/PROP/TYPE14 (SOLID)

Block Format Keyword

/PROP/TYPE14 - General Solid Property Set

Description

This property set is used to define the general solid property set.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/PROP/TYPE14/prop_ID/unit_ID or /PROP/SOLID/prop_ID/unit_ID
prop_title
Isolid	Ismstr		Icpre		Inpts	Itetra	Iframe	dn
qa		qb		h
		Istrain	IHKT

To activate Sol2SPH option (Comment 24)

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
Ndir	sphpart_ID

Field	Contents	SI Unit Example
prop_ID	Property identifier (Integer, maximum 10 digits)
unit_ID	Optional unit identifier (Integer, maximum 10 digits)
prop_title	Property title (Character, maximum 100 characters)
Isolid	Solid elements formulation flag (Comments 2, 6, 8, 10, 11, 12, and 19) (Integer) = 0: default, set to value defined in /DEF_SOLID = 1: Standard 8-node solid element, one integration point. Viscous hourglass formulation with orthogonal and rigid deformation modes compensation (Belytschko). = 2: Standard 8-node solid element, one integration point. Viscous hourglass formulation without orthogonality (Hallquist). = 12: Standard 8-node solid, full integration (no hourglass). OBSOLETE - Use Isolid =17 (H8C) = 14: HA8 locking-free 8-node solid element, co-rotational, full integration, variable number of Gauss points. = 16: Quadratic 20-node solid, full integration, variable number of Gauss points. = 17: H8C Standard 8-nodes compatible solid full integration formulation 222 integration points, no hourglass = 24: HEPH 8-node solid element. Co-rotational, under-integrated (1 Gauss point) with physical stabilization.
Ismstr	Small strain formulation flag (Comments 3 to 5) (Integer) = 0: default, set to value defined in /DEF_SOLID = 1: small strain from time=0 = 2: full geometric nonlinearities with possible small strain formulation in RADIOSS Engine (/DT/BRICK/CST) = 3: simplified small strain formulation from time=0 (non-objective formulation) = 4: full geometric nonlinearities (/DT/BRICK/CST has no effect) =10: Lagrange type total strain (Comment 20) = 11: total small strain formulation from t=0
Icpre	Constant pressure formulation flag (Comments 11, 14 and 15) (Integer) = 0: default value = 1: reduced pressure integration for incompressible material () = 2: variable state between Icpre =3 and Icpre =1 in function of plasticity state for elasto-plastic behavior. = 3: no reduced pressure integration for compressible materials, like foam.
Inpts	Number of integration points (only for Isolid =14, 16) (Comment 16) (Integer) = ijk: 2 < i,j,k < 9 for Isolid =14 2 < i,k < 3, 2 < j < 9 for Isolid =16 where: i = number of integration points in r direction j = number of integration points in s direction k = number of integration points in t direction
Itetra	This formulation flag is only used by four nodes tetras (Integer) (Comment 13) =0: linear tetra 4 formulation with one integration point =1: quadratic tetra 4 formulation with six DOF per node and four integration points =3: linear tetra 4, average nodal pressure formulation for ALE formulation.
Iframe	Element coordinate system formulation flag (Comments 6, 7, and 18) (only for quad and standard 8-node bricks: Isolid =1, 2, 12, or 17) (Integer) = 0: default, set to value defined in /DEF_SOLID = 1: non co-rotational formulation = 2: co-rotational formulation needed for models with large rotations
dn	Numerical damping for stabilization (Isolid =24 only) (Comment 9) Default = 0.1 (Real)
qa	Quadratic bulk viscosity Default = 1.10 (Real) Default = 0.0 for /MAT/LAW70
qb	Linear bulk viscosity Default = 0.05 (Real) Default = 0.0 for /MAT/LAW70
h	Hourglass viscosity coefficient Not used with HEPH and fully-integration solid elements. Default = 0.10 (Real), must be 0.0 < h < 0.15
	Numerical Navier Stokes viscosity (Real)
	Numerical Navier Stokes viscosity (Real)
	Minimum time step Default = 0 (Real)
Istrain	Compute strain post-processing flag (Comment 21) (Integer) = 0: default set to value defined in /DEF_SOLID = 1: yes = 2: no
IHKT	Hourglass tangent modulus flag (Isolid =24 only) (Integer) = 0: default set to 1 = 1: elastic modulus or numerical tangent modulus estimation = 2: advanced tangent modulus estimation
Ndir	Number of particle/direction for each solid element (Integer) = 1: One particle in each direction = 2: Two particles in each direction, for a total of 8 particles = 3: Three particles in each direction, for a total of 27 particles
sphpart_ID	Part identifier describing the SPH properties for Sol2SPH (Integer)

1.	The Isolid flag is not used with 4-node and 10-node tetrahedron elements. For these elements the number of integration points is fixed (1 and 4, respectively).

2.	For Isolid =12, brick deviatoric behavior is computed using 8 Gauss points; bulk behavior is still under-integrated to avoid element locking. Those options are currently compatible with Material Laws 1, 3, 28, 29, 30, 31, 33, 34, 35 and 36.

3.	If Ismstr =1, 2, 3, or 11 (small strain flag), the strains and stresses, which are given in material laws are engineering strains and stresses. Otherwise, they are true strains and stresses.

4.	Ismstr = 1, 2 and 3, 11 (Small strain formulation) is only available for these 4-node and 8-node elements: Isolid = 1, 2, 14, 17, or 24 (standard, HA8, and HEPH solids). Isolid = 12 (8 Gauss points formulations) only use Ismstr = 4.

