Project cell values to mesh-points

This section demonstrates how to move cell-values, located at the quadrature points of cells, to mesh-points. The results of project(), topoints() and extrapolate() are compared for the Cauchy stresses of a rectangular block under compression.

import felupe as fem

region = fem.RegionQuad(mesh=fem.Rectangle(b=(2, 1), n=(11, 6)))
field = fem.FieldContainer([fem.FieldPlaneStrain(region, dim=2)])

boundaries = fem.dof.uniaxial(
    field, clamped=True, move=-0.3, axis=1, return_loadcase=False
)
solid = fem.SolidBody(umat=fem.NeoHooke(mu=1, bulk=5), field=field)

job = fem.Job(steps=[fem.Step(items=[solid], boundaries=boundaries)]).evaluate()

Cell-based results, like Cauchy stresses, are not projected to mesh-points by default. Different methods may be used to move the cell-data to the mesh-points.

import pyvista as pv

plotter = pv.Plotter(shape=(2, 2))
kwargs = dict(name="Cauchy Stress", component=1, plotter=plotter)

plotter.subplot(0, 0)
kwargs_sbar = dict(interactive=False, title="Cauchy Stress YY (None)")
solid.plot(project=None, **kwargs, scalar_bar_args=kwargs_sbar)

plotter.subplot(0, 1)
kwargs_sbar = dict(interactive=False, title="Cauchy Stress YY (topoints)")
solid.plot(project=fem.topoints, **kwargs, scalar_bar_args=kwargs_sbar)

plotter.subplot(1, 0)
kwargs_sbar = dict(interactive=False, title="Cauchy Stress YY (project)")
solid.plot(project=fem.project, **kwargs, scalar_bar_args=kwargs_sbar)

plotter.subplot(1, 1)
kwargs_sbar = dict(interactive=False, title="Cauchy Stress YY (extrapolate)")
solid.plot(project=fem.tools.extrapolate, **kwargs, scalar_bar_args=kwargs_sbar)

plotter.show()