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Meshing a Pipe T-Section for Structural Thermal and Fluid Flow#
Summary: This example demonstrates how to mesh a pipe T-section for both fluid and structural thermal simulation.
Objective#
In this example, you can mesh the solids of a pipe T-section for a structural thermal analysis using tetrahedral elements and use the wrapper to extract the fluid domain and mesh using polyhedral cells with prismatic boundary layers.
Thermal structural and fluid flow meshes#
Procedure#
Launch Ansys Prime Server instance and connect PyPrimeMesh client.
Read CAD geometry.
Mesh for structural thermal analysis.
Write mesh for structural thermal analysis.
Extract fluid by wrapping.
Mesh with polyhedral and prisms.
Write mesh for fluid simulation.
Launch Ansys Prime Server#
. Import all necessary modules.
# . Launch Ansys Prime Server instance and connect client.
# . Get the client model and instantiate meshing utilities from lucid class.
import os
import tempfile
import ansys.meshing.prime.graphics as graphics
from ansys.meshing import prime
from ansys.meshing.prime import lucid
prime_client = prime.launch_prime()
model = prime_client.model
mesh_util = lucid.Mesh(model)
Read CAD Geometry#
. Download example FMD geometry file.
# FMD format is exported from SpaceClaim and is compatible with Linux.
# . Read and display the geometry file.
# The file contains several unmeshed parts as you would get after you imported from CAD.
file_name = prime.examples.download_pipe_tee_fmd()
mesh_util.read(file_name)
display = graphics.Graphics(model)
display()
print(model)
Part Summary:
Part Name: solid_coupling_out
Part ID: 2
18 Topo Edges
12 Topo Faces
1 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
0 Face Zones
Face Zone Name(s) : []
1 Volume Zones
Volume Zone Name(s) : [solid_coupling_out]
1 Label(s)
Names: [out]
Bounding box (-127 -360.99 -127)
(127 -184.15 127)
Part Name: solid_coupling_in1
Part ID: 3
18 Topo Edges
12 Topo Faces
1 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
0 Face Zones
Face Zone Name(s) : []
1 Volume Zones
Volume Zone Name(s) : [solid_coupling_in1]
1 Label(s)
Names: [in1]
Bounding box (-127 184.15 -127)
(127 356.616 127)
Part Name: solid_tee
Part ID: 4
50 Topo Edges
31 Topo Faces
1 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
0 Face Zones
Face Zone Name(s) : []
1 Volume Zones
Volume Zone Name(s) : [solid_tee]
0 Label(s)
Names: []
Bounding box (-127 -184.15 -127)
(127 184.15 203.2)
Part Name: solid_coupling_in2
Part ID: 5
18 Topo Edges
12 Topo Faces
1 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
0 Face Zones
Face Zone Name(s) : []
1 Volume Zones
Volume Zone Name(s) : [solid_coupling_in2]
1 Label(s)
Names: [in2]
Bounding box (-95.25 -95.25 203.2)
(95.25 95.25 374.65)
Part Name: cap_out
Part ID: 6
1 Topo Edges
1 Topo Faces
0 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
1 Face Zones
Face Zone Name(s) : [cap_out]
0 Volume Zones
Volume Zone Name(s) : []
1 Label(s)
Names: [outlet_main]
Bounding box (-76.2 -360.99 -76.2)
(76.2 -360.99 76.2)
Part Name: cap_in2
Part ID: 7
1 Topo Edges
1 Topo Faces
0 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
1 Face Zones
Face Zone Name(s) : [cap_in2]
0 Volume Zones
Volume Zone Name(s) : []
1 Label(s)
Names: [in2_inlet]
Bounding box (-51.308 -51.308 374.65)
(51.308 51.308 374.65)
Part Name: cap_in1
Part ID: 8
1 Topo Edges
1 Topo Faces
0 Topo Volumes
0 Edge Zones
Edge Zone Name(s) : []
1 Face Zones
Face Zone Name(s) : [cap_in1]
0 Volume Zones
Volume Zone Name(s) : []
1 Label(s)
Names: [in1_inlet]
Bounding box (-76.2 356.616 -76.2)
(76.2 356.616 76.2)
Mesh for Structural#
. Surface mesh using curvature sizing.
