MAPDL 3D Beam Example

This is a simple example that loads an archive file containing a beam and then runs a modal analysis using the simplified modal_analysis method.

First, start by launching MAPDL as a service.

from ansys.mapdl.reader import examples

from ansys.mapdl.core import launch_mapdl

mapdl = launch_mapdl()

# load a beam stored as an example archive file and mesh it
mapdl.cdread("db", examples.hexarchivefile)
mapdl.esel("s", "ELEM", vmin=5, vmax=20)
mapdl.cm("ELEM_COMP", "ELEM")
mapdl.nsel("s", "NODE", vmin=5, vmax=20)
mapdl.cm("NODE_COMP", "NODE")

# boundary conditions
mapdl.allsel()

# dummy steel properties
mapdl.prep7()
mapdl.mp("EX", 1, 200e9)  # Elastic moduli in Pa (kg/(m*s**2))
mapdl.mp("DENS", 1, 7800)  # Density in kg/m3
mapdl.mp("NUXY", 1, 0.3)  # Poissons Ratio
mapdl.emodif("ALL", "MAT", 1)

# fix one end of the beam
mapdl.nsel("S", "LOC", "Z")
mapdl.d("all", "all")
mapdl.allsel()

# plot the boundary conditions
mapdl.nplot(plot_bc=True)

mapdl.mxpand(elcalc="YES")
mapdl.modal_analysis(nmode=6)

View the results using the pyansys result object

result = mapdl.result
print(result)

Access nodal displacement values

nnum, disp = result.nodal_displacement(0)

# print the nodes 50 - 59
for i in range(49, 59):
    print(nnum[i], disp[i])

Plot a modal result

result.plot_nodal_displacement(0, show_edges=True)

Animate a modal result result.animate_nodal_solution(0, show_edges=True, loop=False, displacement_factor=10, movie_filename='demo.gif')

Stop mapdl

mapdl.exit()