I used shorter damping constant(0.0005) and run 5000 timesteps but I am
getting same temperature( T=1.#QNAN)!!!!How should I solve this problem?
have you removed the overlapping atoms in your input?
from the input you provided, you are trying to solve the wrong problem.
axel.
Dear all
I was able to solve the problem of temperature rise infinitely.
In my sample, the left edge, there is a crack, Now I want to force it, leaving the spread.
I’ve used the fix setforce but only in the top left, little will change!!
Here is new my in.file
units metal
boundary s s p
atom_style atomic
neighbor 2.0 multi
neigh_modify every 5
#configuration
lattice bcc 2.86 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1
region box block 0 100 0 71.6 -7 7
create_box 2 box
#building region
region b block 0 100 5 32.074 -7 7 units box
group crack3 region b
region bo block 28 100 32.074 39.526 -7 7 units box
group crack2 region bo
region box1 block 0 100 39.526 66 -7 7 units box
group crack4 region box1
region crack union 3 box1 bo b units box
group boundary union crack2 crack3 crack4
group mobile subtract all boundary
group crack region crack
region layer1 block 0 100 0 5 -7 7 units box
region layer2 block 0 100 66 71.6 -7 7 units box
region union union 2 layer1 layer2 units box
create_atoms 1 region crack
create_atoms 2 region union
#force feild
mass * 56
pair_style eam/fs
pair_coeff * * Fe_2.eam.fs Fe Fe
velocity all create 300.0 87287
velocity crack2 set 0.0 0.5 0.0
velocity mobile ramp vy 0.0 0.5 y 32.074 39.526 sum yes
fix 1 all nvt temp 300.0 300.0 0.0005999
fix 2 crack setforce 0.0 NULL 0.0 region crack
#output
timestep 0.001
dump 1 all atom 500 new2.lammpstrj
thermo 200
run 5000
write_restart solidsol0.data
Many kind regards
See examples/crack/in.crack for a script that does this.
Steve
Dear all
I used the fix setforce But did not extend the length of cracks!!!
I’ve increased the number of run, But just leave the lips of crack were opened, and did not increase the length of cracks. Would you mind tell me, how can I do this work!
I hope to be able to give me some suggestions for solving this problem,
Many Thanks
I assume you looked at examples/crack/in.crack as I suggested.
To figure out the difference(s) between a script that
works and one that doesn’t (yours), is something
you have to debug. Try changing one thing at a time,
and monitor the output (thermo, viz) to see when things
change.
Steve