TASverter usage guidelines

Remember that STEP-TAS and TASverter are building blocks in the exchange process, but they are not the silver bullet for solving all of your geometric and thermal network exchange and conversion problems!

STEP-TAS was developed when the main space thermal tools worked with thin shell geometries and a limited set of geometry primitives. The STEP-TAS protocol does not handle solid volumes, nor does it handle the less common ANTENNA, OGIVE and TORUS primitives.

TASverter is much stricter in applying the STEP-TAS definitions of valid geometry primitives, etc. than most of the space thermal tools. TASverter makes no attempt to “correct” geometry primitives which are invalid according to the STEP-TAS definition, unlike some other tools that offer “tolerant” geometry, because how one tool “corrects” non-planar quadrilaterals, for example, may differ from other tools, and this may lead to holes or gaps in the overall model.

Model exchange problems can be reduced by planning ahead:

  • Try to use features that are supported by STEP-TAS, e.g. no SOLIDs

  • Try to use features that are supported in both source and target tools

  • Document those areas that relate to limitations within the tools

  • Don’t leave it until model delivery to think about exchange

Prefer ESATAN-TMS 2021+ and SYSTEMA/Thermica 4.9.1+ over TASverter

  • ESATAN-TMS 2021+ and SYSTEMA/Thermica 4.9.1+ offer direct STEP-TAS interfaces

  • They offer the most complete and up-to-date import/export of their geometry models

  • You are advised to used these tools to load/save STEP-TAS files if possible

  • Or you can ask your supplier to generate the STEP-TAS files using these tools

The STEP-TAS protocol does handle shells which are radiatively INACTIVE on both sides, but the source and target tools may handle these shells differently, either as invisible or blocking to the ray-tracing.

The STEP-TAS protocol handles both radiative and conductive activity, so don’t assume that if a surface is radiatively inactive that it is also conductively inactive, and vice versa, and check node numbering.

The STEP-TAS protocol does not recognise that shells may have their sides or activity set to REVERSED, which may result in differences in node numbering and meshing order between source and target models.

The STEP-TAS protocol recognises a limited number of shapes which can be used in cutting operations, but some tools do not support them at all, some tools support some of them, and other tools offer additional shapes not supported by STEP-TAS, such as the oblique extruded polygonal prisms available in Thermica4. Make sure that the cutting shapes in your source tool are supported in both STEP-TAS and the target tool format.

When TASverter was written, only the Esarad-R5 legacy *.erg format supported cutting, so TASverter may convert cutting shapes to real shapes in order not to lose information.

TASverter and the other tools export kinematic joints as fixed geometries, even though the STEP-TAS protocol should handle them.

See the individual tool format pages for tool specific conversion guidelines.