and moving the mouse over the Model View will rotate

the geometry. Clicking the right mouse button over the Model View will bring up a menu which includes

various options for manipulating the model as well as other options which are particular to what geometryoperation you are performing or what objects are selected. To put the model into a particular view, you

can also use the Triad which is displayed at the bottom right corner of the Model View: click on one of the

axes or on the cyan-colored ball to move the model. You can zoom out to view the entire model by right-

clicking over the Model View and selecting Zoom to Fit. You can zoom in to a selected area by clicking

with the right mouse button and dragging the mouse over the required area whilst holding down the

button.

The Details View shows the details for the selected object. No object is selected when DesignModeler is

first opened, so it is blank in the picture above. It can be used to edit the details (including the name of

the object) by simply typing over the information to be updated.

The Tree View shows all of the features of the geometry, and their states. When DesignModeler is first

opened, only the three default planes (XYPlane, ZXPlane, and YZPlane) are present, together with anentry which shows you that there are currently 0 Parts, 0 Bodies. As you perform geometry creation op-

erations, the structure of the tree will expand to show these. The geometry operations such as Extrude

and Revolveare applied from the top of the tree downwards. For example, in the tree shown below, Ex

trude2 was the first operation, followed by Revolve2.


Section 2: Geometry Creation


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The symbols next to the operations and features indicate their status:

MeaningSymbol

Everything is OK.

The item is suppressed i.e. not taking any effect (it can be unsuppressed later).

Something is wrong with the item e.g. you tried to generate it before you had fully specified it, or you

modified one of the features above it which makes the specifications of the item invalid. (You can see

the error messages by right-clicking on the object and selecting Show Errors and Warnings.)

The item needs to be generated or re-generated (because changes to the settings have been made since

it was last generated).

The sketch will remain visible even when not selected.

The Body has been hidden (made invisible).

The top part of the window contains the various menus and toolbars.

DesignModeler has two main modes of operation, and you will have to switch between them as you build up

your model. In Modeling Mode, the Tree View is shown, as in the picture above. However, DesignModeler uses

sketches(collections of edges in a plane) to build up solid models, and to create these sketches, you need to be

in Sketching Mode. To switch between the two modes, the tabs (Sketchingand Modeling) at the bottom of the

Tree View are used: simply click on the appropriate tab to switch between the two modes.

The area which is occupied by the Tree View when you are in Modeling Mode is taken up with the sketching

toolboxes (Draw, Modify, Constraints, Dimensionsand Settings) when in Sketching Mode. To switch between

them, simply click on their names.

Recovering from Mistakes

You are certain to make mistakes as you build up your geometry, so it is important to know how to recover from

these.




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If you are in Sketching Mode, then the Undobutton in the Undo/Redo Toolbar towards the top of the window

can be used to undo sketching operations. The Backbutton (accessed by right-clicking over the Model View)

can be used to undo the selection of (for example) the last point in a polyline, whilst sketching.

If you are in Modeling Mode, and you have not yet generated your feature (such as Extrude) you can either just

make further changes in the Details View, or you can delete it by right-clicking on its name in the Tree View and

selecting Delete.

After generating a feature, you can delete it by selecting it in the Tree View and using the Deleteon the rightmouse menu. If you have generated a feature e.g. Extrude and then realize (for example) that you selected the

wrong sketch to define it, you will need to use the Edit Selectionsfeature. This is accessed by selecting right-

clicking over the name of the feature in the Tree View and selecting Edit Selections: you will then be able to

edit the selections by using the Details View as usual.

Creating the Solid

You need to start creating the Static Mixer geometry by creating a sketch to make the main body of the mixer.

1. Click on ZXPlanein the Tree View towards the top left of the screen.

2. Click on the Sketching tab (underneath the Tree View) to work on the sketch.

Each sketch is created in a plane. By selecting the ZXPlaneimmediately before going into sketching mode, you

ensure that the sketch you are about to create is based on the ZXPlane.

Before starting to create your sketch, it helps to set up a grid of lines on the plane in which the sketch will be

drawn. The presence of the grid allows the precise positioning of points (when Snapis enabled).

1. Click on Settings(in the Sketching tab) to open the Settings Toolbox.

2. Click on Gridand turn ON Show in 2Dand Snap.

3. Click on Major Grid Spacingand set it to 1.

4. Click on Minor-Steps per Majorand set it to 2.

5. You now need to zoom in to see the effect of changing the Minor-Steps per Major. Click the right mouse

button to the top left of the plane center in the Model View and drag a box across it to zoom into the

middle of the grid. When you release the mouse button the model will be magnified to show the selected

area.




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You now have a grid of squares with the smallest squares being 50 cm across. Because Snapis enabled, you will

only be able to select points that are on this grid to build your geometry, and this can often help to position

objects correctly.

