AFLR4 Overview
AFLR4 is an unstructured 3D surface mesh generation code. It uses the Advancing-Front/Local-Reconnection (AFLR) procedure to generate a 3D surface mesh on multiple surfaces, each with either a CAD geometry component definition, a discrete geometry component definition, or a composite definition. Distribution of the surface point spacing (length scale) is determined from an automated surface curvature driven process with proximity checking and localized spacing reduction. AFLR4 includes a full integration of functions for EGADS with Open CASCADE CAD.
The following is a simple summary of usage with options. For more information, see Usage Summary for a summary of options and default values and Option Details for a detailed description of all options.
aflr4 [input_arg_file_name] [aflr4_param_options]
PARAMETER NAME DESCRIPTION
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PROGRAM CONTROL & I/O PARAMETERS
-File_Status_Monitor : Turn on file status monitor.
-Memory_Monitor : Turn on memory monitor.
-Memory_Monitor2 : Turn on memory monitor.
-build : List program version build number.
-h : List summary of input parameters.
-h_all : List summary of all input parameters.
-h_io : List summary of file I/O parameters.
-help : List documentation of input parameters.
-help_all : List documentation of all input parameters.
-help_io : List documentation of file I/O parameters.
-out : Generate an output file.
-log : Generate an output file.
-out_a : Append an output file.
-log_a : Append an output file.
-outf : Send output to a file only.
-logf : Send output to a file only.
-outf_a : Append output to a file only.
-logf_a : Append output to a file only.
-ver : List program version number.
-version : List program version information.
Help_Flag : List documentation of input parameters.
Help_UG_IO_Flag : List documentation of file I/O parameters.
Output_File_Flag : Output file flag.
-v : Use executable in specified directory.
Arg_File_Name : Input argument file name.
-arg : Input argument file name.
Input_File_Name : Input CAD file case name or file name or input CAD file name.
-i -cad -igrid -case : Input CAD file case name or file name or input CAD file name.
Output_Grid_File_Name : Output grid file name or suffix.
-o -ogrid : Output grid file name or suffix.
TMP_File_Dir : Temporary file directory.
-tmp : Temporary file directory.
FLAG PARAMETERS (OFTEN USED)
-er_all : Use global edge mesh spacing refinement.
-np : Run in parallel processing mode using np processes.
-quad : Generate a mixed quad/tria-face grid.
OPTION PARAMETERS (OFTEN USED)
BL_IDs : List of IDs for BL Generating Solid surfaces.
-bl_ids : List of IDs for BL Generating Solid surfaces.
BL_Int_IDs : List of IDs for BL Intersecting surfaces.
-bl_ints -bl_int_ids -ints -int_ids : List of IDs for BL Intersecting surfaces.
FF_IDs : List of IDs to for FarField surfaces.
-ffs -ff_ids : List of IDs to for FarField surfaces.
Std_IDs : List of IDs to for Solid surfaces.
-stds -std_ids : List of IDs to for Solid surfaces.
Trnsp_BL_IDs : List of IDs for BL Generating Transparent surfaces.
-trnsp_bl_ids : List of IDs for BL Generating Transparent surfaces.
Trnsp_BL_Int_IDs : List of IDs for BL Intersecting Transparent surfaces.
-trnsp_bl_int_ids : List of IDs for BL Intersecting Transparent surfaces.
Trnsp_IDs : List of IDs for Transparent surfaces.
-trnsp_ids : List of IDs for Transparent surfaces.
Trnsp_Intl_BL_IDs : List of IDs for BL Generating Internal Transparent surfaces.
-trnsp_intl_bl_ids : List of IDs for BL Generating Internal Transparent surfaces.
Trnsp_Intl_IDs : List of IDs for Internal Transparent surfaces.
-trnsp_intl_ids : List of IDs for Internal Transparent surfaces.
Trnsp_Src_IDs : List of IDs for Transparent Source surfaces.
-trnsp_src_ids : List of IDs for Transparent Source surfaces.
auto_set_ff_bc : Automatic farfield grid BC flag.
mer_all : Global edge mesh spacing refinement weight flag.
nproc : Number of processes to use.
parallel_mode : Parallel processing mode flag.
NUMERIC PARAMETERS (OFTEN USED)
curv_angle : Curvature spacing angle in degrees.
ref_len : Reference length for components/bodies.
FLAG PARAMETERS (SOMETIMES USED)
-add_ff : Add a box-shaped farfield definition to configuration.
-add_ff2 : Add a rectangular-box-shaped farfield definition to configuration.
-ext : Use external sizing routine.
-met2 : Use metric space with advancing-front point placement.
-met3 : Use metric space with advancing-point point placement.
