Istf

Interface stiffness definition flag (Comment 5 in /INTER/TYPE7). For SPH, only Istf =0 and =1 are available.

(Integer)

= 0: default, set to 1000

= 1: Stfac is a constant stiffness value

= 2, 3, 4 and 5: Stfac is a stiffness scale factor and the interface stiffness is computed from both master and slave characteristics

= 1000: Stfac is a stiffness scale factor and interface stiffness is computed based only on the master side characteristics

Igap

Gap/element option flag (Comment 13 in /INTER/TYPE7)

(Integer)

= 0: default, set to 1000

= 1: variable gap varies according to the characteristics of the impacted master surface and the impacting slave node

= 2: variable gap + gap scale correction of the computed gap

= 3: variable gap + gap scale correction of the computed gap + size of the mesh taken into account to avoid initial penetrations.

= 1000: constant gap; equal to the minimum gap Gapmin (default)

Ibag

Airbag vent holes closure flag in case of contact

(Integer)

= 0: default, set to 1000

= 1: closure

= 1000: no closure (default)

Idel

Node and segment deletion flag

(Integer)

= 0: default, set to 1000

= 1: when all the elements (4-node shells, 3-node shells, solids) associated to one segment are deleted, the segment is removed from the master side of the interface. It is also removed in case of explicit deletion using RADIOSS Engine keyword /DEL in the Engine file.

Additionally, non-connected nodes are removed from the slave side of the interface.

= 2: when a 4-node shell, a 3-node shell or a solid element is deleted, the corresponding segment is removed from the master side of the interface. It is also removed in case of explicit deletion using RADIOSS Engine keyword /DEL in the Engine file.

Additionally, non-connected nodes are removed from the slave side of the interface.

= -1: same as =1, except non-connected nodes are not removed from the slave side of the interface.

= -2: same as =2, except non-connected nodes are not removed from the slave side of the interface.

= 1000: no default (default)

Note: Idel =1 and -1 has a higher CPU cost when compared with Idel =2 and -2.

Irem_gap

Flag for deactivating slave nodes if element size < gap value, in case of self-impact contact (Comment 26)

(Integer)

= 0: default, set to 1

= 1: no deactivation of slave nodes (default)

= 2: deactivation of slave nodes

Irem_i2

Flag for deactivating the slave node, if the same contact pair (nodes) has been defined in interface type 2.

= 0: default,
       set to 1, if /IMPLICIT is defined;

       set to 3 for explicit solution

= 1: with deactivating (default for implicit solution (if /IMPLICIT is defined)

= 3: without deactivating (default for explicit solution)

Inacti

Deactivation flag of stiffness in case of initial penetrations (Comment 15 in /INTER/TYPE7)

(Integer)

= 0: default, set to 1000

= 1: deactivation of stiffness on nodes

= 2: deactivation of stiffness on elements

= 3: change node coordinates to avoid initial penetrations

= 5: gap is variable with time and initial gap is adjusted as follows:

, where P0 is the initial penetration

= 6: gap is variable with time but initial gap is adjusted as follows (the node is slightly depenetrated):

= 1000: no action (default)

Iform

Friction penalty formulation type (Comments 23 through 25 in /INTER/TYPE7)

(Integer)

= 0: default, set to 1

= 1: viscous (total) formulation (default)

= 2: stiffness (incremental) formulation