1. Select the Draw Toolbox from the Sketching tab.

2. Click on Polylineand then create the shape shown below:

a. Click on the grid in the position where one of the points from the shape needs to be placed (itdoesn't matter which point).

b. Then click on each successive point to make the shape.

c. If at any point you click on the wrong place, just click with the right mouse button over the Model

View and select Backfrom the right mouse button menu to undo the point selection.

d. To close the polyline after selecting the last point, click with the right mouse button to bring up a

menu and choose Closed End.

Note that the longest straight line (4 m long) in the diagram below is along the z-axis (located at x = 0

m).

You will now create the main body of the mixer by revolving the new sketch around the Z-axis.

1.

Select Revolvefrom the 3D Features Toolbar. This toolbar is located above the Model View.

2. Details of the Revolve operation are shown in the Details View at the bottom left of the window. Leave

the name of the Revolve as the default, Revolve1.

3. The Base Objectis the name of the sketch to be revolved. It defaults to the sketch which you have just

created, Sketch1, so this setting does not need to be changed.

4. The Axisfor the rotation does not have a default setting. In the Model View, click on the grid line which

runs along the Z-axis and then click on Applyin the Details View. You should find that the text next to

Axisnow changes to Selected. If instead it changes to Not Selectedwith a yellow background, click on

the text Not Selectedand then try selecting the axis again in the Model View, remembering to press

Applyin the Details View after you have selected it.




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5. Leave Operationset to Add Materialsince you need to create a solid. (The other options allow you to

modify existing solids and to deal with multiple solids.)

6. The sketch needs to be revolved by a full 360 degrees, so change Anglefrom 30degrees to 360degrees

Leave the other settings as default.

7.

To activate the revolve operation, you need to click on Generate. This can be selected from the

menu which appears when you click with the right mouse button almost anywhere in the window, or

from the 3D Features Toolbar towards the top of the window.

After generation, you should find you have a solid as shown below.

Now you need to create the two side pipes. This involves creating and extruding two new sketches. To make it

easier to see the grid when creating the sketches, the first step is to make the solid invisible for now.

1. In the Tree View, click on the plus sign next to 1 Part, 1 Bodyto open up the tree structure.

2. Position your cursor over the text Solidand then click with the right mouse button and select Hide Body

3. Select ZXPlanein the Tree View again, and create a new sketch based on this plane by using the New

Sketch ( ) button on the Active Plane/Sketch Toolbar, which is located above the Model View.

4. Select the Sketching tab.

5. Create a circle as shown in the picture below:

a. Select the Draw Toolbox.

b. Select Circle, click on the grid at the center of the circle and then drag the mouse to define the ra-

dius.




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Now you need to extrude this sketch to make the first side-pipe.

1.Select Extrudefrom the 3D Features Toolbar. This toolbar is located above the Model View.

2. In the Details View at the bottom left of the window, change Directionto Reversed, in order to extrude

in the opposite direction to the plane normal.

3. Change the Depthto 3m. The rest of the settings can be left as their default. The Add Materialsetting

will mean that material is added to the existing solid, rather than a new solid being created.

4.

To activate the extrude operation, you need to click on Generateas before.

In order to see the result of this, you will have to make the solid visible again:

1. In the Tree View, position your cursor over the text Solidand then click with the right mouse button and

select Show Body.

2. Click the middle mouse button over the middle part of the Model View and drag the mouse about with

the button held down to rotate the model. Check that the Solid looks like the picture below when rotated

into a viewing position so that the side-pipe is clearly visible.




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select Hide Body.

To create the other side pipe, the same operations are used.

1. Select ZXPlanein the Tree View again, and create a new sketch based on this plane by using the New

Sketch ( ) button on the Active Plane/Sketch Toolbar, which is located above the Model View.


3. Right-click over the Model View and select View>Isometric Viewto put the sketch back into a sensible

viewing position. Then right-click again and select Zoom to Fitto zoom into the sketch, if it appears too

small.

4. From the Draw Toolbox, select Circleand then create the second circle shown in the picture below:

1.

Select Extrudefrom the 3D Features Toolbar.

2. In the Details View, set Directionto Normal, in order to extrude in the same direction as the plane normal




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3. Change the Depthto 3m.

4.

To activate the extrude operation, you need to click on Generateas before.


select Show Body.

The geometry is now complete.

1. Select File>Saveand accept the default filename.

Before moving on, practise using the mouse to manipulate the model in the Model View. This is essential to be

able to move the model into positions which are good for selecting or looking closely at particular parts of the

model.

1.

Ensure that Rotatemode is selected from the Rotation Modes Toolbar at the top of the window.

This is the default mode.

2. Click the middle mouse button over the middle part of the Model View and drag the mouse about with

the button held down to rotate the model. You have already met this way of moving the model around(free rotation) earlier in the tutorial. It is the most common way to move the model.

3. Now move the mouse button towards the top left of the Model View. As you get near to the top left, the

cursor should change from to . If you now click the middle mouse button (with the new

cursor showing) and drag the mouse about with the button held down, you will be able to rotate the

model about an axis which points out of the screen (roll). This can be useful if you are trying to get the

model into a particular position.

