1 Lab

1. Workshop 4.2 Tetra Meshing - Valve

14. 0 Release
Introduction to ANSYS
ICEM CFD
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

2. Set Working Directory

• Set working directory
– File > Change Working Dir…
– Choose Valve
– OK
• To Import The Geometry
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File -> Import Geometry ->
ParaSolid
Select: Valve.x_t using the
file browser and click Open
Set Units to Millimeter and
click Apply
© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

3. Build Topology

• Geometry > Repair Geometry >
Build Diagnostic Topology
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Accept all defaults
Tolerance of 0.1 is computed from
diagonal of bounding box
Click Apply
• Display the geometry
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© 2011 ANSYS, Inc.
May 6, 2026
Activate Surfaces by left mouse
clicking the check box in the
model tree
Right mouse click in the model
tree on Surfaces > Solid & Wire
Release 14.0

4. Create Parts

Break the Geometry into Parts
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Turn off Curves visibility to more easily pick surfaces
RMB on Parts and select Create Part from the pull down
The Create Part panel appears
Change the Part name to INLET
Accept the default selection method Create Part by Selection
Select the appropriate 3 inlet surfaces as shown below
Repeat the above steps for the other surface parts as shown
INLET
VALVESPHERE
OUTLET
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

5. Create Parts – Continued

Continue breaking the geometry into Parts
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Turn off the VALVESPHERE part in the Model tree. This will expose the Valve
Inside
Create a new Part, VALVE and add the 6 surfaces of the valve head to this Part
Separate parts makes it easier to visualize segments of the model by turning
parts on and off
Separate INLET and OUTLET Parts are essential to apply individual
boundary conditions. The BC’s are applied to the part names.
Note: the Parts are color matched with their names in the model tree
VALVE
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

6. Create Material Point

Tetra Octree will assign the volume elements to the part name
of the material point inside the closed collection of surfaces
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The material point must be inside the volume and not on a surface
Select Geometry > Create Body
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Right click on Surfaces > Wireframe in model tree
Enter FLUID_MAT as the Part name
Click on Material Point button
Select two screen locations so that the middle of these locations is
inside the model
Middle click to accept and then again to exit the function
Take note that Bodies appeared in the model tree
Rotate the geometry on the screen to ensure the material point is
inside the region to mesh
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© 2011 ANSYS, Inc.
May 6, 2026
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Release 14.0

7. Build Topology

• Remember that curves and points act as constraints to the
mesher, so let’s remove curves and points which are not at
hard angles
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Geometry > Repair Geometry > Build Diagnostic Topology
Default: Tolerance is auto-calculated as 0.1
Filter by angle: Turn on Filter points and Filter curves
Set Feature angle to 15
Default: Part name is set to Inherit Part
Accept other defaults and Click Apply
Many curves
are filtered out
Only essential feature
curves remain
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

8. Global Mesh Size

• Set the max volume element size in the entire mesh
• Mesh > Global Mesh Setup > Global Mesh Size
– Set Max element = 64
– Click Apply
– Turn on Display under Max element to see a one-icon
display of this size in the center of the model
• This is a very large element size but the mesh will
be controlled based on surface sizing performed in
the next step
– The initial surrounding octree mesh is seeded with
this size, so too small a max size will make meshing
take longer
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

9. Surface Mesh Size

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© 2011 ANSYS, Inc.
May 6, 2026
Set Surface Mesh Size
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Mesh -> Surface Mesh Setup
Click the Select surface(s) picker
The Select geometry popup tool bar appears, use the
Select All icon to select all the surfaces
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Set the Maximum size to 4
Click Apply
Right mouse click on Surfaces > Tetra Sizes in Model
tree to see a visual display of the sizes
Release 14.0

10. Curve Mesh Size

Go to Mesh -> Curve Mesh Set up
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© 2011 ANSYS, Inc.
May 6, 2026
Method -> General
Press the Select Curve(s) button
and select the
indicated curves
Set Maximum Size to 2
Set Tetra Width to 3
• Increases the radius of influence of this sizing
control (3 layers at size 2)
Click Apply
Display Curve Mesh Size
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First turn on Curves
in the model tree
RMB on Curves > Curve Tetra Sizes in tree
Release 14.0

11. Create Density Region

Create Density Box to locally control volume mesh size
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© 2011 ANSYS, Inc.
May 6, 2026
Surface and curve sizes only control mesh sizes on those
entities. Densities control mesh sizes within a volume.
Mesh -> Create Mesh Density
Set the Size to 2
Set the Type to Entity bounds
Use the Select geometry
picker
The Select geometry popup tool bar appears, use the
Select Items in a Part
Icon to select the ValveSphere
Part
Accept, then Apply
Release 14.0

12. Compute Mesh

• Select Mesh > Compute Mesh > Volume Mesh
– Set Mesh Method > Robust (Octree) (default)
– Click Compute
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

13. Cutplane View

The Surface Tetra Sizes affect
the mesh near the surface
Cutplane View
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RMB on Mesh > Cut Plane… > Manage Cut
Plane in the model tree
Change the Cut Plane Method to Middle X
Plane
Adjust the Fraction Value to display this
image (about 0.43)
Activate Volumes from the Mesh branch
The Curve Size and
width set to 3 affect
the mesh size within
at least three
elements of the
curves
The Density region
controls the max
element size
within the valve
sphere
The Global max size limits the largest element
possible, but it may not be reached
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© 2011 ANSYS, Inc.
May 6, 2026
Release 14.0

14. Check Mesh Quality

Check mesh quality
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© 2011 ANSYS, Inc.
May 6, 2026
Select Edit Mesh > Display Mesh Quality
• Set the Criterion to quality (default)
• Click Apply
Check the quality histogram. Smooth mesh if
needed
Save Project when satisfied with quality
– File > Save Project as…
• Enter Valve.prj
Release 14.0