The Effect of Aperture Size on the Cavity Performance of Solar Thermoelectric Generator

Abstract

In this manuscript, a solar cavity packed with thermoelectric generator modules is investigated numerically. The hot plate of TEG modules make the inner surface of the cube, and the cold plate is outside of the cavity, under natural convection. The TEG modules are electrically in series. The solution algorithm using the equations of heat transfer and generated power of TEG modules is developed via MATLAB and simulated under various non-concentrated irradiation levels. The generated power variation in solar thermoelectric cavity shows that as the solar irradiance rises, the generated power increases at a growing rate. The radiation varies from 700 to 1200 W/m2, and the generated power increases from 0.2 mW to 10 mW for side TEGs and up to 30 mW for bottom side TEGs. Studying the effect of aperture size shows that, although the generated power of fully open cavity is 2.25 times higher than generated power in 5×5 cm2 aperture size cavity but its efficiency is 50% lower than small aperture cavity. Heat transfer analysis of cavity depicts the 91% of heat transferred by conduction in cube surfaces and, only 6% and 3% of input energy are lost by re-radiation and convection through the aperture, respectively.

Keywords

• cavity receiver
• thermoelectric generator
• heat transfer
• aperture size