View source for Code: WARP

__NOTOC__

{|
|- 
! Name 
| Atomistic Stress Simulator (WARP)
|-
! Status 
| production version available
|-
! Release Date 
| 2001
|-
! Authors 
| [mailto:sjplim@sandia.gov Steve Plimpton (Sandia National Laboratory)]
|-
! Contact 
| [mailto:sjplim@sandia.gov Steve Plimpton (Sandia National Laboratory)], [mailto:mbaskes@ucsd.edu Michael Baskes (UC San Diego)]; at CAVS: [mailto:bj48@cavs.msstate.edu Bohumir Jelinek], [mailto:moitra@cavs.msstate.edu Amitava Moitra] 
|-
! License
| &copy; Sandia National Laboratory
|-
! Repository 
| The code is distributed by its authors. (CAVS users: see [http://sparrow-01-14.hpc.msstate.edu/incavswiki/index.php/Code:_WARP the CAVS intranet]).
|-
! Documentation
| [[Media:WARP-Overwiev.pdf‎|WARP Overwiew.pdf]]
|-
! Known problems
| None
|}

'''Description:'''  WARP is a parallel molecular
dynamics simulation code for modeling stress and strain in materials using
embedded atom method (EAM) and Lennard-Jones (LJ) potentials.  It is
written in F90 and performs message-passing via MPI calls.   
This code is copyrighted property of Sandia National Laboratories.  Please contact the author(s) for a copy of the source
code or further information.

''To report bugs, problems or to make comments please use the discussion tab above.''

[[Multiscale_Simulations| back to the Multiscale Simulations codes home]]


== Compiling WARP ==
Type make to see a list of supported machines.  You can add a new
machine to the list by creating an appopriate Makefile.machine file
and adding the new machine to the target list in Makefile.  The
"serial" target does not require MPI be installed on your workstation.
The other targets require MPI.

If the -DCRACK compiler flag is set in Makefile.machine, Warp adds the
command "no neighbor" that enables crack propagation simulations.


== Running WARP ==
Warp is run by redirecting an input script to stdin, e.g.

warp_machine < in.file
mpirun -np 16 warp_machine < in.file 

== The Structure of the WARP Input File ==

The input script consists of a series of single-line commands.  Most
of the input commands take one or more parameters.  The keyword for
each command should begin in the leftmost column and all characters in
the command should be in lower-case.  Parameters can be separated by
arbitrary numbers of spaces and/or tabs (so long as the command fits
on one line).

The order of commands for performing a simulation are as follows:

<pre>
(1) set parameters			   only those different than defaults
(2) create box				   mandatory

Either:
  (3) orient and origin                    as needed
  (4) select region			   mandatory
  (5) define cutout			   as needed
  (6) create atoms			   mandatory (loop on 3-6 as desired)
  (7) check for atom overlap		   as needed
  (8) select and create types and eltypes  as needed
  (9) select and create vels		   as needed
Or:
  (3) scale read                           as needed
  (4) type translate                       as needed
  (5) read atoms			   mandatory
  (6) check for atom overlap		   as needed
  (7) select and create types and eltypes  as needed
  (8) select and create vels		   as needed
Or:
  (3) read restart                         mandatory

(10) select and create fixes		   as needed
(11) apply temp and pres controls	   as needed

(12) run				   can perform multiple times,
					      changing parameters as desired
Or:
(13) relax				   minimize potential energy
</pre>

Note that several parameters must be defined (if not default) before
the global simulation box is created and memory is allocated in step
(2).  These settings include units, extra memory, potential, neighbor,
processor grid, periodicity, and lattice.

Please refer to [[Media:WARP-Overwiev.pdf‎|WARP Overwiew.pdf]] for a complete list of valid Warp inputs and the "type"
of parameters that should be used.

== Example Input Files ==

=== in.ni100 ===

Summary: Minimize potential energy to compute energy of [100] surface of nickel

Features demonstrated:
* EAM potential
* read atoms (from file snap.ni100)
* relax

[[Code: WARP ni100| view the input file]]

=== in.shear.fixed ===

Summary: Shear block of atoms

Features demonstrated:
* EAM potential
* create atoms
* create vels, ramp
* create fixes, xyz
* temp control
* temp adjust, xyz
* snapshot
* snap column
* snap thresh

[[Code: WARP shear.fixed| view the input file]]

=== in.sic_liquid ===

Summary: Amorphous Si-C system

Features demonstrated:
* MEAM potential (with multiple atom types)
* snapshot
* read atoms (from file snap.sic_liquid)

[[Code: WARP sic_liquid| view the input file]]

=== in.tensile_meam ===

Summary: Void growth under uniaxial tensile strain

Features demonstrated:
* MEAM potential
* define cutout
* create atoms
* create fixes, xyz
* create vels, thermal
* create vels, ramp
* temp control
* temp adjust, ramp
* restart
* snapshot
* snap column
* snap thresh
* diagnostic (tensile_meam)

[[Code: WARP tensile_meam| view the input file]]

=== in.torsion ===

[[Code: WARP torsion| view the input file]]

[[Category: Tutorial]]
[[Category: WARP]]