def test_quad_mesh_3d(mesh_name, order=3, visualize=False):
if mesh_name == "ball":
from meshmode.mesh.io import ScriptWithFilesSource
script = ScriptWithFilesSource(
"""
Merge "ball-radius-1.step";
// Mesh.CharacteristicLengthMax = 0.1;
Mesh.RecombineAll = 1;
Mesh.Recombine3DAll = 1;
Mesh.Recombine3DLevel = 2;
Mesh.Algorithm = 8;
Mesh.Algorithm3D = 8;
Mesh 3;
Save "output.msh";
""", ["ball-radius-1.step"])
with open("ball-quad.geo", "w") as f:
f.write(script.source)
elif mesh_name == "cube":
from meshmode.mesh.io import ScriptSource
script = ScriptSource(
"""
SetFactory("OpenCASCADE");
Box(1) = {0, 0, 0, 1, 1, 1};
Transfinite Line "*" = 8;
Transfinite Surface "*";
Transfinite Volume "*";
Mesh.RecombineAll = 1;
Mesh.Recombine3DAll = 1;
Mesh.Recombine3DLevel = 2;
""", "geo")
else:
raise ValueError(f"unknown mesh name: '{mesh_name}'")
np.set_printoptions(linewidth=200)
from meshmode.mesh.io import generate_gmsh
logger.info("BEGIN GEN")
mesh = generate_gmsh(script, 3, order=order, target_unit="MM")
logger.info("END GEN")
if visualize:
from meshmode.mesh.visualization import write_vertex_vtk_file
write_vertex_vtk_file(mesh,
f"quad_mesh_3d_{mesh_name}.vtu",
overwrite=True)
def test_quad_mesh_2d():
from meshmode.mesh.io import generate_gmsh, ScriptWithFilesSource
print("BEGIN GEN")
mesh = generate_gmsh(
ScriptWithFilesSource(
"""
Merge "blob-2d.step";
Mesh.CharacteristicLengthMax = 0.05;
Recombine Surface "*" = 0.0001;
Mesh 2;
Save "output.msh";
""", ["blob-2d.step"]),
force_ambient_dim=2,
)
print("END GEN")
print(mesh.nelements)
def test_quad_mesh_2d(ambient_dim, filename, visualize=False):
from meshmode.mesh.io import generate_gmsh, ScriptWithFilesSource
logger.info("BEGIN GEN")
mesh = generate_gmsh(
ScriptWithFilesSource(
f"""
Merge "{filename}";
Mesh.CharacteristicLengthMax = 0.05;
Recombine Surface "*" = 0.0001;
Mesh 2;
Save "output.msh";
""", [filename]),
order=1,
force_ambient_dim=ambient_dim,
target_unit="MM",
)
logger.info("END GEN")
logger.info("nelements: %d", mesh.nelements)
groups = []
for grp in mesh.groups:
if not isinstance(grp, TensorProductElementGroup):
# NOTE: gmsh isn't guaranteed to recombine all elements, so we
# could still have some simplices sitting around, so skip them
groups.append(grp.copy())
continue
g = mgen.make_group_from_vertices(mesh.vertices,
grp.vertex_indices,
grp.order,
group_cls=TensorProductElementGroup)
assert g.nodes.shape == (mesh.ambient_dim, grp.nelements,
grp.nunit_nodes)
groups.append(g)
mesh_from_vertices = Mesh(mesh.vertices, groups=groups, is_conforming=True)
if visualize:
from meshmode.mesh.visualization import write_vertex_vtk_file
write_vertex_vtk_file(mesh, "quad_mesh_2d_orig.vtu")
write_vertex_vtk_file(mesh_from_vertices, "quad_mesh_2d_groups.vtu")
def no_test_quad_mesh_3d():
from meshmode.mesh.io import generate_gmsh, ScriptWithFilesSource
print("BEGIN GEN")
mesh = generate_gmsh(
ScriptWithFilesSource(
"""
Merge "ball-radius-1.step";
// Mesh.CharacteristicLengthMax = 0.1;
Mesh.RecombineAll=1;
Mesh.Recombine3DAll=1;
Mesh.Algorithm = 8;
Mesh.Algorithm3D = 9;
// Mesh.Smoothing = 0;
// Mesh.ElementOrder = 3;
Mesh 3;
Save "output.msh";
""", ["ball-radius-1.step"]), )
print("END GEN")
print(mesh.nelements)
def get_mesh(self, resolution, target_order):
from pytools import download_from_web_if_not_present
