Yujin Yao , Wenchang Liu , Huaxin Chen , Yunhao Jiao , Teng Yuan , Jiayu Wu , Can Guo , Yongchang Wu
{"title":"Investigate the adhesion behavior and mechanisms of salty ice on bitumen surface based on the ice heterogeneous nucleation kinetics and quasi-liquid layer theory","authors":"Yujin Yao , Wenchang Liu , Huaxin Chen , Yunhao Jiao , Teng Yuan , Jiayu Wu , Can Guo , Yongchang Wu","doi":"10.1016/j.coldregions.2024.104378","DOIUrl":"10.1016/j.coldregions.2024.104378","url":null,"abstract":"<div><div>Understanding the freezing and adhesion properties of de-icing salt solutions is crucial for optimizing de-icing strategies in infrastructure and minimizing damage to the environment and road materials from de-icing salts. This work employed a customized ice-adhesion testing system to investigate the evolution of ice-adhesion strength (IAS) of NaCl and NaCH₃COO salts on bitumen surfaces under different concentrations and temperatures. The icing phase transition process and thermodynamic properties of the salt solution were analyzed using multi-channel temperature setting and differential scanning calorimetry (DSC). Moreover, the adhesive mechanisms of salty ice were elucidated based on heterogeneous nucleation kinetics and quasi-liquid layer (QLL) theory. The results show that even a 0.5 wt% salt solution can lower the IAS to approximately 40–50 % of the value observed with pure water. The concentration of salt solution required to achieve adhesive failure is temperature-dependent. Additionally, the latent heat of fusion (<em>h</em><sub><em>f</em></sub>) of NaCl solutions at concentrations from 0.5 to 2.5 wt% sequentially decreased by 45.3 J/g, 63.1 J/g, 79.9 J/g, 90.0 J/g, and 117.6 J/g compared to pure water. The freezing temperature (<em>T</em><sub><em>F</em></sub>) of 2.5 wt% NaCH₃COO and NaCl solutions dropped by 1.3 °C and 1.6 °C, respectively. Based on the ice nucleation kinetics, lowering the <em>T</em><sub><em>F</em></sub> and <em>h</em><sub><em>f</em></sub> leads to an increase in the nucleation energy barrier (ΔG*), with IAS showing a logarithmic correlation with ΔG*. Furthermore, the QLL transitions from droplets to a thin film as salinity increases, further reducing the contact area and IAS. This work offers novel insights into the freezing progress and adhesion mechanisms of salty ice, aiming to reduce maintenance costs and environmental damage from de-icing salts.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"231 ","pages":"Article 104378"},"PeriodicalIF":3.8,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jan Wittig , Georgios Tzortzinis , Niels Modler , Maria Lißner , Angelos Filippatos
{"title":"Vibration-based ice monitoring of composite blades using artificial neural networks under different icing conditions","authors":"Jan Wittig , Georgios Tzortzinis , Niels Modler , Maria Lißner , Angelos Filippatos","doi":"10.1016/j.coldregions.2024.104379","DOIUrl":"10.1016/j.coldregions.2024.104379","url":null,"abstract":"<div><div>Cold climates pose significant challenges for wind turbines, primarily due to icing that influence electrical energy production. Precise methods are needed to identify and predict ice distribution on blades, enabling enhanced prediction of ice accumulation based on the blade's frequency response. This study uses glass fiber reinforced plastic composite rotor blades equipped with actuators and accelerometers to measure, with a total of <span><math><mn>1700</mn></math></span> measurements, the response of the blade subjected to icing. Small-scale icing experiments are conducted inside a climate chamber at temperatures ranging from <span><math><mo>−</mo><msup><mn>10</mn><mo>∘</mo></msup><mi>C</mi></math></span> to <span><math><mo>−</mo><msup><mn>20</mn><mo>∘</mo></msup><mi>C</mi></math></span> with seven ice distribution profiles on the blades. The gathered data is analyzed for the effects of icing on the frequency response of the blades. Optimized artificial neural networks, using fully connected layers and convolutional layers, are proposed to predict the accumulated ice thickness on rotor blades based on the frequency response, with weighted mean absolute percentage errors of 5.1 % and 5.8 %, respectively, and to predict ice volume and ice mass with errors of 5.7 % and 4.9 %, respectively. Overall, this study investigates the effect of icing on the frequency response of composite blades with regard to ice mass and ice location, and proposes a high-performance data-driven method for ice detection and monitoring during operation.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"231 ","pages":"Article 104379"},"PeriodicalIF":3.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yafang Guo , Wansheng Pei , Mingyi Zhang , Deren Liu , Ruiqiang Bai , Yanqiao Zhou , Guanji Li