4. There are two more types of rotation. Move the cursor back towards the left of the screen. Very close to

the left edge of the Model View, you will find that the cursor changes to . If you click the middle

mouse button with this cursor showing, then the rotation is constrained to be around a vertical axis in

the plane of the screen. If you move the cursor to the top of the Model View, you get the other cursor

. If you click the middle mouse button with this cursor showing, then the rotation is constrained

to be around a horizontal axis in the plane of the screen.

Which type of rotation mode you get always depends on the position of the cursor. The picture below

shows the areas of the Model View which correspond to each type of rotation. Note that the circular region

where you get free rotation will always fill the smallest dimension of the window.




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5. Put the model back into the Isometric View by clicking on the cyan-colored ball in the Triad at the bottom

right of the Model View.

Now suppose that you wanted to zoom in on one of the pipe ends.

1. Right-click on the Model View to the top left of the pipe end which is visible and drag a box across it.

When you release the mouse button, the model will expand so that the contents of the box are visible

across the whole Model View.

2. Try rotating the model. You will find that the model by default rotates around the model center, so the

pipe end quickly moves out of view. You can change this as follows. Bring the pipe end back into view,

and click once with the left mouse button on the pipe end. DesignModeler will place a small red sphere

where you clicked, and then move the model so the small red sphere moves to the middle of the Mode

View. If you now try rotation, you will find that the model rotates around the small red sphere, not the

model center, so the pipe end is always in view. (To change back to rotating around the model center,

click once with the left mouse button anywhere in the Model View that is away from the model itself.)

3. Zoom out again by holding down the Shift key on the keyboard, pressing the middle mouse button and

dragging the mouse downwards. You can zoom in by dragging the mouse upwards instead. An altern




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ative way of enabling the Zoom functionality is to select Zoommode from the Rotation Modes

Toolbar. Once this is enabled, zooming in and out is done by clicking and dragging with the left mouse

button. If Zoommode is selected, then most of the ways that you just tried rotating the model are no

longer available; you must select Rotatemode again to use them.

There are two more useful ways to manipulate the model in the Model View.

1. Pan (or Translate) the model by holding down the Ctrl key on the keyboard, pressing the middle mouse

button and dragging the mouse around. An alternative way of enabling the Pan functionality is to select

Panmode from the Rotation Modes Toolbar. Once this is enabled, panning is done by clicking and

dragging with the left mouse button. Again, you must reselect Rotatemode to use most of the

different rotation methods.

2. Finally, center the model in the Model View and resize it so that it is all visible by selecting Zoom to Fit

from the Rotation Modes Toolbar.

In the rest of this tutorial and all of the subsequent tutorials, you should use the functionality described above

to manipulate the model in any way which is convenient.

3. Mesh Generation

In order to set up the mesh, you must first move out of DesignModeler and into CFX-Mesh.

1. At the top of the ANSYS Workbench window, you should be able to see two tabs: StaticMixer [Project]

and StaticMixer [DesignModeler]. Click on StaticMixer [Project]to return to the Project Page.

2. In the left-hand column, near the top, you should now see an entry Generate CFX Mesh. Click on this.

3. CFX-Mesh will open up. At first glance it looks very similar to DesignModeler.




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Overview of CFX-Mesh

CFX-Mesh is designed to have the same look and feel as DesignModeler. In particular, this means that you canuse the same mouse controls to manipulate the model.

One important difference between DesignModeler and CFX-Mesh is connected to the order of the items in the

Tree View. In DesignModeler the Tree View shows items in the order that they were created, and the order affects

the final geometry. In CFX-Mesh the order of the items in the Tree View are not important and all items of the

same type are grouped together, independent of when they were created.

You will be able to see that various items are already present in the Tree View in DesignModeler; these are the

default items and contain default settings. Some of the symbols next to items in the Tree View have slightly dif

ferent implications in CFX-Mesh than they did in DesignModeler. In CFX-Mesh, the meanings are as follows:

MeaningSymbol

Everything is valid.

Everything is valid but the item has been automatically changed and you may wish to double-check the settings

This may occur, for example, if you have performed a geometry update which has resulted in a face no longer

existing: if that face appeared in the location list for any mesh feature, then it will have been removed automat-

ically as part of the update and so the mesh feature will be marked with this status symbol.

This means that there is something invalid about the definition of the item or one of its sub-items (which will

also be marked with the same symbol). Often this will be because no required selection has been made.


Section 3: Mesh Generation


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MeaningSymbol

The item is suppressed (inactive).

The item is suppressed and will be invalid when it is unsuppressed.

These status symbols only apply to Preview Groups.

If the symbol underneath the yellow flash is a green tick, then the Preview Group is valid but either the meshhas not been generated or the generated mesh is out-of-date i.e. it does not reflect the current mesh settings.

