example.py

""" example of ofblockmeshdicthelper
try to generate wedged pype object shown at
https://openfoamwiki.net/index.php/Main_ContribExamples/AxiSymmetric
"""

from __future__ import unicode_literals, print_function, division

import math

from ofblockmeshdicthelper import BlockMeshDict, Vertex, SimpleGrading

wedgedegree = 5.0

# geometries
radius_x = 0.19
length_z = 1.1

# prepare ofblockmeshdicthelper.BlockMeshDict instance to
# gather vertices, blocks, faces and boundaries.
bmd = BlockMeshDict()

#
bmd.set_metric('m')

# base vertices which are rotated +- 2.5 degrees
basevs = [
    Vertex(0, 0, 0, 'v0'),
    Vertex(radius_x, 0, 0, 'v1'),
    Vertex(radius_x, 0, length_z, 'v2'),
    Vertex(0, 0, length_z, 'v3')]

# rotate wedgedegree/2 around z axis
# rotated vertices are named with '-y' or '+y' suffix.
# these verteces are added to BlockMeshDict instence to be referred
# by following blocks and faces...
cosd = math.cos(math.radians(wedgedegree/2.0))
sind = math.sin(math.radians(wedgedegree/2.0))
for v in basevs:
    bmd.add_vertex(v.x*cosd, -v.x*sind, v.z, v.name+'-y')
    bmd.add_vertex(v.x*cosd,  v.x*sind, v.z, v.name+'+y')

# v0+y and v3+y have same coordinate as v0-y and v3-y, respectively.
bmd.reduce_vertex('v0-y', 'v0+y')
bmd.reduce_vertex('v3-y', 'v3+y')


# utility to to generate vertex names
def vnamegen(x0z0, x1z0, x1z1, x0z1):
    return (x0z0+'-y', x1z0+'-y', x1z0+'+y', x0z0+'+y',
            x0z1+'-y', x1z1+'-y', x1z1+'+y', x0z1+'+y')

# Noted that 'v0+y' and 'v3+y' are still valid
b0 = bmd.add_hexblock(vnamegen('v0', 'v1', 'v2', 'v3'),
                      (19, 1, 300), 'b0',
                      SimpleGrading(0.1,
                                    ((0.2, 0.3, 4),  # multi-grading for > OF2.4
                                     (0.6, 0.4, 1),
                                     (0.2, 0.3, 1/4)),
                                    1))

# face element of block can be generated by Block.face method
bmd.add_boundary('wedge', 'front', [b0.face('ym')])
bmd.add_boundary('wedge', 'back', [b0.face('yp')])
bmd.add_boundary('wall', 'tankWall', [b0.face('xp')])
bmd.add_boundary('patch', 'inlet', [b0.face('zm')])
bmd.add_boundary('patch', 'outlet', [b0.face('zp')])
bmd.add_boundary('empty', 'axis', [b0.face('xm')])

# prepare for output
bmd.assign_vertexid()
# output
print(bmd.format())