Maysam Gholampour

Photovoltaic/thermal (PV/T) is an integrated panel simultaneously producing combined heat and electricity. In order to examine the effect of the dimensional, operational, and environmental parameters, energetic and exergetic analyses of solar PV/T air collector systems are investigated. A theoretical model has been developed and the differential equations of energy are numerically solved. To confirm the reliability and accuracy of the present solution, first, comparison studies are performed with the available data in the literature, where good agreement between the obtained values and those existing in the literature was achieved. Then by using the validated model, the effects of the presence of glass cover, packing factor, channel depth, mass flow rate, solar irradiance, collector length, and the fin’s parameters on the performance of the systems have been studied. The results show that exergy analysis is necessary for making better design decisions.

Unglazed transpired collector (UTC) is a kind of solar air heater is used for different applications such as air ventilation, preheating, and crop drying. Passing air through the perforated plate, which acts as an absorber, is the main mechanism of heat transfer and air preheating in UTCs. In order to design UTCs and determine the effective parameters, energy and exergy analyses are performed. A mathematical model which is solved using an iterative method by a computer code has been developed. In order to validate the present model, this solution is compared with numerical and experimental results available in the literature, where a good agreement is obtained. After verifying the model, the code has been used to study the influence of the effective parameters on the performance of the system. The results show that the exergetic analysis is very important to design.

Photovoltaic/thermal (PV/T) system is a kind of solar system that converts solar energy to electrical and thermal energy simultaneously. In this paper, the effect of some parameters, such as packing factor, fin number, and fin height as well as environmental and dimensional parameters on the performance of the PV/T system with natural air flow from the energetic and exergetic viewpoint, has been studied. For this purpose, a theoretical model is developed and validated. Induced mass flow rate and PV temperature are well-predicted, compared with existing numerical data, available in the literature. It is found that thermal efficiency of the PV/T systems decreases slightly with the increase in packing factor, while PV efficiency increases sharply. The first-law efficiency and second-law efficiency of the system increase with the increase in the fin number and fin height. Also, results show that increasing exit diameter is a favorable factor from the first-law efficiency viewpoint, while it has an unfavorable effect on the second-law efficiency.