To generate an up-to-date mesh for the Preview Group, right-click over its name and choose Generate This

Surface Mesh. To generate an up-to-date mesh on all Preview Groups, right-click over Previewin the Tree View

and choose to Generate All Surface Meshes.

If the symbol shows the yellow lightning bolt but the symbol underneath it is a yellow tick, then the Preview

Group is both out-of-date (see above) and automatically changed. Refer to the table entry for a yellow tick

symbol for details of what might cause an automatic change to a Preview Group.

If the symbol shows the yellow lightning bolt but the symbol underneath it is a red exclamation mark, then the

Preview Group is both out-of-date (see above) and invalid. You must make the Preview Group valid (by making

a valid selection for its Location) before you can generate or regenerate it.

This indicates that an item contains associated sub-items . Left-click on the symbol to expand the item anddisplay its contents.

Left-click on the symbol to close the item so that its contents are not visible in the tree.

The generation of the surface and volume mesh is controlled by the various features that you can access in CFX-

Mesh. The type of controls available depend on the mesher used. By default, you are using the Delaunay Surface

Mesher for surface meshing and Advancing Front Volume Mesher for volume meshing.

In this first example, you will only set up the most basic features for controlling the mesh generation. Only the

basic length scale of the mesh will be specified.

Setting up the Regions

The first step is to define some regions on the geometry. Composite 2D Regions are created from the solid faces

(primitive 2D Regions) of the geometry. They can be used in CFX-Pre to assign boundary conditions, such as inlets

and outlets, to the problem. You do not need to create Composite 2D Regions at all in CFX-Mesh, but it is easier

to name and group faces into Composite 2D Regions in CFX-Mesh than it is to select the corresponding mesh

in CFX-Pre. This example uses an inlet boundary condition at the entrance to each of the two side pipes, an

outlet boundary condition on the end of the funnel outlet and a wall boundary condition for the remaining

surfaces.

Note There is an important distinction between primitive 2D Regions and the underlying solid faces,

which applies when the model has more than one solid. This is explained in the Mesh Generation sectionof the Heating Coil tutorial.

If you look at the Tree View, you can see that under Regions, one Composite 2D Region is defined already, called

Default 2D Region. This region will always contain all of the faces of the model which you have not explicitly

assigned to another Composite 2D Region.

Create the Composite 2D Region for the first inlet:

1. Right-click over Regionsin the Tree View.




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2. Select Insert>Composite 2D Region.

3. A new object, Composite 2D Region 1, is inserted under Regionsin the Tree View. In the Details View

there will be two buttons, Applyand Cancel, next to Location, and this means that you are ready to

select the face from the Model View.

4. In the Model View, click on the circular face at the end of the side pipe which is at the position with the

lowest value of the Y-coordinate. This will turn green to show that it has been selected, as in the picture

below. You can rotate the model to make it easier to select the appropriate face by holding down the

middle mouse button and moving the mouse over the geometry.

5. Click on Applyin the Details View.

6. Change the name of the region to in1: right-click over the name, select Renameand then type over the

existing name.

Now create the second inlet:

1. Right-click over Regionsin the Tree View.

2. Select Insert>Composite 2D Region.

3. A new object, Composite 2D Region 1, is inserted under Regionsin the Tree View. In the Model View,

click on the circular face at the end of the side pipe which is at the position with the highest value of the

Y-coordinate.


5. Change the name of the region to in2by right-clicking over the existing name.

Finally, create the region for the outlet:

1. Right-click over Regionsin the Tree View and select Insert>Composite 2D Region.

2. Select the circular face at the bottom of the mixer vessel, with the lowest value of the Z-coordinate.


4. Change the region name to out.

It is not necessary to create a fourth Composite 2D Region for the walls of the static mixer. This is because any

remaining faces which are not explicitly assigned to a Composite 2D Region are automatically assigned to the

2D Region named Default 2D Region. You can use this region in CFX-Pre to define the location of your wall

boundary condition.




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Setting up the Mesh

You will only set a single size for all of the elements, in this tutorial. The next tutorial will then improve upon this

coarse mesh.

1. Click on Default Body Spacingin the Tree View, which is contained in Mesh>Spacing.

2. In the Details View, change Maximum Spacingto 0.3m. This is a coarse length scale for this model, but

is reasonable for a first run to generate an approximate solution and to test that the model is workingcorrectly.

3. Press Enter on the keyboard to set this value.

The remaining settings will be left as their default.

Generating the Surface Mesh

You will now have a look at the surface mesh to see the effect of the chosen length scale.

1. Click on the plus sign next to Previewin the Tree View to open it up.

2. Right-click over Default Preview Groupand select Generate This Surface Mesh. The Default PreviewGroup always contains all faces in the geometry, so the mesh will be generated everywhere.

During the generation of the surface mesh, the progress will be displayed using the slider bar which appears to

the bottom left of the CFX-Mesh window.

