Predictive Model for Ice Formation on Superhydrophobic Surfaces

Abstract

The prevention and control of ice accumulation has important applications in aviation, building construction, and energy conversion devices. One area of active research concerns the use of superhydrophobic surfaces for preventing ice formation. The present work develops a physics-based modeling framework to predict ice formation on cooled superhydrophobic surfaces resulting from the impact of supercooled water droplets. This modeling approach analyzes the multiple phenomena influencing ice formation on superhydrophobic surfaces through the development of submodels describing droplet impact dynamics, heat transfer, and heterogeneous ice nucleation. These models are then integrated together to achieve a comprehensive understanding of ice formation upon impact of liquid droplets at freezing conditions. The accuracy of this model is validated by its successful prediction of the experimental findings that demonstrate that superhydrophobic surfaces can fully prevent the freezing of impacting water droplets down to surface temperatures of as low as -20 to -25 °C. The model can be used to study the influence of surface morphology, surface chemistry, and fluid and thermal properties on dynamic ice formation and identify parameters critical to achieving icephobic surfaces. The framework of the present work is the first detailed modeling tool developed for the design and analysis of surfaces for various ice prevention/reduction strategies.

The icephobic performance of alkyl-grafted aluminum surfaces

“…Significantly delayed ice formation [3,10,12,13,15,16,23,26] and reduced ice adhesion or accumulation [3,10,[15][16][17]19,21,25] have been reported for various SHSs. Theoretical models have also been developed, demonstrating how SHSs can delay ice formation from impinging water droplets [9,11,13], which is in good agreement with experimental work [3,14,25,26].…”

“…Therefore, the prevention and control of ice accretion is of high potential in all these fields of human activity. The design and use of surfaces/coatings with minimum ice adherence and reduced ice accumulation is still actively considered as the most appealing and universal approach to the problem [3,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Most of the existing studies on anti-ice surfaces are focused on the reduction of ice adhesion strength [1,[5][6][7][8]10,[19][20][21][22][23][24] or delayed ice nucleation/formation [3,9,12,13,23,25,26].…”

“…Most of the existing studies on anti-ice surfaces are focused on the reduction of ice adhesion strength [1,[5][6][7][8]10,[19][20][21][22][23][24] or delayed ice nucleation/formation [3,9,12,13,23,25,26]. Therefore lately the research in this area has been chiefly focused on the use and development of superhydrophobic surfaces (SHSs) for preventing ice formation and accumulation [4,[9][10][11][13][14][15][16][17][18][19][20][21][22][23][25][26][27][28][29]. Significantly delayed ice formation [3,10,12,13,15,16,23,26] and reduced ice adhesion or accumulation [3,…”

Supercooled Water Droplet Impacting Superhydrophobic Surfaces in the Presence of Cold Air Flow

“…Additionally Gibbs free surface energy is defined based on the melting temperature of water, , water-ice surface tension, γ , latent heat of fusion, , solid-liquid or gas-liquid interface temperature, , and geometrical factor, , as illustrated in Equations (2) and (3) [17,40]. increasing Ohnesorge number still air This phenomenon can be further elaborated through classical ice nucleation theory combined with thermal transport analysis.…”

“…Larger solid-liquid interfacial area of impacting drop causes a significant increase in the heat transfer cooling rate [15]. Furthermore, both induced homogeneous nucleation [16] (i.e., due to evaporation cooling) and heterogeneous nucleation (solid-liquid interaction) [17] are related to liquid interface temperature. In fact, in real atmospheric cold conditions, induced homogeneous nucleation can happen even above the critical temperature of homogeneous nucleation (i.e., −37 • C) [18,19] due to the presence of air flow which systematically increases the rate of evaporation cooling at low and high humidity environments [16].…”