CGNS Mid-Level Library - Boundary Conditions

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(General Remarks) (File Operations) (Navigating a CGNS File) (Error Handling) (Structural Nodes) (Descriptors) (Physical Data) (Location and Position) (Auxiliary Data) (Grid Specification) (Solution Data) (Grid Connectivity) (Boundary Conditions) (Equation Specification) (Families) (Time-Dependent Data) (Links)

Boundary Conditions

Boundary Condition Type and Location
- cg_boco_write - Write boundary condition type and data
- cg_boco_normal_write - Write boundary condition normals
- cg_nbocos - Get number of boundary condition in zone
- cg_boco_info - Get boundary condition info
- cg_boco_read - Read boundary condition data and normals
- cg_boco_gridlocation_write - Write boundary condition location
- cg_boco_gridlocation_read - Read boundary condition location
Boundary Condition Datasets
- cg_dataset_write - Write boundary condition dataset info
- cg_dataset_read - Read boundary condition dataset info
- cg_bcdataset_write - Write family boundary condition dataset info
- cg_bcdataset_info - Get number of family boundary condition datasets
- cg_bcdataset_read - Read family boundary condition dataset info
Boundary Condition Data
- cg_bcdata_write - Write boundary condition data
Special Boundary Condition Properties
- cg_bc_wallfunction_write - Write wall function data
- cg_bc_area_write - Write area-related data
- cg_bc_wallfunction_read - Read wall function data
- cg_bc_area_read - Read area-related data

Boundary Condition Type and Location

Node: BC_t (SIDS, File Mapping)

Functions	Modes
`ier = cg_boco_write(int fn, int B, int Z, char boconame, BCType_t bocotype, PointSetType_t ptset_type, cgsize_t npnts, cgsize_t pnts, int *BC);`	`- w m`
`ier = cg_boco_normal_write(int fn, int B, int Z, int BC, int NormalIndex, int NormalListFlag, DataType_t NormalDataType, void NormalList);`	`- w m`
`ier = cg_boco_gridlocation_write(int fn, int B, int Z, int BC, GridLocation_t location);`	`- w m`
`ier = cg_nbocos(int fn, int B, int Z, int *nbocos);`	`r - m`
`ier = cg_boco_info(int fn, int B, int Z, int BC, char boconame, BCType_t bocotype, PointSetType_t ptset_type, cgsize_t npnts, int NormalIndex, cgsize_t NormalListSize, DataType_t NormalDataType, int ndataset);`	`r - m`
`ier = cg_boco_read(int fn, int B, int Z, int BC, cgsize_t pnts, void NormalList);`	`r - m`
`ier = cg_boco_gridlocation_read(int fn, int B, int Z, int BC, GridLocation_t *location);`	`r - m`
`call cg_boco_write_f(fn, B, Z, boconame, bocotype, ptset_type, npnts, pnts, BC, ier)`	`- w m`
`call cg_boco_normal_write_f(fn, B, Z, BC, NormalIndex, NormalListFlag, NormalDataType, NormalList, ier)`	`- w m`
`call cg_boco_gridlocation_write_f(fn, B, Z, BC, location, ier)`	`- w m`
`call cg_nbocos_f(fn, B, Z, nbocos, ier)`	`r - m`
`call cg_boco_info_f(fn, B, Z, BC, boconame, bocotype, ptset_type, npnts, NormalIndex, NormalListSize, NormalDataType, ndataset, ier)`	`r - m`
`call cg_boco_read_f(fn, B, Z, BC, pnts, NormalList, ier)`	`r - m`
`call cg_boco_gridlocation_read_f(fn, B, Z, BC, location, ier)`	`r - m`