1. You can modify the way that the mesh is displayed by clicking on Previewin the Tree View and changing

the options shown in the Details View. For example, by changing the Display Modeyou can switch to

display the mesh in Wire Meshrather than with solid faces. Simply click on the name Default Preview

Groupto redisplay the surface mesh using the new settings.

It is not necessary to create the surface mesh within CFX-Mesh, since if it has not been created explicitly it will

be automatically generated when you create the volume mesh. However, in many of these tutorials, you will

create the surface mesh first, to demonstrate the effect of various mesh settings. It is generally a good idea to

check the surface mesh before creating the volume mesh, to ensure that any settings you have made have the

desired effect.




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Generating the Volume Mesh

The volume mesh and all of the region information required for CFX-Pre is stored in a CFX-Pre Mesh file *.gtm.

The CFX-Pre Mesh File is read into CFX-Pre at the start of the simulation definition.

Generate the volume mesh as follows.

1. Right-click on Meshin the Tree View and select Generate Volume Mesh.

2. Choose to save the CFX-Pre Mesh File as StaticMixerMesh.gtm.

During the generation of the volume mesh, the progress will be displayed using the slider bar which appears to

the bottom left of the CFX-Mesh window. When the volume mesh is complete, the slider bar will disappear and

you will be able to take control of the user interface again.

The mesh is now complete.

1. Select File>Saveto save the CFX-Mesh database as StaticMixer.cmdbin the same directory as the

other project files.

2. At the top of the ANSYS Workbench window, you should be able to see three tabs: StaticMixer [Project]

StaticMixer [DesignModeler]and StaticMixer [CFX-Mesh]. Click on StaticMixer [Project]to returnto the Project Page.

3. Select File>Saveto save the project.

If you want to continue by working through the CFX-5 example Tutorial 1: Flow in a Static Mixer using the

newly-generated mesh, and have CFX-5.7.1 in ANSYS Workbench installed on your machine, then follow these

steps:

1. On the Project Page, a new entry will have appeared when you generated the file: Advanced CFD. Unde

this entry, double-click on StaticMixerMesh.gtmto open up CFX-Pre.

2. Once CFX-Pre has opened, choose File>Save Simulation As...to save the simulation as StaticMixer.

3. Select Tools>Quick Setup Mode...to enter the Quick Setup Mode that this tutorial uses.

4. Work through the CFX-5.7.1 tutorial, missing out the instructions in the section Creating a New Simula

tion. Note that you do not need to copy the sample file StaticMixerMesh.gtmto your working directory

if you have just created the mesh in CFX-Mesh, since you will want to use your new mesh and not the

one supplied with CFX-5. For the Importing a Mesh section, the only action that you need to carry out

is to select Assemblyfrom the Select Meshdrop-down list, as the mesh is loaded automatically when

you start CFX-Pre in the manner described above.

If you do not have CFX-5.7.1 in ANSYS Workbench installed or do not want to work through the CFX-5 example

then:

1. Exit from ANSYS Workbench by selecting File>Exit.




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Tutorial 2: Static Mixer (Refined Mesh)

This example modifies the mesh and geometry for the static mixer example created in the previous example,

and assumes that you have access to the files created as part of that example. The following geometry and

meshing features are illustrated:

modifying an existing mesh setup;

Inflation, and

geometry update.

1. Modifying the Mesh Generation

Opening the Existing Project

1. Open ANSYS Workbench.

2. In the main part of the window, click on the existing StaticMixer project. If it does not appear in the list

of recent projects (perhaps because you moved the files), then use Browseto locate the project file

StaticMixer.wbdbinstead.

3.

To open CFX-Mesh, double-click on StaticMixer.

CFX-Mesh will now be opened with the geometry and mesh settings from the previous tutorial.

Modifying the Mesh Settings

The first step is to create a refined mesh size over the whole geometry.

1. Click on Default Body Spacingin the Tree View, which is contained in Mesh>Spacing.

2. In the Details View, change Maximum Spacingto 0.2m. This is a smaller length scale for the model than

set previously (0.3 m).



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3. Press Enter on the keyboard to set this value.

The next step is to create an Inflated Boundaryon the walls of the mixer. Creating inflated boundaries generates

prismatic elements from the surface by inflating triangular elements into the solid. As a result, near the wall

boundaries there will be layers of flat prismatic (wedge-shaped) elements which provide a smaller mesh length

scale in the direction perpendicular to the wall. This provides better resolution of the velocity field near the wall,

where it changes rapidly.

Inflation can greatly improve accuracy, particularly in a model with a high aspect ratio, such as a long narrowpipe, or in a model where turbulence is significant. Inflation should always be used when you are interested in

lift, drag or pressure drop in the model.

Away from the wall boundaries, the mesh elements will be tetrahedral as they were in Tutorial 1.

First, you will set the parameters used to control the inflation process, and then you will create the Inflated

Boundary itself.

