firasf1dream wrote:hello guys,
i need please a free and good CFD software to study a design, i am using windows xp and my design will be made by solidworks or catia
If you're looking for a good, free CFD program, you will most likely need to use OpenFOAM if you want to trust the results that you get. Several F1 teams use it (Mercedes and Manor to name a couple), albeit a non-stock version, but I am using it at a team currently with good success. It is open source, which means that there is pretty much zero documentation and instructions on how to use it - the way to get it is to pay for it... which is heinously expensive, and the teaching that they give you is super basic stuff. Youtube vids and running the tutorials and then looking over the log files etc is often enough to get you started.
You will want to export your SolidWorks CAD as an .stl in ascii format with units of meters. Set the lengthscale resolution to the finest, but leave the angular tolerance as default; make sure that you do "not" have "translate parts to positive space" checked.
A really good way to get it on your machine would be to download this:
geekocfd
I have had to compile OpenFOAM myself several times across a few different linux builds and it is always a nightmare. This package is about 4Gb, but it is an OpenSUSE build of linux which comes with pretty much every single package and script that you will need for OpenFOAM already installed and working perfectly!! There is also a post-processor called ParaView which you can use to analyze meshes and do all your other post-processing, along with (I think...) a pre-processor called MeshLab. If they aren't on there, they are free to download anyway.
There are a few cloud computing things out there such as
SimScale which you can use in the beginning that actually solve using OpenFOAM. The way this is set up is that instead of typing a string with a variable to denote say the meshing refinement level you want at some edge, the online app gives you a text box with a little mouse over tool tip that tells you what the setting does. Very handy to get a feel for it... BUT!!... if you are wanting to actually get into the nitty gritty of things and mesh and simulate with very high quality, it isn't enough (for example if you are wanting to change the constants which a particular turbulence model uses to fit your type of analysis). Also, they give you I think 3000hrs free or something? But if you mesh for say 15mins, they deduct 1hr for it anyway - so you chew through it quickly.
OpenFOAM is a challenge, but that's kinda why I like it; it forces you to know exactly what you are doing in order to simulate something... Having said that, in my code, there are literally comments which say "// 3 seems to work here...??" as it is very temperamental at times!! But yeah - start with SimScale and give us a shout if you have any issues
Same to everyone who wants to give it a crack.
