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fix particledistribution/discrete command

Syntax:

fix ID group-ID particledistribution/discrete seed ntemp t_id t_m ... 

• ID, group-ID are documented in fix command

• particledistribution/discrete = style name of this fix command

• seed = random number generator seed (integer value)

• ntemp = number of particle templates to be used in this command

• zero or more t_id/t_m pairs are appended, number of pairs must match ntemp

  t_id = id of a fix of type particletemplate/sphere
  t_m = mass % for this template in the distribution
  
   

Examples:

fix pdd1 all particledistribution/discrete 6778  1 pts1 1.0
fix pdd1 all particledistribution/discrete 1239  2 pts1 0.3 pts2 0.7 

LIGGGHTS vs. LAMMPS Info:

This LIGGGHTS command is not available in LAMMPS.

Description:

Define a discrete particle distribution that defines a discrete particle distribution to be inserted by the fix_pour_dev command. It takes several templates of type fix_particletemplate_sphere as inputs, which define the properties of the single particles that are part of the distribution.

At insertion, particles are chosen according to the mass-% distribution as defined by each pair (t_id, t_m). Note that the sum of all weights t_m must be equal to 1.0 – if this is not the case the user is warned at the distribution is normalized. Note that large particles are inserted first, so that a higher volume fraction can be achieved. If not all desired insertions could be performed, it is likely that the distribution is not accurately reproduced.

IMPORTANT NOTE: As opposed to the number-based distributions used by fix_pour and fix_pour_legacy, this fix uses the more common distribution based on mass-% as input (as does fix_particletemplate_sphere).

Restart, fix_modify, output, run start/stop, minimize info:

Information about the random state in this fix is written to binary restart files so you can restart a simulation with the same particles being chosen for insertion. None of the fix_modify options are relevant to this fix. No global scalar or vector or per-atom quantities are stored by this fix for access by various output commands. No parameter of this fix can be used with the start/stop keywords of the run command. This fix is not invoked during energy minimization.

Restrictions: none

Related commands:

fix_particledistribution_discrete fix_pour_dev

Default: none