Introduction to ANSYS Meshing - Mr-CFD · operation done during the transfer to the ANSYS Mesher. •It is recommended to carryout the ShareTopology operation in DM itself. With this

© 2011 ANSYS, Inc. June 13, 2013 1 Release 14.5

14. 0 Release

Introduction to ANSYS Meshing

Workshop 1 Selective Meshing


Goals

This workshop will illustrate the use of the Selective Meshing using the mesh worksheet.


Project Startup

Create the Project

• Drag and drop a Mesh component system into the Project Schematic .

• Right click on the Geometry cell (A2) and select Import Geometry>Browse.

• Locate the file “motor_model.x_t” in the Meshing Workshops Input Files folder and select it. The geometry cell will show a check mark indicating it is up to date.

• Double click on the Geometry Cell.


Set Units:

• In the Units menu set Millimeters

• Click 'Generate' to import the model in DesignModeler

Units


The model consists of three bodies (representing the fluid parts) and rest of the solid parts.

Note that the bodies do not form a single part. Each body is separate part.

Geometry Description


To create Conformal Mesh in Solid and Fluid bodies we need to define a single part for all the 17 bodies

• To create multibody part select all the bodies and right click and select ‘Form New Part’ option

• Defining the multibody part will create the Share Topology in between the bodies clubbed under the multibody part. It allows to create conformal mesh.

Define Multibody Part

After multibody part


• The feature 'Share Tpology' performs the “Share Topology” operation in the ANSYS DesignModeler application that is similar to the topology sharing operation done during the transfer to the ANSYS Mesher.

• It is recommended to carryout the ShareTopology operation in DM itself. With this feature, you will see the same model in the ANSYS DesignModeler application that you will see after transferring the model to the ANSYS Mesher .

• Using Share Topology within DM can help to narrow in on problems, and possibly fix them in DM.

Share Topology


Switch to ANSYS main window

• Save the project with appropriate name.

• Double click on the ‘Meshing’cell to open ANSYS mesher

Open ANSYS Mesher


Initial Mesh

1. Left click on the Mesh object and set the Physics preference to CFD and select the FLUENT solver

2. Change the default Global Sizing function values under Sizing menu and set them manually as shown in side image.


Initial mesh with minimal global meshing size controls and using automatic meshing.

Initial Mesh


By inserting the local mesh method we can create full hex mesh for the model. While specifying the mesh methods we need to specify the appropriate details as well.

Local Mesh Methods


Specify Multizone mesh method for bodies shown in the image

Local Mesh Method Details

Source faces from the top

Similarly at the bottom


Specify Multizone mesh method for bodies shown in the image


Source faces from the top

Similarly at the bottom



Faces from top and bottom

Faces from top and bottom


Local Mesh Sizes

Defining the local mesh methods may not be sufficient to get desired mesh refinement. Hence we will add some local mesh sizes to the bodies. Let us start with the first one. •Apply specified face size to the source faces of shown body.


Local Mesh Sizes

•We will add face sizing to the source faces of the cage bar bodies. As these bodies are in large number in model, we will use Named Selection tools for easier selection of repetitive source faces.


Defining Named Selection To define Named Selection for the faces of the Cage_bar bodies. Use Name Selection worksheet.

•Select any single source face of Cage bar body •Right Click and select the ‘Create Named Selection’ •Specify the name ‘bar_faces’ •Select the size as the filter criteria for faces. •Click OK to

•This will create a Named Selection of all the source faces of cage bar bodies


Local Mesh Sizes

•To add face sizing to the faces clubbed under ‘bar_faces’ insert a local sizing •Define scoping method as ‘Named Selection’. •Select the named selection from drop down list. •Specify the Element size of 1.7 mm


Local Mesh Sizes

Face sizing Source faces from the top and bottom.


Switch on the Mesh Worksheet recording, the green light turns red in recording mode.

Selective Meshing


Mesh the multiple bodies as shown in following sequence. This sequence will automatically reflect in the worksheet with named selections.

Selective Meshing

1 2 3


For better Mesh growth, you can replace the mesh method for bodies shown in side images to sweep.

Sweep Mesh Method

Present mesh with Multizone


As we have the meshing sequence already recorded. To remesh the only bodies which we are expecting to have improved mesh can be only meshed using worksheet.

• To do so right click on the first step and select ‘Generate Mesh Through This Step’

Re-meshing after modifications


Mesh after Sweep Mesh

Multizone Mesh Mesh with Sweep


To mesh rest of the bodies using sequence Uncheck the first step. Click on the Generate Mesh button to mesh only the rest of the unmeshed bodies.

Re-meshing after modifications


Thank you

Documents

Introduction to ANSYS Meshing - Mr-CFD · operation done during the transfer to the ANSYS Mesher. •It is recommended to carryout the ShareTopology operation in DM itself. With this