Input/Output

	`fn`		CGNS file index number.
	`B`		Base index number, where 1 ≤ `B` ≤ `nbases`.
	`Z`		Zone index number, where 1 ≤ `Z` ≤ `nzones`.
	`BC`		Boundary condition index number, where 1 ≤ `BC` ≤ `nbocos`.
	`nbocos`		Number of boundary conditions in zone `Z`.
	`boconame`		Name of the boundary condition.
	`bocotype`		Type of boundary condition defined. See the eligible types for `BCType_t` in the Typedefs section. Note that if `bocotype` is `FamilySpecified` the boundary condition type is being specified for the family to which the boundary belongs. The boundary condition type for the family may be read and written using `cg_fambc_read` and `cg_fambc_write`.
	`ptset_type`		The extent of the boundary condition may be defined using a range of points or elements using `PointRange`, or using a discrete list of all points or elements at which the boundary condition is applied using `PointList`. When the boundary condition is to be applied anywhere other than points, then `GridLocation_t` under the `BC_t` node must be used to indicate this. The value of `GridLocation_t` may be read or written by `cg_boco_gridlocation_read` and `cg_boco_gridlocation_write`. As in previous versions of the library, this may also be done by first using `cg_goto` to access the `BC_t` node, then using `cg_gridlocation_read` or `cg_gridlocation_write`.
	`npnts`		Number of points or elements defining the boundary condition region. For a `ptset_type` of `PointRange`, `npnts` is always two. For a `ptset_type` of `PointList`, `npnts` is the number of points or elements in the list.
	`pnts`		Array of point or element indices defining the boundary condition region. There should be `npnts` values, each of dimension `IndexDimension` (i.e., 1 for unstructured grids, and 2 or 3 for structured grids with 2-D or 3-D elements, respectively).
	`NormalIndex`		Index vector indicating the computational coordinate direction of the boundary condition patch normal.
	`NormalListFlag`		Flag indicating if the normals are defined in `NormalList` and are to be written out; 1 if they are defined, 0 if they're not.
	`NormalListSize`		If the normals are defined in `NormalList`, `NormalListSize` is the number of points in the patch times `phys_dim`, the number of coordinates required to define a vector in the field. If the normals are not defined in `NormalList`, `NormalListSize` is 0.
	`NormalDataType`		Data type used in the definition of the normals. Admissible data types for the normals are `RealSingle` and `RealDouble`.
	`NormalList`		List of vectors normal to the boundary condition patch pointing into the interior of the zone.
	`ndataset`		Number of boundary condition datasets for the current boundary condition.
	`location`		Grid location used in the definition of the point set. The currently admissible locations are `Vertex` (the default if not given), and `CellCenter`. Interpretation of `CellCenter`, and additional allowable values of grid location depends on the base cell dimension. For `CellDim`=1, `CellCenter` refers to line elements. For `CellDim`=2, `CellCenter` refers to area elements, and the additional value `EdgeCenter` is allowed. For `CellDim`=3, `CellCenter` refers to volume elements, and in addition to `EdgeCenter`, the values of `FaceCenter`, `IFaceCenter`, `JFaceCenter`, and `KFaceCenter` may be used.
	`ier`		Error status.

Notes: (see CPEX 0031)

The use of ElementList and ElementRange for ptset_type is deprecated and should not be used in new code for writing boundary conditions. These are still currently accepted, but will be internally replaced with the appropriate values of PointList/PointRange and GridLocation_t, based on the base cell dimension.
Code which reads older CGNS files, should handle ElementList and ElementRange, however, since many older files contain these specifications for ptset_type.

