Numerical analysis of laser ablated structural size effect on enhanced anti-icing property of TC4 surface**Research supported by Fujian Provincial Science and Technology Programme (Industry Oriented Key Project, No. 2020H0006), Guangdong Basic and Applied Basic Research Foundation (2020A1515010519).

Superhydrophobic surface with micro/nano structures has attracted extensive attention because of its excellent performance in passive anti-icing strategy. In this study, a 2D Computational Fluid Dynamics model was proposed to simulate the icing process of droplet on surface at low temperature by coupling the Volume of Fluid model with solidification/melting model. Then, the icing process of droplet on surfaces with different micro structures were simulated and compared. Furthermore, the samples with different micro-nano structures were obtained by laser ablation and their anti-icing performance were measured. Results showed that the icing time of bouncing droplet on the surface with micro/nano structures is significantly delayed by seven times, where the nucleation rate is related to the contact area of solid-liquid phases. It is also found that the larger size of the air cavity brought by the structure is more conducive to obtain enhanced anti-icing performance. Furthermore, the anti-icing mechanism of superhydrophobic surface was revealed by investigating variations in solidification/melting contour and solid volume fraction.