Exchanging Thermal Models with STEP-TAS 2003-01-2605
Over the last years the open data exchange standards STEP-TAS (Thermal Analysis for Space) and STEP-NRF (Network-model Results Format) have been developed under ESA funding. Both standards are based on ISO 10303/STEP.
STEP-TAS converters have been implemented in many different thermal-radiative analysis packages, both in Europe and the US, in either pre-production or prototype versions. For practical use the converters needed to gain robustness and scaleability to exchange large models. In order to achieve the required industrial robustness and at the same time to lower as much as possible the barriers to implement the protocol, ESA has taken the following measures:
Simplify considerably the NRF and TAS protocols, taking into account all lessons learned from the earlier developments.
Develop TASverter, a STEP-TAS based stand-alone thermal model converter tool, which can read and write ESARAD, THERMICA and TRASYS models, and serves as a reference implementation of STEP-TAS converters. This software — written in the Python scripting language — is being made available as a PC/Windows executable for download from www.estec.esa.int/thermsoft free of charge.
Start a web-based STEP-TAS validation and verification process, including a version controlled test suite, both comprising a complete set of elementary test cases and a number of comprehensive real-world thermal models.
Develop an open source library to build STEP-TAS converters in a cost-effective way, without any dependency on third party software. This library is being made available through the above website as well.
The paper and presentation discuss the state of STEP-TAS implementations for thermal-radiative model exchange. Also new developments to support exchange of thermal lumped parameter network models (e.g. ESATAN, SINDA-G, SINDA-85) including unit conversion (e.g. Imperial to SI) are shown. These have been verified extensively for a number of ISS and STS thermal interface models.