Dear LAMMPS users
I want to make spatial temperature profile to certain direction(z direction) for my simulation system.
To do this, at first, I set the z directional regions like bins with region command and set the dynamic groups of these and tried to compute temperatures.
However, it didn’t work because of too many groups error.
I edited the maximum number of group larger than 32 in group.cpp and tried again, but it didn’t work again.
Next, I used compute(temp/profile) command and fix(ave/spatial) command like as below,
compute mytemp all temp/profile 1 1 1 xyz 1 1 20
fix tempf all ave/spatial 100 1 1000 c_mytemp file temp.profile
but it didn’t work with illegal fix ave/spatial command.
How can I solve the problem to make temperature profile with compute and fix command?
kind regards,
Woo Cheol Jeon
Do you expect your system to have non-zero streaming velocities? If you’re not looking at a flowing system, you probably don’t need temp/profile.
If not, and if you’re using a recent (after this summer), version of LAMMPS, you need to use compute ke/atom to get your “per-atom” temperature, then use compute chunk/atom and fix ave/chunk to average it as you like.
If you’re using an older version of LAMMPS, you can use compute ke/atom and fix ave/spatial.
Dear Niall Jackson
Thank you for your kind response.
I need to see z-directional sptial temperature every steps.
My system is Al/Ni pure metal bilayer so it is not a flowing system.
If I use compute ke/atom with compute chunck/atom and fix ave/chunk, can I export temperature information for every bins and every steps?
kind regards,
Woo Cheol Jeon
fix tempf all ave/spatial 100 1 1000 c_mytemp file temp.profile
but it didn’t work with illegal fix ave/spatial command.
B/c the syntax is incorrect - see the doc page. You don’t have
dim origin delta.
Steve
If I use compute ke/atom with compute chunck/atom and fix ave/chunk, can I export temperature information for >every bins and every steps?
If by “export” you mean write the results to a file, then yes.
See the “file” option on the fix ave/chunk command.
Steve