Boundary Condition Datasets

Node: BCDataSet_t (SIDS, File Mapping)

Functions	Modes
`ier = cg_dataset_write(int fn, int B, int Z, int BC, char DatasetName, BCType_t BCType, int Dset);`	`- w m`
`ier = cg_dataset_read(int fn, int B, int Z, int BC, int Dset, char DatasetName, BCType_t BCType, int DirichletFlag, int NeumannFlag);`	`r - m`
`call cg_dataset_write_f(fn, B, Z, BC, DatasetName, BCType, Dset, ier)`	`- w m`
`call cg_dataset_read_f(fn, B, Z, BC, Dset, DatasetName, BCType, DirichletFlag, NeumannFlag, ier)`	`r - m`

Input/Output

	`fn`		CGNS file index number.
	`B`		Base index number, where 1 ≤ `B` ≤ `nbases`.
	`Z`		Zone index number, where 1 ≤ `Z` ≤ `nzones`.
	`BC`		Boundary condition index number, where 1 ≤ `BC` ≤ `nbocos`.
	`Dset`		Dataset index number, where 1 ≤ `Dset` ≤ `ndataset`.
	`DatasetName`		Name of dataset.
	`BCType`		Simple boundary condition type for the dataset. The supported types are listed in the table of Simple Boundary Condition Types in the SIDS manual, but note that `FamilySpecified` does not apply here.
	`DirichletFlag`		Flag indicating if the dataset contains Dirichlet data.
	`NeumannFlag`		Flag indicating if the dataset contains Neumann data.
	`ier`		Error status.

The above functions are applicable to BCDataSet_t nodes that are children of BC_t nodes.

For BCDataSet_t nodes that are children of a BC_t node, after accessing a particular BCDataSet_t node using cg_goto, the Point Set functions may be used to read or write the locations at which the boundary conditions are to be applied. This is only applicable when the boundary conditions are to be applied at locations different from those used with cg_boco_write to define the boundary condition region (e.g., when the region is being defined by specification of vertices, but the boundary conditions are to be applied at face centers).

When writing point set data to a BCDataSet_t node, in addition to the specification of the indices using cg_ptset_write, the function cg_gridlocation_write must also be used to specify the location of the data with respect to the grid (e.g., Vertex or FaceCenter).

Functions Modes

ier = cg_bcdataset_write(char *DatasetName, BCType_t BCType,       BCDataType_t BCDataType); - w m
ier = cg_bcdataset_info(int *ndataset); r - m
ier = cg_bcdataset_read(int Dset, char *DatasetName, BCType_t *BCType,       int *DirichletFlag, int *NeumannFlag); r - m

call cg_bcdataset_write_f(DatasetName, BCType, BCDataType, ier) - w m
call cg_bcdataset_info_f(ndataset, ier) r - m
call cg_bcdataset_read_f(Dset, DatasetName, BCType, DirichletFlag,      NeumannFlag, ier) r - m

Input/Output

    Dset    Dataset index number, where 1 ≤ Dset ≤ ndataset.
DatasetName Name of dataset.
BCType Simple boundary condition type for the dataset. The supported types are listed in the table of Simple Boundary Condition Types in the SIDS manual, but note that FamilySpecified does not apply here.
BCDataType Type of boundary condition in the dataset (i.e., for a BCData_t child node). Admissible types are Dirichlet and Neumann.
ndataset Number of BCDataSet nodes under the current FamilyBC_t node.
DirichletFlag Flag indicating if the dataset contains Dirichlet data.
NeumannFlag Flag indicating if the dataset contains Neumann data.
ier Error status.

Functions	Modes
`ier = cg_bcdataset_write(char *DatasetName, BCType_t BCType, BCDataType_t BCDataType);`	`- w m`
`ier = cg_bcdataset_info(int *ndataset);`	`r - m`
`ier = cg_bcdataset_read(int Dset, char DatasetName, BCType_t BCType, int DirichletFlag, int NeumannFlag);`	`r - m`
`call cg_bcdataset_write_f(DatasetName, BCType, BCDataType, ier)`	`- w m`
`call cg_bcdataset_info_f(ndataset, ier)`	`r - m`
`call cg_bcdataset_read_f(Dset, DatasetName, BCType, DirichletFlag, NeumannFlag, ier)`	`r - m`

The above functions are applicable to BCDataSet_t nodes that are used to define boundary conditions for a CFD family, and thus are children of a FamilyBC_t node. The FamilyBC_t node must first be accessed using cg_goto.

