fix ID group-ID heat N eflux-
region value = region-ID + region-ID = ID of region atoms must be in to have added force ++
Examples:
fix 3 qin heat 1 1.0 -fix 4 qout heat 1 -1.0 +fix 4 qout heat 1 -1.0 region top
Description:
Add non-translational kinetic energy (heat) to a group of atoms such that their aggregate momentum is conserved. Two of these fixes can be used to establish a temperature gradient across a simulation domain by -adding heat to one group of atoms (hot reservoir) and subtracting heat -from another (cold reservoir). E.g. a simulation sampling from the -McDLT ensemble. Note that the fix is applied to a group of atoms, not -a geometric region, so that the same set of atoms is affected wherever -they may move to. +adding heat (energy) to one group of atoms (hot reservoir) and +subtracting heat from another (cold reservoir). E.g. a simulation +sampling from the McDLT ensemble. +
+If the region keyword is used, the atom must be in both the group +and the specified geometric region in order to have +energy added or subtracted to it. If not specified, then the atoms in +the group are affected wherever they may move to.
Heat addition/subtraction is performed every N timesteps. The eflux parameter determines the change in aggregate energy of the entire diff --git a/doc/fix_heat.txt b/doc/fix_heat.txt index 2f9e937892..2a494d5e66 100644 --- a/doc/fix_heat.txt +++ b/doc/fix_heat.txt @@ -12,26 +12,34 @@ fix heat command :h3 fix ID group-ID heat N eflux :pre -ID, group-ID are documented in "fix"_fix.html command -heat = style name of this fix command -N = add/subtract heat every this many timesteps -eflux = rate of heat addition or subtraction (energy/time units) :ul +ID, group-ID are documented in "fix"_fix.html command :ulb,l +heat = style name of this fix command :l +N = add/subtract heat every this many timesteps :l +eflux = rate of heat addition or subtraction (energy/time units) :l +zero or more keyword/value pairs may be appended to args :l +keyword = {region} :l + {region} value = region-ID + region-ID = ID of region atoms must be in to have added force :pre +:ule [Examples:] fix 3 qin heat 1 1.0 -fix 4 qout heat 1 -1.0 :pre +fix 4 qout heat 1 -1.0 region top :pre [Description:] Add non-translational kinetic energy (heat) to a group of atoms such that their aggregate momentum is conserved. Two of these fixes can be used to establish a temperature gradient across a simulation domain by -adding heat to one group of atoms (hot reservoir) and subtracting heat -from another (cold reservoir). E.g. a simulation sampling from the -McDLT ensemble. Note that the fix is applied to a group of atoms, not -a geometric region, so that the same set of atoms is affected wherever -they may move to. +adding heat (energy) to one group of atoms (hot reservoir) and +subtracting heat from another (cold reservoir). E.g. a simulation +sampling from the McDLT ensemble. + +If the {region} keyword is used, the atom must be in both the group +and the specified geometric "region"_region.html in order to have +energy added or subtracted to it. If not specified, then the atoms in +the group are affected wherever they may move to. Heat addition/subtraction is performed every N timesteps. The {eflux} parameter determines the change in aggregate energy of the entire