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You are here: metafor.ltas.ulg.ac.be » doc » Documentation » elements » General Points » Volume element
Trace: • Marco Lucio CERQUAGLIA • Backward extrusion • Saving history curves to disk • Yield Stress • Volume element
doc:user:elements:volumes:volumeelement

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doc:user:elements:volumes:volumeelement [2015/10/13 22:32] – wauteletdoc:user:elements:volumes:volumeelement [2025/04/23 12:05] (current) – radermecker
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 ===== Introduction ===== ===== Introduction =====
  
-In this section, Metafor volume element are described. To them is associated a ''[[doc:user:elements:volumes:volumeinteraction|FieldApplicator]]'' interaction.+In this section, Metafor volume element are described. A ''[[doc:user:elements:volumes:volumeinteraction|FieldApplicator]]'' interaction is associated to them.
  
 ===== Volume[2|3]DElement ===== ===== Volume[2|3]DElement =====
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 === Description === === Description ===
  
-''Volume2DElement'' and ''Volume3DElement'' are basic elements in Metafor. ''Volume2DElement'' is a quadrangle with 4 nodes in 2D, when ''Volume3DElement''is a hexaedron with 8 nodes in 3D. Each element has respectively 8 and 24 degrees of freedom.+''Volume2DElement'' and ''Volume3DElement'' are basic elements in Metafor. ''Volume2DElement'' is a quadrangle with 4 nodes in 2D, while ''Volume3DElement'' is a hexaedron with 8 nodes in 3D. Each element has respectively 8 and 24 degrees of freedom.
  
 By default, if $n$ is the degree of mechanical interpolation and $d$ the element dimension, the number of integration points in the deviatoric part of the stress field is $(n+1)^{d}$, unless stated otherwise with the definition of ''NIPDKSI'', ''NIPDETA'' or ''NIPDZETA'' (see [[#Parameters ]]). \\ For example, the interpolation of ''Volume2DElement'' is of the first degree ($n=1$), and it is a 2D element ($d=2$), leading to 4 integration points. By default, if $n$ is the degree of mechanical interpolation and $d$ the element dimension, the number of integration points in the deviatoric part of the stress field is $(n+1)^{d}$, unless stated otherwise with the definition of ''NIPDKSI'', ''NIPDETA'' or ''NIPDZETA'' (see [[#Parameters ]]). \\ For example, the interpolation of ''Volume2DElement'' is of the first degree ($n=1$), and it is a 2D element ($d=2$), leading to 4 integration points.
  
-The number of integration points in the volume part of the stress field (pressure) depends on the chosen [[doc:user:elements:volumes:elements_formulation|method to integrate stresses]] are cannot be modified.+The number of integration points in the volume part of the stress field (pressure) depend on the chosen [[doc:user:elements:volumes:elements_formulation|method to integrate stresses]] and cannot be modified.
  
 === Remarks === === Remarks ===
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 ===== QuadVolume[2|3]DElement ===== ===== QuadVolume[2|3]DElement =====
  
-''QuadVolume2DElement'' and ''QuadVolume3DElement'' are quadratic elements. ''QuadVolume2DElement'' is a 8-nodes quadratic quadrangle, ''QuadVolume2DElement'' a 20 quadratic hexaedron. They are purely mechanical, with respectively 16 and 60 dofs.+''QuadVolume2DElement'' and ''QuadVolume3DElement'' are quadratic elements. ''QuadVolume2DElement'' is a 8-nodes quadratic quadrangle, ''QuadVolume3DElement'' a 20 quadratic hexaedron. They are purely mechanical, with respectively 16 and 60 dofs.
  
 By default, stresses are integrate over 4/27 integration points in the deviatoric part in 2/3D, with the formula already stated for ''Volume[2|3]DElement''. The standard formulation must be used (''CAUCHYMECHVOLINTMETH = VES_CMVIM_STD''), which is not the default one. By default, stresses are integrate over 4/27 integration points in the deviatoric part in 2/3D, with the formula already stated for ''Volume[2|3]DElement''. The standard formulation must be used (''CAUCHYMECHVOLINTMETH = VES_CMVIM_STD''), which is not the default one.
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 Quadratic, 6-nodes triangular element in 2D, 12 dofs. The standard formulation must be used (''CAUCHYMECHVOLINTMETH = VES_CMVIM_STD''). Quadratic, 6-nodes triangular element in 2D, 12 dofs. The standard formulation must be used (''CAUCHYMECHVOLINTMETH = VES_CMVIM_STD'').
  