1. Click on Inflationin the Tree View.

2. In the Details View, set Number of Inflated Layersto 5. This will give five layers of prism elements.

3. Set Expansion Factorto 1.3. This controls how fast the thickness of the prism elements grows in suc-cessive layers away from the wall.

4. Leave the other settings as their default values.

5. In the Tree View, right-click on Inflationand select Insert>Inflated Boundary.

6. Click on Default 2D Regionin the Tree View to select the faces which are in the Default 2D Region for

the Inflated Boundary. Click on Applyin the Details View. The text should change to read 1 Composite.

7. Set Maximum Thicknessto 0.2m.

This creates an Inflated Boundary that uses all the faces in the Default 2D Region. If you later change the 2D Region

settings so that the Default 2D Region contains different faces, the Inflated Boundary will automatically update

to always use the faces in the Default 2D Region at the time when the mesh is generated.

Generating the Surface Mesh

You will now have a look at the surface mesh to see the effect of the chosen length scale and the inflation,

compared to the mesh you generated for the previous example. You can use the existing Preview Group to display

the surface mesh.

1. Right-click over Default Preview Groupand select Generate This Surface Mesh.




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You should be able to see that this mesh is finer (has more surface elements) that the mesh you generated in

the first example. Also, note that there are triangular prism elements near the walls of the mixer vessel, the edges

of which can be seen when you look at mesh on the two inlets or outlet.

Generating the Volume Mesh

Finally, you can generate the volume mesh.

1. Right-click on Meshin the Tree View and select Generate Volume Mesh.

2. Save the GTM File as StaticMixerRefMesh.gtm.

The mesh is now complete.

1. Select File>Saveto save the CFX-Mesh database.

From this point, you could go straight into the CFX-5 example Tutorial 2: Flow in a Static Mixer (Refined Mesh)

using the newly-generated mesh. However, this tutorial continues by modifying the geometry in order to illustrate

how to set dimensions on geometry objects and how to tell CFX-Mesh to use the updated geometry. Setting

dimensions is essential when creating geometry features which have dimensions which are not simple fractions

of the model units, and so cannot use the grid for positioning the points and lines in the sketches.


Section 1: Modifying the Mesh Generation


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2. Geometry Modification

In this section, you will change the radius of the inlet pipes to 0.4 m from the initial 0.5 m, without using the grid

to position the circle. You will then extend the outlet pipes.

1. At the top of the ANSYS Workbench window, you should be able to see two tabs: StaticMixer [Project]

and StaticMixer [CFX-Mesh]. Click on StaticMixer [Project]to return to the Project Page.

2.To open DesignModeler, double-click on StaticMixer.

3. Once DesignModeler has opened, click on the plus sign next to ZXPlaneand then select Sketch2in the

Tree View, noting which circle it contains. Choose the Sketching tab.

4. Click on Dimensions(in the Sketching tab) to open the Dimensions Toolbox.

5. Click on Radiusand then select the circle which forms Sketch2 from the Model View.

6. Click somewhere in the Model View to choose where the label for this dimension will be placed (this

does not affect the model in any way, it is purely for display purposes).

7. If you now look in the Details View at the bottom left of the screen, you will find a section headed Dimen-

sions, which contains the radius R1, set to 0.5 m. For now, change the radius to be 0.4m .8.

Click on Generateto activate the change.

You will see that both of the side pipes now have a reduced radius as required. The radius of both the pipes

changed simultaneously as the property of AutoConstraints is turned on by default. This automatically detects

dimensions which are equal and constrains them to be equal so that when one changes, the other does also.

See the DesignModeler documentation for more details.

You have now explicitly defined the dimension (radius) of the inlet pipe radii and can easily change it again if

needed, perhaps if you change the geometry or if you made a mistake when originally specifying the radius.

Whenever you are asked in later tutorials to create a geometry object of a particular size, you can either set up

the grid to enable precise positioning of the geometry, or create the geometry at approximately the right sizeand then use the Dimensions Toolbox to specify the dimension exactly.

Now you can extend the outlet pipe. The first part of the extension requires a Revolve operation. However, you

need to revolve the end surface of the existing outlet pipe, which isn't currently defined as a sketch or plane, so

first you need to construct the appropriate plane from which to revolve.

1.

Create a new plane by using the New Plane ( ) button on the Active Plane/Sketch Toolbar, which is

located above the Model View.

2. In the Details View, set Typeto be From Faceand Subtypeto be Outline Plane.

3. In the Details View, click in the box next to Base Face. There will now be two buttons, Applyand Cancel,and this means that you are ready to select the face from the Model View.

4. In the Model View, click on the circular face at the end of the outlet pipe, which is at the position with

the lowest value of the Z-coordinate. Click on Applyin the Details View.

5.

Click on Generateto create the plane.

The Revolve operation requires the specification of a rotation axis. Since this rotation will not be around any of

the main coordinate axes, a sketch containing a single line to act as the required axis will be created.




