High-speed airflow influence on adhesion performance of fibrillar adhesive

Bio-inspired adhesives have been widely studied in various fields, including attachment and grasping technologies in sea, land, air, and space. However, current research primarily focuses on static and quasi-static scenarios, necessitating further exploration in achieving adhesion on high-speed moving objects, such as railroads and automobiles. In this study, we explore a representative adhesive system comprising a fibrillar adhesive layer and a backing structure contacting with a smooth substrate in high-speed airflow. The investigation into adhesion performance was conducted by finite element analysis, theoretical analysis, and experimental approaches. Our findings indicate that the impact of high-speed airflow on microfiber structure deformation primarily manifests within the initial 1–2 rows on the windward side, yet remains insufficient to significantly influence adhesion. The adhesion capacity of the adhesive composite in high-speed airflow is mainly determined by the elastic modulus of the backing structure and the deformation offset, exhibiting a straightforward linear relationship with their product. Moreover, an optimization strategy of adding a cowling to the adhesive composite with soft backing was proposed to preserve its high loading capacity. These findings present a comprehensive understanding of the loading mechanism of fibrillar adhesive composite in high-speed airflow and provide new insights into robust reversible adhesion design for related technologies.