Ice Phenomena Research Articles

Long-Term Changes in the Thermal and Ice Regime of the Biebrza River (Northeastern Poland) in the Era of Global Warming

In the context of ongoing environmental changes, particularly against the backdrop of global warming, significant attention is being given to areas of exceptional natural value that, in many aspects, retain a pristine character. One such area is the Biebrza River in northeastern Poland, which, together with the wetlands in its basin, forms one of the most valuable ecosystems of its kind in Europe. This study analyses the changes in the thermal and ice regime for two hydrological stations, Sztabin and Burzyn, in the period from 1959 to 2023. It was found that the average annual water temperature in this period for the Biebrza River increased by 0.28 °C/decade, and in the case of ice phenomena, statistically significant changes for both stations showed a decline, with an acceleration of the ice cover disappearance by an average of 3 days/decade. These recorded changes should be considered unfavourable, as they will affect the transformation of both the biotic and abiotic characteristics of the river itself, as well as the natural elements associated with it.

Long-term variability of ice regime characteristics in river mouth areas of the western coast of the White Sea on the background of climatic changes

The paper presents results of the comprehensive study of the long-term variability of the main elements of the ice regime for the period 1955–2020 in mouth areas of the rivers Gridina, Kuzema, Pongoma, Kem, Shuya, Nizhny Vyg, Suma, Nyukhcha and Maloshuika flowing into the White Sea on its western coast (Republic of Karelia, Arkhangelsk region). The average daily air temperatureы in sites of the State observation network of Roshydromet – marine hydrometeorological coastal stations Gridino, Kem and Onega - were used as initial information for this work. Information about the main characteristics of the ice regime (times of coming of characteristic dates of ice phenomena) of the rivers was presented by data from nine hydrological posts. The mean values of characteristics of the ice regime (average statistical dates and durations of the ice regime phases) of the rivers under consideration (except those regulated by the cascade of hydroelectric power stations). were calculated. Statistical analysis of time series of the mean air temperatures obtained for the cold season on the western coast of the White Sea and the duration of periods with ice phenomena on the above rivers made possible to reveal two quasi-homogeneous periods with a turning point in 1990. This analysis shows that the temperature background in years 1991–2020 is significantly higher (by 1.4 °C) than the similar one in 1956–1990, and at the same time the average duration of ice phenomena decreased to almost two weeks (shorter by 11 days). The regression analysis allowed finding the presence of a statistically significant negative trend in the duration of ice phenomena for the whole period (1956–2020), which is −3.3 days/10 years. At the same time, the shortening of the duration of the periods with ice phenomena is due equally to both a shift in the time of the beginning of the stable ice formations towards later dates (1.6 days/10 years), and the earlier dates of the ice phenomena end (−1.7 days/10 years).

SiO2/polydopamine photothermal superhydrophobic coating with good anti-icing performance

The icing phenomenon has become a safety hazard for the normal operation of equipment. In this work, we report a strategy for simply obtaining photothermal anti-icing coatings by spraying acrylic resin, polydimethylsiloxane and polydopamine modified SiO2 particles on a steel plate substrate. The prepared icephobic AR/PDMS/SiO2@PDA composite coating not only has excellent superhydrophobicity (WCA = 162°). It also shows good anti- and de-icing performances. The superhydrophobic surface was able to delay freezing for 614 s at −20°C, and the ice adhesion of its surface was 54 kPa. In addition, PDA-modified SiO2 particles endow the coating with photothermal properties. Under the irradiation of simulated sunlight, the photothermal coating rapidly reached 61°C within 3 min, and the ice droplets completely melted in 155 s. Besides, it's able to withstand a wide range of chemical attacks and mechanical impacts. After 15 icing-de-icing cycles and 40 sandpaper abrasions cycles test, the prepared coatings can still maintain remarkable ice-removal performance, demonstrating excellent mechanical robustness and stability in harsh environments.