-By default, stresses are integrate over 3 integration points in the deviatoric part.+By default, stresses are integrated over 3 integration points in the deviatoric part.
  
 __Remark__: To use these higher order elements, the mesh must be also defined as second or third degree.  __Remark__: To use these higher order elements, the mesh must be also defined as second or third degree. 
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 Quadratic, 10-nodes tetrahedron in 3D, 30 dofs. As with quadratic elements in 2D, the standard formulation must be used (''CAUCHYMECHVOLINTMETH = VES_CMVIM_STD''). Quadratic, 10-nodes tetrahedron in 3D, 30 dofs. As with quadratic elements in 2D, the standard formulation must be used (''CAUCHYMECHVOLINTMETH = VES_CMVIM_STD'').
  
-By default, stresses are integrate over 4 integration points in the deviatoric part.+By default, stresses are integrated over 4 integration points in the deviatoric part.
  
 __Remark__: To use these higher order elements, the mesh must be also defined as second or third degree.  __Remark__: To use these higher order elements, the mesh must be also defined as second or third degree. 
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 ^      Code Metafor        ^          Description                                      ^  Dependency  ^ ^      Code Metafor        ^          Description                                      ^  Dependency  ^
 | ''MATERIAL''             | Number of the volume material to consider   |      -    | | ''MATERIAL''             | Number of the volume material to consider   |      -    |
-| ''STIFFMETHOD''          | Method used to compute the stiffness matrix \\ = ''STIFF_ANALYTIC'' : analytic matrix (default) \\ = ''STIFF_NUMERIC''  : numerical matrix                    |     -       |                      +| ''STIFFMETHOD''          | Method used to compute the stiffness matrix \\ = ''STIFF_ANALYTIC'' : analytic matrix (default) \\ = ''STIFF_NUMERIC''  : numerical matrix                    |     -       |     
 +| ''DAMPSTIFF''            | Part of the Stiffness matrix used to build damping matrix used by [[doc:user:integration:scheme:dynimpl#damped_alpha-generalized_family|Damped Time Integration scheme]] \\ usual value : 1.0e-7 - 1.0e-5  |     Time (need DMUPERSTEP or DMUPERSTAGE)      | 
 +| ''DAMPMASS''             | Part of the Mass matrix used tobuild damping matrix used by [[doc:user:integration:scheme:dynimpl#damped_alpha-generalized_family|Damped Time Integration scheme]] \\ usual value : 1.0e3 - 1.0e5    |     Time  (need DMUPERSTEP or DMUPERSTAGE)     |
 | ''OMEGA''                | Angular speed (°/s) to simulate a rotating frame (calculation of centrifugal and Coriolis forces). \\ If ''MDE_IQSI=1'' and ''MDE_NDYN=2'', centrifugal forces are computed during a quasi-static equilibrium phase. Then, they are replaced by the real structural rotation. \\ If ''MDE_IQSI=2'' and ''MDE_NDYN=2'', centrifugal forces are computed during a quasi-static equilibrium phase. Then, the simulation is carried in the moving frame, so centrifugal and Coriolis forces are taken into account in the model.  |  time | | ''OMEGA''                | Angular speed (°/s) to simulate a rotating frame (calculation of centrifugal and Coriolis forces). \\ If ''MDE_IQSI=1'' and ''MDE_NDYN=2'', centrifugal forces are computed during a quasi-static equilibrium phase. Then, they are replaced by the real structural rotation. \\ If ''MDE_IQSI=2'' and ''MDE_NDYN=2'', centrifugal forces are computed during a quasi-static equilibrium phase. Then, the simulation is carried in the moving frame, so centrifugal and Coriolis forces are taken into account in the model.  |  time |
 | ''OMEGA_PT1''            | Number of the first point which defines the rotation axis      |          -           | | ''OMEGA_PT1''            | Number of the first point which defines the rotation axis      |          -           |
 | ''OMEGA_PT2''            | Number of the second point which defines the rotation axis    |          -           | | ''OMEGA_PT2''            | Number of the second point which defines the rotation axis    |          -           |
