def test_boom_areas(self):
# problem 20.1 taken from Megson. Solution is given on the book
neutral_axis = (0, 1, 0)
# set up boom architecture
boom0 = boom.Boom(0, [0, 150], 1000, neutral_axis)
boom1 = boom.Boom(1, [500, 150], 50 * 8 + 30 * 8, neutral_axis)
boom2 = boom.Boom(2, [500, -150], 50 * 8 + 30 * 8, neutral_axis)
boom3 = boom.Boom(3, [0, -150], 1000, neutral_axis)
edge01 = edges.Edge([0, 1], 10, 500)
edge03 = edges.Edge([0, 3], 10, 300)
edge12 = edges.Edge([1, 2], 8, 300)
edge23 = edges.Edge([2, 3], 10, 500)
booms = [boom0, boom1, boom2, boom3]
edge_list = [edge01, edge03, edge12, edge23]
problem_20_1 = geometry.Geometry(4, booms, edge_list, [0.], 0.)
problem_20_1.construct_geometry()
# calculate boom area for each boom
for element in booms:
element.calculate_area(problem_20_1)
self.assertTrue(abs(boom0.area - 4000) < 1)
self.assertTrue(abs(boom0.area - boom3.area) < 0.01)
self.assertTrue(abs(boom1.area - 3540) < 1)
self.assertTrue(abs(boom1.area - boom2.area) < 0.01)
def test_areas_centroid_inertia(self):
# following the example on slide 43 of https://www.slideshare.net/scemd3/lec6aircraft-structural-idealisation-1
# set up boom architecture
neutral_axis = (0, 1, 0)
boom0 = boom.Boom(0, [-250, 150], 1000, neutral_axis)
boom1 = boom.Boom(1, [250, 150], 640, neutral_axis)
boom2 = boom.Boom(2, [250, -150], 640, neutral_axis)
boom3 = boom.Boom(3, [-250, -150], 1000, neutral_axis)
edge01 = edges.Edge([0, 1], 10, 500)
edge03 = edges.Edge([0, 3], 10, 300)
edge12 = edges.Edge([1, 2], 8, 300)
edge23 = edges.Edge([2, 3], 10, 500)
# calculate area for each boom
example_43 = geometry.Geometry(4, [boom0, boom1, boom2, boom3],
[edge01, edge03, edge12, edge23], [0.0],
0.)
example_43.construct_geometry()
for element in [boom0, boom1, boom2, boom3]:
element.calculate_area(example_43)
# test the boom areas
example_43.get_areas()
self.assertTrue(
abs(example_43.boom_areas[0] - example_43.boom_areas[3]) < 0.01
and abs(example_43.boom_areas[0] - 4000) < 0.01)
self.assertTrue(
abs(example_43.boom_areas[1] - example_43.boom_areas[1]) < 0.01
and abs(example_43.boom_areas[1] - 3540) < 0.01)
# test centroid
example_43.calc_centroid()
self.assertTrue(abs(abs(example_43.centroid[0]) - 15.25) < 0.1)
self.assertTrue(abs(abs(example_43.centroid[1]) - 0.0) < 0.1)
# test moments of inertia
example_43.moment_inertia_Izz()
example_43.moment_inertia_Iyy()
self.assertTrue(abs(example_43.Izz - 339300000) < 1)
self.assertTrue(abs(example_43.Iyy - 938992042.5) < 1)
self.assertTrue(abs(example_43.Izy) < 1)
def test_shear_flow_pure_torsion(self):
# this problem is a generic pure torsion problem
# initialise booms
neutral_axis = (0, 1, 0)
boom_list = []
boom0 = boom.Boom(0, [900, 250], 0.0, neutral_axis)
boom_list.append(boom0)
boom1 = boom.Boom(1, [900, -250], 0.0, neutral_axis)
boom_list.append(boom1)
boom2 = boom.Boom(2, [400, -250], 0.0, neutral_axis)
boom_list.append(boom2)
boom3 = boom.Boom(3, [0, -250], 0.0, neutral_axis)
boom_list.append(boom3)
boom4 = boom.Boom(4, [0, 250], 0.0, neutral_axis)
boom_list.append(boom4)
boom5 = boom.Boom(5, [400, 250], 0.0, neutral_axis)
boom_list.append(boom5)
# initialise edges
edge_list = []
edge01 = edges.Edge([0, 1], 4, 500)
edge_list.append(edge01)
edge12 = edges.Edge([1, 2], 4, 500)
edge_list.append(edge12)
edge23 = edges.Edge([2, 3], 2, 400)
