Abstract:

Herein, a novel type of high efficiency porcelain-aluminum composite solar plate (PACP) was developed, which comprised aluminum alloy matrix plates, flow guide collecting tubes and nanostructure endothermic coatings. The aluminum alloy matrix plate was an integrated structure of circulating pipes and curved fin plates and manufactured through a one-step extrusion process using corrosion-resistant 6063 aluminum alloy. The inner walls of the circulating pipes and diversion collecting pipes were protected by spraying superhydrophobic coating layers. The nanoblack porcelain composite powder was synthesized using black porcelain powders, matting agents, and resin binders. The nanostructure endothermic coating was prepared via electrostatic spraying and a high-temperature curing process. The solar absorptance was up to 0.96. The experimental results showed that the nanostructure endothermic coatings exhibited good thermal stability and would not peel off under long-term adverse environmental conditions. The porcelain-aluminum composite solar plates with an integrated structure exhibited excellent thermal conductivity, and the thermal conductivity efficiency was as high as 0.98. The thermal efficiency of the proposed porcelain-aluminum composite solar collector was approximately 43.6%, which was higher than that of traditional solar collectors, and the manufacturing cost was approximately 14% lower than that of traditional solar collectors. The proposed porcelain-aluminum composite solar collectors have advantages in terms of cost, life, and efficiency and can be used to build large-area solar collector systems to meet current development requirements of the solar energy industry. It has good economic and social benefits and broad application prospects.

Key words: solar energy collectors, porcelain-aluminum composite, nano-coating, thermal efficiency, solar absorptance, electrostatic spraying