ANALYTICAL AND NUMERICAL ANALYSIS OF MELTING ICE SLIDING ALONG INCLINED SUPERHYDROPHOBIC SURFACE WITH AIR SLOT

A physical and geometric model for the sliding process of an melting ice along superhydrophobic (SH) surfaces with air slot structures in this article. By analyzing the micro-shear flows of molten liquid layers between the ice layer and SH surfaces, a double series equation (DSE) was established by using the "stick-slip" boundary condition of SH surface to obtain the analytical and numerical solutions for the micro-shear flows. Based on this, the velocity fields of the micro-shear flows and the sliding velocties of the ice layer under the different air slot ratios (a), the inclination angles (α) and the thickness of the molten liquid layers (δ) were investigated. The results indicate that the thinner the molten liquid layer or the larger the air slot ratio is, the more significant is the deviation of the micro-shear flow field on the SH surfaces from the planar shear flow. The slip velocity gradients have sudden changes and reach their peaks at triple contact lines. Increases of a, α and δ will lead to non-linear increases in the hyperslip velocities. When δ ≥ 1, the hyperslip velocities tend to the values calculated from the function of asymptotically analytic solutions. Based on the parameter values taken in current study, it is found that the increments in ice sliding velocities account for more than 60% of the total sliding velocities at a = 0.95, δ = 0.2 and a = 0.9, δ = 0.1, which indicate that the ice sliding velocities mainly come from the contributions of hyperslip velocities. This study provides a reference for the fluid physical processes in current SH de-icing applications.