edge_list.append(edge23)
edge34 = edges.Edge([3, 4], 2, 500)
edge_list.append(edge34)
edge45 = edges.Edge([4, 5], 2, 400)
edge_list.append(edge45)
edge50 = edges.Edge([5, 0], 4, 500)
edge_list.append(edge50)
edge52 = edges.Edge([5, 2], 3, 500)
edge_list.append(edge52)
# initialise geometry
problem_torsion = geometry.Geometry(6, boom_list, edge_list,
[400 * 500, 500**2], 27 * 10**3)
problem_torsion.cells = [[edge50, edge01, edge12, edge52],
[edge45, edge52, edge34, edge23]]
problem_torsion.construct_geometry()
# calculate torsion shear flows
problem_torsion_section = DiscreteSection.DiscreteSection(
neutral_axis, problem_torsion)
problem_torsion_section.calc_torsion_shear_flow(2.0329 * 10**9, edge52)
# verify twist rate
self.assertTrue(
abs(problem_torsion_section.twist_rate * 10**5 - 8.73) < 1)
def add_successor(self, succID, edgeID=None):
assert succID not in self.successors, "Vertex %d already has successor %d" % (
self.vertexID, succID)
e = edges.Edge(succID, edgeID)
self.successors[succID] = e
def add_predecessor(self, predID, edgeID=None):
assert predID not in self.predecessors, "Vertex %d already has predecessor %d" % (
self.vertexID, predID)
e = edges.Edge(predID, edgeID)
self.predecessors[predID] = e
def test_shear_flow_pure_shear0(self):
# following the problem 23.6 in Megson
# set up booms and edges
neutral_axis = (0, 1, 0)
boom0 = boom.Boom(0, [1092, 153], 0.0, neutral_axis)
boom1 = boom.Boom(1, [736, 153], 0.0, neutral_axis)
boom2 = boom.Boom(2, [380, 153], 0.0, neutral_axis)
boom3 = boom.Boom(3, [0, 153], 0.0, neutral_axis)
boom4 = boom.Boom(4, [0, -153], 0.0, neutral_axis)
boom5 = boom.Boom(5, [380, -153], 0.0, neutral_axis)
boom6 = boom.Boom(6, [736, -153], 0.0, neutral_axis)
boom7 = boom.Boom(7, [1092, -153], 0.0, neutral_axis)
boom_list = [boom0, boom1, boom2, boom3, boom4, boom5, boom6, boom7]
edge10 = edges.Edge([1, 0], 0.915, 356)
edge07 = edges.Edge([0, 7], 1.250, 306)
edge21 = edges.Edge([2, 1], 0.915, 356)
edge32 = edges.Edge([3, 2], 0.783, 380)
edge52 = edges.Edge([5, 2], 1.250, 306)
edge34 = edges.Edge([3, 4], 1.250, 610)
edge54 = edges.Edge([5, 4], 0.783, 380)
edge65 = edges.Edge([6, 5], 0.915, 356)
edge76 = edges.Edge([7, 6], 0.915, 356)
edge_list = [
edge52, edge21, edge10, edge07, edge76, edge65, edge32, edge34,
edge54
]
problem_23_6 = geometry.Geometry(8, boom_list, edge_list,
[217872, 167780], 24.2 * 10**9)
problem_23_6.cells = [[edge10, edge07, edge76, edge65, edge52, edge21],
[edge34, edge32, edge52, edge54]]
boom0.area = 1290
boom1.area = 645
boom2.area = 1290
boom3.area = 645
boom4.area = 645
boom5.area = 1290
boom6.area = 645
boom7.area = 1290
# calculate geometrical properties
problem_23_6.get_areas()
problem_23_6.construct_geometry()
problem_23_6.calc_centroid()
problem_23_6.moment_inertia_Iyy()
problem_23_6.moment_inertia_Izz()
for boom_element in boom_list:
boom_element.calc_y_dist(problem_23_6)
boom_element.calc_z_dist(problem_23_6)
# test moment of inertia
self.assertTrue(abs(problem_23_6.Izz * 10**(-6) - 181.2) < 1)
# calculate shear flow due to shear forces
problem_23_6_section = DiscreteSection.DiscreteSection(
neutral_axis, problem_23_6)
problem_23_6_section.calc_shear_flow_q_B(0, 66750, edge52)
problem_23_6_section.calc_closed_section_pure_shear_flow_q_0(edge52)
