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Superhydrophobic coatings can be a suitable solution for protecting vulnerable electrical infrastructures in regions with severe meteorological conditions. Regenerative superhydrophobicity, the ability to regain superhydrophobicity after being compromised or degraded, could address the issue of the low durability of these coatings. In this study, we fabricated a superhydrophobic coating comprising hydrophobic aerogel microparticles and polydimethylsiloxane (PDMS)-modified silica nanoparticles within a PDMS matrix containing trifluoropropyl POSS (F-POSS) and XIAMETER PMX-series silicone oil as superhydrophobicity-regenerating agents. The fabricated coating exhibited a static contact angle of 169.5° and a contact angle hysteresis of 6°. This coating was capable of regaining its superhydrophobicity after various pH immersion and plasma deterioration tests. The developed coating demonstrated ice adhesion as low as 71.2 kPa, which remained relatively unchanged even after several icing/de-icing cycles. Furthermore, the coating exhibited a higher flashover voltage than the reference samples and maintained a minimal drop in flashover voltage after consecutive testing cycles. Given this performance, this developed coating can be an ideal choice for enhancing the lifespan of electrical insulators.

This study investigates the effects of microcylindrical pillar geometry on surface wettability and ice nucleation time. The cylindrical micropillars were designed and then fabricated on silicone rubber surfaces by micromachining to create a template, followed by direct replication using a compression molding method. This approach offers an efficient, nontoxic, and low-cost means of producing micro-nanoscale roughness on surfaces. We tested the wetting (i.e., contact angle and contact angle hysteresis) and anti-icing (i.e., ice nucleation time) properties of the patterned silicone rubber surfaces having different combinations of pillar diameter and interpillar spacing. According to our experimental results for a limited range of pillar diameters (80 and 110 ) and center to center spacing (pitch; 125–300 ), decreasing the diameter and increasing the space of micro-cylindrical pillars may result in the Cassie wetting until a threshold value. Beyond this pillar diameter/pitch threshold, Wenzel wetting occurred. Surfaces characterized by pillars of different diameter and pitch also increased the freezing delay by reducing the area of ice–substrate contact and the heat transfer between the water droplet and the surface. We demonstrate that the properties of superhydrophobic and anti-icing surfaces can be controlled by altering the geometry of micropillars across the surface.

The fluids studied in this section are EG106 SAE Type IV and Polar Guard Advance Type IV. EG 106 is an ethylene glycol-based product, and PG is a propylene glycol-based product. For each test, 16.2 g of the product was placed on a small aluminum plate with a thickness of about 1.6 mm. The tests were conducted at-5 C, and the cold chamber ventilation was set at 60. During this test, several snow deposits of the same quantity were applied to each product every 2 minutes

Poor braking performance on runways during winter is one of the most significant factors causing runway excursions. The International Civil Aviation Organization (ICAO) proposed a standardized method, named the Global Reporting Format (GRF), to establish runway surface conditions based on human observers. The GRF includes the description of most winter conditions. This work aimed at reproducing the GRF winter conditions in the laboratory, and to monitor the effect of the surface conditions, both without surface treatment and with surface treatment using liquid runway de-icing products (RDP) in both de-icing and anti-icing modes, using the British Pendulum Tester (BPT). The reproduction of the GRF winter conditions was possible in the laboratory since the BPT results correlated well with the GRF ratings. The worst conditions retained snow on ice. Wet conditions obtained with water and RDPs (potassium formate KFO, potassium acetate KAC and hybrid glycol-KAC HYB) behave similarly, indicating that RDPs alone on a runway for prevention are not any more dangerous than just water. The range from wet to dry, equivalent to a British Pendulum Number (BPN) from ~40 to ~50, was considered as good conditions on the runway. All the RDPs tested in the study improved the BPN from untreated conditions. In most of the conditions, the RDPs improved the BPN to values in the range of favorable conditions. KFO and KAC reacted almost in the same way for each condition. However, the HYB was better in conditions with ice. The obtained results demonstrated that simulated laboratory winter conditions could be used to determine the efficiency of RDPs in both de-icing and anti-icing modes.

The usage of De-Icing and Anti-Icing fluids is the most common method recognized to protect aircraft on the ground from freezing and frozen contaminants. The snow endurance times, which means the duration that a fluid can protect the vehicle from snow accumulations, is currently determined outdoor under natural conditions. To replace this expensive and very impractical method, the Anti-Icing Materials International Laboratory developed snow machine was used to perform a comparative study. In this first study, three commercial fluids were tested at various snow intensity rates under artificial snow generated with the snow machine in a cold chamber to validate the testing procedure and investigate the way forward. The results obtained were then positively compared to natural snow endurance times. They were also compared with natural snow regression curves, showing similar trends. This study demonstrated the great potential of this method showing the necessity of pursuing this investigation.