output indent force by fix indent command

Dear all,

I use the commands to output the indent force in y direction as follow:

variable y equal vdisplace(-220.0,0.1)
fix 33 all indent 1000.0 cylinder z 400.0 v_y 200.0 units box
fix 88 all ave/time 1 100 1000 f_33[2] file indentforce.txt

I find that the indent force is not always zero when the indenter is far from the material. Sometimes it is zero and sometimes it is not zero. I don’t know what happened. Does the command I adopt is wrong?

Sincerely look forward to your help!
Thank you very much!

Best Regards,


I suggest you skip the fix ave/time (for now) and simply
print out f_33[2] with thermo output every step and see
if the values are what you expect.