Experimental Investigation of the Performance of a Transpired Solar Collector Acting as a Solar Wall
Abstract
It the current energy context it is necessary to implement highly efficient and cost-effective systems in order to reach indoor comfort conditions with minimum energy consumption. This paper aims to analyze the performance of an unglazed transpired solar collector (UTSC), which represents a building envelope element, and to assess the efficiency of two types of external metal cladding: with circular orifices and with lobed orifices. Several experimental campaigns were conducted using different approaches and the results are very interesting: the metal plate with lobed orifices increases the efficiency of the solar collector, providing an enhanced thermal transfer and higher exhaust temperatures. The use of lobed orifices rises the outlet air temperature with 10% more than in the case with circular orifices by enhancing the heat transfer between the metal plate and the air flow due to the more complex dynamic of the lobed flows near the metal absorber. The rise in temperature in case of using lobed orifices is 22.9°C and the metal plate temperature is 64.5°C. An experimental study regarding the implementation on phase changing materials (PCM) in transpired solar collectors was also conducted.