So a couple of days of downloading multiple CAD softwares from solidworks to freeCAD has finally yielded some results! The STL file has been converted and modified as well as split so it turned out pretty good! Needs further refinement but otherwise good to go and has translated the much needed ground elevation data as well.
So the software I used is Autodesk’s MeshMixer. Due to how annoying STL files are, you first need to import the STL file into MeshMixer to then convert the geometry into a solid body via the edit function. Converting it to a solid body will require you to define two things, the solid accuracy and mesh density. Solid accuracy is where the definition of the solid body comes from and making that as small as possible in terms of the cell size will yield better and better results, however at increased computational cost in terms of size and time of course. Mesh density I’ve haven’t had time to play around so you can try increasing that to see what the results are but I set that to the highest level of fineness regardless.
Oh and do note that you also have to select the way the program creates the solid body. For my purposes, edge accuracy is important so that is the mode (sharp edge preserve) I have selected.
Once that is complete you can split the faces natively in the program under edit “Generate Face Groups” and you’re good to edit the geometry within the software or export it out as a solid body to your preferred CAD software.
I exported my file from there as STL and uploaded onto SimScale where I performed a STL face splitting operation that was successful as you can see in the picture.
Hope this helps anyone who needs a free and easy alternative to modifying STL files for simulations. My geometry here needs to be very accurate so getting what you want would probably require specific values tailored to your needed accuracy when it comes to generating a solid body.
Edit: Just to add, this method is preferable for smaller less complex geometries. Too large of a geometry and you will have issues performing the STL face split.