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 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.
IMPORTANT NOTE: For "2d models"_dimension.html, 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 "this section"_Section_howto.html#4_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 particles be represented as extended
ellipsoids and not point particles. This means they will have an
angular momentum and a shape which is determined by the
"shape"_shape.html command.
This compute requires that atoms store angular momentum and a
quaternion to represent their orientation, as defined by the
"atom_style"_atom_style.html. It also require they store a per-type
"shape"_shape.html. The particles cannot store a per-particle
diameter or per-particle mass.
All particles in the group must be finite-size. They cannot be point
particles, but they can be aspherical or spherical.
[Related commands:] none
"compute erotate/sphere"_compute_erotate_sphere.html
[Default:] none