Error when combining objects (subtracting object from flow block)

Greetings,

I am attempting to subtract a submerged object from a block.  In the following configuration the result is a useable flow domain:
before combining:

after combining:


If the block size is increased from -1:1, -1:1, 0:2 to -30:5, -2:2, 0:3, the same combination does not yield a useable domain.  The submerged object becomes sort of a partial shell:
before combining:

after combining:


I have tried first combining with the smaller block and then augmenting with blocks on the sides and top, but the result is the same.  Here's a link to the relevant model file:

https://drive.google.com/file/d/1ysTSsLbAubOsbxlXdsm-6Jh3KVTNxgrO/view?usp=drive_link

Any help would be appreciated!

Thank you for reporting, that clearly looks like an issue with the geometry engine somehow. While waiting for model access.

As a temporary workaround I guess would be to first perform the subtraction with the small block, and then add the surrounding region (potentially with a hollowed out larger block). The drawback would be some extra internal subdomains and boundaries, but I don't think it should affect anything too much (and could potentially be useful to assign smaller mesh size closer to the submerged object).

Following up, this issue is due to deduplicating boundaries for geometry object visualization (to save resources), in particular since here the scale difference of the object were quite large it became an issue with the current algorithm. However, the issue is just with geometry boundary visualization, so you can still mesh, and later show and set boundary conditions on the correct geometry. That said, from a simulation perspective it still might be better to have an inner finer block, with an outer coarser one, depending on the simulation. Thank you for submitting the issue report, a fix will be included in the next update later in the year.