Greetings,
I'm developing a flow simulation in a bed with gravel. The simulation contains 800k particles in a 2.0x0.8x0.2 bed, but as the simulation progresses the RAM memory consumption increases a lot, to the point of causing an error (signal 9). I intend to simulate a flowtime of approximately 500s. Could someone give me tips to reduce this memory consumption? I tried to implement the fix freeze , but the particles didn't freeze as I thought, I tried to implement the neigh_modify exclude after the particles settled, but it wasn't enough.
The script was pasted below:
atom_style sphere #granular #sphere
atom_modify map hash sort 1000 0.25
boundary f f f
newton off
echo both
communicate single vel yes
processors 2 1 1
units si
#Declair Domain
region reg block -0.1 0.9 -0.1 2.1 -0.1 0.60 units box
region regGM block 0.01 0.79 0.01 1.99 0.01 0.49 units box
create_box 1 reg regGM
neighbor 0.0 bin #I tryed use the nsq but simulation don't run
neigh_modify binsize 0.0 #I tryed to increse the binsize but simulation don't run if a change it
neigh_modify every 1
neigh_modify delay 0
neigh_modify page 1000
neigh_modify one 100
###Setup
#Material properties required for new pair styles
fix m1 all property/global youngsModulus peratomtype 5.e6
fix m2 all property/global poissonsRatio peratomtype 0.45
fix m3 all property/global coefficientRestitution peratomtypepair 1 0.3
fix m4 all property/global coefficientFriction peratomtypepair 1 0.71
fix m5 all property/global k_finnie peratomtypepair 1 1.0
#Physics
#pair_style none
pair_style gran model hertz tangential history #Hertzian without cohesion
pair_coeff * *
#distributions for insertion
fix pts5 all particletemplate/sphere 15485989 atom_type 1 density constant 2900 radius constant 0.004 #8
fix pdd1 all particledistribution/discrete 32452843 1 pts5 1.00
# walls
fix xwalls1 all wall/gran model hertz tangential history primitive type 1 xplane 0.0
fix xwalls2 all wall/gran model hertz tangential history primitive type 1 xplane 0.8
fix ywalls1 all wall/gran model hertz tangential history primitive type 1 yplane 0.0
fix ywalls2 all wall/gran model hertz tangential history primitive type 1 yplane 2.0
fix zwalls1 all wall/gran model hertz tangential history primitive type 1 zplane 0.0
fix zwalls2 all wall/gran model hertz tangential history primitive type 1 zplane 0.8
###Detailed Settings
#Integration
fix integrate all nve/sphere
#Gravity
fix grav all gravity 9.81 vector 0.0 0.0 -1.0
#Timestep
timestep 1e-04
#ThermoDynamic output
compute 1 all erotate/sphere
thermo_style custom step atoms ke c_1 vol
thermo 0
thermo_modify lost ignore norm no
compute_modify thermo_temp dynamic yes
#Insert particle bed
fix meio all insert/pack seed 49979693 distributiontemplate pdd1 &
insert_every once overlapcheck yes all_in no vel constant 0.0 0.0 0.0 &
region regGM volumefraction_region 0.29
#settle of granular media
dump dmpparticles all custom/vtk 10000 post/insert_*.vtk id type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius mass diameter density
write_restart CFD/post/restart/liggghts.restart
run 20000
pair_style none
#fix top all mesh/surface file ../DEM/meshes/top.stl type 1
#fix geometry all wall/gran model hertz tangential history mesh n_meshes 1 meshes top
group particle type 1
unfix meio
#freeze the media
fix freezed particle freeze
neigh_modify exclude type 1 1
#Enable coupling
fix cfd all couple/cfd couple_every 0 mpi
fix cfd2 all couple/cfd/force
run 0