Engineering and research problems related to ice phenomena at the Gdańsk Water Node

Engineering and research problems related to ice phenomena at the Gdańsk Water Node

Role of Lake Morphometric and Environmental Drivers of Ice Cover Formation and Occurrence on Temperate Lakes: A Case Study from the Eastern Baltic Lakeland, Poland

The presence of ice cover on temperate lakes is a crucial factor in determining the functioning of these ecosystems. The isolation of water from atmospheric influences significantly alters physical, chemical, and biological processes, and the intensity of this impact depends on the duration of the ice cover. This study analyzed the basic parameters of ice cover on several dozen lakes in Northeastern Poland. The aim of this study is to investigate the influence of morphometric parameters, alongside environmental factors, on the variation of ice cover characteristics in lakes located within the Eastern Baltic Lakeland. Characterization of ice conditions in the analyzed lakes was based on basic statistics such as minimum and maximum values, mean, standard deviation, coefficients of variation, skewness, and kurtosis. Given that the dataset contains variables describing ice phenomena in the studied lakes and data describing location, morphometric parameters, and land cover directly adjacent to the lake (treated as independent variables), a method of Spearman’s rank correlations and constrained ordination method were decided upon. Despite the relatively small study area, significant variability was observed, with average differences as follows: 26 days for the onset of ice cover, 17 days for the end date, 15 cm for ice thickness, and a 30-day difference in the average duration of ice cover. Key factors included parameters such as lake volume, average depth, and land use (urbanized and agricultural areas). Understanding parameters such as the onset and end of ice cover is essential for lake ecosystems, both from an ecological and economic perspective. This knowledge is crucial for interpreting the behavior of living organisms, water quality, and economic considerations.

Superior anti-icing performance of a silicone-based slippery gel coating with a self-replenishing lubricant layer under airflow

Icing phenomena lead to energy consumption, mechanical failures, and potential human casualties. These issues often occur under dynamic airflow conditions. While superhydrophobic (SHPo) surfaces effectively delay ice formation under airflow, they cannot completely prevent it without external energy. This study proposes a long-chain entangled polydimethylsiloxane (LEP) gel coating infused with a lubricant, as an excellent anti-icing surface. The LEP gel has a self-regenerative, low-viscosity oil layer, and it shows remarkable droplet mobility, a very low contact angle hysteresis (CAH), and near-zero ice adhesion. X-ray microimaging shows that condensed droplets on the LEP gel move dynamically, while a bare silicone coating exhibits static behavior. This dynamic droplet behavior significantly delays droplet freezing and frost onset. The LEP gel’s anti-icing performance is assessed in a subsonic wind tunnel. Unlike control surfaces on which frost forms immediately, droplets condense on the gel and then slide off, reducing the frost-coverage rate. Notably, at a wind speed of 5.5 m/s, no frost is formed on the gel. The LEP gel’s superior anti-icing performance is attributed to synergistic effects of the lubricant layer and extremely low CAH. These results show that lubricant-infused slippery gel coatings could prevent icing in airflow environments.

Fabrication of SiO2/PDMS/EP superhydrophobic coating for anti-icing

In low-temperature environments, the condensation and icing phenomena of water molecules on material surfaces may adversely affect the functionality and durability of various products, so it is critical to improve the anti-icing properties of material surfaces. In this study, the anti-icing mechanism of superhydrophobic coatings was analyzed based on the surface wettability theory, and SiO2/PDMS/EP superhydrophobic coating was fabricated by the spraying method. The surface wettability, surface micro-morphology, and surface chemical composition of the coating was characterized, and the stability of the coating as well as the anti-icing properties were investigated. The results show that the SiO2/PDMS/EP superhydrophobic coating sprayed on the Al-based surface has a contact angle of 163.3° and a sliding angle of 4°, and the coating maintains excellent superhydrophobicity at a low temperature of -15°. This coating can significantly delay the freezing time and temperature of droplets on its surface, reduce the shear force and natural deicing time required to remove surface ice, and exhibit excellent anti-icing performance. The excellent anti-icing durability of the coating was demonstrated by the icing-deicing cycle experiment. Subsequently, the anti-frosting performance was further investigated, and the results showed that it effectively slowed down the speed of frost formation. Therefore, the superhydrophobic coating fabricated in this study is suitable for a wide range of working conditions and has potential practicality. It also provides experimental guidance for the application of anti-icing coatings on Al surfaces.

