dump force on wall

raguelmoon's picture
Submitted by raguelmoon on Thu, 10/27/2011 - 06:20

Hi,
Is there any way to dump force (weight) on wall of container due to all particles (if I dont want to use mesh)?
Thanks in advance,
Ram

Forums:

prasantud | Thu, 10/27/2011 - 09:43

fix wall/gran/
store_force value = 'yes' or 'no'
yes, no = determines if the wall force exerted on the particles is stored in a fix property/atom with id force_(ID), where (ID) is the id of the fix wall/gran command.

raguelmoon's picture

raguelmoon | Thu, 10/27/2011 - 16:18

Hi,
Thanks for reply. But I couldnt find the usage of this command in doc pages. Could you tell me how to use this command? I want to calculate force of granular particles on the wall.
Thanks,
Ram

Ram

raguelmoon's picture

raguelmoon | Thu, 10/27/2011 - 19:33

Hi,
Thanks I found it. But I have confusion about defining it in property/atom and writing an output. Is there any tutorial example?
It is written in doc pages as: "....the per-atom wall force can be accessed by the various output commands via f_force(ID)1, f_force(ID)2, f_force(ID)3. (ID) is the id of the fix wall/gran command. " So I wrote output as "f_force(zwall)1" and "f_force_zwall[1]", zwall being my wall/gran id, then it gives error.
Thanks,
Ram

Ram

raguelmoon's picture

raguelmoon | Fri, 10/28/2011 - 07:53

Hi,
Thanks all. Now it works but I am not sure if is a correct way of dumping force at bottom wall. My script is like this:

...
..
fix zwall all wall/gran/hertz/history 1 0 zplane -0.2 NULL 1 store_force yes
...
...
compute p all reduce sum f_force_zwalls[1] f_force_zwalls[2] f_force_zwalls[3]
....
...
fix forceAtBottom all ave/time 50 2 100 c_p[1] c_p[2] c_p[3] file weight.profile
...
...

Thanks,
Ram

Ram