The first time cg_bcdataset_write is called with a particular DatasetName, BCType, and BCDataType, a new BCDataSet_t node is created, with a child BCData_t node. Subsequent calls with the same DatasetName and BCType may be made to add additional BCData_t nodes, of type BCDataType, to the existing BCDataSet_t node.

Boundary Condition Data

Node: BCData_t (SIDS, File Mapping)

Functions	Modes
`ier = cg_bcdata_write(int fn, int B, int Z, int BC, int Dset, BCDataType_t BCDataType);`	`- w m`
`call cg_bcdata_write_f(fn, B, Z, BC, Dset, BCDataType, ier)`	`- w m`

Input/Output

	`fn`		CGNS file index number.
	`B`		Base index number, where 1 ≤ `B` ≤ `nbases`.
	`Z`		Zone index number, where 1 ≤ `Z` ≤ `nzones`.
	`BC`		Boundary condition index number, where 1 ≤ `BC` ≤ `nbocos`.
	`Dset`		Dataset index number, where 1 ≤ `Dset` ≤ `ndataset`.
	`BCDataType`		Type of boundary condition in the dataset. Admissible boundary condition types are `Dirichlet` and `Neumann`.
	`ier`		Error status.

To write the boundary condition data itself, after creating the BCData_t node using the function cg_bcdata_write, use cg_goto to access the node, then cg_array_write to write the data. Note that when using cg_goto to access a BCData_t node, the node index should be specified as either Dirichlet or Neumann, depending on the type of boundary condition. See the description of cg_goto for details.

Special Boundary Condition Properties

Node: BCProperty_t (SIDS, File Mapping)

Functions	Modes
`ier = cg_bc_wallfunction_write(int fn, int B, int Z, int BC, WallFunctionType_t WallFunctionType);`	`- w m`
`ier = cg_bc_area_write(int fn, int B, int Z, int BC, AreaType_t AreaType, float SurfaceArea, char *RegionName);`	`- w m`
`ier = cg_bc_wallfunction_read(int fn, int B, int Z, int BC, WallFunctionType_t *WallFunctionType);`	`r - m`
`ier = cg_bc_area_read(int fn, int B, int Z, int BC, AreaType_t AreaType, float SurfaceArea, char *RegionName);`	`r - m`
`call cg_bc_wallfunction_write_f(fn, B, Z, BC, WallFunctionType, ier)`	`- w m`
`call cg_bc_area_write_f(fn, B, Z, BC, AreaType, SurfaceArea, RegionName, ier)`	`- w m`
`call cg_bc_wallfunction_read_f(fn, B, Z, BC, WallFunctionType, ier)`	`r - m`
`call cg_bc_area_read_f(fn, B, Z, BC, AreaType, SurfaceArea, RegionName, ier)`	`r - m`

Input/Output

	`fn`		CGNS file index number.
	`B`		Base index number, where 1 ≤ `B` ≤ `nbases`.
	`Z`		Zone index number, where 1 ≤ `Z` ≤ `nzones`.
	`BC`		Boundary condition index number, where 1 ≤ `BC` ≤ `nbocos`.
	`WallFunctionType`		The wall function type. Valid types are `CG_Null`, `CG_UserDefined`, and `Generic`.
	`AreaType`		The type of area. Valid types are `CG_Null`, `CG_UserDefined`, `BleedArea`, and `CaptureArea`.
	`SurfaceArea`		The size of the area. (In Fortran, this is a Real*4 value.)
	`RegionName`		The name of the region, 32 characters max.
	`ier`		Error status.

The "write" functions will create the BCProperty_t node if it doesn't already exist, then add the appropriate boundary condition property. Multiple boundary condition properties may be recorded under the same BCProperty_t node.

The "read" functions will return with ier = 2 = CG_NODE_NOT_FOUND if the requested boundary condition property, or the BCProperty_t node itself, doesn't exist.