IC3 V4 Format

Only for finite-volume computation.

The IC3 restart files use the HDF5 file format to manage, process, and store the restart data. The data format is proprietary.

The mesh file is separated from the solution files when the mesh is not deformable.

HDF5 can store two primary types of objects: datasets and groups. A dataset is essentially a multidimensional array of data elements, and a group is a structure for organizing objects in an HDF5 file. The format supports user-defined attributes that can be used to add descriptive metadata to the file as a whole or any component data object.

IC3 group names start with a capital letter and have a capital letter for each new word, with no underscores except for groups related to specific labels.

IC3 dataset names are all lowercase.

Mesh File Organization

The mesh filename should be <mesh>.h5.

File Attributes

ic3_format_version	64-bit integer	optional
hdf5_version	string	optional
cfdtools_version	string	optional
meshtype	string	optional
cv_count	64-bit integer	required
fa_count	64-bit integer	required
no_count	64-bit integer	required

File Objects

coordinates	HDF5 Dataset	required
Connectivities	HDF5 Group	required
Boundaries	HDF5 Group	required
NodeData	HDF5 Group	optional

Dataset coordinates

Point coordinates of the mesh.

Data type: 64-bit floating-point

Attributes: | | | | |---|---|---| | system | string | optional in ["cartesian", "cylindrical"] |

Group Connectivities

Face	HDF5 Group	required
Cell	HDF5 Group	optional

The Face group stores the datasets for face-based connectivity.

noofa_v	32-bit integer	required	NGON_n (UGP_IO_NOOFA_I_AND_V, conn->noofa_v)
noofa_i	32-bit integer	required	ElementStartOffset(NGON_n) (kind of UGP_IO_NOOFA_I_AND_V, kind of conn->noofa_i)
cvofa	32-bit integer	required	ParentElements (NGON_n) (UGP_IO_CVOFA, conn->cvofa)

The Cell group stores the datasets for element-based connectivity.

hexa8	64-bit integer	optional	(element-nodes connectivity)

Group Boundaries

kinds	HDF5 Dataset, 32-bit integer	required
labels	HDF5 Dataset, string	required
offsets	HDF5 Dataset, 32-bit integer	required

The kinds dataset stores the IC3 type of boundaries.

The offsets dataset stores the offset to reach the first face of the boundary in the global list of faces.

The labels dataset stores the name of the boundaries.

For each boundary name in the labels array, a HDF5 group with the exact same name may be present in the Boundaries group. If so, it contains a dataset to give the periodic transformation.

< boundary name >	HDF5 Dataset, 64-bit floating-point	required

Group NodeData

node_gb_index	HDF5 Dataset, 64-bit integer	optional

Solution File Organization

The solution filename should be <restart>.<iteration>.h5.

A solution file stores data that corresponds to a single physical time. The name should contain the iteration number of the computation corresponding to this time.

File Attributes

step	64-bit integer	required
time	64-bit floating-point	required

The step attribute is the number of iterations already performed during previous runs.

The time attribute is the physical time of the stored data.

File Objects

rho	HDF5 Dataset	required
rhoe	HDF5 Dataset	required
rhou	HDF5 Dataset	required
VolumeStats	HDF5 Group	required

Datasets rho, rhoe, rhou

Conservative variables located at the control volume centers.

Data type: 64-bit floating-point

Group VolumeStats

Thos group stores the time-averaged variables.

< variable >_avg	HDF5 Dataset, 64-bit floating-point	optional
< variable >_rms	HDF5 Dataset, 64-bit floating-point	optional
< variable >_rey	HDF5 Dataset, 64-bit floating-point	optional

Attributes: | | | | |---|---|---| | < variable >_wgt | 64-bit floating-point | optional/required |

If a variable exists, then the attribute is required.