Investigating Shear Stress of Ice Accumulated on Surfaces with Various Roughnesses: Effects of a Quasi-Water Layer.

The investigation of the anti-icing/deicing is essential because the icing phenomenon deteriorates the natural environment and various projects. By conducting molecular dynamics simulation, this work analyzes the effect of the quasi-water layer on the ice shear stress over smooth and rough surfaces, along with the underlying physics of the quasi-water layer. The results indicate that the thickness of the quasi-water layer monotonically increases with temperature, resulting in a monotonic decrease in the ice shear stress on the smooth surface. Due to the joint effects of the smooth surface wettability and the quasi-water layer, the ice shear stress increases and then decreases to almost a constant value when the surface changes from a hydrophobic to a hydrophilic one. For rough surfaces with stripe nanostructures, when the width of the bump for one case equals the depression for the other case, the variations of shear stress with height for these two cases are almost the same. The rough surface is effective in reducing the ice shear stress compared to the smooth surface due to the thickening of the quasi-water layer. Each molecule in the quasi-water layer and its four nearest neighboring molecules gradually form a tetrahedral ice-like structure along the direction away from the surface. The radial distribution function also shows that the quasi-water layer resembles the liquid water rather than the ice structure. These findings shed light on developing anti-icing and deicing techniques.

An analytical model for ice accretion on the engine strut surface

To predict flight icing more widely and practically, an ice accretion numerical framework that incorporates both the water droplet splash and the ice crystal sticking is developed. By proposing a deformation hypothesis, we deduce the modified energy conservation expression and the force balance relation for water droplet impingement. Subsequently, a new threshold determination and the probabilities for the droplet splash and ice crystal sticking are obtained, which are applicative across a wide range of Weber number after the validation. Through the interface tracking for a single droplet with the volume of fluid method, the droplet impingement dynamics are further explored, and the results of interaction with the wall serve the boundary treatments of droplet impingement in the discrete phase model. Additionally, the probability statistics method is employed to determine the parameters of the secondary droplets. Through the dynamic mesh technique, the retentive water droplets and the collected ice crystals are transformed into the accumulated ice in real time to update the ice accretion on the strut surface. Results demonstrate that the diameter, velocity, and content of droplets or crystals play significant roles in the impingement and the icing phenomena. Based on our numerical model, the predictions show that the ice accretion on the engine strut is influenced by flight parameters and environmental conditions, providing crucial guidance for the icing protection processes.

Non-destructive evaluation method for track slabs damaged by impact of ice blocks detached from high-speed trains

In winter snowy or rainy weather, the phenomenon of icing under rolling stock during high-speed operation is significantly severe, posing a potential risk of detachment and impact on track structures due to the presence of ice blocks with substantial mass and velocity. Therefore, it is crucial to develop an efficient method for characterizing and evaluating this impact damage in order to assess the service life of the track. To address this issue, the indoor ice impact tests were conducted on track slab models, and a comprehensive analysis was performed on non-destructive testing data before and after the impact test, including 3D surface morphology assessment, surface hardness and wave velocity measurements. Additionally, in order to verify the effectiveness of the nondestructive testing method, the frozen-thawed and not frozen-thawed track slab models were tested and their results were compared. The experimental results revealed that when impacted by ice blocks at a velocity of 100 m/s, small dimples formed on the surface of track slab models with the maximum depth measured at 0.0694 mm. There was a maximum increase rate in surface hardness amounting to 11.61%, and a maximum decrease rate in wave velocity measuring at 6.52%. Furthermore, the impact damage of the two models has been evaluated, the not frozen-thawed track slab model exhibited minor damage after impact, whereas the frozen-thawed track slab model demonstrated moderate damage in the contact region and minor damage outside of that region. The proposed non-destructive testing method effectively enables assessing the impact damage inflicted upon slab models while providing valuable insights for maintenance and repair strategies related to track slabs.

Role of Molecular Water Layer State on Freezing Front Propagation Rate and Mode Studied with Thermal Imaging.