# test open section shear flow
self.assertTrue(abs(edge10.q_B - 0.0) < 1)
self.assertTrue(abs(edge07.q_B - (-72.6)) < 1)
self.assertTrue(abs(edge32.q_B - (-36.2)) < 1)
self.assertTrue(abs(edge21.q_B - 36.2) < 1)
self.assertTrue(abs(edge34.q_B) < 0.1)
self.assertTrue(abs(edge54.q_B - (-36.3)) < 1)
self.assertTrue(abs(edge52.q_B - 145.3) < 1)
self.assertTrue(abs(edge65.q_B - 36.3) < 1)
self.assertTrue(abs(edge76.q_B) < 1)
# test closed section shear flow
self.assertTrue(
abs(edge21.q_0 - (-39.2)) < 1 and abs(edge10.q_0 - (-39.2)) < 1
and abs(edge07.q_0 - (-39.2)) < 1 and abs(edge76.q_0 - (-39.2)) < 1
and abs(edge65.q_0 - (-39.2)) < 1)
self.assertTrue(
abs(edge32.q_0 - 17.8) < 1 and abs(edge34.q_0 - 17.8) < 1
and abs(edge54.q_0 - 17.8) < 1)
self.assertTrue(abs(edge52.q_0 - (-57)) < 1)
def test_shear_flow_pure_shear1(self):
# using problem 23.5 in Megson. Some sign conventions are switched for consistency.
# initialise booms
neutral_axis = (0, 1, 0)
boom0 = boom.Boom(0, [-635, -127], 0.0, neutral_axis)
boom1 = boom.Boom(1, [0, -203], 0.0, neutral_axis)
boom2 = boom.Boom(2, [763, -101], 0.0, neutral_axis)
boom3 = boom.Boom(3, [763, 101], 0.0, neutral_axis)
boom4 = boom.Boom(4, [0, 203], 0.0, neutral_axis)
boom5 = boom.Boom(5, [-635, 127], 0.0, neutral_axis)
boom_list = [boom0, boom1, boom2, boom3, boom4, boom5]
# initialise edges
edge45 = edges.Edge([4, 5], 0.915, 647)
edge14 = edges.Edge([1, 4], 2.032, 406)
edge10 = edges.Edge([1, 0], 0.915, 647)
edge05 = edges.Edge([0, 5], 1.625, 254)
edge43 = edges.Edge([4, 3], 0.559, 775)
edge32 = edges.Edge([3, 2], 1.220, 202)
edge21 = edges.Edge([2, 1], 0.559, 775)
edge_list = [edge45, edge14, edge10, edge05, edge43, edge32, edge21]
# initialise Geometry
problem_23_5 = geometry.Geometry(6, boom_list, edge_list,
[232000, 258000], 1.0)
problem_23_5.cells = [[edge43, edge32, edge21, edge14],
[edge45, edge14, edge10, edge05]]
# set boom areas to given values
boom0.area = 1290
boom1.area = 1936
boom2.area = 645
boom3.area = 645
boom4.area = 1936
boom5.area = 1290
problem_23_5.get_areas()
# calculate and verify geometrical properties
problem_23_5.construct_geometry()
problem_23_5.calc_centroid()
problem_23_5.moment_inertia_Iyy()
problem_23_5.moment_inertia_Izz()
self.assertTrue(abs(problem_23_5.Izy < 1))
self.assertTrue(abs(problem_23_5.Izz * 10**(-6) - 214.3) < 1)
for boom_element in boom_list:
boom_element.calc_y_dist(problem_23_5)
boom_element.calc_z_dist(problem_23_5)
# calculate shear flows
problem_23_5_section = DiscreteSection.DiscreteSection(
neutral_axis, problem_23_5)
problem_23_5_section.calc_shear_flow_q_B(0, 44500, edge14)
# test open section shear flows
self.assertTrue(abs(edge45.q_B) < 0.1 and abs(edge21.q_B) < 0.1)
self.assertTrue(abs(edge43.q_B) < 0.1 and abs(edge10.q_B) < 0.1)
self.assertTrue(abs(edge32.q_B - (-13.6)) < 1)
self.assertTrue(abs(edge14.q_B) - 81.7 < 1)
self.assertTrue(abs(edge05.q_B) - 34.07 < 1)
# calculate closed section shear flows
problem_23_5_section.calc_closed_section_pure_shear_flow_q_0(edge14)
# test open section shear flows
self.assertTrue(
abs(edge45.q_0 - 4.12) < 1 and abs(edge05.q_0 - 4.12) < 1
and abs(edge10.q_0 - 4.12) < 1)
self.assertTrue(
abs(edge43.q_0 - (-5.74)) < 1 and abs(edge21.q_0 - (-5.74)) < 1
and abs(edge32.q_0 - (-5.74)) < 1)
self.assertTrue(abs(edge14.q_0 - (-9.85)) < 1)
def initialise_problem():
stringer_area = 42 * 10**(-6)
neutral_axis = (0, 1, 0)
# CREATE LIST OF COORDINATES FOR BOOMS
# give the coordinates of the booms with respect to the hinge point
# for the first eight, they are on a straight line
coordinates = []
for n in range(16):
coordinates.append([((43.45 - 5.43125 / 2 * (n + 1)) * 10) * 10**(-3),
((1.40625 / 2 * (n + 1)) * 10) * 10**(-3)])
# booms 8, 9 and 10 are along a semi-circle
coordinates.append([
-112.5 * math.sin(math.pi / 8) * 10**(-3),
112.5 * math.cos(math.pi / 8) * 10**(-3)
])
coordinates.append([
-112.5 * math.sin(math.pi / 4) * 10**(-3),
112.5 * math.cos(math.pi / 4) * 10**(-3)
])
coordinates.append([
-112.5 * math.sin(3 * math.pi / 8) * 10**(-3),
112.5 * math.cos(3 * math.pi / 8) * 10**(-3)
])
coordinates.append([-112.5 * 10**(-3), 0.0])
# the last 8 are symmetric to the first eight wrt the z-axis
for i in range(18, -1, -1):
coords = coordinates[i]
coordinates.append([coords[0], -coords[1]])
# the ones on the spar are always at z=0 and distributed equally along the height of the spar
coordinates.append([0.0, (22.5 + 45) * 10**(-3)])
coordinates.append([0.0, 22.5 * 10**(-3)])
coordinates.append([0.0, -22.5 * 10**(-3)])
coordinates.append([0.0, (-22.5 - 45) * 10**(-3)])
# CREATE BOOM INSTANCES AND INSERT THEM IN GEOMETRY
booms = []
boom0 = boom.Boom(0, coordinates[0], 0.0, neutral_axis)
booms.append(boom0)
boom1 = boom.Boom(1, coordinates[1], stringer_area, neutral_axis)
booms.append(boom1)
boom2 = boom.Boom(2, coordinates[2], 0.0, neutral_axis)
booms.append(boom2)
boom3 = boom.Boom(3, coordinates[3], stringer_area, neutral_axis)
booms.append(boom3)
boom4 = boom.Boom(4, coordinates[4], 0.0, neutral_axis)
booms.append(boom4)
boom5 = boom.Boom(5, coordinates[5], stringer_area, neutral_axis)
booms.append(boom5)
boom6 = boom.Boom(6, coordinates[6], 0.0, neutral_axis)
booms.append(boom6)
boom7 = boom.Boom(7, coordinates[7], stringer_area, neutral_axis)
booms.append(boom7)
boom8 = boom.Boom(8, coordinates[8], 0.0, neutral_axis)
booms.append(boom8)
boom9 = boom.Boom(9, coordinates[9], stringer_area, neutral_axis)
booms.append(boom9)
boom10 = boom.Boom(10, coordinates[10], 0.0, neutral_axis)
booms.append(boom10)
boom11 = boom.Boom(11, coordinates[11], stringer_area, neutral_axis)
booms.append(boom11)
boom12 = boom.Boom(12, coordinates[12], 0.0, neutral_axis)
booms.append(boom12)
boom13 = boom.Boom(13, coordinates[13], stringer_area, neutral_axis)
booms.append(boom13)
boom14 = boom.Boom(14, coordinates[14], 0.0, neutral_axis)
booms.append(boom14)
boom15 = boom.Boom(15, coordinates[15], 0.0, neutral_axis)
booms.append(boom15)
# semi circle booms
boom16 = boom.Boom(16, coordinates[16], 0.0, neutral_axis)
booms.append(boom16)
boom17 = boom.Boom(17, coordinates[17], stringer_area, neutral_axis)
booms.append(boom17)
boom18 = boom.Boom(18, coordinates[18], 0.0, neutral_axis)
booms.append(boom18)
boom19 = boom.Boom(19, coordinates[19], stringer_area, neutral_axis)
booms.append(boom19)
boom20 = boom.Boom(20, coordinates[20], 0.0, neutral_axis)
booms.append(boom20)
boom21 = boom.Boom(21, coordinates[21], stringer_area, neutral_axis)
booms.append(boom21)
boom22 = boom.Boom(22, coordinates[22], 0.0, neutral_axis)
booms.append(boom22)
# lower straight line booms
boom23 = boom.Boom(23, coordinates[23], 0.0, neutral_axis)
