Anti-condensation behavior of bamboo leaf surface (backside) and its bionic preparation
Yanling Wan, Caiyun Zhang, Meng Zhang, Jinkai Xu
Abstract
Abstract Condensation often leads to a decrease in the efficiency of engineering equipment and an increase in energy consumption. Therefore, preventing or delaying condensation on the metal surface is of great significance for practical applications. Here, we report that the main microstructures on the bamboo leaves(backside) are microgrooves, pores and nano needle-like waxy layers, which have good hydrophobicity and anti-condensation performance. Combined experiments and theoretical analyses reveal that, the hydrophobic surface increases the thermodynamic barrier during the condensation process, which makes the liquid droplets appear in a dropwise condensation mode on the surface, thereby increasing the heat transfer coefficient. In addition, when the condensed droplets merge, their low surface energy and nano-needle structure drive their spontaneous bounce. Here, imitated the backside surface of bamboo leaf, an anti-condensation on the aluminum alloy surface is achieved by laser processing and sol-gel method-hydrothermal method.