SELEÇÃO DA RAZÃO DE PREENCHIMENTO PARA TERMOSSIFÕES APLICADOS EM UM SISTEMA HÍBRIDO FOTOVOLTAICO/TÉRMICO

Abstract

. One alternative for clean energy production are photovoltaic panels, but these have low efficiency, especially when they are performing above their optimum operating temperature. Thus, the use of thermosyphons and heat pipes in PV panels is being increasingly studied, both for panel cooling and to compose a hybrid photovoltaic/thermal (PV/T) system. In this study, an experimental investigation was conducted on the thermal performance of thermosyphons with different filling ratios (30, 40, 50, and 60%) for application in a hybrid PV/thermal system. The investigation consisted in simulating the operation of the devices based on the heating of the evaporator by the Joule effect resulting from the dissipation of electrical energy on a resistive tape (10, 20, 30, 40, and 50W), and the cooling of the condenser by the water flow on its surface (18°C and 1L/min). The thermal analysis of the devices was based on the temperature distribution of the device regions over time, as well as their thermal resistance as a function of the applied thermal load. The results showed that the behavior of the thermosyphons with 30 and 60% filling ratios differed from the behavior of the other two devices, indicating that these filling ratios did not provide the correct operation of these devices. As for the thermal resistance analysis, it was verified that, in general, the 50% filling ratio resulted in lower thermal resistance values for the applied thermal loads, thus concluding that the device with the best thermal performance among those tested was the thermosyphon with a 50% filling ratio.