peridynamics / method eps


I launched a simulation of a tensile test on a tiny beam. But I got only 0 for the average stress and for each step. I think that i have a fracture very soon but actually, I tried with very small time step without results and i work already with the smallest units. Moreover, I display on matlab the atomis distribution at the end and at the beginning of the beam and it seems that the each extremity isn´t linked with the middles_atoms, as the fracture existed before the try.I checked the units of my parameters many times and they are good.

Maybe I forgot some information to add at my input file ?

Thanks you for your consideration

Simon Bourreau

Here is my INPUT file :

units nano
dimension 3
boundary s s s
atom_style peri
atom_modify map array
neighbor 0.001 bin
lattice sc 0.3615

#define all the parts

region beam block 0 36.15 0 2.169 0 2.169 units box
create_box 1 beam
create_atoms 1 region beam

region leftbc block 0 1.0845 0 2.169 0 2.169 units box
group leftbc region leftbc

region rightbc block 35.0655 36.15 0 2.169 0 2.169 units box
group rightbc region rightbc

group boundary union leftbc rightbc

group middle_atoms subtract all boundary

pair_style peri/eps

pair_coeff * * 37000 27750 1.0846 30 0.25 40

set group all density 8960e-6

set group all volume 0.047241

compute peratom middle_atoms stress/atom NULL

compute sigmaxx middle_atoms reduce sum c_peratom[1]

variable sigmavolxx equal c_sigmaxx/(0.94*vol)

fix 1 rightbc move linear 1.8075 0 0 units box

fix 2 leftbc move linear -1.8075 0 0 units box

timestep 0.005e-3 #0.005

thermo 100
thermo_style custom step v_sigmavolxx lx temp ke

dump 1 all custom 50000 peri_6_nano_eps_res.txt id x y z
dump_modify 1 append yes

run 50000