[boffin5]

For a long time I have been working with a simulation involving an aircraft fuselage with a ventral radiator. I am simulating the radiator with a simple cuboid modelled as a porous volume, as part of a chtMultiRegion setup. When I attempt to run the case, it fails, with the message:

"FOAM FATAL ERROR - Plane normal defined with zero length."
How can I resolve this?

When I run the simulation without the radiator as a simpleFoam case, it runs fine, as can be seen with the pressure contours in the attached image. But adding the radiator for a chtMultiRegion case leads to problems. I have attached three more images showing cross sections in different directions to illustrate the installation of the radiator.

Following advice that I found in other posts, I changed the interpolationMethod in fvOptions from cellVolumeWeight to mapNearest. However, the result of this was the case running endlessly, and I finally had to kill it.

I am hoping for advice, especially as this is my graduation case; if I can pull it off, it will be the conclusion of my openFoam tools development, and the beginning of really using it productively!