Software licenses tend to make things complicated. If a licensed software product is everywhere - like Microsoft Windows - it is rather easy for people to adapt and stay away from complications. But if the software product is more specialized than that, potential users tend to split into

  • those whose tasks warrant a license fee to be paid for, and
  • those who would like to use the software but who cannot raise money for it.

Whether its members want it or not, licensed software users form an exclusive club.

Such exclusivity counteracts the natural tendency of people to be generous and helpful. As I see it, there is a clear difference between guarding the intellectual property (IP) of your job and the intellectual property of the tools you that use for your job. Guarding job IP is necessary for business - being forced to keep your tools away from potential collaboration partners may inhibit business.

Each stakeholder has to make a choice. Until license-bound software vendors adapt for real, I'll stick with the open source world. Those guys seem to be more generous, to have more fun and to be less inhibited in their work. Let me give you some examples.


Computing power in the cloud is surprisingly cheap. You may get a feeling of being surrounded by introductory offers, but only time will tell the truth on this. Anyway, the German company SimScale has since 2012 offered a cloud solution for both structural and flow analysis. SimScale only applies software which is free to use and that choice allows them to offer their services free of charge for anybody who is willing to make their simulations public. That is, you can start doing simulations today with no prerequisites at all - you do not need prerequisite funding and you do not need prerequisite knowledge (although the latter helps...). SimScale has simply adopted the same business model as the one used by some popular antivirus vendors. Now, that's generosity!


Code_Aster is a structural analysis software product still sponsored and used by the national French electricity agency EDF. That simple fact explains the feature richness and quality of Code_Aster. In 2001, it was released as free software under the terms of the GNU General Public License. As for generosity, you may on the user forum pages of Code_Aster experience Frenchmen providing guidance in English...

Having visited the Salome-Meca User's Days of both 2018 and 2019, I find it worth mentioning that

  • attending this annual conference about an open source software system is entirely free (lunch included)!
  • by using headphones distributed before the conference start, you can hear all statements in French translated simultaneously into English - and the quality of the translation is very high.


OpenFOAM is a simulation software system for fluid flow analysis. In the world of mechanical simulations, probably no other open source system has achieved a greater business impact. Unfortunately, development has split into (at least) two main branches with repositories on and, respectively. On both sides of all fences, however, the amount of competence, quality and dedication is overwhelming.

ParaView (and VTK)

The way ParaView and VTK are organized is the opposite of that of OpenFOAM. Here, two separate open source software systems are maintained by the same organization. The result is arguably the world's best postprocessor for mechanical simulations. ParaView is feature-rich, very nicely organized with VTK as a distinct sublayer, offers both scripting and journaling, and the entry level documentation is impressive.

midas MeshFree

midas MeshFree is a structural analysis CAE package which is not open source. I have chosen to include it anyway on this "generosity" page because of their "freemium" pricing strategy. Every person with a Windows computer and an Nvidia graphics card can for an unlimited period of time apply midas MeshFree to

  • import CAD models from as many sources as any high-profile CAE system (standard 3D formats are handled at no cost, but you will have to pay for the ability to import native files from the major CAD packages directly)
  • avoid meshing altogether
  • do linear analysis on heat transfer, linear elasticity (including modal analysis) and linear thermoelasticity

The documentation (including a well thought-of introduction for people who have never done CAE before), the user interface, the feature set and the postprocessing capabilities are basic, but clear and no-nonsense.

FreeCAD and Open CASCADE

Even though simulation as a discipline lies somewhat away from CAD as a discipline, you sometimes need to tweak or generate geometry when doing a simulation. Today, licensed CAD tools are much more affordable than licensed simulation tools. Therefore, if you are not a purist by temperament, you may have your geometry processed by many tools. But Open CASCADE is a well-thought-of, full-featured alternative to closed-source geometry kernels, and FreeCAD is emerging as an open source CAD system built on top of Open CASCADE.


Gmsh is a rather nerdy meshing tool which is quite feature-rich, uses Open CASCADE as its geometry kernel and comes with its own scripting language. And it is of course open source. I want to mention Gmsh here because the authors have bothered to explain GNU licensing to people with only a layman's interest in the subject:

In short, this means that everyone is free to use Gmsh and to redistribute it on a free basis. Gmsh is not in the public domain; it is copyrighted and there are restrictions on its distribution (see the license and the related frequently asked questions). For example, you cannot integrate this version of Gmsh (in full or in parts) in any closed-source software you plan to distribute (commercially or not). If you want to integrate parts of Gmsh into a closed-source software, or want to sell a modified closed-source version of Gmsh, you will need to obtain a different license. Please contact us directly for more information.


I have only recently recognized the importance of handling uncertainties as rigorously as the well-defined problems that have occupied most of my professional career. OpenTURNS is an open source package which handles many relevant problems in this area. Combined with dimensional reduction of otherwise complex and time-consuming simulations, you have a very strong tool at your disposal - still without paying for any software license at all.

OpenTURNS may do the same to the processing of stochastic variables as this method does to time series predictions.

Dr.-Ing Ackva Ingenieurbüro für Mechanik

This company provides services in connection with Code_Aster. I want to mention them on this list because they helped me pass an obstacle encountered while attempting to make Code_Aster work. Reading this text on their website made me feel in good hands and on the right track:

The use of astk and the creation of your first .export file is the most troublesome, unpleasant, tedious and painful task which you have to survive. Please do not swear, do not blaspheme. There is no one who has got it easier. Find consolation in the future benefits when working with Code-Aster.

FEA for All

"" appears to be a new website authored by Cyprien Rusu. I immediately felt at home the day I found it.

My own article collection

fits into this context, too.

Some off-topic honorable mentions

Some manifestions of generosity belong to a league of their own.

Otherwise, one could always mention Margaret Douglas, mother of the economist Adam Smith (1723-1790), who never married. She generously took care of her son while he pinned down his theory of self-interest as the driving force of society...

When in private, I have a soft spot for the performing arts. In this context, I want to mention Amanda Palmer. Her pursuits may seem to wander inexplicably in many directions. However, I see "generosity" as a feature which joins and explains them all.

As I mention Luvvie Ajayi for my benefit here, I shall of course also mention her for her benefit on the webpage that you are now reading.

And then there is humor, of course. I guess I am not the only person in the world who would not have survived some dire experiences without humor to light things up. I have tried to find and credit the author for the joke to follow, but right now, I cannot find him (I am rather sure of the gender). I recall an organ player at the Stephansdom in Vienna who on his private homepage came up with this one:

Dear guest: Unfortunately for you, you have now excluded yourself from a rapidly growing community in cyberspace: those who have never visited this webpage...


A pretty picture. For more pretty pictures, see here.

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