AVS Modules read_F3D copyright 1992,1993,1994 Michael J. Rangitsch 8 June 1994 NAME read_F3D - read in a FLOW3D data file from Harwell FLOW3D version 3 (multiblock flow solver code) SUMMARY Name read_F3D Type data Inputs none Outputs ucd (data at cells), geometry Parameters NAME TYPE Read F3D Browser file browser show blocks boolean DESCRIPTION This module reads either a formatted or unformatted multiblock FLOW3D solution file (from Harwell FLOW3D version 3) and stores the cfd data as a ucd data set. The dummy nodes stored at the edges of each computational block are removed by the module. The n-vector data at each computational cell is stored as cell data, to use most of the ucd modules, this must be converted to nodal data. The cells of the ucd structure are all hexahedra. Possible orientation (handedness) changes in the grid can defeat the interblock boundaries removal. To fix this, use the AVS 5.0 module 'ucd reverse cell' to correct the topology. This module ensures that all cells have the same vertex ordering. Version 1.1 of read_F3D sets the minimum and maximum of the cell data values. This is is required for some of the other ucd routines to work correctly. Version 2.0.1 of read_F3D modifies the treatment of data labels and adds units to the 'default' variables (u,v and w velocities, pressure, volume fraction, k and epsilon (if stored)). The cell indexing is improved (through a macro) and code is added to remove the internal block boundaries (this is the default.) Removal of the block boundaries gets rid of discontinuous isosurfaces that existed in the earlier versions Version 2.1 of read_F3D corrects all of the block boundary removals. Each removal 'switch' has been tested at least once, and all are apparently correct. Version 3.0 of read_F3D adds a geometry output which displays all of the 2 dimensional patches in the FLOW3D data set as objects named the way the patches are named (all names converted to lower case). The inter-block boundary patches are not shown. This code probably doesn't work for 3 dimensional patches. The geometries are under a single parent which allows easier manipulation of the properties (like transparencies). Version 3.1 of read_F3D corrects a minor problem in the glue patch removal when 5 blocks meet. Version 4.0 of read_F3D improves the handling of the data groups by not requiring them in any particular order. This apparently fixes the problem of not handling single block data sets. The code also correctly handles cylindrical coordinates. Version 5.0 of read_F3D adds coding to read an unformatted data file as well as a formatted one. The difference is detected by the code in the initial file header. Unformatted reads are much faster than formatted reads. File space requirements are also much lower. The module works correctly on both a DEC ALPHA OSF machine and a DEC Ultrix machine. COMMENTS/QUESTIONS/SUGGESTIONS please send them to me at mrangitsch@dow.com INPUT none OUTPUT The output is a ucd data set with data stored at the cells and a geometry representing the structures given by the 2 dimensional patches PARAMETERS Read F3D Browser - a file browser to choose the FLOW3D dump file, generally (xxx.dmp). show blocks - a boolean parameter to show the block structure (by not removing the interblock patches). Showing the blocks can result in discontinuous isosurfaces and 'kinks' in streamlines. EXAMPLE The following network shows a typical usage of read_F3D: read_F3D ___________________| | | | | ucd cell to node generate colormap | | | | ucd reverse cell | | | | | -----ucd extract scalars | | | | | | | | |-------------| | | ucd contour | | | | | |-----------| | ucd to geom | | ---------| | geometry viewer RELATED MODULES read ucd, write ucd, read_flow3d AVS Module read_F3D Michael J. Rangitsch 8 June 1994