While it might be tempting to search for a "free download" of COMSOL Multiphysics 3.5a

If you are a student or researcher looking to use COMSOL without the high commercial price tag, consider these options:

COMSOL Multiphysics is a commercial finite element simulation software. Version 3.5a is an older release (from around 2008). There is no legitimate "free download" for the full software unless you are a student using a trial or licensed through an institution. Downloading cracked or unauthorized copies is illegal and risky (malware, legal liability). If you need free alternatives, consider OpenFOAM , Elmer FEM , or FreeFEM .

to request a trial passcode. These trials typically last two weeks and provide full access to the latest version (currently 6.x) and its modules. Workshop Access: COMSOL frequently hosts online workshops