In this work, we study the relationship between the molecular water layer (MWL) and frost freezing onset and propagation. The progression of frost has been reported to be governed by various localized icing phenomena, including interdroplet ice bridging, dry zones, and frost halos. Reports studying the state of water on surfaces have revealed the presence of a thin nanometer water layer on a range of surfaces. Regardless of further investigations that show environmental humidity, temperature, and surface energy to affect the thickness of the MWL on surfaces, the influence of the MWL on frost nucleation and propagation has not yet been previously addressed in the literature. To study the effect of the MWL on surface freezing events, a range of surface-functionalized glass substrates were prepared. In situ monitoring of freezing events with thermal imaging allowed studying the effect of surface chemistry and environmental relative humidity (RH) on the thickness and continuity of the MWL. We argue that the observed icing nucleation and propagation kinetics are directly related to the presence and continuity of the MWL, which can be manipulated by controlling the environmental humidity and surface chemistry.

Environmental effects of river ice, The Saint John (Wolastoq) River, New Brunswick, Canada

ABSTRACT The Saint John (Wolastoq) River (SJR) is a major international river flowing through the State of Maine, USA, and the Province of New Brunswick, Canada. In terms of river length and basin area, it is one of the largest rivers on the eastern seaboard of North America south of the St. Lawrence River system. Subject to seasonal ice cover, ice conditions vary along the SJR due to natural differences in climate and terrain, and due to anthropogenetic changes, such as the construction of dams. Ice formation, growth, and breakup along the SJR affects its hydraulic and ecological regimes and leads to the potential for ice jamming that has caused severe flooding and ice runs. Ice affects river erosion, flooding, ecology, water quality, and recreational uses of the SJR. An overview of typical winter climate and ice season characteristics along the SJR from Dickey, Maine, USA to Saint John, New Brunswick, and some of its environmental consequences are summarized in this review paper. Ice processes and phenomena that occur along the SJR occur along other northern rivers, and can cause similar environmental concerns and consequences that should not be ignored in river engineering and basin management.

The icing characteristic of stage 35 compressor blades and its impact on aerodynamic performance

The icing problem in aeroengine is prominent, posing a serious threat to flight safety. There are some limitations in current icing research for aeroengine, which limits the understanding of icing mechanism and potential impact. In this study, a 3D numerical method for air-water two phase flow in rotational situation is developed, and the icing thermodynamic model under the aeroengine environment is established. The study focuses on the icing characteristic of stage 35 compressor under different conditions, as well as the effect of icing shapes on aerodynamic performance. The results indicate that the icing distribution of stage 35 rotor shows obvious 3D characteristic, and the ice amount has an increasing trend with the rise of blade span. Due to the nonuniform distribution of temperature on rotor surface, the rime ice begins to transform into glaze ice from the top of blade when the temperature increases. The quantitative result also finds that the icing has a serious impact on compressor performance, in terms of mass flow, pressure ratio and isentropic efficiency. The flow obstruction caused by the blunt structure at the leading edge is the main reason affecting performance. The research indicates that the icing phenomenon in aeroengine is more complex than that on airfoil, and its threat to performance cannot be ignored in engineering.

An experimental study on the effect of CO2 laser powers on melting characteristics of clear ice − part I: Horizontal irradiation

Icing phenomenon widely exists in traffic and industrial fields, and causes a lot of safety accidents. Laser deicing technology is a typical high-efficiency and non-contact deicing method. To accurately predict and control the laser-induced ice melting process, an experimental study on melting characteristics of clear ice under horizontal CO2 laser irradiation and natural convection is carried out, with the laser power varied at a range of 20 ∼ 60 W. As resulted, in the first 27 s of the melting process, the axial melting rate is around 1.2 mm/s at each power. After 27 s, the laser power effect on the melting rate is obviously different, and the maximum melting rate reaches 5.41 mm/s at 50 W. The higher the laser power, the more the ice melts, and the easier the path of melting ice deflects. At 20 W and 50 W, the maximum angles of melting height are 1.14° and 4.18°, respectively. The laser power effect on the maximum melting height is obvious. At 20 W and 50 W, the peaks of maximum melting height are 12.84 mm and 22.59 mm, respectively. The higher the laser power, the larger the volume melting rate of ice, but the greater the energy loss, and it directly influences the energy efficiency. The ice-melting energy efficiency decreases with the increase of laser power. For laser at 20 W and 60 W, the maximum energy efficiency are 81.5 % and 54.6 %, respectively. This study is meaningful for the optimization of laser deicing technology.

