Friday, May 4, 2018

LAMMPS Input File RUNNING


Here I am explaining about the things one needs to know just to run the input file with varying the star data file and strain rate.

To run the lammps input file: (FOR WINDOWS)
1.       Put the input file (i.e. in.sp.0.002.mp) inside a folder. Remember the input file name will always start with “in.” . You can put whatever name you want after that. I tried to use the strain rate value to remember the strain rate value I used inside.
2.       Copy the star data file and paste inside the same folder.
3.       Copy the lammps executable (lmp_serial) and paste into the same folder with input file.
4.       Copy the libOpenCL.dll file and paste it to the same folder location.
5.       Now open the “Run” command
6.       Type “cmd” and hit “enter”
7.       A command prompt will pop up
8.       Navigate to the folder where you have pasted all the above files
9.       Then type lmp_serial<input_file_name (ie. Lmp_serial<in.sp.0.002.mp) and hit “Enter”. The simulation will start running.

(To run in LINUX/Mac):
1.       Same procedure. (except it does not need the .dll file)
2.       In the command prompt after navigating to the desired folder instead of typing lmp_serial<input_file name you just have to type ./lmp_serial<input_file_name. Here you have to create your executable by yourself and you could name it as you like. (I named the executable same as the Windows for remembering easily).
“DONE”

The input file has two things to change that would cause different different output.
1.       Star file name
2.       Strain rate values
STAR FILE NAME
The star data file is generated by Python script and it contains the coordinates of star particles.
The input file Line number 10 (link attached) has command :
read_data  data.star fix molprop NULL Molecules
here data.star is the star data file and the same named star data file should be present in the same folder with input file. I you want to change the name of star data file you have to change in both place (in folder and inside the input file).

STRAIN RATE VALUES
In the line number 118 has the fllowing command:
variable srate1 equal 0.002
the value 0.002 is the strain rate. (I used this value to name input file, remember !)

https://drive.google.com/file/d/1xNu5pZfmT_G8MrzPWFIGuErbAqmthZxP/view?usp=sharing