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doc:user:elements:shells:boundary

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doc:user:elements:shells:boundary [2013/07/10 14:18] – created jorisdoc:user:elements:shells:boundary [2016/03/30 15:23] (current) – external edit 127.0.0.1
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 +====== DG shell boundary conditions ======
  
 +Since shell formalism only takes displacements into account, rotating boundary conditions are imposed though a DG formulation.
 +
 +===== Materials =====
 +
 +As for [[doc:user:start#boundary condition elements]], there is no material to associate to an element.
 +
 +===== Elements =====
 +
 +Since no material is required, the first stage consists in defining an ElementProperties:
 +
 +  prp = ElementProperties(typeEl)
 +  prp.put(param1, value1)
 +  prp.depend(param1, fct1, Lock1)) #facultatif
 +  ...
 +
 +where
 +
 +|''typeEl'' | desired type of element (for example ''BoundaryDgShellFirstDegreeElement'')|
 +|''param1''| name of the property associated to the element (for example ''STIFFMETHOD'')|
 +|''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) |
 +
 +====  BoundaryDgShellFirstDegreeElement ====
 +
 +DG interface element to insert on shell boundaries to provide BCs. 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]].
 +
 +====  BoundaryDgShellSecondDegreeElement ====
 +
 +Same as ''BoundaryDgShellFirstDegreeElement'', but 8-nodes second order shell element.
 +
 +====  BoundaryDgShellNineNodeSecondDegreeElement ====
 +
 +Same as ''BoundaryDgShellSecondDegreeElement'', but 9-nodes second order shell element.
 +
 +====  BoundaryDgShellSixteenNodeThirdDegreeElement ====
 +
 +Same as ''BoundaryDgShellNineNodeSecondDegreeElement'', but 16-nodes third order shell element.
 +
 +==== Parameters of shell boundary conditions 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)|  -  |
 +| ''NORMAL_PT1''| First point governing the element of the shell normal |  -  | 
 +| ''NORMAL_PT2''| First point governing the element of the shell normal |  -  |
 +
 +
 +===== Interactions =====
 +
 +Once created, the element is generated by a ''DgShellInteraction'':
 +
 +  dgBound = DgShellInteraction(number)
 +  dgBound.push(gObject1)
 +  dgBound.push(gObject2)
 +  ...
 +  dgBound.addProperty(prp)
 +  interactionset.add(dgBound)  # the interaction is added in InteractionSet
 +
 +or 
 +
 +  dgBound = interactionset.add( DgShellInteraction(number) )
 +  dgBound.push(gObject1)
 +  dgBound.push(gObject2)
 +  ...
 +  dgBound.addProperty(prp)
 +
 +| ''number'' | Number of the material to consider |
 +| ''gObject1'', ''gObject2'' | mesh geometric entities |
 +| ''prp'' | [[doc:user:elements:general:def_element_properties|Properties]] of the [[#Eléments|DG boundary condition elements]] to generate |
 +
 +Generally, entities are lines or groups of nodes on a line.

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