Upgrade validation models to ISO 9806:2017 and add conversion tooling for ISO2013/ISO2025

[LoneMeertens]

Context / motivation
See the previous work in the closed issue: #1436
This issue requests extending the validation framework so we can quantitatively compare the detailed (developed) PVT model against the current practice "simplified PVT" models in terms of thermal and electrical power and energy.

[LoneMeertens]

Implementation is currently available on the development branch:
LoneMeertens/IDEAS – issue1473_PvtValidationExt

Summary (main update)
The primary extension in this work is an upgrade of the validation models to use EN ISO 9806:2017 as the canonical parameter set. Implementation has been completed on a dedicated feature branch and a pull request will be opened to merge these changes into issue1473_PvtValidationExt. Because the title of this issue no longer reflects the main change, the issue text has been updated here to summarise the current scope.

What is included in the branch

• Core change: PVT model and corresponding validation framework now targets ISO 9806:2017 quasi-dynamic parameters as the canonical input for the developed PVT model (canonicalises model inputs and avoids cross-standard mismatches).
• Compatibility tooling: An Excel conversion template added under IDEAS.Resources.Data.Fluid.PVTCollectors that:
  • Converts EN ISO 9806:2013 (Unglazed steady-state and Quasi-dynamic) and EN ISO 9806:2025 QD coefficients into the ISO2017 quasi-dynamic parameter set (gross-area basis).
  • Computes the diffuse IAM factor K_d from IAM vs angle (weighted by sinθ·cosθ) and applies the hemispherical reconstruction rule.
  • Applies the nominal G_eff/G scaling used to map the wind–irradiance a6 term from ISO2025 → ISO2017; assumptions and limitations are documented in the template.
  • Uses clearly marked input (red) and output (yellow) cells so datasheet inputs produce auditable ISO2017 outputs automatically.
• Reference::
  Meertens, L.; Jansen, J.; Helsen, L. (2026). Development and Experimental Validation of an Open-Source Unglazed Photovoltaic-Thermal Collector Modelica Model that only needs Datasheet Parameters. (submitted to Mathematical and Computer Modelling of Dynamical Systems).