# . Volume mesh with tetrahedral elements.
# . Delete unwanted capping surface geometries by deleting
# parts that do not have any volume zones.
# . Display structural thermal mesh ready for export.
mesh_util.surface_mesh(min_size=2.5, max_size=10)
mesh_util.volume_mesh()
toDelete = [part.id for part in model.parts if not part.get_volume_zones()]
if toDelete:
model.delete_parts(toDelete)
display = graphics.Graphics(model)
display()
Write Structural Mesh#
Labels are exported to CDB as collections for applying load boundary conditions in the solver.
with tempfile.TemporaryDirectory() as temp_folder:
structural_mesh = os.path.join(temp_folder, "pipe_tee.cdb")
mesh_util.write(structural_mesh)
print("\nExported Structural Mesh: ", structural_mesh)
Exported Structural Mesh: /tmp/tmpwhb0wg5g/pipe_tee.cdb
Extract Fluid by Wrapping#
You can deal with the small internal diameter change between flanges in several ways:
Connect the geometry to extract a volume and refine the mesh around this detail to capture.
Modify the geometry to remove the feature.
Wrap to extract the internal flow volume and walk over the feature.
Here, you will choose to wrap and walk over these features.
. Read in the geometry again.
# . Use a constant size wrap to walk over the diameter change
# feature and extract the largest internal volume as the fluid.
# By default, the wrap uses all parts as input and delete the input
# geometry after wrapping unless keep_input is set as True.
# When displaying, you can avoid displaying unnecessary edge zones.
mesh_util.read(file_name)
wrap = mesh_util.wrap(min_size=6, region_extract=prime.WrapRegion.LARGESTINTERNAL)
print(model)
display()
Part Summary:
Part Name: __wrap__
Part ID: 9
1 Edge Zonelets
8 Face Zonelets
0 Cell Zonelets
0 Edge Zones
Edge Zone Name(s) : []
3 Face Zones
Face Zone Name(s) : [cap_out, cap_in2, cap_in1]
1 Volume Zones
Volume Zone Name(s) : [unreferenced]
13 Label(s)
Names: [___geom_features___, __extracted__features__, cap_in1, cap_in2, cap_out, in1_inlet, in2_inlet, outlet_main, solid_coupling_in1, solid_coupling_in2, solid_coupling_out, solid_tee, unreferenced]
Bounding box (-127 -360.99 -126.996)
(126.909 356.616 374.65)
Volume Mesh Fluid#
. Create zones for each label to be used for boundary conditions definitions.
# . Volume mesh with prism polyhedral not growing prisms from inlets and outlets.
# . Visualize the generated volume mesh.
# You can clearly see the prism layers that were specified by the Prism control.
# set global sizing
params = prime.GlobalSizingParams(model, min=6, max=50)
model.set_global_sizing_params(params)
mesh_util.create_zones_from_labels("outlet_main,in1_inlet,in2_inlet")
mesh_util.volume_mesh(
prism_layers=5,
prism_surface_expression="* !*inlet* !*outlet*",
volume_fill_type=prime.VolumeFillType.POLY,
)
print(model)
display(update=True, scope=prime.ScopeDefinition(model=model, label_expression="* !*__*"))
Part Summary:
Part Name: __wrap__
Part ID: 9
1 Edge Zonelets
8 Face Zonelets
1 Cell Zonelets
0 Edge Zones
Edge Zone Name(s) : []
6 Face Zones
Face Zone Name(s) : [cap_out, cap_in2, cap_in1, in1_inlet, in2_inlet, outlet_main]
1 Volume Zones
Volume Zone Name(s) : [unreferenced]
13 Label(s)
Names: [___geom_features___, __extracted__features__, cap_in1, cap_in2, cap_out, in1_inlet, in2_inlet, outlet_main, solid_coupling_in1, solid_coupling_in2, solid_coupling_out, solid_tee, unreferenced]
Bounding box (-127 -360.99 -126.996)
(126.909 356.616 374.65)
Write Fluid Mesh#
Write a MSH file for the Fluent solver.
with tempfile.TemporaryDirectory() as temp_folder:
fluid_mesh = os.path.join(temp_folder, "pipe_tee.msh")
mesh_util.write(fluid_mesh)
assert os.path.exists(fluid_mesh)
print("\nExported Fluid Mesh: ", fluid_mesh)
Exported Fluid Mesh: /tmp/tmpbf0_locg/pipe_tee.msh
Exit PyPrimeMesh#
prime_client.exit()
Total running time of the script: ( 0 minutes 56.465 seconds)