download_from_web_if_not_present(
"https://raw.githubusercontent.com/inducer/geometries/a869fc3/"
"surface-3d/betterplane.brep")
from meshmode.mesh.io import generate_gmsh, ScriptWithFilesSource
mesh = generate_gmsh(
ScriptWithFilesSource(
"""
Merge "betterplane.brep";
Mesh.CharacteristicLengthMax = %(lcmax)f;
Mesh.ElementOrder = 2;
Mesh.CharacteristicLengthExtendFromBoundary = 0;
// 2D mesh optimization
// Mesh.Lloyd = 1;
l_superfine() = Unique(Abs(Boundary{ Surface{
27, 25, 17, 13, 18 }; }));
l_fine() = Unique(Abs(Boundary{ Surface{ 2, 6, 7}; }));
l_coarse() = Unique(Abs(Boundary{ Surface{ 14, 16 }; }));
// p() = Unique(Abs(Boundary{ Line{l_fine()}; }));
// Characteristic Length{p()} = 0.05;
Field[1] = Attractor;
Field[1].NNodesByEdge = 100;
Field[1].EdgesList = {l_superfine()};
Field[2] = Threshold;
Field[2].IField = 1;
Field[2].LcMin = 0.075;
Field[2].LcMax = %(lcmax)f;
Field[2].DistMin = 0.1;
Field[2].DistMax = 0.4;
Field[3] = Attractor;
Field[3].NNodesByEdge = 100;
Field[3].EdgesList = {l_fine()};
Field[4] = Threshold;
Field[4].IField = 3;
Field[4].LcMin = 0.1;
Field[4].LcMax = %(lcmax)f;
Field[4].DistMin = 0.15;
Field[4].DistMax = 0.4;
Field[5] = Attractor;
Field[5].NNodesByEdge = 100;
Field[5].EdgesList = {l_coarse()};
Field[6] = Threshold;
Field[6].IField = 5;
Field[6].LcMin = 0.15;
Field[6].LcMax = %(lcmax)f;
Field[6].DistMin = 0.2;
Field[6].DistMax = 0.4;
Field[7] = Min;
Field[7].FieldsList = {2, 4, 6};
Background Field = 7;
""" % {
"lcmax": resolution,
}, ["betterplane.brep"]), 2)
# Flip elements--gmsh generates inside-out geometry.
from meshmode.mesh.processing import perform_flips
return perform_flips(mesh, np.ones(mesh.nelements))
def get_pseudo_y0_mesh():
"""Generate or import a grid using `gmsh`.
Input required:
data/pseudoY0.brep (for mesh gen)
-or-
data/pseudoY0.msh (read existing mesh)
This routine will generate a new grid if it does
not find the grid file (data/pseudoY0.msh), but
note that if the grid is generated in millimeters,
then the solution initialization and BCs need to be
adjusted or the grid needs to be scaled up to meters
before being used with the current main driver in this
example.
"""
from meshmode.mesh.io import (
read_gmsh,
generate_gmsh,
ScriptWithFilesSource
)
import os
if os.path.exists("data/pseudoY1nozzle.msh") is False:
mesh = generate_gmsh(
ScriptWithFilesSource("""
Merge "data/pseudoY1nozzle.brep";
Mesh.CharacteristicLengthMin = 1;
Mesh.CharacteristicLengthMax = 10;
Mesh.ElementOrder = 2;
Mesh.CharacteristicLengthExtendFromBoundary = 0;
// Inside and end surfaces of nozzle/scramjet
Field[1] = Distance;
Field[1].NNodesByEdge = 100;
Field[1].FacesList = {5,7,8,9,10};
Field[2] = Threshold;
Field[2].IField = 1;
Field[2].LcMin = 1;
Field[2].LcMax = 10;
Field[2].DistMin = 0;
Field[2].DistMax = 20;
// Edges separating surfaces with boundary layer
// refinement from those without
// (Seems to give a smoother transition)
Field[3] = Distance;
Field[3].NNodesByEdge = 100;
Field[3].EdgesList = {5,10,14,16};
Field[4] = Threshold;
Field[4].IField = 3;
Field[4].LcMin = 1;
Field[4].LcMax = 10;
Field[4].DistMin = 0;
Field[4].DistMax = 20;
// Min of the two sections above
Field[5] = Min;
Field[5].FieldsList = {2,4};
Background Field = 5;
""", ["data/pseudoY1nozzle.brep"]), 3, target_unit="MM")
else:
mesh = read_gmsh("data/pseudoY1nozzle.msh")
return mesh