superquadric command

Warning

GPU support for this command has not been tested and may not work as expected.

Syntax

fix ID group-ID change/size/superquadric keywords values

ID, is documented in fix command.
change/size/superquadric = style name of this fix command
zero or more keyword/value pairs may be appended
keyword = force or region or accel_max

mass_change_rate value = mcr
  mcr = mass change rate (mass/time units)
region value = region-ID
  region-ID = ID of region atoms must be in to have added mass

Examples

fix grow all change/size/superquadric mass_change_rate 0.1 region grow_reg

Description

This fix adds mass and grows superquadric particles isotropically in the fix group, to mimic the effect of mass transfer, such as spray coating. In a first step, the eligible particles are tallied (see also region keyword*. Then, the mass and size change is distributed among eligible particles in a way so that each particle gets added mass proportional to its volume. The mass_change_rate keyword is used to define the added mass per time. Density is assumed to be constant during this process.

If the region keyword is used, the atom must also be in the specified geometric region in order to be eligible to have mass added and growth applied.

Restart, fix_modify, output, run start/stop

This fix does not need to write data to binary restart files. None of the fix_modify options are relevant to this fix. No output is 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.

Restrictions

This fix does not work with fix multisphere This fix requires atom_style superquadric.

Default

mass_change_rate = 0. region = whole simulation box