Dynamic Mitigation Mechanisms of Rime Icing with Propagating Surface Acoustic Waves

Abstract

Ice accretion on economically valuable and strategically important surfaces poses significant challenges. Current anti-/de-icing techniques often have critical issues regarding their efficiency, convenience, long-term stability, or sustainability. As an emerging ice mitigation strategy, the thin-film surface acoustic wave (SAW) has great potentials due to its high energy efficiency and effective integration on structural surfaces. However, anti-/de-icing processes activated by SAWs involve complex interfacial evolution and phase changes, and it is crucial to understand the nature of dynamic solid–liquid–vapor phase changes and ice nucleation, growth, and melting events under SAW agitation. In this study, we systematically investigated the accretion and removal of porous rime ice from structural surfaces activated by SAWs. We found that icing and de-icing processes are strongly linked with the dynamical interfacial phase and structure changes of rime ice under SAW activation and the acousto-thermally induced localized heating that facilitate the melting of ice crystals. Subsequently, interactions of SAWs with the formed thin water layer at the ice/structure interface result in significant streaming effects that lead to further damage and melting of ice, liquid pumping, jetting, or nebulization.

Surface Acoustic Waves Equip Materials with Active De‐Icing Functionality: Unraveled Glaze Ice De‐Icing Mechanisms and Application to Centimeter‐Scale Transparent Surfaces

“…[14] More recently, Yang et al researched the mitigation of rime ice formation and the melting of several hundred μm thick, porous layers of rime ice using SAW in piezoelectric films on aluminum plates measuring a few millimeters. [15] They attributed de-icing mainly to thermoacoustic effects caused by the SAW ice interaction and acoustic streaming inside the evolving liquid phase during melting. These studies [12,14,15] reported an efficient activation on thermally conductive materials, that is, metallic aluminum foils covered with a piezoelectric thin film.…”

“…[15] They attributed de-icing mainly to thermoacoustic effects caused by the SAW ice interaction and acoustic streaming inside the evolving liquid phase during melting. These studies [12,14,15] reported an efficient activation on thermally conductive materials, that is, metallic aluminum foils covered with a piezoelectric thin film. In a recent work carried out both in laboratory and icing wind tunnel conditions, we have also demonstrated energy-efficient de-icing and prevention of icing with decreased surface ice adhesion using high-frequency shear acoustic vibrations in larger bulk piezoelectric substrates.…”

“…[17] Refs. [12,14,15] have inferred some physics and understanding of the de-icing mechanism applicable to small ice volumes (in the order of microliters) and layers of porous rime ice. However, in these works, the activation of de-icing processes on surfaces (generally referred to as surface activation) was only performed on the IDTs and in their vicinity zones on substrate materials with good heat conductivity, creating effective de-icing areas that measure tens of SAW wavelengths (i.e., in the order of millimeters).…”

“…Analyzing this variable in a specifically designed experiment has allowed us to prove that IDT-associated Joule effects are irrelevant for de-icing on low-thermal conductive substrates, an issue difficult to address on other substrates, particularly if they are metallic. [12,14,15] Second, we demonstrate the de-icing capabilities for industrially relevant materials, that is, a commercially available optical grade fused silica substrate (f-silica or f-SiO 2 ) with dimensions of 30 mm x 15 mm x 0.5 mm, which is coated with a 5 μm piezoelectric highly-texturized ZnO film. This system demonstrates the feasibility of the methodology in an interesting application test for real-world scenarios, for example, in vision and optical sensor windows that are vulnerable to ice buildup.…”

Fundamentals of Monitoring Condensation and Frost/Ice Formation in Cold Environments Using Thin-Film Surface-Acoustic-Wave Technology

“…As seen from Table , ultrasonic and acoustic wave technologies are two promising candidates to monitor ice/frost formation in a cold environment, and they are commonly based on monitoring of the vibration frequencies with the capability of ice thickness measurement. ,, Another key advantage of these techniques is that they can also be used as active deicing or antiicing methods. For example, recent studies clearly show that, for ice mitigation, surface-acoustic-wave (SAW) devices can generate both acoustic wave vibrations and thermal effects on the device surface, , thus offering great potential for both antiicing and deicing with a reasonably high efficiency. − Therefore, it could be applied as one of the appropriate techniques for effectively tackling icing issues on structural surfaces. However, the conventionally used bulk piezoelectric ceramic-based ultrasonic or SAW devices have critical issues such as brittleness of the piezoelectric substrates (especially at high acoustic wave powers or large mechanical forces), rigidity, and noncompatibility with structural surfaces or microelectrics-based mass production technologies.…”