DL_MESO_LBE utilities¶
As well as the main LBE code (DL_MESO_LBE), DL_MESO comes with a number of utilities that can be used to help set up DL_MESO_LBE simulations and process some of the outputs.
The source codes for all of these utilities can be found in the LBE/utility directory of the DL_MESO package, all of which need be compiled using a C++ compiler (e.g. g++). All LBE utilities (along with the DPD utilities) can be compiled using the Makefile in the WORK directory with the instructions shown in the DL_MESO Ready, get set, go guide. Each utility can be run with a command-line flag -h, e.g.
./utility.exe -h
to provide details and show the available command-line options.
lbeinitcreate.cpp
This utility helps to create a lbin.init file to specify initial conditions for a LBE simulation other than uniform values specified in the lbin.sys simulation setup file. In particular, it can be used to add circular/spherical fluid drops and/or rectangular/cuboidal regions with fixed values of solute concentration or temperature.
The source code for this utility is normally compiled to produce the executable init.exe, and can be run with the command:
./init.exe
It requires a lbin.sys file to be present in the directory where it is run. From this file it will read in:
- the number of dimensions (2 or 3)
- numbers of fluids, solutes and temperature fields
- initial and constant fluid densities
- initial solute concentrations and/or temperature
- the size of the grid
After this, the utility will print relevant information to the screen before prompting the user to enter information about fluid drops and regions of solute concentration or temperature to be added to the simulation. Based on user input, the utility will then create the lbin.init file to include the drops and regions of constant concentration/temperature in place of default values at the relevant grid points.
lbplot3dgather.cpp
After a parallel DL_MESO_LBE calculation producing multiple Plot3D output files per timestep, this utility pulls those files together to create a single file per timestep.
This utility is normally compiled to produce the executable plot3d.exe, and can be run with the command:
./plot3d.exe
As well as the lbout*.q Plot3D solution files and lbout*.xyz or lbout*.xy grid files, this utility also requires the lbout.info file generated by DL_MESO_LBE to read in information about the contents of the files.
No user input is required: the utility will find all of the available solution and grid files, and then create combined lbtout*.q solution files and an accompanying lbtout.xyz or lbtout.xy grid file.
lbevtkgather.cpp
After a parallel DL_MESO_LBE calculation producing multiple XML-style VTK output files per timestep, this utility creates linking files that can be opened directly in Paraview to visualise the simulation.
This utility is normally compiled to produce the executable vtk.exe, and can be run with the command:
./vtk.exe
As well as the lbout*.vts VTK files, this utility also requires the lbout.info and lbout.ext files generated by DL_MESO_LBE to read in information about the contents of the VTK files and the grid extents they include. The utility will then create a series of lbout*.pvts files (one per timestep), which include references to the original lbout*.vts files and where they fit inside the overall grid.
No user input is required by default, although if the output files were created using a customised version of DL_MESO_LBE that only outputs one property in the files (e.g. one fluid’s density), command-line options are available to tell the utility which property to include in the lbout*.pvts files:
-ato include all properties (densities, mass fractions, concentrations, temperature) for all fluids, solutes and/or temperature fields-dto include a single fluid density-fto include a single fluid mass fraction-cto include a single solute concentration-tto include temperature only
lbedumpinit.cpp
This utility creates a lbin.init file for a new LBE simulation from the lbout.dump simulation restart file of a previous one.
The source code for this utility is normally compiled to produce the executable dump_to_init.exe, and can be run with the command:
./dump_to_init.exe
No user input or other files are required: the lbout.dump file includes all the information needed to find the macroscopic properties (velocity, densities, concentrations, temperature) at each grid point. The utility will create the lbin.init file and also report the timestep number for the lbout.dump file.
lbedumpvtk.cpp
This utility creates an XML-style VTK file from a lbout.dump simulation restart file, which can be used to visualise the simulation at that point.
This utility is normally compiled to produce the executable dump_to_vtk.exe, and can be run with the command:
./dump_to_vtk.exe
No user input or other files are required: the lbout.dump file includes all the information needed to find the macroscopic properties (velocity, densities, concentrations, temperature) at each grid point. The utility will create a lbdump.vts file, which can be opened in Paraview, and also report the timestep number for the lbout.dump file.