Either memory_type should be set to -updated, -total, -updated_without_rotation. See the theoretical part for some explanation.
For a total Lagrange solid the input file may look like
...
materi_velocity
materi_displacement
materi_strain_total
materi_stress
end_initia
...
group_materi_memory 0 -total
group_materi_elasti_young 0 ...
...
end_data
For an updated Lagrange solid the input file may look like
And use -updated_without_rotation instead of -updated if the rotations are small and you want to save some CPU time.
...
materi_velocity
materi_stress
end_initia
...
node 1 ...
node 2 ...
...
group_materi_memory 0 -updated
group_materi_elasti_young 0 ...
...
end_data
For a fluid the input file may look like
The options_mesh record causes an Eulerian calculation.
...
materi_velocity
materi_stress
end_initia
...
options_mesh -fixed_in_space
...
node 1 ...
node 2 ...
...
group_materi_memory 0 -updated_without_rotation
group_materi_viscosity 0 ...
group_materi_elasti_compressibility 0 ...
...
end_data
The index specifies the element_group, see element_group.