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1. Select the new plane Plane4in the Tree View again, and create a new sketch based on this plane by using

the New Sketch ( ) button on the Active Plane/Sketch Toolbar, which is located above the Model

View.


3. Click on Settings(in the Sketching tab) to open the Settings Toolbox.

4. Click on Gridand turn ON Show in 2Dand Snap.5. Click on Major Grid Spacingand set it to 1.

6. Click on Minor-Steps per Majorand set it to 2.

7. From the Draw Toolbox, select Lineand then create a line which is parallel to the Y-axis and is positioned

at x = 2 m. You can use the grid settings to position this line. The length of the line and the exact position

of its end points are not important since it is only going to be used to define a rotation axis.

8.

Select Revolvefrom the 3D Features Toolbar.

9. In the Details View, click next to Base Objectand then click on the name of the plane that you have just

created (Plane4) in the Tree View. Click Applyin the Details View.

10. In the Details View, click next to Axisand then click on the name of the sketch that you have just created

(Sketch4) in the Tree View. Click Applyin the Details View.

11. Set Angleto 60degrees.

12.

Click on Generateto create the revolve.

One more operation is needed to add another straight section of pipe to the outlet. This follows a very similar

procedure to the one that you have just used to create the first extension.

1.

Create a new plane by using the New Plane ( ) button on the Active Plane/Sketch Toolbar, which is

located above the Model View.

2. In the Details View, set Typeto be From Faceand Subtypeto be Outline Plane.

3. In the Details View, click in the box next to Base Face. There will now be two buttons, Applyand Cancel

and this means that you are ready to select the face from the Model View.

4. In the Model View, click on the circular face at the end of the newly revolved pipe section, which is in

the position with the lowest value of the Z-coordinate.


Section 2: Geometry Modification


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5.


6.

Select Extrudefrom the 3D Features Toolbar.

7. In the Details View, click next to Base Objectand then click on the name of the plane that you have just

created (Plane5) in the Tree View. Click Applyin the Details View.

8. Set Depthto 2m.9.

Click on Generateto create the extrude.

3. Updating the Geometry in CFX-Mesh

In this section you will make CFX-Mesh use the new geometry.

1. At the top of the ANSYS Workbench window, you should be able to see three tabs: StaticMixer [Project],

StaticMixer [DesignModeler]and StaticMixer [CFX-Mesh]. Click on StaticMixer [CFX-Mesh]to return

to the CFX-Mesh setup.

Look closely at the Tree View. You should be able to see that many of the settings, including the top item

(Model), have a green tick status symbol next to them, which means that the setup is completely valid. There

are no yellow ticks and no red marks which indicate potential problems or an invalid setup. Any Preview Groups

will have either a green tick ( ) or a green tick with a yellow flash ( ). In each case the green tick indicates

that the setup is completely valid. The addition of the yellow flash indicates that the mesh which is displayed

when you click on that Preview Group's name may not be up-to-date with the latest mesh settings i.e. you may

have modified a setting since you last generated this surface mesh.

1. Right-click over Geometryin the Tree View. Select Update Geometryand click on Yeson the popup

message to continue with the update.

The Model View will refresh to show the new geometry, with the smaller radius pipes and the longer outlet. Also,

the Tree View will be updated to account for the fact that whilst most geometry faces which were originally

present are still there, one no longer exists (the original end of the outlet pipe) and there are some new ones

(the sides and end of the new section of pipe).

1. Notice that the Tree View now shows that you have an invalid setup: various items show red exclamation

marks ( ). The problem is that the specification for the 2D Composite Region out is invalid since the

face it was applied to no longer exists.




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2. Click on outin the Tree View. Select the circular face at the bottom of the mixer vessel, with the lowest

value of the Z-coordinate.


The model setup is now valid - the red status symbols have all gone from the Tree View.

When you do a Geometry Update, any new faces are automatically added to the Default Preview Group and to

the Default 2D Region. This means that you do not need to update Inflated Boundary 1to include any newfaces because it was set up to use the Default 2D Region as its location and the new faces will have been auto-

matically added to this region.

Sometimes when you do a Geometry Update, you will find that one or more yellow tick marks appear in the Tree

View. This means that one or more faces was automatically removed from the corresponding meshing features

as a result of the Geometry Update, because those faces no longer exist in the new geometry. The setup is still

valid, however, because there is still at least one valid face used for that meshing feature. It is recommended

that if you see yellow tick marks in your Tree View, you should check that the locations for the corresponding

features are what you expect.

The geometry has been successfully updated and the CFX-Mesh setup is ready to re-mesh. At this point you

could create a new surface mesh or volume mesh. However, note that the CFX-5 example expects to use theoriginal geometry, so you should ensure that you don't overwrite the original GTM File when creating the volume

mesh.

