def make_mesh(a, b, pml_width=0.25, **kwargs):
from meshpy.geometry import GeometryBuilder, make_circle
geob = GeometryBuilder()
circle_centers = [(-1.5, 0), (1.5, 0)]
for cent in circle_centers:
geob.add_geometry(*make_circle(1, cent))
geob.wrap_in_box(1)
geob.wrap_in_box(pml_width)
mesh_mod = geob.mesher_module()
mi = mesh_mod.MeshInfo()
geob.set(mi)
mi.set_holes(circle_centers)
built_mi = mesh_mod.build(mi, **kwargs)
def boundary_tagger(fvi, el, fn, points):
return []
from grudge.mesh import make_conformal_mesh_ext
from grudge.mesh.element import Triangle
pts = np.asarray(built_mi.points, dtype=np.float64)
return make_conformal_mesh_ext(
pts, [Triangle(i, el, pts) for i, el in enumerate(built_mi.elements)],
boundary_tagger)
def make_squaremesh():
def round_trip_connect(seq):
result = []
for i in range(len(seq)):
result.append((i, (i + 1) % len(seq)))
return result
def needs_refinement(vertices, area):
x = sum(numpy.array(v) for v in vertices) / 3
max_area_volume = 0.7e-2 + 0.03 * (0.05 * x[1]**2 +
0.3 * min(x[0] + 1, 0)**2)
max_area_corners = 1e-3 + 0.001 * max(
la.norm(x - corner)**4 for corner in obstacle_corners)
return bool(area > 2.5 * min(max_area_volume, max_area_corners))
from meshpy.geometry import make_box
points, facets, _, _ = make_box((-0.5, -0.5), (0.5, 0.5))
obstacle_corners = points[:]
from meshpy.geometry import GeometryBuilder, Marker
profile_marker = Marker.FIRST_USER_MARKER
builder = GeometryBuilder()
builder.add_geometry(points=points,
facets=facets,
facet_markers=profile_marker)
points, facets, _, facet_markers = make_box((-16, -22), (25, 22))
builder.add_geometry(points=points,
facets=facets,
facet_markers=facet_markers)
from meshpy.triangle import MeshInfo, build
mi = MeshInfo()
builder.set(mi)
mi.set_holes([(0, 0)])
mesh = build(mi,
refinement_func=needs_refinement,
allow_boundary_steiner=True,
generate_faces=True)
print("%d elements" % len(mesh.elements))
from meshpy.triangle import write_gnuplot_mesh
write_gnuplot_mesh("mesh.dat", mesh)
fvi2fm = mesh.face_vertex_indices_to_face_marker
face_marker_to_tag = {
profile_marker: "noslip",
Marker.MINUS_X: "inflow",
Marker.PLUS_X: "outflow",
Marker.MINUS_Y: "inflow",
Marker.PLUS_Y: "inflow"
}
def bdry_tagger(fvi, el, fn, all_v):
face_marker = fvi2fm[fvi]
return [face_marker_to_tag[face_marker]]
from grudge.mesh import make_conformal_mesh_ext
vertices = numpy.asarray(mesh.points, dtype=float, order="C")
from grudge.mesh.element import Triangle
return make_conformal_mesh_ext(vertices, [
Triangle(i, el_idx, vertices) for i, el_idx in enumerate(mesh.elements)
], bdry_tagger)
def make_nacamesh():
def round_trip_connect(seq):
result = []
for i in range(len(seq)):
result.append((i, (i + 1) % len(seq)))
return result
pt_back = numpy.array([1, 0])
#def max_area(pt):
#max_area_front = 1e-2*la.norm(pt)**2 + 1e-5
#max_area_back = 1e-2*la.norm(pt-pt_back)**2 + 1e-4
#return min(max_area_front, max_area_back)
def max_area(pt):
x = pt[0]
if x < 0:
return 1e-2 * la.norm(pt)**2 + 1e-5
elif x > 1:
return 1e-2 * la.norm(pt - pt_back)**2 + 1e-5
else:
return 1e-2 * pt[1]**2 + 1e-5
def needs_refinement(vertices, area):
barycenter = sum(numpy.array(v) for v in vertices) / 3
return bool(area > max_area(barycenter))
from meshpy.naca import get_naca_points
points = get_naca_points(naca_digits="2412", number_of_points=80)
from meshpy.geometry import GeometryBuilder, Marker
from meshpy.triangle import write_gnuplot_mesh
profile_marker = Marker.FIRST_USER_MARKER
builder = GeometryBuilder()
builder.add_geometry(points=points,
facets=round_trip_connect(points),
facet_markers=profile_marker)
builder.wrap_in_box(4, (10, 8))
from meshpy.triangle import MeshInfo, build
mi = MeshInfo()
builder.set(mi)
mi.set_holes([builder.center()])
mesh = build(
mi,
refinement_func=needs_refinement,
#allow_boundary_steiner=False,
generate_faces=True)
write_gnuplot_mesh("mesh.dat", mesh)
print("%d elements" % len(mesh.elements))
fvi2fm = mesh.face_vertex_indices_to_face_marker
face_marker_to_tag = {
profile_marker: "noslip",
Marker.MINUS_X: "inflow",
Marker.PLUS_X: "outflow",
Marker.MINUS_Y: "inflow",
Marker.PLUS_Y: "inflow"
#Marker.MINUS_Y: "minus_y",
#Marker.PLUS_Y: "plus_y"
}
def bdry_tagger(fvi, el, fn, all_v):
face_marker = fvi2fm[fvi]
return [face_marker_to_tag[face_marker]]
from grudge.mesh import make_conformal_mesh_ext
vertices = numpy.asarray(mesh.points, order="C")
from grudge.mesh.element import Triangle
return make_conformal_mesh_ext(
vertices,
[
Triangle(i, el_idx, vertices)
for i, el_idx in enumerate(mesh.elements)
],
bdry_tagger,
#periodicity=[None, ("minus_y", "plus_y")]
)