4.2.4 Boundary Initialization

A general solver must be able to define boundaries and corresponding conditions. To refer to a special boundary a structure similar to the grid section has to be defined:

Boundary = <boundary name>
{
   <interface definition>   # refer to a special interface/boundary
   <model definition>       # initialize boundary with analytical model
}

where Boundary is a keyword and <boundary name> is a valid name defined in the source file. For the case that no boundaries are defined in the source file because a previous simulation step had no need of boundary definitions, a boundary extraction mechanism (Section 4.4.2) has been implemented that can be used to estimate the available boundaries and interfaces. The including subfields of the boundary section are:

• The <interface definition> is a means to refer to a definite boundary

  interface(<gridname>,Top|Bottom|Left|Right|Front|Back)
  

  or an interface between two grids:

  interface(<gridname1>,<gridname2>)
  

• The boundary model can be defined in the same manner as in the model definition described in the previous section. The only difference is that the quantity names have to be equal to the used volume model names. This is necessary to tell the simulation system which quantities have to be influenced or connected via a boundary model:

  Model = <modelname>(<Q1>,<Q2>, ... , <Qn>) 
  {
     Value(<quantity name>) = <const>
     Value(<quantity name>) = Analytical <function>
     Value(<quantity name>) = Read <attribute>
     Value(<quantity name>) = Read(<physical>,<logical>) <attribute>
  }