It is not really clear what you mean. If every simulation has its own input
file and you want them to run independently of each other, you can use gnu
parallel or xargs for that.
You can also simply use & to put each simulation in the background.
For example:
cd directory1
lmp_mpi -in run.in &
cd ..
cd directory2
lmp_mpi -in run.in &
cd ..
cd directory3
lmp_mpi -in run.in &
cd ..
:
cd directory9
lmp_mpi -in run.in &
cd ..
You can type these commands into the shell, or put these 9 commands
in a file (eg "script.sh"), make it executable (eg "chmod 755
script.sh"), and run it (eg "./script.sh &").
&
"With & the process starts in the background, so you can continue to
use the shell and do not have to wait until the script is finished. If
you forget it, you can stop the current running process with Ctrl-Z
and continue it in the background with bg (or in the foreground with
fg). For more information, see job control"
http://unix.stackexchange.com/questions/86247/what-does-ampersand-mean-at-the-end-of-a-shell-script-line
http://hacktux.com/bash/ampersand
Of coarse, if you want each simulation to run using multiple
processors, then replace each "lmp_mpi -in run.in" line with something
like "mpirun -np 2 lmp_mpi -in run.in".
...and it's also probably a good idea to use "nice", for example:
nice -n 15 ./script.sh
https://en.wikipedia.org/wiki/Nice_(Unix)
Cheers
Andrew
P.S. If you are logging in to a remote computer to run your
simulations, you may want to insert "nohup" at the beginning of each
line containing "lmp_mpi".
https://en.wikipedia.org/wiki/Nohup