{"title":"Numerical study on cooling performance of the L-shaped crushed-rock embankment in permafrost regions","authors":"Yafang Guo , Wansheng Pei , Mingyi Zhang , Deren Liu , Ruiqiang Bai , Yanqiao Zhou , Guanji Li","doi":"10.1016/j.coldregions.2024.104380","DOIUrl":"10.1016/j.coldregions.2024.104380","url":null,"abstract":"<div><div>In permafrost regions, crushed-rock embankments are favored for their environmental compatibility and thermal efficiency. This study introduces the innovative L-shaped crushed-rock embankment (LCRE), which features a crushed-rock layer exclusively at the base and on the sunny slope, providing a cost-effective alternative to the conventional U-shaped design. Using numerical methods, we assessed the cooling performance of the LCRE compared to other crushed-rock embankments, focusing on the impact of its geometric parameters. The findings indicate that the overall cooling performance of the LCRE is situated between that of the crushed-rock interlayer embankment and the U-shaped crushed-rock embankment, and its ability to mitigate the shady and sunny slope effect is superior to that of the U-shaped crushed-rock embankment. Additionally, our analysis reveals that increasing the horizontal width of the revetment to enhance cooling is not a cost-effective approach. The LCREs is more suitable for higher embankments than U-shaped counterparts. Despite the LCRE's advantageous thermal performance and cost benefits, its asymmetric load distribution could lead to exacerbated differential settlement, highlighting the need for further research. This study offers pivotal insights into the design and development of innovative crushed-rock embankments in permafrost regions.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104380"},"PeriodicalIF":3.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142756598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Molly E. Tedesche, Aaron C. Meyer, Sergey N. Vecherin, Tate G. Meehan
{"title":"How strong is Snow? Spatial correlations of snowpack load bearing capacity and micromechanics from NASA SnowEx SnowMicroPen Data at Grand Mesa, Colorado","authors":"Molly E. Tedesche, Aaron C. Meyer, Sergey N. Vecherin, Tate G. Meehan","doi":"10.1016/j.coldregions.2024.104369","DOIUrl":"10.1016/j.coldregions.2024.104369","url":null,"abstract":"<div><div>The mechanical and structural properties of a snowpack, at both the micro- and macro-scales, are critical to understanding how snow cover architecture evolves over each winter. Snow load bearing capacity across a landscape is extremely spatially variable, yet fundamentally important for an array of applications. Such applications include winter vehicle mobility and modeling wildlife movements, among others. In this study, we derive snowpack microstructural and micromechanical properties across Grand Mesa, Colorado using SnowMicroPenetrometer (SMP) penetration force datasets from the NASA SnowEx 2017 and 2020 field campaigns. For the first time, raw SMP data from the SnowEx campaigns are processed and analyzed to derive snow cover microparameters, using empirical and physical methods involving microstructural dimensions of the snow crystal matrix. We propose a newly created equation for an SMP-derived snow load bearing capacity micromechanical parameter. We also refine one technique for identifying top and bottom boundaries of snow profiles in SMP raw data.</div><div>The final component of this study involved an analysis of SMP-derived snow microparameter spatial variability across Grand Mesa, Colorado. Results of the statistical analyses for the two different years revealed consistency in spatial relationships. Microparameters that exhibited non-zero cross correlations included snow density, compression strength, load bearing capacity, and microstructural deflection during snow grain bond rupture.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"231 ","pages":"Article 104369"},"PeriodicalIF":3.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Håvard B. Toft , Kristoffer Karlsen , Markus Landrø , Andrea Mannberg , Jordy Hendrikx , Audun Hetland
