Numerical simulation data of building integrated solar thermal collectors under diverse conditions

This dataset presents the thermal performance of building-integrated flat solar collectors with a uniform and multiple riser structure. The input data of the numerical model were obtained with the use of the PVGIS tool. Solar radiation and ambient temperature values at slopes 0°, 45°, and 90° were extracted and used as boundary conditions. Numerical calculations were carried using Finite Element (FE) analysis. Three-dimensional transient models were developed to calculate the investigated configurations’ thermal performance based on the environmental temperature, the solar radiation, and the inclination angle. The numerical model was validated with the use of an experimental data set showing a good agreement between the two models with RMSE of 5%. Data of hourly heat flux through the building masonry with the building-integrated solar collector and the average fluid temperature of each system is presented.


Specifications
Energy Engineering, Building physics Specific subject area Heat transfer, Finite Elements Modelling (FEM), transient heat conduction, heat flux, temperature, Building-Integrated Solar Thermal Collector (BIST)  Type of data  Tables, Figures  How data were acquired Solar radiation tool (PVGIS) for boundary conditions [2] Finite elements numerical calculation model (Solidworks Flow Simulation) for heat flux and fluid temperature [3] Data format Analyzed and processed output data Parameters for data collection The geometric parameters of the developed numerical model were considered according to solar collector applications. The solar collector and building materials' thermophysical properties were acquired from the EN 10456: 2007 [4] . The ambient temperature and solar radiation data obtained using the PVGIS tool [2] Description of data collection The thermal medium mass flow rate, which has been used for the solar collector's operation, was obtained from EN 12975-1:2006 + A1:2010 [5] The PVGIS tool was employed to acquire climatic data, which was used to define the external boundary conditions of the simulation models. The climatic data extracted was for the calendar months January (winter), April (spring), July (summer), and October (autumn) and for the orientation's azimuth 0 °, 90 °, 180 °and 270 °.

Value of the Data
• The data provided in this work indicate the impact of design and orientation on the thermal performance of building-integrated solar flat plate collectors. • The variability of the fluid temperature of flat plate solar collector and heat flux through building the wall under variant external boundary conditions. • The methodology presented for developing the building-integrated solar flat plate collector can support researchers in optimizing the design for applications, indicating critical parameters. • The data can also be used as input for numerical models and also be compared to other studies.

Data Description
A summary overview of the numerical results is presented in tables ( Tables 1-3 ). Reference figures ( Figs. A1 -A4 ) demonstrate the three configurations investigated and the building-    (Figs. B2, B4, B6) present the domain meshes of the investigated geometries.
The Reference Figures (B7, B9, B11) present each configuration's riser geometry and Reference Figures (Figs. B8, B10, B12) the fluid flow pattern of each numerical model. Reference     according to the orientation. All the files provided in the Mendeley data are for reproduction purposes, with all the values accessible for edit [1] .

Experimental Design, Materials and Methods
The calculation procedure, was based on a three-dimensional time-dependent finite element numerical modelling. A geometrical model of a building integrated solar collector with various riser configurations was developed. The thermophysical properties of the materials assumed were retrieved from the international standards EN 10456:2007 [4] and  Table 4 . These properties are summarized in Table 6 . As far as the ambient conditions are concerned (temperature, solar radiation), they were defined with the use of the PVGIS tool [2] . The data was processed for different seasons, orientations and slopes (see Table 6 ). The simulation was performed for all four seasons of the year (winter, spring, summer autumn) and for all four main orientations of the building (north, east, south, west) for a solar collector slope of 90 °. Simulations were also performed for the roof for slopes of 0 °and south facing 45 °.
The governing equations employed were the mass, momentum and energy conservation laws, based on the Navier-Strokes approach, for closed-loop forced circulation, expressed as follows: (1)

∂ ( ρu i ) ∂t
∂ρH ∂t Concerning the solid regions of the model, heat conduction was assumed:

Numerical model validation
The validation of the numerical model employed in this study was implemented with the use of experimental data published by Souliotis [6] . Particularly the geometry described in [6] was developed and the boundary conditions, as well as the physics of the implemented numerical model were applied. The validation of the experimental (E) and numerical values (N) was incorporated by the use of the root mean square deviation (RMSD) formula.
In Fig. 5 , the agreement between the experimental and numerical values is presented. As calculated from the obtained values of experimental and numerical cases, the RMSD is 5.01%, a value which is considered satisfactory [7] .

Ethics Statement
No ethical issues are associated with this work.

Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article.

Supplementary Materials
Supplementary material associated with this article can be found in the online version at doi: 10.1016/j.dib.2021.107470 .