5.	The RADIOSS Engine option /DT/BRICK/CST will only work for brick property sets with Ismstr = 2.

The flag Ismstr = 10 is only compatible with some material laws using total strain formulation (for example, Laws 1, 38, 42, 69 and 82). The Left Cauchy-Green strain is used for /MAT/LAW1 (ELAST), /MAT/LAW38 (VISC_TAB) and /MAT/LAW42 (OGDEN), otherwise, the Green-Lagrange strain.

Ismstr = 11 has been developed for Law 70 (foam), it is only compatible with material laws using engineering total strain (for example, Laws 38 and 70). Generally more stable results can be obtained when Ismstr =1.

For Isolid = 1, 2, 12, or 17 and Iframe = 2 (Co-rotational formulation), the stress tensor is computed in a co-rotational coordinate system. This formulation is more accurate if large rotations are involved, at the expense of higher computation cost. It is recommended in cases of elastic or visco-elastic problems with important shear deformations.

7.	Iframe= 2 (Co-rotational formulation) is compatible with 8-node bricks and with quad elements (bi-dimensional and axisymmetric analysis).

8.	Isolid = 24 (HEPH) solid elements: hourglass formulation is similar to Ishell = 24 (QEPH) shell elements.

9.	Numerical damping dn is only used in hourglass stress calculation for Isolid = 24 (HEPH) solid elements. If dn uses the same value, as h (hourglass viscosity coefficient for Isolid =1 or 2), the damping value is 2/3*1.0-3 times than Isolid =1 or 2.

10.

Isolid = 14 (HA8): Locking-free general solid formulation, co-rotational. The number of Gauss points is defined by Inpts flag: for example, combined with Inpts = 222 provides an 8 Gauss integration point element, similar to Isolid = 12 and 17. Isolid = 14 (HA8) formulation is compatible with all material laws.

11.	An Isolid = 14 (HA8) solid element should use under-integrated pressure for uncompressible material (Icpre = 1 in case of hyperelastic or visco-elastic uncompressible law; Icpre = 2 in case of elasto-plastic law).

12.	For Isolid = 17 (H8C), brick deviatoric behavior (is the same as Isolid = 12) (Comment 2). It is computed using 8 Gauss points; the bulk behavior can be chosen with Icpre. It is compatible with all solid type material laws.

13.	Itetra = 1 is not compatible with small strain formulation Ismstr = 1, 2, or 3.

14.	Flag Icpre is only used for Isolid=14 (HA8), Isolid = 17 (H8C), and Isolid = 24 (HEPH).

•	Icpre = 3 is the default value for Isolid = 14 (HA8) and Isolid = 24 (HEPH)

•	Icpre = 1 is the default for Isolid = 17 (H8C).

15.	Flag Icpre = 2 is only available for elasto-plastic material law.

16.	For quadratic 20 node solid, the number of integration points is defined by the Inpts flag. Valid values are 2 or 3 in r and t directions and 2 to 9 in s direction. The recommended value is Inpts = 222.

17.	For post-processing solid element stress, refer to /ANIM/BRICK/TENS/STRESS for animation and /TH/BRIC for plot files.

18.	In plot and animation files, stress tensor is attached to the co-rotational frame.

19.	The hourglass formulation is viscous for Isolid = 0, 1, or 2.

20.	The flag Ismstr = 10 is only available with 8 node solid element (not available with Isolid = 12, which is obsolete) and 4 node solid tetra elements (if Itetra ≠ 1).

21.	The Istrain flag is not used with Material Laws 14, 24 and Material Laws greater than 28. For these materials, the strains for post-processing are always computed.

22.	The numerical Navier Stokes viscosity model is available for all material laws. Please note that the output viscosity stress is available just for users law and Isolid =1 (In time history output the viscosity stress is added in the stress).

23.

It is recommended to use IHKT = 2 with HEPH and Lagrange type total strain, Ismstr = 10 for foam or rubber materials like laws 38, 42, 69, and 82. Also, use this value with LAW24, if the damage effect is taken into account in hourglass stress compute. For elasto-plastic type laws, IHKT = 2 will get a tighter yield stress criterion for hourglass stress compute.

24.

If Sol2SPH is activated, solids are turned into SPH particles, if the solid is deleted (failure criteria, material law failure or time step criteria). The number activated of SPH particles depends on parameter Ndir. The particles properties are computed using the sphpart_ID part number. This option is only compatible with Isolid = 1, 2, or 24, Iframe = 1 or 2, and with non-degenerated 8 nodes brick elements (no penta or tetra, even under degenerated form).

25.	4-nodes tetrahedron are compatible with the ALE formulation only if using Itetra = 0 or 3. The latest being recommended to reduce shear locking.

26.	Starting with version 2017, Lagrangian elements whose volume becomes negative during a simulation will automatically switch strain formulations to allow the simulation to continue. When this occurs, a WARNING message will be printed in the Engine output file. The following options are supported.

Element Type	Element Formulation	Strain Formulation	Negative Volume handling method
/BRICK /TETRA4 (Itetra = 0) /TETRA10	Isolid =1, 2, 14, 17, 24	Full geometric nonlinearities Ismstr = 2, 4	Switch to small strain using element shape from cycle before negative volume.
/BRICK /TETRA4 (Itetra = 0) /TETRA10	Isolid =1, 2, 14, 17, 24	Lagrange type total strain Ismstr = 10	Lagrange total strain with element shape at time=0.0

/PROP/TYPE14 (SOLID)

/PROP/TYPE14 (SOLID)

/PROP/TYPE14 (SOLID)

See Also: