Whether contact time can evaluate the anti-icing properties of superhydrophobic surface - A research based on the MDPDE method

Abstract

Impact freezing of droplets on a cold surface has attracted the attention of scholars. This process is vital for practical problems such as the anti-icing of aircraft wings and cables. Researchers have found that superhydrophobic surfaces can reduce the contact time of droplets and delay nucleation. However, whether contact time can evaluate the anti-icing properties of superhydrophobic surface needs further study. Considering the change in droplet temperature, we vary the dissipative force term of the conservative force in the many-body dissipative particle dynamics with the energy conservation (MDPDE) method. Then combined with the experimental results, a nucleation model of the recalescence rate related to the degree of undercooling is achieved. Finally, we obtain a droplet impact freezing model based on the MDPDE method for the first time, and the impact processes of supercooled droplets on the superhydrophobic surface with three different topological microstructures are explored. Effect of Weber number We on the critical adhesion temperature T* of micropillar surface is reversed when the solid fraction φ is different, and φ is the main factor affecting T*of the microcavity surface. When other conditions are the same, T* of the microridge surface is the lowest. And surprisingly, we observed that the contact time of droplets did not fully measure the anti-icing ability of the superhydrophobic surface.