Numerical Study on Prediction of Icing Phenomena in Fresh Air and Blow-by Gas Mixing Region of Diesel Engine under High Velocity of Intake Air Condition

The icing of an intake pipe that might happen in an actual vehicle was numerically predicted in this study. For various operating conditions, the amount of icing was estimated, and the variables influencing the amount of icing were identified. We compared the factors that affected icing: relative humidity, air temperature, and inlet velocity. Seven RPM and load conditions, an intake temperature range of 253–268 K, and a relative humidity range of 65–85% were used for the case studies. To verify the model accuracy, wind tunnel test results from chassis dynometer tests were compared to the data from simulations. The flow analysis was performed using the numerical analytical tool ANSYS Fluent (2019 R1), while the amount of condensed water and icing was predicted using FENSAP-ICE, a program that analyzes and predicts icing phenomena under mechanical systems. The ambient temperature, relative humidity, and inlet air velocity had the biggest effects on the icing rate. The total amount of icing increased for similar BB and input air velocities. When the input air and BB velocities are the same, the variables influencing icing are the ambient temperature and relative humidity. The amount of ice was less affected by outside temperature and relative humidity when the rpm was high, and the inlet air velocity also had an impact.

Regional features of glaze ice events frequency in the north of the European territory of Russia in the current changing climate

Recently, the interest in society in observing and forecasting dangerous meteorological phenomena in the cold period of the year has noticeably grown. In this work, we study the phenomenon of glaze ice in the north of the European territory of Russia in the North-Western Federal District. Here glaze ice (icing) is less frequent than other forms of ice accretion, but its characteristics most often exceed the criteria of dangerous meteorological phenomena. It is a great danger for various areas of the economy, ship navigation, causing an increase in traumatism of the population and damage to infrastructure. In accordance with the aim of the work, the spatial and temporal variability of the frequency of glaze ice accretion on the territory of the North-Western Federal District in the period 1986–2022 is investigated. The results are obtained on the basis of instrumental observations of meteorological stations. Using statistical analysis, the features of mean yearly frequency at each meteorological station were studied. To assess the direction of annual changes in the glaze ice frequency, the linear trend coefficient was calculated for each meteorological station. The least squares method was used for this purpose. It is shown that the maximum number of days with glaze ice occurs in the central part of the North-Western Federal District. This can be attributed to the more frequent movement of Atlantic and southern cyclones to high latitudes and their precipitation, especially at the atmospheric fronts and in the warm sectors of the cyclones, at air temperatures near zero and below. What makes the spatial distribution of glaze ice frequency even more uneven is the presence of uplands in the European territory of Russia. More precipitation falls on their windward slopes, and the temperature decreases with altitude. The findings show that in recent decades there has been an increase in the frequency of the glaze ice phenomenon in the region. At the same time, the interannual variability remains relatively constant. Taking into account the positive trend in the number of glaze ice events and increasing air temperature and precipitation, it is necessary to develop measures to deal with this hazardous phenomenon and minimize damage from it.

The range of ice thrusts and ice piles as reflected by ice scars on trees growing on the shores of coastal lagoons: The case of the Szczecin Lagoon

We studied the phenomena associated with the thrusting of ice onto the shore of the Szczecin Lagoon based on the occurrence of tree ice scars. The measurements concerned mostly the maximum height, length and width of ice scars on trees, and the distance of these trees from the shore in the period 2017–2022. It was observed that sheets of ice advanced up to 64 m inland, and piled to form hummocks reaching up to 4.3 m above the water level. These maximum values occurred mostly on eastern shores, which is where the highest numbers of damaged and broken trees were observed. This should be associated with the strongest and most frequently occurring wind blowing from the western direction in the winter-spring period. To the contrary, the lowest number of damaged trees were observed on the western shore. This is due not only to the lower frequency of wind blowing from the east, and the associated cooling (Ta < 0°C) and ice cover stabilization, but also due to the presence of extensive reed belts. Our results enable an indirect insight into the ice phenomena dynamics, especially in areas lacking systematic ice observations. Similar conclusions may be extended for all the sheltered basins as lakes or lagoons.