 | ''CORIOLIS''             | Boolean to take into account Coriolis forces in a moving frame, during a dynamic simulation.\\ True (default) / False   |   -   | | ''CORIOLIS''             | Boolean to take into account Coriolis forces in a moving frame, during a dynamic simulation.\\ True (default) / False   |   -   |
-| ''GRAVITY_X'', ''GRAVITY_Y'', ''GRAVITY_Z''  | Gravity       |        time |+| ''GRAVITY_X'', ''GRAVITY_Y'', ''GRAVITY_Z''  | Gravity       |        time   |
 | ''CAUCHYMECHVOLINTMETH'' | [[doc:user:elements:volumes:elements_formulation|Method]] used to integrate the mechanical part of volume elements (stresses) \\ = ''[[doc:user:elements:volumes:elements_formulation#formulation_standard|VES_CMVIM_SRI]]'' \\ = ''[[doc:user:elements:volumes:elements_formulation#sous_integration_selective_avec_report_de_pression|VES_CMVIM_SRIPR]]'' (default) \\ = ''[[doc:user:elements:volumes:elements_formulation#formulation_standard|VES_CMVIM_STD]]'' \\ = ''[[doc:user:elements:volumes:elements_formulation#formulation_eas|VES_CMVIM_EAS]]'' |  -  | | ''CAUCHYMECHVOLINTMETH'' | [[doc:user:elements:volumes:elements_formulation|Method]] used to integrate the mechanical part of volume elements (stresses) \\ = ''[[doc:user:elements:volumes:elements_formulation#formulation_standard|VES_CMVIM_SRI]]'' \\ = ''[[doc:user:elements:volumes:elements_formulation#sous_integration_selective_avec_report_de_pression|VES_CMVIM_SRIPR]]'' (default) \\ = ''[[doc:user:elements:volumes:elements_formulation#formulation_standard|VES_CMVIM_STD]]'' \\ = ''[[doc:user:elements:volumes:elements_formulation#formulation_eas|VES_CMVIM_EAS]]'' |  -  |
 | ''CONSERVINGMETHOD''     | Use of ''[[doc:user:integration:scheme:dynimpl#conservative algorithm]]'' \\ = ''VES_WITHOUTCORRECTION'' : plastic correction tensors neglected (default) \\ = ''VES_WITHCORRECTION'' : plastic correction tensors considered |  -  | | ''CONSERVINGMETHOD''     | Use of ''[[doc:user:integration:scheme:dynimpl#conservative algorithm]]'' \\ = ''VES_WITHOUTCORRECTION'' : plastic correction tensors neglected (default) \\ = ''VES_WITHCORRECTION'' : plastic correction tensors considered |  -  |
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 | ''TEAS'' | Transformation of [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] modes from the isoparametric space \\  =0 : Simo-Armero transformation (default) \\ =1 : Glaser-Armero transformation [do not use, still under development] |  -  | | ''TEAS'' | Transformation of [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] modes from the isoparametric space \\  =0 : Simo-Armero transformation (default) \\ =1 : Glaser-Armero transformation [do not use, still under development] |  -  |
 | ''EEAS'' | Extrapolation of [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] modes \\ =0 : modes set to 0 for each time step (safe but slow). \\ =1 : classical extrapolation (default) \\ =2 : initialization to the value corresponding to the previous step. \\ =3 : set to 0 for each iteration |  -  | | ''EEAS'' | Extrapolation of [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] modes \\ =0 : modes set to 0 for each time step (safe but slow). \\ =1 : classical extrapolation (default) \\ =2 : initialization to the value corresponding to the previous step. \\ =3 : set to 0 for each iteration |  -  |
-| ''PEAS'' | Accuracy of resolution of [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] modes (default: 1.0e-8)|  -  |+| ''PEAS'' | Accuracy of resolution of [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] modes (default: 1.0e-8) unfortunately NOT adimensional!!! \\ => = 1.0e-8 for "small tests" in mm \\ => = 1.0e-6 for "real tests" in mm \\ => = 1.0e-9 for "real tests" in m |  -  |
 | ''VERBOSE'' | (bool) Debug information concerning resolution of  [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] (default: false)|  -  | | ''VERBOSE'' | (bool) Debug information concerning resolution of  [[doc:user:elements:volumes:elements_formulation#formulation_eas|EAS]] (default: false)|  -  |
 +
doc/user/elements/volumes/volumeelement.1444768374.txt.gz · Last modified: (external edit)
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