def create_toy_mesh():
box = mshr.Box(dolfin.Point(-3, -1, -0.5), dolfin.Point(3, 1, 0.5))
c1 = mshr.Cylinder(dolfin.Point(0, 0, -2), dolfin.Point(0, 0, 2), 0.6, 0.6)
b1 = mshr.Box(dolfin.Point(-2.5, -0.5, -2), dolfin.Point(-1.5, 0.5, 2))
# "triangle"
t1 = mshr.Polygon([
dolfin.Point(2.5, -0.5, 0),
dolfin.Point(2.5, 0.5, 0),
dolfin.Point(1.5, -0.5, 0),
])
g3d = mshr.Extrude2D(t1, -2)
g3d = mshr.CSGTranslation(g3d, dolfin.Point(0, 0, 1))
m = mshr.generate_mesh(box - c1 - b1 - g3d, 40, "cgal")
return m.coordinates(), m.cells()
import mshr
import dolfin as dlf
radius = 0.5
height = 10.0
circ = mshr.Circle(dlf.Point(), radius, 100)
domain = mshr.Extrude2D(circ, height)
mesh = mshr.generate_mesh(domain, 200)
dlf.File('cylinder-mesh.xml.gz') << mesh
dlf.File('cylinder-mesh.pvd') << mesh
# Region IDs
ALL_ELSE = 0
INLET = 1
OUTLET = 2
NOSLIP = 3
class Boundary(dlf.SubDomain):
def inside(self, x, on_boundary):
return on_boundary
class Inlet(dlf.SubDomain):
def inside(self, x, on_boundary):
return abs(x[2]) < dlf.DOLFIN_EPS \
and on_boundary
class Outlet(dlf.SubDomain):
# Copyright (C) 2015 Benjamin Kehlet # # This file is part of mshr. # # mshr is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # mshr is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with mshr. If not, see <http://www.gnu.org/licenses/>. # This demo illustrates how a 2D geometry can be extruded to 3D. from dolfin import * import mshr g2d = mshr.Circle(Point(0, 0), 1.2) + mshr.Circle(Point(0, 1.2), 1.2) # Any simple 2D geometry can be extruded to 3D g3d = mshr.Extrude2D(g2d, .2) # The z "thickness" m = mshr.generate_mesh(g3d, 15) plot(m, interactive=True)