I need to model two small wires segments (1 cm) in a large tank on either side of a disk that is about the size of a person:

The grid generation gets an error:

geom_decompose: wrong face numbering.

DiskNtankBetweenwires.feaBy shrinking the 'x' dimension (tank +/- 7.5m, wires at +/- 6m):

....the grid will generate:

DiskNtankBetweenwires-gridGenWorks.feaBut if the block (B1) x_min value is set to -7.51 (from -7.5), it fails.

I have tried smaller grid sizes. I tried specifying grid size for each subdomain. What about reorienting the objects?

The wire dimensions are very small compared to 10m. 0.5mm radius. So that's a ratio of 10/.0005 = 2e4... Does this ratio (largest dimension to smallest dimension) have a practical limit? Could some FEATool tolerance be changed by the user that might allow a greater difference (at some processing cost, no doubt).

Unlike some of my models which turn out to be exploratory/learning tools, this one is tied to a specific geometry and experiment hat I want to replicate.

Any hints as to how to go about finding the problem and/or how to solve it would greatly appreciated.

Kind regards,

Randal