An experimental study on the effect of CO2 laser powers on melting characteristics of clear ice – Part II: Vertical irradiation

Icing phenomenon widely exists and plays negative effects in aviation and electricity fields. Laser deicing technology is a typical non-contact and high-efficiency deicing method. To accurately predict and control the laser-induced ice melting process, an experimental study on melting characteristics of clear ice under vertical CO2-laser irradiation and natural convection is carried out, with the laser power varied at a range of 20–60 W. As resulted, the axial melting rate tends to increase and then decrease with the increase of laser power. The maximum of average and instantaneous axial melting rate at 40 W are 5.85 mm/s and 13.95 mm/s, respectively. The higher the laser power, the larger the peaks of maximum melting length. At 20 W and 60 W, the peaks of maximum melting length are 10.51 mm and 12.19 mm, respectively. There is little correlation between the deflection of angle and laser power. At 30 W and 50 W, the maximum angles of melting length are 0.77° and 2.52°, respectively. When the melting depth is smaller than 81.5 mm, the maximum energy efficiency at 20 W is 64.8 %, while when it is greater than 81.5 mm, the maximum energy efficiency at 60 W is 63.6 %. Results of this study are meaningful for the optimization of laser deicing technology.

Characteristics and mechanism of droplet bouncing on cross-ridge superhydrophobic surfaces: Simulations and theory

The behaviors of droplets impinging on superhydrophobic surfaces have received much attention from industry and academia due to potential applications such as anti-icing, spray cooling, and self-cleaning. Previous studies have shown that the superhydrophobic surfaces can significantly reduce contact time and thus effectively suppress surface icing and condensation phenomena. In this paper, the bouncing behaviors of droplets on superhydrophobic surfaces decorated with cross ridges were investigated using numerical simulations and theoretical analysis. The effect of cross-ridge structures with different pinch angles and droplets with different Weber numbers on droplet bouncing behaviors was investigated using the volume-of-fluid method. The results showed that the solid–liquid contact time was shortest when the angle between the two ridges was 75°. Compared to droplet bouncing on a smooth surface, the contact time was reduced by up to 30% for complete bouncing behaviors and up to 68% for broken bouncing behaviors. As the angle decreased, the ratio of spreading areas between child droplet sizes increased exponentially. The momentum of the smaller child droplet decreased until it was no longer generated. A theoretical analysis based on energy conservation was also performed. A theoretical equation was proposed to predict the maximum spreading coefficient. The maximum error was less than 10% for the experimental and numerical results compared to the predicted results.

Warming Climate-Induced Changes in Lithuanian River Ice Phenology

Due to rising surface air temperatures, river ice is shrinking dramatically in the Northern Hemisphere. Ice cover during the cold season causes fundamental changes in river ecosystems and has important implications for nearby communities and industries. Changes caused by climate warming, therefore, affect the sustainability of key resources, livelihoods, and traditional practices. Thus far, too little attention has been paid to research into the phenomenon of river ice in the Baltic States. Since the observational data of the last sixty years are currently available, we took advantage of the unique opportunity to assess ice regime changes in the gauged rivers by comparing two climatological standard normals. By applying statistical methods (Mann–Kendall, Pettitt, SNHT, Buishand, von Neumann, and Wilcoxon rank sum tests), this study determined drastic changes in ice phenology parameters (freeze-up date, ice break-up date, and ice cover duration) of Lithuanian rivers in the last thirty-year period. The dependence of the selected parameters on local climatic factors and large-scale atmospheric circulation patterns was identified. It was established that the sum of negative air temperatures, as well as the North Atlantic Oscillation, East Atlantic, and Arctic Oscillation indices, have the greatest influence on the ice regime of Lithuanian rivers.