Extract multi-stage cyclic results

In this script, a multi-stage modal analysis with cyclic symmetry is processed to show how to expand the mesh and results.

Perform required imports

This example uses a supplied file that you can get by importing the DPF examples package.

from ansys.dpf import post
from ansys.dpf.post import examples

Get Simulation object

Get the Simulation object that allows access to the result. The Simulation object must be instantiated with the path for the result file. For example, "C:/Users/user/my_result.rst" on Windows or "/home/user/my_result.rst" on Linux.

example_path = examples.download_multi_stage_cyclic_result()
simulation = post.ModalMechanicalSimulation(example_path)

# print the simulation to get an overview of what's available
print(simulation)

Modal Mechanical Simulation.


Data Sources
------------------------------
/opt/hostedtoolcache/Python/3.8.16/x64/lib/python3.8/site-packages/ansys/dpf/core/examples/multistage/multistage.rst

DPF Model
------------------------------
Modal analysis
Unit system: MKS: m, kg, N, s, V, A, degC
Physics Type: Mechanical
Available results:
     -  displacement: Nodal Displacement
     -  stress: ElementalNodal Stress
     -  elastic_strain: ElementalNodal Strain
     -  structural_temperature: ElementalNodal Temperature
------------------------------
DPF  Meshed Region:
  3595 nodes
  1557 elements
  Unit: m
  With solid (3D) elements
------------------------------
DPF  Time/Freq Support:
  Number of sets: 6
Cumulative     Frequency (Hz) LoadStep       Substep        Harmonic index
1              188.385357     1              1              0.000000
2              325.126418     1              2              0.000000
3              595.320548     1              3              0.000000
4              638.189511     1              4              0.000000
5              775.669703     1              5              0.000000
6              928.278013     1              6              0.000000

Extract expanded displacement norm

displacement_norm = simulation.displacement(
    norm=True,
    expand_cyclic=True,
)
print(displacement_norm)
displacement_norm.plot()

 results     U_N (m)
 set_ids           1
node_ids
    1376  5.2953e-02
    4971  5.2953e-02
    7191  5.2953e-02
    9411  5.2953e-02
   11631  5.2953e-02
   13851  5.2953e-02
     ...

Extract equivalent von Mises nodal stress without expansion

stress_vm_sector_1_both_stages = simulation.stress_eqv_von_mises_nodal(
    expand_cyclic=False,
)
print(stress_vm_sector_1_both_stages)
stress_vm_sector_1_both_stages.plot()

    results   S_VM (Pa)
    set_ids           1
base_sector           1
      stage           0           1
   node_ids
       1460  6.8763e+09  1.3425e+10
       1622  7.0456e+09  1.5608e+10
       1644  8.0643e+09  1.2895e+10
       1660  8.5795e+09  1.6837e+10
       1490  6.5577e+09  1.1323e+10
       1596  6.4393e+09  1.0031e+10
        ...

Extract equivalent von Mises nodal stress expanded on the first four sectors of the first stage

stress_vm_sectors_1_2_3_4_first_stage = simulation.stress_eqv_von_mises_nodal(
    expand_cyclic=[1, 2, 3, 4],
)
print(stress_vm_sectors_1_2_3_4_first_stage)
stress_vm_sectors_1_2_3_4_first_stage.plot()

 results   S_VM (Pa)
 set_ids           1
node_ids
    5071  6.2894e+09
    5218  6.9084e+09
    1644  8.0643e+09
    1660  8.5795e+09
    7291  6.2894e+09
    7438  6.9084e+09
     ...

Extract equivalent von Mises nodal stress expanded on the first two sectors of both stages

stress_vm_sectors_1_2_both_stages = simulation.stress_eqv_von_mises_nodal(
    expand_cyclic=[[1, 2], [1, 2]],
)
print(stress_vm_sectors_1_2_both_stages)
stress_vm_sectors_1_2_both_stages.plot()

 results   S_VM (Pa)
 set_ids           1
node_ids
    5071  6.2894e+09
    5218  6.9084e+09
    1644  8.0643e+09
    1660  8.5795e+09
    7291  6.8763e+09
    7438  7.0456e+09
     ...