lammps/doc/compute_erotate_asphere.txt

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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)
:line
compute erotate/asphere command :h3
[Syntax:]
compute ID group-ID erotate/asphere :pre
ID, group-ID are documented in "compute"_compute.html command
erotate/asphere = style name of this compute command :ul
[Examples:]
compute 1 all erotate/asphere :pre
[Description:]
Define a computation that calculates the rotational kinetic energy of
a group of aspherical particles. The aspherical particles can be
ellipsoids, or line segments, or triangles. See the
"atom_style"_atom_style.html and "read_data"_read_data.html commands
for descriptions of these options.
For all 3 types of particles, the rotational kinetic energy is
computed as 1/2 I w^2, where I is the inertia tensor for the
aspherical particle and w is its angular velocity, which is computed
from its angular momentum if needed.
IMPORTANT NOTE: For "2d models"_dimension.html, ellipsoidal particles
are treated as ellipsoids, not ellipses, meaning their moments of
inertia will be the same as in 3d.
[Output info:]
This compute calculates a global scalar (the KE). This value can be
used by any command that uses a global scalar value from a compute as
input. See "Section_howto 15"_Section_howto.html#howto_15 for an
overview of LAMMPS output options.
The scalar value calculated by this compute is "extensive". The
scalar value will be in energy "units"_units.html.
[Restrictions:]
This compute requires that ellipsoidal particles atoms store a shape
and quaternion orientation and angular momentum as defined by the
"atom_style ellipsoid"_atom_style.html command.
This compute requires that line segment particles atoms store a length
and orientation and angular velocity as defined by the "atom_style
line"_atom_style.html command.
This compute requires that triangular particles atoms store a size and
shape and quaternion orientation and angular momentum as defined by
the "atom_style tri"_atom_style.html command.
All particles in the group must be finite-size. They cannot be point
particles.
[Related commands:] none
"compute erotate/sphere"_compute_erotate_sphere.html
[Default:] none