/DEF_SHELL

Block Format Keyword Used to set default values for certain parameters in all shell properties, but options could still be changed in each property set input and in this case, the latter will prevail.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/DEF_SHELL
Ishell Ismstr Ithick Iplas Ioffset Ish3n I_drill

Definition

Field Contents SI Unit Example
Ishell Shell element formulation flag.
= 0
Set to 1 or 24.
= 1 Default, if /IMPLICIT is not used in deck.
Q4, visco-elastic hourglass modes orthogonal to deformation and rigid modes (Belytschko).
= 2
Q4, visco-elastic hourglass without orthogonality (Hallquist).
=3
Q4, elasto-plastic hourglass with orthogonality.
= 4
Q4 with improved type 1 formulation (orthogonalization for warped elements).
= 12
QBAT shell formulation.
= 24 Default, if /IMPLICIT is used in deck.
QEPH shell formulation.

(Integer)
Ismstr Shell small strain formulation flag.
= -2
Automatically set the best value according element type and material law and overwrite the value defined in any shell properties.
= -1
Automatically set the best value according element type and material law.
= 0
Set to 2.
= 1
Small strain from time = 0.
(new formulation compatible with all other formulation flags).
= 2 (Default)
Full geometric nonlinearities with possible small strain formulation activation in Radioss Engine (option /DT/Eltyp/Keyword3/Iflag).
= 3
Old small strain formulation (only compatible with Ishell =2).
= 4
Full geometric nonlinearities (in Radioss Engine, option /DT/SHELL/CST has no effect).

(Integer)
Ithick Shell resultant stresses calculation flag.
= -2
Automatically set the best value according element type and material law and overwrite the value defined in any shell properties.
= -1
Automatically set the best value according element type and material law.
= 0
Set to 2.
= 1
Thickness change is taken into account.
= 2 (Default)
Thickness is constant.

(Integer)
Iplas Shell plane stress plasticity flag.
= -2
Automatically set the best value according element type and material law and overwrite the value defined in any shell properties.
= -1
Automatically set the best value according element type and material law.
= 0
Set to 1 or 2.
= 1 Default, if /IMPLICIT is used in deck.
Iterative projection with three Newton iterations.
= 2 Default, if /IMPLICIT is not used in deck.
Radial return

(Integer)
Ioffset Flag to consider shell offset in all compatible contact interfaces. 3
= 0 (Default)
Set to 2.
= 1
Shell offset is activated in all compatible contact interfaces in the model.
= 2
No shell offset in the contact. Gap is equally distributed around the shell mesh.

(Integer)
Ish3n 3-node shell element formulation flag.
= 0
Set to 2.
=1
Standard triangle (C0).
= 2 (Default)
Standard triangle (C0) with modification for large rotation.
= 30
DKT18.
= 31
DKT_S3, which based on DTK12 of BATOZ (refer to Element Library in the Theory Manual).

(Integer)
I_drill Drilling DOF stiffness flag.
=0
Set to 2.
= 1 Default, if /IMPLICIT is used in deck.
Yes.
= 2 Default, if /IMPLICIT is not used in deck.
No.

(Integer)

Comments

  1. This card is read only once. Only the first card /DEF_SHELL written in the model is used. The other card /DEF_SHELL is ignored.
  2. Refer to the comments in /PROP/TYPE1 (SHELL) for more information about these input options.
  3. Flag Ioffset to consider shell offset in the contact interface is compatible with the following contact interfaces:
    • /INTER/TYPE7
    • /INTER/TYPE10
    • /INTER/TYPE11
    • /INTER/TYPE14
    • /INTER/TYPE15
    • /INTER/TYPE18
    • /INTER/TYPE19
    • /INTER/TYPE21
    • /INTER/TYPE23
    • /INTER/TYPE24
    • /INTER/TYPE25

When Ioffset =1, shell offset is applied to all compatible contact interfaces defined in the model.