Syntax: +
+compute ID group-ID dilatation/atom ++
Examples: +
+compute 1 all dilatation/atom ++
Description: +
+Define a computation that calculates the per-atom dilatation for each +atom in a group. This is a quantity relevant for Peridynamics +models. +
+For small deformation, dilatation of is the measure of the volumetric +strain. +
+The dilatation "theta" for each peridynamic particle I is calculated +as a sum over its neighbors with unbroken bonds, where the +contribution of the IJ pair is a function of the change in bond length +(versus the initial length in the reference state), the volume +fraction of the particles and an influence function. See the +PDLAMMPS user +guide for a formal +definition of dilatation. +
+This command can only be used with a subset of the Peridynamic pair +styles: peri/lps, peri/ves and peri/eps. +
+The dilatation value will be 0.0 for atoms not in the specified +compute group. +
+Output info: +
+This compute calculates a per-atom vector, which can be accessed by +any command that uses per-atom values from a compute as input. See +Section_howto 15 for an overview of LAMMPS output options. +
+The per-atom vector values are unitlesss numbers (theta) >= 0.0. +
+Restrictions: +
+This compute is part of the PERI package. It is only enabled if +LAMMPS was built with that package. See the Making +LAMMPS section for more info. +
+Related commands: +
+compute damage, compute +plasticity +
+Default: none +
+ diff --git a/doc/compute_dilatation_atom.txt b/doc/compute_dilatation_atom.txt new file mode 100644 index 0000000000..f3b3328b54 --- /dev/null +++ b/doc/compute_dilatation_atom.txt @@ -0,0 +1,65 @@ +"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 dilatation/atom command :h3 + +[Syntax:] + +compute ID group-ID dilatation/atom :pre + +ID, group-ID are documented in compute command +dilation/atom = style name of this compute command :ul + +[Examples:] + +compute 1 all dilatation/atom :pre + +[Description:] + +Define a computation that calculates the per-atom dilatation for each +atom in a group. This is a quantity relevant for "Peridynamics +models"_pair_peri.html. + +For small deformation, dilatation of is the measure of the volumetric +strain. + +The dilatation "theta" for each peridynamic particle I is calculated +as a sum over its neighbors with unbroken bonds, where the +contribution of the IJ pair is a function of the change in bond length +(versus the initial length in the reference state), the volume +fraction of the particles and an influence function. See the +"PDLAMMPS user +guide"_http://www.sandia.gov/~mlparks/papers/PDLAMMPS.pdf for a formal +definition of dilatation. + +This command can only be used with a subset of the Peridynamic "pair +styles"_pair_peri.html: peri/lps, peri/ves and peri/eps. + +The dilatation value will be 0.0 for atoms not in the specified +compute group. + +[Output info:] + +This compute calculates a per-atom vector, which can be accessed by +any command that uses per-atom values from a compute as input. See +Section_howto 15 for an overview of LAMMPS output options. + +The per-atom vector values are unitlesss numbers (theta) >= 0.0. + +[Restrictions:] + +This compute is part of the PERI package. It is only enabled if +LAMMPS was built with that package. See the "Making +LAMMPS"_Section_start.html#start_3 section for more info. + +[Related commands:] + +"compute damage"_compute_damage.html, "compute +plasticity"_compute_plasticity.html + +[Default:] none diff --git a/doc/compute_plasticity_atom.html b/doc/compute_plasticity_atom.html new file mode 100644 index 0000000000..0c3dfeb16a --- /dev/null +++ b/doc/compute_plasticity_atom.html @@ -0,0 +1,72 @@ + +Syntax: +
+compute ID group-ID plasticity/atom ++
Examples: +
+compute 1 all plasticity/atom ++
Description: +
+Define a computation that calculates the per-atom plasticity for each +atom in a group. This is a quantity relevant for Peridynamics +models. +
+The plasticity for a Peridynamic particle is the so-called consistency +parameter (lambda). For elastic deformation lambda = 0, otherwise +lambda > 0 for plastic deformation. For details, see +(Mitchell) and the PDF doc included in the LAMMPS +distro in doc/PDF/PDLammps_EPS.pdf. +
+This command can be invoked for one of the Peridynamic pair +styles: peri/eps. +
+The plasticity value will be 0.0 for atoms not in the specified +compute group. +
+Output info: +
+This compute calculates a per-atom vector, which can be accessed by +any command that uses per-atom values from a compute as input. See +Section_howto 15 for an overview of LAMMPS output options. +
+The per-atom vector values are unitlesss numbers (lambda) >= 0.0. +
+Restrictions: +
+This compute is part of the PERI package. It is only enabled if +LAMMPS was built with that package. See the Making +LAMMPS section for more info. +
+Related commands: +
+compute damage, compute +dilatation +
+Default: none +
+(Mitchell) Mitchell, "A non-local, ordinary-state-based +viscoelasticity model for peridynamics", Sandia National Lab Report, +8064:1-28 (2011). +
+ diff --git a/doc/compute_plasticity_atom.txt b/doc/compute_plasticity_atom.txt new file mode 100644 index 0000000000..29882213a5 --- /dev/null +++ b/doc/compute_plasticity_atom.txt @@ -0,0 +1,66 @@ +"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 plasticity/atom command :h3 + +[Syntax:] + +compute ID group-ID plasticity/atom :pre + +ID, group-ID are documented in compute command +plasticity/atom = style name of this compute command :ul + +[Examples:] + +compute 1 all plasticity/atom :pre + +[Description:] + +Define a computation that calculates the per-atom plasticity for each +atom in a group. This is a quantity relevant for "Peridynamics +models"_pair_peri.html. + +The plasticity for a Peridynamic particle is the so-called consistency +parameter (lambda). For elastic deformation lambda = 0, otherwise +lambda > 0 for plastic deformation. For details, see +"(Mitchell)"_#Mitchell and the PDF doc included in the LAMMPS +distro in "doc/PDF/PDLammps_EPS.pdf"_PDF/PDLammps_EPS.pdf. + +This command can be invoked for one of the Peridynamic "pair +styles"_pair_peri.html: peri/eps. + +The plasticity value will be 0.0 for atoms not in the specified +compute group. + +[Output info:] + +This compute calculates a per-atom vector, which can be accessed by +any command that uses per-atom values from a compute as input. See +Section_howto 15 for an overview of LAMMPS output options. + +The per-atom vector values are unitlesss numbers (lambda) >= 0.0. + +[Restrictions:] + +This compute is part of the PERI package. It is only enabled if +LAMMPS was built with that package. See the "Making +LAMMPS"_Section_start.html#start_3 section for more info. + +[Related commands:] + +"compute damage"_compute_damage.html, "compute +dilatation"_compute_dilatation.html + +[Default:] none + +:line + +:link(Mitchell) +[(Mitchell)] Mitchell, "A non-local, ordinary-state-based +viscoelasticity model for peridynamics", Sandia National Lab Report, +8064:1-28 (2011).