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elements:blz3d [2019/03/01 14:41]
admin created
elements:blz3d [2021/12/17 16:34] (current)
laurent
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-====== BLZ3D ======+====== BLZ3D/​BWD3D ​======
  
 +===== Description =====
 +
 +{{ :​elements:​blz3d.png?​300|}}
 +8 node large strain volumetric element with hourglass and locking control. \\
 +
 +Implemented by: Zhu Yongyi, January 1992 \\
 +Improved by: Laurent Duchêne and Pierre de Montleau, August 2004 (BWD3D version)
 +
 +Type: 22
 +
 +Prepro: BLZ3DA.F \\
 +Lagamine: BLZ3DB.F, BWD3DB.F\\
 +
 +===== Input file =====
 +^TITLE (A5)^^
 +|TITLE ​ | '​BLZ3D'​ in columns 1 to 5|
 +^CONTROL (5I5)^^
 +|NELEM ​ | Number of elements |  ​
 +|INDPP ​ |= 0 if no weight (or no density if NTANA=-1)|
 +|:::    |= 1 if weight taken into account (or density)|
 +|INSHE ​ |= 0 for automatic calculation of shear locking parameter|
 +|:::    |= 1 if shear coefficient taken into account (see below)|
 +|:::    |= -1 for use of element BWD3D (only 1 integration point)|
 +|ILOAX ​ |= 0 for global axis computation \\ ☛ Objectivity must be verified in the material law (with Jaumann correction)\\ ☛ No rotation of material axes|
 +|:::|< 0 for computation with constant and symetrical velocity gradients \\ pseudo local axes : use of local axes on the time step but no evolution of the local axes on the following time step \\ ☛ Objectivity is verified \\ ☛ No rotation of material axes|
 +|:::|> 0 for computation with local axes \\ ☛ Objectivity is verified \\ ☛ Rotation of material axes|
 +|:::|units: \\ = 1 for rotations incorporated in local tangent matrix :!: **Not available** \\ = 2 apply final rotation to local tangent matrix \\ = 3 apply initial rotation to local tangent matrix \\ = 4 compute tangent matrix through global perturbation method|
 +|:::|tens (only for ILOAX>​0):​ \\ = 0 for local axes e<​sub>​1</​sub>,​ e<​sub>​2</​sub>,​ e<​sub>​3</​sub>​ initially parallel to global axes e<​sub>​x</​sub>,​ e<​sub>​y</​sub>,​ e<​sub>​z</​sub>​ \\ = 1 for local axes e<​sub>​1</​sub>,​ e<​sub>​2</​sub> ​ given (and e<​sub>​3</​sub>​=e<​sub>​1</​sub>​∧e<​sub>​2</​sub>​) \\ = 2 for local axes e<​sub>​1</​sub>,​ e<​sub>​2</​sub> ​ initially in the plane (e<​sub>​x</​sub>,​ e<​sub>​y</​sub>​) forming an angle θ with e<​sub>​x</​sub>,​ e<​sub>​y</​sub>​ (and e<​sub>​3</​sub>​=e<​sub>​1</​sub>​∧e<​sub>​2</​sub>​)\\ = 3 same as 1 with different local axes for each element \\ = 4 same as 2 with different local axes for each element|
 +|ISIG0| = 0 if no initial stresses|
 +|:::| = 1 for input of initial stresses|
 +^CONSIDERATION OF WEIGHT (4G10.0) \\ Only if INDPP = 1 ^^
 +|WSPE(1)| = specific weight in X direction|
 +|WSPE(2)| = specific weight in Y direction|
 +|WSPE(3)| = specific weight in Z direction|
 +|WSPE(4)| = density| ​
 +^CONSIDERATION OF SHEAR LOCKING (1G10.0) \\ Only if INSHE = 1 ^^
 +|PARSHE| Shear locking coefficient ∈ [0,1] \\ - close to 0: avoid shear locking but higher risk of hourglass modes (use for thin elements in flexion) \\ - close to 1: avoid hourglass modes but higher risk of shear locking (use for cubic elements in shear)|
 +^INITIAL ORIENTATION OF LOCAL AXES (6G10.0) \\ Only if tens of ILOAX = 1 or 3 \\ (only one line if tens of ILOAX = 1, repeated for each element if tens of ILOAX = 3) ^^
 +|e<​sub>​1</​sub>​(x)|coordinate of e<​sub>​1</​sub>​ along e<​sub>​x</​sub>​|
 +|e<​sub>​1</​sub>​(y)|coordinate of e<​sub>​1</​sub>​ along e<​sub>​y</​sub>​|
 +|e<​sub>​1</​sub>​(z)|coordinate of e<​sub>​1</​sub>​ along e<​sub>​z</​sub>​|
 +|e<​sub>​2</​sub>​(x)|coordinate of e<​sub>​2</​sub>​ along e<​sub>​x</​sub>​|
 +|e<​sub>​2</​sub>​(y)|coordinate of e<​sub>​2</​sub>​ along e<​sub>​y</​sub>​|
 +|e<​sub>​2</​sub>​(z)|coordinate of e<​sub>​2</​sub>​ along e<​sub>​z</​sub>​|
 +|Note: These vectors are normalized after reading but should be orthogonal: \\ e<​sub>​1</​sub>​ • e<​sub>​2</​sub>​ = e<​sub>​1</​sub>​(x) * e<​sub>​2</​sub>​(x) + e<​sub>​1</​sub>​(y) * e<​sub>​2</​sub>​(y) + e<​sub>​1</​sub>​(z) * e<​sub>​2</​sub>​(z) = 0||
 +^INITIAL ORIENTATION OF LOCAL AXES (1G10.0) \\ Only if tens of ILOAX = 2 or 4  \\ (only one line if tens of ILOAX = 2, repeated for each element if tens of ILOAX = 4)^^
 +|THETA| Angle between e<​sub>​1</​sub>​ and e<​sub>​x</​sub>​ in degrees|
 +^DEFINITION OF THE ELEMENTS (2I5/​8I5/​6G10)^^
 +|NINTE| Number of integration points (1, 2, 4 or 8) \\ if NINTE = 1, add 40 to MVARI compared to maximum required by laws |
 +|LMATE| Number of the material law|
 +|NODES(8)| List of nodes|
 +|SIG0(6)| List of initial stresses (Only if ISIG0=1)|
elements/blz3d.1551447704.txt.gz · Last modified: 2020/08/25 15:33 (external edit)