booms.append(boom23)
boom24 = boom.Boom(24, coordinates[24], 0.0, neutral_axis)
booms.append(boom24)
boom25 = boom.Boom(25, coordinates[25], stringer_area, neutral_axis)
booms.append(boom25)
boom26 = boom.Boom(26, coordinates[26], 0.0, neutral_axis)
booms.append(boom26)
boom27 = boom.Boom(27, coordinates[27], stringer_area, neutral_axis)
booms.append(boom27)
boom28 = boom.Boom(28, coordinates[28], 0.0, neutral_axis)
booms.append(boom28)
boom29 = boom.Boom(29, coordinates[29], stringer_area, neutral_axis)
booms.append(boom29)
boom30 = boom.Boom(30, coordinates[30], 0.0, neutral_axis)
booms.append(boom30)
boom31 = boom.Boom(31, coordinates[31], stringer_area, neutral_axis)
booms.append(boom31)
boom32 = boom.Boom(32, coordinates[32], 0.0, neutral_axis)
booms.append(boom32)
boom33 = boom.Boom(33, coordinates[33], stringer_area, neutral_axis)
booms.append(boom33)
boom34 = boom.Boom(34, coordinates[34], 0.0, neutral_axis)
booms.append(boom34)
boom35 = boom.Boom(35, coordinates[35], stringer_area, neutral_axis)
booms.append(boom35)
boom36 = boom.Boom(36, coordinates[36], 0.0, neutral_axis)
booms.append(boom36)
boom37 = boom.Boom(37, coordinates[37], stringer_area, neutral_axis)
booms.append(boom37)
boom38 = boom.Boom(38, coordinates[38], 0.0, neutral_axis)
booms.append(boom38)
# booms on the spar
boom39 = boom.Boom(39, coordinates[39], 0.0, neutral_axis)
booms.append(boom39)
boom40 = boom.Boom(40, coordinates[40], 0.0, neutral_axis)
booms.append(boom40)
boom41 = boom.Boom(41, coordinates[41], 0.0, neutral_axis)
booms.append(boom41)
boom42 = boom.Boom(42, coordinates[42], 0.0, neutral_axis)
booms.append(boom42)
# CREATE EDGES INSTANCES AND PUT THEM IN A LIST
edge_list = []
edge10 = edges.Edge([1, 0], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge10)
edge21 = edges.Edge([2, 1], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge21)
edge32 = edges.Edge([3, 2], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge32)
edge43 = edges.Edge([4, 3], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge43)
edge54 = edges.Edge([5, 4], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge54)
edge65 = edges.Edge([6, 5], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge65)
edge76 = edges.Edge([7, 6], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge76)
edge87 = edges.Edge([8, 7], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge87)
edge98 = edges.Edge([9, 8], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge98)
edge109 = edges.Edge([10, 9], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge109)
edge1110 = edges.Edge([11, 10], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge1110)
edge1211 = edges.Edge([12, 11], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge1211)
edge1312 = edges.Edge([13, 12], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge1312)
edge1413 = edges.Edge([14, 13], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge1413)
edge1514 = edges.Edge([15, 14], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge1514)
# booms on semicircle
edge1615 = edges.Edge([16, 15], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge1615)
edge1716 = edges.Edge([17, 16], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge1716)
edge1817 = edges.Edge([18, 17], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge1817)
