[WIP] Enabling multi-passage duplication for turbomachinery cases.

[FabianYan2010]

Proposed Changes

Multi-passage or full-annulus simulation is very important for turbomachinery case. For example, say one wants to simulate the circumferential features like rotating-stall or inlet distortion effect. Usually one first conducts single-passage RANS computation, then starts multi-passage or even full-annulus URANS from that converged single-passage solution. To do this in SU2, one meets two problems:

1. Replicate the single-passage grid to user-defined number of passages (including full-annulus)
2. Replicate the single-passage solution

The proposed changes solve the two above mentioned problems. This function is one of a series of features that enable SU2 to run URANS for turbomachinery cases, which have been shared to the SU2-Turbo group recently. This function has been used for my research for almost one year. If necessary, I could add simple test cases as well.

Related Work

Resolve any issues (bug fix or feature request), note any related PRs, or mention interactions with the work of others, if any.

PR Checklist

Put an X by all that apply. You can fill this out after submitting the PR. If you have any questions, don't hesitate to ask! We want to help. These are a guide for you to know what the reviewers will be looking for in your contribution.

• [x] I am submitting my contribution to the develop branch.
• [x] My contribution generates no new compiler warnings (try with --warnlevel=3 when using meson).
• [x] My contribution is commented and consistent with SU2 style (https://su2code.github.io/docs_v7/Style-Guide/).
• [x] I used the pre-commit hook to prevent dirty commits and used pre-commit run --all to format old commits.
• [ ] I have added a test case that demonstrates my contribution, if necessary.
• [ ] I have updated appropriate documentation (Tutorials, Docs Page, config_template.cpp), if necessary.