ParaView

To install it download the binary file from the ParaView website, un-tar it. To call in the correct way ParaView, after having downloaded binary file, put in your ~/.bashrc file the installation directory and source the file after that, so it each time the terminal is called the path will be registered and you can call ParaView with command line command; ParaView.

export PATH= <installationPath>/ParaView-<ParaViewVersion>/bin:${PATH}

and then make this modification active for the same session

source ./bashrc

There is the need to create a dummy file in the working directory to make ParaView be able to read the OpenFOAM® format.

touch <nameOfTheCase>.foam

If ParaView is installed on GNU-Linux system, it is convenient call it with command

paraview <nameOfTheCase>.foam &

The tag & keeps the program in background so you can continue to use the same terminal page. In Windows Subsystem for GNU-Linux (WSL) it is enough terminate the installation and run the executable;

ParaView.exe <nameOfTheCase>.foam

When ParaView return errors in reading, it could be possible to solve it changing the case format, convert the result of the simulation in the VTK format (Visualization Tool Kit), it makes easier the manipulation the file and the properties contained on in. The following command convert the format from the OpenFOAM native one to VTK one:

foamToVTK

WARNING: If you use pressure-based solver as simpleFoam, it is necessary multiply the pressure for the density!!!

Parallel visualization in local machine

It is possible to parallelize the visualization task to deal with big cases in your local machine, the simplest way is to enable the “Auto MPI” mode through the following actions:

paraview –> Edit –> Settings –> Enabled advanced options (the cogwheel up right) –> Scroll down (or search for) “Multicore Support” –> Enable AutoMPI and set the number of cores –> restart ParaView.

Huge data-set visualization

When the user cope with a huge amount of data, it is necessary the usage of a cluster to help manage the load and distribute it. However even a single machine user benefit from these techniques.

NVIDIA IndeX™

A plug-in from NVIDIA called NVIDIA IndeX™ helps in resolving the problem. It is a volume visualization tool, that takes advantage of the GPU’s to deliver real-time performance on large datasets by distributing visualization workloads across a GPU-accelerated system. If you have installed ParaView using a binary package provided by Kitware, then the plugin is already included and it is possible to load via:

paraview –> Tools –> Manage Plugins –> pvNVIDIAIndex –> Load selected

Trouble shooting commons problem

ParaView in latest version require drivers for OpenGL => 3 and in certain OS (such as CentOS 7) this is not compatible, hence if the installed OpenGL driver are not supported, try to launch ParaView telling to follow the MESA drivers:

MESA_GL_VERSION_OVERRIDE=3.2 paraview

Otherwise:

paraview –mesa

Same if you need to use ParaView in a headless mode and a graphic card is not available, but you still want to render on the server. You can build ParaView with these options to overtake the problem:

cmake -GNinja -DVTK\_OPENGL\_HAS\_OSMESA=ON -DVTK\_USE\_X=OFF -DPARAVIEW\_USE\_QT=OFF ../\<locationParaViewSourceCode\>