edge1918 = edges.Edge([19, 18], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge1918)
edge2019 = edges.Edge([20, 19], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge2019)
edge2120 = edges.Edge([21, 20], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge2120)
edge2221 = edges.Edge([22, 21], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge2221)
edge2322 = edges.Edge([23, 22], 1.1 * 10**(-3), 44.179 * 10**(-3))
edge_list.append(edge2322)
# booms on lower spar
edge2423 = edges.Edge([24, 23], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge2423)
edge2524 = edges.Edge([25, 24], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge2524)
edge2625 = edges.Edge([26, 25], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge2625)
edge2726 = edges.Edge([27, 26], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge2726)
edge2827 = edges.Edge([28, 27], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge2827)
edge2928 = edges.Edge([29, 28], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge2928)
edge3029 = edges.Edge([30, 29], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3029)
edge3130 = edges.Edge([31, 30], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3130)
edge3231 = edges.Edge([32, 31], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3231)
edge3332 = edges.Edge([33, 32], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3332)
edge3433 = edges.Edge([34, 33], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3433)
edge3534 = edges.Edge([35, 34], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3534)
edge3635 = edges.Edge([36, 35], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3635)
edge3736 = edges.Edge([37, 36], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3736)
edge3837 = edges.Edge([38, 37], 1.1 * 10**(-3), 56.103 * 0.5 * 10**(-3))
edge_list.append(edge3837)
edge038 = edges.Edge([0, 38], 1.1 * 10**(-3), 56.103 * 10**(-3))
edge_list.append(edge038)
# booms on the vertical spar
edge3915 = edges.Edge([39, 15], 2.9 * 10**(-3), 45 * 10**(-3))
edge_list.append(edge3915)
edge4039 = edges.Edge([40, 39], 2.9 * 10**(-3), 45 * 10**(-3))
edge_list.append(edge4039)
edge4140 = edges.Edge([41, 40], 2.9 * 10**(-3), 45 * 10**(-3))
edge_list.append(edge4140)
edge4241 = edges.Edge([42, 41], 2.9 * 10**(-3), 45 * 10**(-3))
edge_list.append(edge4241)
edge2342 = edges.Edge([23, 42], 2.9 * 10**(-3), 45 * 10**(-3))
edge_list.append(edge2342)
# CREATE INSTANCE OF AILERON GEOMETRY WITH ALL THE BOOMS
aileron_geometry = geometry.Geometry(
43, booms, edge_list, [19880.391 * 10**(-6), 36225 * 10**(-6)],
28 * 10**9)
aileron_geometry.construct_geometry()
aileron_geometry.cells = [[
edge038, edge3837, edge3736, edge3635, edge3534, edge3433, edge3332,
edge3231, edge3130, edge3029, edge2928, edge2827, edge2726, edge2625,
edge2524, edge2423, edge2342, edge4241, edge4140, edge4039, edge3915,
edge1514, edge1413, edge1312, edge1211, edge1110, edge109, edge98,
edge87, edge76, edge65, edge54, edge43, edge32, edge21, edge10
],
[
edge2019, edge1918, edge1817, edge1716,
edge1615, edge3915, edge4039, edge4140,
edge4241, edge2342, edge2322, edge2221,
edge2120
]]
# calculate areas of all booms
for element in booms:
element.calculate_area(aileron_geometry)
# insert them in aileron_geometry object
aileron_geometry.get_areas()
