fix property/add command

Syntax

fix ID group-ID property/add keywords values

• ID, group-ID is documented in fix command.

• property/add = style name of this fix command

• zero or more keyword/value pairs may be appended

• keyword = property or value or scale or region or compute_surface

property value = p-ID
  p-ID = valid ID of the fix property/atom that should be added to
value values = val
  val = value to assign to the temperature or heat source of the particles (constant or equal-style variable)
scale values = const or surface or volume
  const = do not scale value
  surface = scale value with particle surface
  volume = scale value with particle volume
  divmass = divide value by particle mass
  divvol = divide value by particle volume
region value = region-ID
  region-ID = ID of region particles must be in
compute_surface = compute-surface-ID
  compute-surface-ID = ID of a compute surface command
use_as_rate value = 'yes' or 'no'
  yes = Use the value as a rate; divide it among affected particles
  no = Add value to each affected particle

Examples

fix addheat all property/add property temp value 320.

Description

This fix allows to add to the value for a fix property/atom , such as temperature or heat source in conjunction with a fix that solves for heat transfer, such as fix heat/gran/conduction .

Keyword property expects a valid ID of the fix property/atom that should be added to, and the value defined by the value keyword is added each time-step. value can either be a constant expression or refer to an equal-style variable

Keyword scale can be used to define if value should be added to the property directly, or scaled by the surface area of particle (value * radius * radius * pi), or scaled by the volume of the particle (value * radius * radius * radius * 4*pi/3). In addition it is possible to divide the value by the particle mass (divmass) or particle volume (divvol).

Keywords region and compute_surface can be used to further refine the selection of particles that the operation is applied to. If the region keyword is used, the atom must be in the specified geometric region. If the compute_surface keyword is used, the atom must be on the surface of the particle bed, as defined by a compute surface command.

Restart, fix_modify, output, run start/stop

This fix writes no data to binary restart files . 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.

Restrictions

None

Related commands

fix heat/gran/conduction

Default

scale = const, use_as_rate = no