Numerical investigation of building integrated solar thermal collectors under diverse conditions

The scope of this study is the investigation of the thermal performance of building-integrated solar flat collectors with a uniform and multiple riser structure. The effect of dynamic operating parameters such as the environmental temperature, solar radiation, the inclination angle and further model modifications to the fluid inlet, outlet and riser are studied. Numerical calculations were carried out using Finite Element (FE) analysis. Three-dimensional transient models were developed to calculate the thermal performance of the investigated objects. The study revealed increased efficiency for the multiple-riser configuration. Under all boundary conditions, the highest fluid temperatures occur in the south orientation during autumn and winter and in the west during spring and summer. The thermal assessment comparison between the roof installed and vertical solar collectors were performed, and the differences throughout the slope angles were distinguished. The results showed that a building-integrated solar system acted as a shield barrier, and provided heat to the building structure.