.. index:: fix multisphere/break fix multisphere/break command ============================= Syntax """""" .. parsed-literal:: fix ID group-ID multisphere/break keyword value ... * ID, group-ID are documented in :doc:`fix ` command * multisphere/break = style name of this fix command * keywords = same as for :doc:`fix multisphere `, in addition: *trigger_threshold* and *trigger_timeStep* and *trigger_name* (or the deprecated:*trigger_fixName*) .. parsed-literal:: *trigger_threshold* value = *x in units matching that of trigger_fixName* this allows the user the specify a threshold value that will be compared with the per-atom value provided by trigger_fixName, e.g., the residence time in a region (e.g., computed via a fix property/atom/tracer/residencetime). if the threshold is exceeded, the multisphere particle will break. *trigger_timeStep* value = *x in steps* this allows the user to activate the fix after a predefined number of steps. *trigger_name* the user must specify a reference to a fix property/atom or variable of style atom that is used as the trigger value. .. parsed-literal:: *trigger_fixName* (deprecated!) the user must specify the name of the fix that specified per-atom information that is used as the trigger value. Examples """""""" .. parsed-literal:: fix integr grpMulti1 multisphere/break allow_group_and_set yes trigger_threshold 0.1 trigger_timeStep 0 trigger_name f_resTimeMill fix integr grpMulti2 multisphere/break allow_group_and_set yes trigger_threshold 1 trigger_timeStep 0 trigger_name f_pressure**1** fix integr grpMulti3 multisphere/break allow_group_and_set yes trigger_threshold 50 trigger_timeStep 10 trigger_name v_myAtomVariable Description """"""""""" The integration that is performed by this command is euqivalent to :doc:`fix_multisphere `. However, the user can trigger breakage events, which will destroy the "body" the atoms are in. The trigger is imiplemented such that in case the trigger value of one atom in a body exceeds the threshold value, the whole body will break. There are no fragments: all atoms that constitutea body will be released upon breakage. .. note:: the atoms in a body MUST NOT overlap, since the atoms are simply released from the body without adjusting their size or their position. .. note:: A integrator for the spheres needs to be available (e.g. :doc:`fix nve/sphere `) otherwise the multisphere will fragment but no futher integration of the particles will occur ---------- Restart, fix_modify, output, run start/stop, minimize info """""""""""""""""""""""""""""""""""""""""""""""""""""""""" Same as for :doc:`fix_multisphere `. Restrictions """""""""""" Same as for :doc:`fix_multisphere `. Related commands """""""""""""""" :doc:`fix_multisphere ` **Default:** none .. _liws: http://www.cfdem.com .. _ld: Manual.html .. _lc: Section_commands.html#comm