# calculate centroid position
aileron_geometry.calc_centroid()
for boom_element in booms:
boom_element.calc_y_dist(aileron_geometry)
boom_element.calc_z_dist(aileron_geometry)
# calculate moments of inertia
aileron_geometry.moment_inertia_Izz()
aileron_geometry.moment_inertia_Iyy()
# PLOT AND PRINT GEOMETRICAL PROPERTIES FOR VERIFICATION
aileron_geometry.plot_edges()
for it, el in enumerate(booms):
print('area of boom ', it, ' : ', aileron_geometry.boom_areas[it],
'[mm^2]')
print('centroid position : ', aileron_geometry.centroid)
print('z moment of inertia : ', aileron_geometry.Izz, ' [mm^4]')
print('y moment of inertia : ', aileron_geometry.Iyy, ' [mm^4]')
print('zy moment of inertia : ', aileron_geometry.Izy, '[mm^4]')
# GET THE LIST OF FORCES AND MOMENTS
file_name = "Loads.txt"
x_i_array = helpers.get_array_x_i(file_name)
Mx_array = helpers.get_array_Mx_i(file_name)
My_array = helpers.get_array_My_i(file_name)
Mz_array = helpers.get_array_Mz_i(file_name)
Sz_array = helpers.get_array_Sz_i(file_name)
Sy_array = helpers.get_array_Sy_i(file_name)
# create a matrix of stresses
stress_matrix = np.zeros((43, 101))
for j, location in enumerate(x_i_array):
for i, boom_member in enumerate(aileron_geometry.booms):
boom_member.calc_bending_stress(Mz_array[j], My_array[j],
aileron_geometry)
stress_matrix[i][j] = boom_member.bending_stress
# find maximum stress
max_stress_matrix = np.amax(stress_matrix, axis=1)
# set up matrix of shear stresses
stress_matrix_shear = np.zeros((len(aileron_geometry.edges), 101))
# set up lists
twist_rate_list = []
thetas_list = []
section_numbers = 100
step = 2.771 / section_numbers
thetas_list.append(0.453786)
file = open("thetas_list.txt", "w")
for i, x_i in enumerate(x_i_array):
# create new instance of section with new location
aileron_section = DiscreteSection.DiscreteSection(
neutral_axis, aileron_geometry)
# calculate shear flows due to pure shear and torque
aileron_section.calc_total_shear_flow(Sz_array[i], Sy_array[i],
Mx_array[i], edge2342)
# calculate shear stress due to total shear flows and insert in the shear stress matrix
aileron_section.calc_shear_stress()
for n1, edge_ex in enumerate(aileron_geometry.edges):
stress_matrix_shear[n1][i] = edge_ex.shear_stress
# append the twist rate (computed at the same time as torque shear flow) in the twist rate list
twist_rate_list.append(aileron_section.twist_rate)
# calculate theta with finite differences, append to the list and copy to the txt file
theta = twist_rate_list[i - 1] * step + thetas_list[i - 1]
thetas_list.append(theta)
file.write(str(float(theta)) + '\n')
# find the maximum shear stress on each rib
print('the maximum shear stress in rib A : ',
np.max(stress_matrix_shear[:, 97]))
print('the maximum shear stress in rib B : ',
np.max(stress_matrix_shear[:, 51]))
print('the maximum shear stress in rib C : ',
np.max(stress_matrix_shear[:, 41]))
print('the maximum shear stress in rib D : ',
np.max(stress_matrix_shear[:, 18]))
# find the maximum normal stress on each rib
print('the maximum normal stress in rib A : ', np.max(stress_matrix[:,
97]))
print('the maximum normal stress in rib A : ', np.max(stress_matrix[:,
51]))
print('the maximum normal stress in rib A : ', np.max(stress_matrix[:,
41]))
print('the maximum normal stress in rib A : ', np.max(stress_matrix[:,
18]))