Analysis Of Thermal Losses In Air-Water Interfacial Solar Heating Systems

This paper reports a numerical analysis of solar-driven seawater desalination systems with two configurations: a floating photo-thermal film at the air-water interface with and without an insulation layer located beneath its surface. Heat transfer processes from the film including conduction, convection and radiation have been evaluated at different film temperatures to determine the relative contributions of different heat loss mechanisms from the film. Convective heat transferred to the bulk seawater is found to be the dominant heat loss path, and can be reduced from 6.95 ×10⁷ J/m2∙h to 8.77 × 10⁵J/^m2∙h, a difference of almost two orders of magnitude, by inserting an insulation layer beneath the photo-thermal film. Thus, the addition of an insulating layer is suggested as an important design component to effectively minimize heat losses in air-water interfacial solar heating systems.