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doc:user:elements:shells:interface

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doc:user:elements:shells:interface [2013/07/10 15:15] jorisdoc:user:elements:shells:interface [2016/03/30 15:23] (current) – external edit 127.0.0.1
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 +====== DG shell interactions ======
  
 +Once [[doc:user:elements:shells:shell|shell interactions]] are defined, they must be completed with (Discontinuous Galerkin) interface interactions, following the well-known material-element-interaction pattern.
 + 
 +
 +===== Materials =====
 +
 +First, the material is defined as:
 +
 +  materialno = materialset.define (number, type)
 +  materialno = materialset(number)
 +  materialno.put(param, value)
 +  materialno.depend(param, fct, Key(Lock)))
 +  ...
 +
 +|''number'' | material number (must be unique with respect to all elements in ''materialset'', not to shells)  |
 +|''type'' | shell type (for example ''DgShellMaterial'') |
 +|''param'' | name of the shell parameter (for example ''STABILIZATION_PARAMETER'') |
 +|''value'' | value of the corresponding parameter ''param''|
 +|''fct'' | function which characterizes the dependency of the property (optional: no fct if no dependency) |
 +|''Lock'' | [[doc:user:general:locks|Lock]] which defines the dependency variable of the property (compulsory if there is a dependency) |
 +
 +====  DgShellMaterial ====
 +
 +=== Description ===
 +
 +DG law for shell interface elements.
 +
 +==== Parameters ====
 +^   Name            ^     Metafor Code      Dependency ^
 +| Stabilization parameter (>1)                     ''STABILIZATION_PARAMETER''    |              |
 +
 +===== Elements =====
 +
 +After defining the [[#Materials|material]], it must be associated to an ''[[doc:user:elements:general:def_element_properties|ElementProperties]]'':
 +
 +  prp = ElementProperties(typeEl)
 +  prp.put(param1, value1)
 +  prp.depend(param1, fct1, Lock1)) #facultatif
 +  ...
 +
 +where
 +
 +|''type'' | desired type of element (for example ''DgShellFirstDegreeElement'') |
 +|''param1''| name of the property associated to the element (for example ''MATERIAL'' to associate the desired material)|
 +|''value1''| value of the corresponding property |
 +|''fct1''| function which characterizes the dependency of the property (optional: no fct if no dependency) |
 +|''Lock1''| [[doc:user:general:locks|Lock]] which defines the dependency variable of the property (compulsory if there is a dependency) |
 +
 +====  DgShellFirstDegreeElement ====
 +
 +DG interface element to insert between shells. These are 2-nodes linear lines, but they are interfering over all neighboring dofs. 
 +
 +By default, stresses are integrated over ''dim*2'' integration points. The material used is  [[doc:user:elements:shells:interface#dgShellMaterial]].
 +
 +
 +
 +====  DgShellSecondDegreeElement ====
 +
 +Same as ''DgShellFirstDegreeElement'', but 8-nodes second order shell element.
 +
 +
 +====  DgShellNineNodeSecondDegreeElement ====
 +
 +Same as ''DgShellSecondDegreeElement'', but 9-nodes second order shell element.
 +
 +====  DgShellSixteenNodeThirdDegreeElement ====
 +
 +Same as ''DgShellNineNodeSecondDegreeElement'', but 16-nodes third order shell element.
 +
 +
 +==== Parameters of shell DG interface elements ====
 +^   Name            ^     Metafor Code      Dependency ^
 +| ''MATERIAL''    | Number of the material to consider              |  -  |
 +| ''STIFFMETHOD'' | Method used to compute the stiffness matrix \\ = ''STIFF_ANALYTIC'' : analytic matrix (default) \\ = ''STIFF_NUMERIC''  : numerical matrix            |  -  |
 +| ''BENDING_NPG''  | Number of integration points along one direction for bending solving \\ = 2 classical solving  (second order)\\ = 3 EAS solving with 22 or 7 added modes (8 or 9-nodes second order)\\ = 4 solving without EAS (16-nodes third order)  |  -  |
 +
 +
 +===== Interactions =====
 +
 +[[doc:user:elements:shells:interface#Eléments|DG shell interface elements]] are generated at the start of the simulation by a ''DgShellInteraction'' [[doc:user:general:glossaire#Interaction]], defined over desired entities. 
 +
 +  dg = DgShellInteraction(number)
 +  dg.push(gObject1)
 +  dg.push(gObject2)
 +  ...
 +  dg.addProperty(prp)
 +  interactionset.add(dg)                 # the interaction is added in InteractionSet 
 +
 +or
 +
 +  dg = interactionset.add( DgShellInteraction(number) )
 +  dg.push(gObject1)
 +  dg.push(gObject2)
 +  ...
 +  dg.addProperty(prp)
 +
 +
 +| ''number'' | User number of the interaction|
 +| ''gObject1'', ''gObject2'' | mesh geometric entities where the finite elements are applied |
 +| ''prp'' | [[doc:user:elements:general:def_element_properties|Properties]] of[[doc:user:elements:shells:interface#Elements|DG interface elements]] to generate |
 +
 +Careful, for now if two entities have common nodes, to many elements will be generated. 

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