doc/salome/examples/creating_meshes_ex06.py

   1 # Creating a hexahedral mesh on a cylinder.
   2 #
   3 # This example uses Partition to divide the cylinder into blocks, which is
   4 # a general approach. But for the case of cylinder there is a dedicated
   5 # command creating a blocked cylinder: geompy.MakeDividedCylinder()
   6
   7 import salome
   8 salome.salome_init()
   9 import GEOM
  10 from salome.geom import geomBuilder
  11 geompy = geomBuilder.New(salome.myStudy)
  12
  13 import SMESH, SALOMEDS
  14 from salome.smesh import smeshBuilder
  15 smesh =  smeshBuilder.New(salome.myStudy)
  16
  17 import math
  18
  19 # Parameters
  20 # ----------
  21
  22 radius =  50
  23 height = 200
  24
  25 # Build a cylinder
  26 # ----------------
  27
  28 base = geompy.MakeVertex(0, 0, 0)
  29 direction = geompy.MakeVectorDXDYDZ(0, 0, 1)
  30
  31 cylinder = geompy.MakeCylinder(base, direction, radius, height)
  32
  33 geompy.addToStudy(cylinder, "cylinder")
  34
  35 # Build blocks
  36 # ------------
  37
  38 size = radius/2.0
  39
  40 box_rot = geompy.MakeBox(-size, -size, 0,  +size, +size, height)
  41 box_axis = geompy.MakeLine(base, direction)
  42 box = geompy.MakeRotation(box_rot, box_axis, math.pi/4)
  43
  44 hole = geompy.MakeCut(cylinder, box)
  45
  46 plane_trim = 2000
  47
  48 plane_a = geompy.MakePlane(base, geompy.MakeVectorDXDYDZ(1, 0, 0), plane_trim)
  49 plane_b = geompy.MakePlane(base, geompy.MakeVectorDXDYDZ(0, 1, 0), plane_trim)
  50
  51 blocks_part = geompy.MakePartition([hole], [plane_a, plane_b], [], [], geompy.ShapeType["SOLID"])
  52 blocks_list = [box] + geompy.SubShapeAll(blocks_part, geompy.ShapeType["SOLID"])
  53 blocks_all = geompy.MakeCompound(blocks_list)
  54 blocks = geompy.MakeGlueFaces(blocks_all, 0.0001)
  55
  56 geompy.addToStudy(blocks, "cylinder:blocks")
  57
  58 # Build geometric groups
  59 # ----------------------
  60
  61 def group(name, shape, type, base=None, direction=None):
  62     t = geompy.ShapeType[type]
  63     g = geompy.CreateGroup(shape, t)
  64
  65     geompy.addToStudy(g, name)
  66     g.SetName(name)
  67
  68     if base!=None:
  69         l = geompy.GetShapesOnPlaneWithLocationIDs(shape, t, direction, base, GEOM.ST_ON)
  70         geompy.UnionIDs(g, l)
  71
  72     return g
  73
  74 group_a = group("baseA", blocks, "FACE", base, direction)
  75
  76 base_b  = geompy.MakeVertex(0, 0, height)
  77 group_b = group("baseB", blocks, "FACE", base_b, direction)
  78
  79 group_1 = group("limit", blocks, "SOLID")
  80 group_1_all = geompy.SubShapeAllIDs(blocks, geompy.ShapeType["SOLID"])
  81 geompy.UnionIDs(group_1, group_1_all)
  82 group_1_box = geompy.GetBlockNearPoint(blocks, base)
  83 geompy.DifferenceList(group_1, [group_1_box])
  84
  85 # Mesh the blocks with hexahedral
  86 # -------------------------------
  87
  88 smesh.SetCurrentStudy(salome.myStudy)
  89
  90 def discretize(x, y, z,  n, s=blocks):
  91     p = geompy.MakeVertex(x, y, z)
  92     e = geompy.GetEdgeNearPoint(s, p)
  93     a = hexa.Segment(e)
  94     a.NumberOfSegments(n)
  95     a.Propagation()
  96
  97 hexa = smesh.Mesh(blocks)
  98
  99 hexa_1d = hexa.Segment()
 100 hexa_1d.NumberOfSegments(1)
 101
 102 discretize(+radius        , +radius,        0,   5)
 103 discretize(-radius        , +radius,        0,   8)
 104 discretize((radius+size)/2,       0,        0,  10)
 105 discretize(        +radius,       0, height/2,  20)
 106
 107 hexa.Quadrangle()
 108 hexa.Hexahedron()
 109
 110 hexa.Compute()
 111
 112 hexa.Group(group_a)
 113 hexa.Group(group_b)
 114 hexa.Group(group_1)