Note
Go to the end to download the full example code.
MAPDL modal beam analysis example#
This example demonstrates how to perform a simple modal analysis and animate its results.
Objective#
This example models a simple 3D elastic beam made of BEAM188 elements. These beams elements are made of a linear elastic material similar to steel, and have a rectangular section.
Procedure#
Launch MAPDL instance
Material properties
Geometry
Finite element model
Boundary conditions
Solving the model
Post-processing
Stop MAPDL
Launch MAPDL instance#
Launch MAPDL with interactive plotting
from ansys.mapdl.core import launch_mapdl
nmodes = 10
# start MAPDL
mapdl = launch_mapdl()
print(mapdl)
Product: Ansys Mechanical Enterprise Academic Student
MAPDL Version: 24.2
ansys.mapdl Version: 0.69.dev0
Define material#
Define material
mapdl.prep7()
mapdl.mp("EX", 1, 2.1e11)
mapdl.mp("PRXY", 1, 0.3)
mapdl.mp("DENS", 1, 7800)
MATERIAL 1 DENS = 7800.000
Create geometry#
Create keypoints and line
mapdl.k(1)
mapdl.k(2, 10)
mapdl.l(1, 2)
mapdl.lplot()
Define finite element model#
Define element type/section type - Rectangular beam section.
mapdl.et(1, "BEAM188")
mapdl.sectype(1, "BEAM", "RECT")
mapdl.secoffset("CENT")
mapdl.secdata(2, 1)
# Mesh the line
mapdl.type(1)
mapdl.esize(1)
mapdl.lesize("ALL")
mapdl.lmesh("ALL")
mapdl.eplot()
mapdl.finish()
***** ROUTINE COMPLETED ***** CP = 0.000
Specify boundary conditions#
Fully fixed (clamped) end.
mapdl.solution() # Entering the solution processor.
mapdl.nsel("S", "LOC", "X", "0")
mapdl.d("ALL", "ALL")
mapdl.allsel()
mapdl.nplot(plot_bc=True, nnum=True)
Solve the model#
Setting modal analysis
mapdl.antype("MODAL")
mapdl.modopt("LANB", nmodes, 0, 200)
mapdl.solve()
mapdl.finish()
FINISH SOLUTION PROCESSING
***** ROUTINE COMPLETED ***** CP = 0.000
Postprocess#
Enter the post processor (post1)
mapdl.post1()
output = mapdl.set("LIST")
print(output)
result = mapdl.result
***** INDEX OF DATA SETS ON RESULTS FILE *****
SET TIME/FREQ LOAD STEP SUBSTEP CUMULATIVE
1 8.3233851 1 1 1
2 16.274527 1 2 2
3 50.891463 1 3 3
4 60.248510 1 4 4
5 89.208488 1 5 5
6 129.85203 1 6 6
7 138.63765 1 7 7
8 182.23482 1 8 8
Animate results
mode2plot = 2
normalizeDisplacement = 1 / result.nodal_displacement(mode2plot - 1)[1].max()
result.plot_nodal_displacement(
mode2plot,
show_displacement=True,
displacement_factor=normalizeDisplacement,
n_colors=10,
)
result.animate_nodal_displacement(
mode2plot,
loop=False,
add_text=False,
n_frames=100,
displacement_factor=normalizeDisplacement,
show_axes=False,
background="w",
movie_filename="animation.gif",
off_screen=True,
)
Rendering animation: 0%| | 0/100 [00:00<?, ?it/s]
Rendering animation: 1%| | 1/100 [00:00<00:16, 6.14it/s]
Rendering animation: 4%|▍ | 4/100 [00:00<00:06, 14.30it/s]
Rendering animation: 7%|▋ | 7/100 [00:00<00:05, 17.51it/s]
Rendering animation: 10%|█ | 10/100 [00:00<00:04, 19.27it/s]
Rendering animation: 13%|█▎ | 13/100 [00:00<00:04, 20.33it/s]
Rendering animation: 16%|█▌ | 16/100 [00:00<00:04, 20.68it/s]
Rendering animation: 19%|█▉ | 19/100 [00:01<00:03, 20.56it/s]
Rendering animation: 22%|██▏ | 22/100 [00:01<00:03, 20.85it/s]
Rendering animation: 25%|██▌ | 25/100 [00:01<00:03, 21.26it/s]
Rendering animation: 28%|██▊ | 28/100 [00:01<00:03, 21.45it/s]
Rendering animation: 31%|███ | 31/100 [00:01<00:03, 20.73it/s]
Rendering animation: 34%|███▍ | 34/100 [00:01<00:03, 21.07it/s]
Rendering animation: 37%|███▋ | 37/100 [00:01<00:02, 21.31it/s]
Rendering animation: 40%|████ | 40/100 [00:01<00:02, 21.13it/s]
Rendering animation: 43%|████▎ | 43/100 [00:02<00:02, 20.77it/s]
Rendering animation: 46%|████▌ | 46/100 [00:02<00:02, 21.15it/s]
Rendering animation: 49%|████▉ | 49/100 [00:02<00:02, 21.37it/s]
Rendering animation: 52%|█████▏ | 52/100 [00:02<00:02, 21.36it/s]
Rendering animation: 55%|█████▌ | 55/100 [00:02<00:02, 21.05it/s]
Rendering animation: 58%|█████▊ | 58/100 [00:02<00:01, 21.25it/s]
Rendering animation: 61%|██████ | 61/100 [00:02<00:01, 21.47it/s]
Rendering animation: 64%|██████▍ | 64/100 [00:03<00:01, 21.58it/s]
Rendering animation: 67%|██████▋ | 67/100 [00:03<00:01, 21.11it/s]
Rendering animation: 70%|███████ | 70/100 [00:03<00:01, 21.32it/s]
Rendering animation: 73%|███████▎ | 73/100 [00:03<00:01, 21.09it/s]
Rendering animation: 76%|███████▌ | 76/100 [00:03<00:01, 21.30it/s]
Rendering animation: 79%|███████▉ | 79/100 [00:03<00:01, 20.93it/s]
Rendering animation: 82%|████████▏ | 82/100 [00:03<00:00, 21.23it/s]
Rendering animation: 85%|████████▌ | 85/100 [00:04<00:00, 21.47it/s]
Rendering animation: 88%|████████▊ | 88/100 [00:04<00:00, 21.55it/s]
Rendering animation: 91%|█████████ | 91/100 [00:04<00:00, 21.05it/s]
Rendering animation: 94%|█████████▍| 94/100 [00:04<00:00, 21.26it/s]
Rendering animation: 97%|█████████▋| 97/100 [00:04<00:00, 21.36it/s]
Rendering animation: 100%|██████████| 100/100 [00:04<00:00, 21.50it/s]
Rendering animation: 100%|██████████| 100/100 [00:12<00:00, 8.30it/s]
[(16.153550716504107, 11.153550716504107, 11.153550716504107),
(5.0, 0.0, 0.0),
(0.0, 0.0, 1.0)]
Stop MAPDL#
mapdl.finish()
mapdl.exit()
Total running time of the script: (0 minutes 13.851 seconds)