An experimental investigation on winter heat storage in compact salinity gradient solar ponds with silicon dioxide particulates infused paraffin wax

Abstract

Silicon dioxide particulate which is also called silica, owing to its cost-effective synthesis, abundant availability, and high heat transfer capabilities, present an eco-friendly solution with immense potential for diverse applications, including solar heating systems. This novel study explores the integration of silica microparticles infused in paraffin wax in a compact salinity gradient solar pond for enhanced heat storage during the winter season. Leveraging their biocompatibility, facile functionalization, and expansive surface area, silica microparticles exhibit outstanding attributes such as photoconductivity, optimal thermal expansion, corrosion resistance, and enduring durability, all of which synergistically contribute to system efficiency. During the first day, without any heat storage medium, the three distinctive zones of the compact salinity gradient solar pond exhibited temperatures of 31.2 °C in the upper convective zone, 32.8 °C neutral convective zone, and 35.7 °C in the lower convective zone respectively. Experimental investigations are conducted, employing both paraffin wax and silicon dioxide microparticles as augmenting agents to amplify heat storage capacity within the compact solar pond setup. While using paraffin wax without silica particulates the lower convective zone temperature was 4.2 % lower because of heat storage. The incorporation of trace amounts of silicon dioxide microparticles within paraffin wax establishes a novel hybrid approach. The outcomes highlight the profound impact of this hybridization on thermal characteristics, resulting in a discernible improvement in the compact salinity gradient solar pond's heat behavior. Notably, the phase change material introduces a temperature enhancement of approximately 1.5 %, and the amalgamation further elevates the temperature retained to 56 °C within the lower convective zone. An optimization analysis underscores the pivotal role of the solar pond configuration in dictating temperature changes, surpassing the influence of time considerations. This research underscores the transformative role of silicon microparticles in optimizing thermal performance within compact salinity gradient solar ponds, unlocking avenues for enhanced winter energy utilization.