When you explain your project to someone what do you choose between:

• I did this simulation because..., I considered only ...
• I have done this simulation because ..., I have considered only...

To me, PS is used when the project is finished. Whereas PP when the project is ongoing. Except if I say "I did it at the beginning" when there is a time reference.

Is it correct? But I think that PS could be good everywhere because if this is not finished we would say "I am currently doing"...

If the project is to do 3 simulations, and the 2 first are finished and I just started the last one. If I tell to someone my work. I can say "I did the simulation 1 and 2" ? (PS), because they are considered finished.