This subpackage contains four validation models for the thermal performance of the PVT_UI collector, an uncovered PVT collector with rear insulation. The models correspond to the four ISO 9806:2013 day types:
Each model compares the simulated thermal output with measured data and provides a detailed breakdown of thermal losses using the quasi-dynamic ISO 9806 formulation. The following loss mechanisms are included:
c4)c5)The model is discretized into nSeg segments to
capture temperature gradients along the flow path. All parameters
are derived from manufacturer datasheets, without calibration.
Validation results show strong agreement for day types 1–3, with thermal energy deviations below 4.2 % and normalized MAE values ranging from 3.3 % to 20.0 %. For day type 4, larger deviations (ΔE = 36.7 %) are observed due to high temperature differences and wind speeds, highlighting limitations in the datasheet-based coefficients under extreme conditions. As the absolute thermal output is low in this case, model limitations have a stronger effect, leading to disproportionately large relative deviations (Meertens et al., 2025).
| Name | Description |
|---|---|
| PVT_UI_Thermal_DayType1 | Test model for Unglazed Rear-Insulated PVT Collector |
| PVT_UI_Thermal_DayType2 | Test model for Unglazed Rear-Insulated PVT Collector |
| PVT_UI_Thermal_DayType3 | Test model for Unglazed Rear-Insulated PVT Collector |
| PVT_UI_Thermal_DayType4 | Test model for Unglazed Rear-Insulated PVT Collector |