1. Select File>Saveto save the CFX-Mesh database.

If you want to continue by working through the CFX-5 example Tutorial 2: Flow in a Static Mixer (Refined Mesh)

using the newly-generated mesh, and have CFX-5.7.1 in ANSYS Workbench installed on your machine, then follow

these steps:

1. On the Project Page, a new entry will have appeared when you generated the file: Advanced CFD. Unde

this entry, double-click on StaticMixerRefMesh.gtmto open up CFX-Pre.

2. Once CFX-Pre has opened, choose File>Save Simulation As...to save the simulation as StaticMixerRef

3. Work through the CFX-5.7.1 tutorial, missing out the instructions in the sections Creating a New Simu

lation and Importing a Mesh.

If you do not have CFX-5.7.1 in ANSYS Workbench installed or do not want to work through the CFX-5 example

then:

1. Exit from ANSYS Workbench by selecting File>Exit. Choose to save all highlighted files.


Section 3: Updating the Geometry in CFX-Mesh


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Tutorial 3: Process Injection Mixing Pipe

This example shows how to create a simple pipe junction, using Sweep to create the pipe profile. The following

geometry and meshing features are illustrated:

Face Spacing, for refining the mesh on a particular face;

Inflation; and

full surface mesh generation, to preview the full surface mesh.

If you want to skip the geometry creation part of the tutorial, then see the instructions in Introduction to theCFX-Mesh Tutorials.

1. Geometry Creation

Creating the Project

1. Open ANSYS Workbench, create a new empty project, and save it as InjectMixer.wbdb. If you need to

refer to the instructions in the Geometry Creation section of the Static Mixer tutorialfor more details on

how to do this.

2. Choose New Geometryto open DesignModeler, and specify the units as meters.

Creating the Main Pipe

To create the main pipe, you will use the Sweep operation. Sweep requires the use of two sketches: one defines

the profile to be swept (in this case, a circle) and the other defines the path through which the profile is swept.

The profile will be created first.



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1. Create a new plane as follows. Select the XYPlanein the Tree View and then click on the New Plane

icon ( ) from the Active Plane/Sketch Toolbar, near the top of the ANSYS Workbench window.

Clicking on XYPlanefirst ensures that the new plane is based on the XYPlane.

2. In the Details View, set Transform 1 (RMB)to Offset Z, and set the Valueof the offset to -4m.

3.


4. Create a new sketch as follows. Select Plane4in the Tree View and then click on the New Sketchicon

( ) from the Active Plane/Sketch Toolbar, near the top of the ANSYS Workbench window. Clicking

on the plane first ensures that the new sketch is based on Plane4.

5. Use Gridfrom the Settings Toolbox of the Sketching tab to set Show in 2Dand Snapto ON.

6. Set Major Grid Spacingto 1.0m and Minor-Steps per Majorto 2.

7. Zoom in to the center of the grid, so that you can see the gridlines clearly. You can do this by dragging

a box over the desired viewing area with the right mouse button held down.

8. Use Circlefrom the Draw Toolbox of the Sketching tab to draw a circle of radius 0.5 m, centered on X =

0 m, Y = -2 m. The grid settings you have just set up will help you to position the circle and set its radiuscorrectly.

Now create the path:

1.

Create a new sketch ( ) based on the YZPlane: as before, make the YZPlane active first by clicking

on it, and then use the New Sketchicon to create the sketch based upon it.

2. Use Gridfrom the Settings Toolbox of the Sketching tab to set Show in 2Dand Snapto ON.

3. Set Major Grid Spacingto 1.0m and Minor-Steps per Majorto 2.

4. Use Linefrom the Draw Toolbox of the Sketching tab to draw two straight lines on the sketch, as shown

in the picture below.5. Click on Arc by Centerfrom the Draw Toolbox, and click once on the origin (center of the Arc shown in

the picture below). Now select one of the end points of the arc, and then move the mouse round to the

other end point and click on it to draw the quarter-circle. If the wrong part of the arc is drawn (i.e. a 270

degree segment instead of a 90 segment) then click on Undo(from the Undo/Redo Toolbar at the top

of the ANSYS Workbench window) and try again, making sure that after you click on the first end point,

you move the mouse in the correct direction for the arc that is to be drawn.

Tutorial 3: Process Injection Mixing Pipe



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Now make the pipe itself.

1.

Select Sweepfrom the 3D Features Toolbar.

2. Set the Profileto be Sketch1: click on Sketch1in the Tree View and then click on Applyin the Details

View at the bottom-left of the screen.

3. Set the Pathto Sketch2: click on the Not selectedtext next to Path, click on Sketch2in the Tree View

and then click on Apply.

4.

Click on Generateto create the pipe.

Creating the Side Pipe

1.

Create a new plane ( ), based on the ZXPlane: as before, make the ZXPlane active first by clicking on

it, and then use the New Planeicon to create the plane based upon it.

2. In the Details View, set Transform 1to Offset Global Z, and set the Valueof the

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