Meshing a mixing elbow for a flow analysis

Summary: This example demonstrates how to mesh a mixing elbow for a flow analysis.

Objective

This example meshes a mixing elbow with polyhedral elements and wall boundary layer refinement. It uses several meshing utilities available in the lucid class for convenience and ease.

Procedure

• Launch Ansys Prime Server and instantiate meshing utilities from the lucid class.

• Import the geometry and create face zones from labels imported from the geometry.

• Surface mesh geometry with curvature sizing.

• Volume mesh with polyhedral elements and boundary layer refinement.

• Print statistics on the generated mesh.

• Write a CAS file for use in the Fluent solver.

• Exit the PyPrimeMesh session.

Launch Ansys Prime Server

Import all necessary modules. Launch an instance of Ansys Prime Server. Connect the PyPrimeMesh client and get the model. Instantiate meshing utilities from the lucid class.

import os
import tempfile

from ansys.meshing import prime
from ansys.meshing.prime.graphics import Graphics

prime_client = prime.launch_prime()
model = prime_client.model
mesh_util = prime.lucid.Mesh(model=model)

Import geometry

Download the elbow geometry (FMD) file exported by SpaceClaim. Import the geometry. Create face zones from labels imported from the geometry for use in Fluent solver.

# For Windows OS users, scdoc is also available:
# mixing_elbow = prime.examples.download_elbow_scdoc()

mixing_elbow = prime.examples.download_elbow_fmd()

mesh_util.read(file_name=mixing_elbow)
mesh_util.create_zones_from_labels("inlet,outlet")

Surface mesh

Surface mesh the geometry setting minimum and maximum sizing to use for curvature refinement.

mesh_util.surface_mesh(min_size=5, max_size=20)

Volume mesh

Volume mesh with polyhedral elements and boundary layer refinement. Fill the volume with polyhedral and prism mesh specifying the location and number of layers for prisms. Use expressions to define the surfaces to have prisms grown where * !inlet !outlet states all not inlet or outlet.

mesh_util.volume_mesh(
    volume_fill_type=prime.VolumeFillType.POLY,
    prism_surface_expression="* !inlet !outlet",
    prism_layers=3,
)

# Display the mesh
display = Graphics(model=model)
display()

Print mesh statistics

# Get meshed part
part = model.get_part_by_name("flow_volume")

# Get statistics on the mesh
part_summary_res = part.get_summary(prime.PartSummaryParams(model=model))

# Get element quality on all parts in the model
search = prime.VolumeSearch(model=model)
params = prime.VolumeQualitySummaryParams(
    model=model,
    scope=prime.ScopeDefinition(model=model, part_expression="*"),
    cell_quality_measures=[prime.CellQualityMeasure.SKEWNESS],
    quality_limit=[0.95],
)
results = search.get_volume_quality_summary(params=params)

# Print statistics on meshed part
print(part_summary_res)
print("\nMaximum skewness: ", results.quality_results_part[0].max_quality)

message :
Part Name: flow_volume
Part ID: 2
    13 Topo Edges
    9 Topo Faces
    1 Topo Volumes

    0 Edge Zones
        Edge Zone Name(s) : []
    2 Face Zones
        Face Zone Name(s) : [inlet, outlet]
    1 Volume Zones
        Volume Zone Name(s) : [volume]

    2 Label(s)
        Names: [inlet, outlet]

    Bounding box (-203.2 -228.6 -50.8)
                 (203.2 203.2 50.8)

    Mesh Summary:
        23792 Nodes
        1953 Poly Faces
        0 Quad Faces
        0 Tri Faces
        1953 Faces
        7554 Poly Cells
        0 Hex Cells
        0 Prism Cells
        0 Pyramid Cells
        0 Tet Cells
        7554 Cells
    0 out of 9 TopoFaces are unmeshed

n_topo_edges :  13
n_topo_faces :  9
n_topo_volumes :  1
n_edge_zonelets :  0
n_face_zonelets :  0
n_cell_zonelets :  0
n_edge_zones :  0
n_face_zones :  2
n_volume_zones :  1
n_labels :  2
n_nodes :  23792
n_faces :  1953
n_cells :  7554
n_tri_faces :  0
n_poly_faces :  1953
n_quad_faces :  0
n_tet_cells :  0
n_pyra_cells :  0
n_prism_cells :  0
n_poly_cells :  7554
n_hex_cells :  0
n_unmeshed_topo_faces :  0

Maximum skewness:  0.693907

Write mesh

Write a CAS file for use in the Fluent solver.

with tempfile.TemporaryDirectory() as temp_folder:
    mesh_file = os.path.join(temp_folder, "mixing_elbow.cas")
    mesh_util.write(mesh_file)
    assert os.path.exists(mesh_file)
    print("\nExported file:\n", mesh_file)

Exported file:
 /tmp/tmpghao1mly/mixing_elbow.cas

Exit PyPrimeMesh

prime_client.exit()