August 2026 critical fixes

User Story 127756: Improve enclosure radiation modeling using the Monte Carlo method for 2D and hybrid 2D-3D turbomachinery workflows

The CPU treatment of Monte Carlo enclosure radiation for 2D and hybrid 2D-3D turbomachinery workflows has been improved.

This change primarily affects enclosure-radiation calculations involving plane stress, hole, bolt, and chocking elements, particularly when radiation is applied to the free or internal edges of these elements.

The updated treatment provides more physically accurate radiation exchange by improving the calculation of view factors, radiative fluxes, and radiation through and around 2D element edges. In particular, it more accurately accounts for effects such as element thickness, transparency, back-face shielding, and self-viewing, which were not always represented correctly by the previous CPU treatment.

As a result, users may observe changes in results for models using these configurations. The most significant differences identified during validation were localized to enclosure-radiation regions involving 2D elements, including plane stress, hole, bolt, and axisymmetric configurations. Depending on the model, changes may be observed in temperature, view factors, net radiative flux, irradiance, or other radiation-related quantities.

The updated 2D treatment was verified against analytical solutions and equivalent 3D configurations. The new results show improved agreement with the expected physical behavior.

Users may therefore observe differences from previous results when running affected 2D or hybrid 2D-3D turbomachinery models. These differences are expected and are a consequence of the improved and more physically accurate treatment of enclosure radiation.

User Story 128342: Implement a fatal error to prevent the use of advanced thermo-optical properties with plane, generalized plane strain, or chocking physical properties

A new validation prevents Thermo-Optical Properties - Advanced modeling objects, regardless of the values defined, from being referenced by Plane, Generalized Plane Strain, or Chocking physical properties. These configurations are not yet fully supported by the thermal solver.

Models using these configurations will now terminate with FATAL ERROR 2039 when the affected physical properties are assigned to a mesh.

This change does not affect:

• Meshes assigned Plane, Generalized Plane Strain, or Chocking physical properties that reference standard Thermo-Optical Properties modeling objects.
• Meshes assigned other physical property types, including but not limited to Thin Shell, Coating, and Solid, that reference Thermo-Optical Properties - Advanced modeling objects.
• Plane, Generalized Plane Strain, or Chocking physical properties that reference Thermo-Optical Properties - Advanced modeling objects but are not assigned to a mesh.

If FATAL ERROR 2039 is issued, the error message will identify all affected physical properties. For each one that requires correction, the user must replace the referenced Thermo-Optical Properties - Advanced modeling object with a standard Thermo-Optical Properties modeling object.