Tanks

[joergbrech]

Description

This PR adds fuelTanks. These tanks consist of several vessels. Each vessel can be made up of several skin layers to represent composite materials. There is usually a vacuum between the vessels. A vessel is constructed in the same way as a fuselage - in principle like a matryoshka of fuselages.

Note: It is still an open CPACS discussion how to realize varying skin thicknesses of a vessel. This would also affect the fuselage and will therefore be a separate issue.

What is new compared to fuselage or similar elements with parentUID: The tank vessels are direct child elements of the fuelTank element, and thus not referencing to this via parentUID. Furthermore, they should not only follow the translation of the fuelTank element, but also the scaling and rotation. Therefore, additional constructors are added to CTiglRelativelyPositionedComponent, along with methods to apply scaling and rotation to the transformation matrix.

The added code follows the proposed clang settings.

Fixes #969.

How Has This Been Tested?

Thorough testing has been implemented for C++ and Python code:

• test file: simpletest-fuelTanks.cpacs.xml
• cpp tests via tiglTanks.cpp
• Python tests via test_fuelTanks.py

The tests cover all elements of the fuelTanks added to CPACS. Perhaps the Python tests in particular go a bit beyond what would only concern the tanks, as they also test the correct export of the generated classes. If automated Python tests for the generated classes are part of future TiGL releases, this could be removed. For now, I feel a bit more comfortable as it is not always clear to me how exactly the configuration.i is built.

Screenshots, that help to understand the changes(if applicable):

Checklist:

Task	Finished	Reviewer Approved
At least one test for the new functionality was added.	yes does not apply	OK
New classes have been added to the Python interface.	yes does not apply	OK
The code is properly documented with doxygen docstrings	yes does not apply	OK
Changes are documented at the top of ChangeLog.md	yes does not apply	OK

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EDIT: This PR is just a replicate from #1057, because our CI has problems with PRs from forked repos, see #1059. Thanks @MarAlder for all the work!

[joergbrech]

Very nicely done! This is a great addition to TiGL. Thank you very much @MarAlder for the implementation and also @sfreund-DLR for the input on the isotensoid contours.

[sfreund-DLR]

Thank you for all implementations and optimization of the code!!

[lin22-hub]

Hello, everyone! May I ask if the visualization of the fuel tank has been completed? I didn't see the fuel tank when I used the test file.

[joergbrech]

It has been merged into the main developement branch after the latest TiGL release. It will be part of the upcoming TiGL release. If you need this functionality earlier, you would have to build TiGL yourself.

If you are using Windows, you could use one of the build artifacts from our continuous integration pipelines, e.g.

https://github.com/DLR-SC/tigl/actions/runs/16159391922/artifacts/3492003743

Note that the artifacts are not retained for long, but we have nightly builds, so if the link is invalid, check for pipeline artifacts here on Github under the "Actions" tab.

[MarAlder]

⚠️ Also remember that tanks are not visualized per default. In TiGL viewer, you need to select them via Draw > Aircraft > Draw any Component.