OPTION PARAMETERS (SOMETIMES USED)
BC_IDs : List of IDs to set grid BC parameters.
bc_ids : List of IDs to set grid BC parameters.
Grid_BC_Flag : List of grid BC flags to set.
bc_list : List of grid BC flags to set.
add_ff_geom : Farfield add-on flag.
cad_param_reset : CAD parameter reset flag.
cmp_ids : List of surface IDs to set as components.
cmp_list : List of component identifiers for each component/body specified.
erw_ids : List of surface IDs to set edge mesh spacing refinement weight.
esf_ids : List of edge IDs to set edge mesh spacing scale factor.
malign : Metric alignment flag.
merge_ids : List of discrete geometry definition surface IDs to to merge.
merge_sets : List of the number of IDs for each merge set.
min_ncell : Minimum number of cells between two components/bodies.
sf_ids : List of surface IDs to set surface mesh spacing scale factor.
NUMERIC PARAMETERS (SOMETIMES USED)
BL_thickness : Boundary layer thickness for proximity checking.
-bl_del : Boundary layer thickness for proximity checking.
Re_l : Reynolds Number for estimating BL thickness,
-Re : Reynolds Number for estimating BL thickness,
erw_all : Global edge mesh spacing refinement weight.
erw_list : List of edge mesh spacing refinement weights.
esf_list : List of edge mesh spacing scale factors.
ff_cdfr : Farfield growth rate for field point spacing.
ff_size : Farfield size factor.
max_scale : Relative maximum spacing.
rel_max_sp : Relative maximum spacing.
sf_global : Global surface mesh spacing scale factor.
sf_all : Global surface mesh spacing scale factor.
sf_list : List of surface mesh spacing scale factors.
FLAG PARAMETERS (SELDOM USED)
-no_prox : Disable proximity checking.
OPTION PARAMETERS (SELDOM USED)
Rec_IDs : List of IDs to reset Reconnection flag.
-rec_ids : List of IDs to reset Reconnection flag.
auto_mode : Auto-spacing mode flag.
create_tess : Output CAD tess data creation flag,
geom_mmsg : Geometry definition output flag,
mier4 : Isolated edge refinement flag.
mier_ids : List of surface IDs to set isolated edge refinement flag.
mier_list : List of isolated edge refinement flags.
mw_cad_def : CAD definition file write flag,
quad_ids : List of surface IDs for quad-face combination.
surf_gen_mmsg : Surface mesh generation output flag,
NUMERIC PARAMETERS (SELDOM USED)
er_lim : Edge mesh spacing refinement limit.
FLAG PARAMETERS (RARELY USED)
-grow : Use specified growth in element size.
-grow1 : Use moderate growth in element size.
-grow2 : Use high growth in element size.
-grow3 : Use very high growth in element size.
-open : Input configuration is open.
-skin : Input configuration has a structural skin topology.
OPTION PARAMETERS (RARELY USED)
Message_Flag : Message flag.
mmsg : Message flag.
Rec_Flag : List of reconnection flags to reset.
high_order_eval : Discrete geometry high-order evaluation flag.
keep_bodies : List of input body IDs to keep.
m_arearchk : Output area ratio check flag.
mclosed : Input configuration open/closed flag.
mdf : Distribution function flag.
melem : Maximum number of elements.
min_nseg : Minimum number of segments on an individual curve.
mpp : Point placement flag.
mqchkb : Boundary surface quality measure information output flag.
mquad : Quad face combination flag.
n_shmem_buffer : Shared memory buffer size.
rm_bodies : List of input surface IDs to remove.
skin_mode : Structural skin topology mode flag.
NUMERIC PARAMETERS (RARELY USED)
ang_qbmax : Output face angle check maximum angle limit.
ang_qbmax2 : Output face angle check usable maximum angle limit.
ang_qbmin : Output face angle check minimum angle limit.
angdbe : Discontinuous boundary edge angle.
angerw1 : Minimum discontinuous edge angle.
angerw2 : Maximum discontinuous edge angle.
angquad1 : Maximum aligned quad face angle.
angquad2 : Maximum non-aligned quad face angle.
angquad3 : Final maximum quad face angle.
arear_qbmin : Output area ratio check quality limit.
arear_qbmin2 : Output area ratio check quality limit.
cdfr : Maximum geometric growth rate.
gtol : Relative glue tolerance.
length_ratio : Curvature length ratio threshold.
prox_min_scale : Relative proximity minimum spacing.
rel_prox_min_sp : Relative proximity minimum spacing.
qarear_qmin : Output quality function Q check quality limit.
qarear_qmin2 : Output quality function Q check usable limit.