ICODE-ADC/lammps
4
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

make description of eflux as a variable less convoluted

Browse Source
This commit is contained in:
Axel Kohlmeyer
2020-04-22 08:13:27 -04:00
parent 73bf1874c5
commit fc10e885b2
1 changed files with 16 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
doc/src/fix_heat.rst
View File

@ -47,16 +47,22 @@ and the specified geometric :doc:`region <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 can be specified as a numeric constant or as a variable (see
below). If it is a numeric constant or equal-style variable which
evaluates to a scalar value, then the *eflux* determines the change in
aggregate energy of the entire group of atoms per unit time, e.g. in
eV/psec for :doc:`metal units <units>`. In this case it is an
"extensive" quantity, meaning its magnitude should be scaled with the
number of atoms in the group. Note that since *eflux* has per-time
units (i.e. it is a flux), this means that a larger value of N will
add/subtract a larger amount of energy each time the fix is invoked.
Heat addition/subtraction is performed every N timesteps.
The *eflux* parameter can be specified as a numeric constant or as an
equal- or atom-style :doc:`variable <variable>`. If the value is a
variable, it should be specified as v_name, where *name* is the variable
name. In this case, the variable will be evaluated each timestep, and
its current value(s) used to determine the flux.
If *eflux* is a numeric constant or equal-style variable which evaluates
to a scalar value, then *eflux* determines the change in aggregate energy
of the entire group of atoms per unit time, e.g. in eV/psec for
:doc:`metal units <units>`. In this case it is an "extensive" quantity,
meaning its magnitude should be scaled with the number of atoms in the
group. Note that since *eflux* also has per-time units (i.e. it is a
flux), this means that a larger value of N will add/subtract a larger
amount of energy each time the fix is invoked.
.. note::
@ -71,12 +77,6 @@ the energy flux for a single atom, again in units of energy per unit
time. In this case, each value is an "intensive" quantity, which need
not be scaled with the number of atoms in the group.
As mentioned above, the *eflux* parameter can be specified as an
equal-style or atom_style :doc:`variable <variable>`. If the value is a
variable, it should be specified as v_name, where name is the variable
name. In this case, the variable will be evaluated each timestep, and
its value(s) used to determine the flux.
Equal-style variables can specify formulas with various mathematical
functions, and include :doc:`thermo_style <thermo_style>` command
keywords for the simulation box parameters and timestep and elapsed