Dear Shah Akib Sarwar, most of the time these kinds of simulators have folders full of tutorials. This was definitely the best way for me. They are probably far from your application, but they can help you with many other little details!

For some years I used the SPARTA DSMC solver, however, I never tried to integrate it with commercial solvers (I never needed it). Good luck!

Dear Shah Akib Sarwar ,

Regardless of what tool you use, Monte Carlo techniques involve three basic steps:

A time ago, I performed a Monte Carlo simulation to obtain the possible solutions of a predictive model. The idea was to introduce errors to the input variables, and then run the model to obtain the different solutions from that set of inputs. The number of solutions should be statistically significant (>30, depending on each scenario). Finally, the Mean Square Uncertainty index provided information about the impact of the distortions on the model results (Gómez Delgado and Bosque Sendra, 2004).

Best regards

Andres

Dear Günther March, thank you very much for your reply. Could you please suggest some easy-to-learn DSMC solvers for a beginner like me?

Also, have you ever had to couple a commercial CFD solver (used for solving in continuum conditions) with a DSMC solver (used for solving in rarefied conditions)?

Dear Shah Akib Sarwar, as I already mentioned I worked with the SPARTA solver (https://sparta.sandia.gov/). It is a great tool and you can find many tutorials in a dedicated folder. I used this software for free molecular flow regimes, however together with some colleagues we also worked in transition flow conditions.

For what concerns "continuum", I would recommend OpenFOAM (http://www.openfoam.com/). It is widely used and you can find many tutorials even on Youtube.

Good luck!

Dear Günther March , thank you so much for your help! I hope I'll be able to reach out to you again in case I need some more advice on this.