{"title":"Who skis where, when? – A method to enumerate backcountry usage","authors":"Håvard B. Toft , Kristoffer Karlsen , Markus Landrø , Andrea Mannberg , Jordy Hendrikx , Audun Hetland","doi":"10.1016/j.coldregions.2024.104370","DOIUrl":"10.1016/j.coldregions.2024.104370","url":null,"abstract":"<div><div>Backcountry skiers, travelling in avalanche terrain, account for a large proportion of avalanche fatalities worldwide. Despite this, the exact count of the number of recreationists exposed to avalanches (also known as the background information), is poorly documented in most countries. Without detailed background information on temporal and spatial backcountry usage, making well-reasoned decisions from fatality statistics is impossible. This study developed a methodology to enumerate a large proportion of backcountry usage from a 2589 km<sup>2</sup> study area in Tromsø, Northern Norway. We use an extensive network of specially adapted beacon checkers – small, waterproof devices that detect and count signals from avalanche transceivers. Over two seasons, from December to May from 2021 to 2023, we recorded 56,760 individual trips. Our findings indicate that most (60.0 %) backcountry trips begin between 07:00 and 12:00, with noticeable activity in the afternoon as well. Saturdays and Sundays see the highest daily activity rates, comprising 40.1 % of total weekly traffic, while weekdays, though less busy per day, account for the remaining 59.9 %. The peak season for winter backcountry skiing is during March and April (when counts from the period December to May are considered), accounting for 56.3 % of all traffic. This monthly usage aligns with avalanche incident data, where 55.8 % of incidents occur during the same two months. Our study demonstrates the use of our methodology and advances the understanding of temporal trends from winter backcountry skiing, quantifying the movement characteristics of backcountry skiers in Tromsø, Norway.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104370"},"PeriodicalIF":3.8,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Unified hardening (UH) model for saturated frozen soils","authors":"Kesong Tang, Yangping Yao","doi":"10.1016/j.coldregions.2024.104371","DOIUrl":"10.1016/j.coldregions.2024.104371","url":null,"abstract":"<div><div>The mechanical behavior of frozen soils is highly sensitive to temperature variations due to their complex micro-mechanisms. In regions with seasonal freeze-thaw cycles, the transition of soils between frozen and unfrozen states is significantly influencing their mechanical properties. This study synthesizes existing theories and data to categorize the effects of subzero temperatures on the properties of frozen soils. By introducing temperature and unfrozen water saturation, the phase change component of void ratio—decoupled from stress—is distinguished from actual voids, enabling the definition of the equivalent void ratio. Nonlinear relationships between temperature and other mechanical properties including elastoplastic deformation, cryogenic cohesion and ice segregation are established. Through the derivation of a loading-temperature yield equation, an elastoplastic constitutive model within a dual stress-variable framework of effective stress and temperature is established. This model captures key aspects of the behavior of frozen soils, including strength weakening due to ice segregation and temperature-induced strength changes. Applicable to conditions at or below the pore water melting point, the model's predictions align well with experimental observations.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104371"},"PeriodicalIF":3.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mingchen Chi , Yuyao Hu , Xingliang Jiang , Zongyuan Liu , Yue Gao , Mengyang Zhao , Wentao Jia
{"title":"Influence mechanism of AC electric field on rime ice accretion on the insulator and its experimental verification in the natural environment","authors":"Mingchen Chi , Yuyao Hu , Xingliang Jiang , Zongyuan Liu , Yue Gao , Mengyang Zhao , Wentao Jia","doi":"10.1016/j.coldregions.2024.104367","DOIUrl":"10.1016/j.coldregions.2024.104367","url":null,"abstract":"<div><div>Insulator icing can easily trigger flashover trips in heavily ice-covered areas, and analyzing the formation mechanism of ice accumulation on the insulator is essential for predicting its flashover development. To accurately dissect the process of insulator icing, a coupled mathematical model of the flow field and electric field, as well as a droplet motion model were elaborated in this paper based on the principles of fluid mechanics and electromagnetic field. Subsequently, the characteristics of droplet motion deviation and its physical collision process with an insulator surface under AC electric field were investigated. The results demonstrate that the charged droplets tend to oscillate along the electric field lines in AC electric field, and the amplitude of the oscillation increases with the applied voltage increasing. Moreover, the number of droplets captured by the insulator rises with the increase of voltage, wind speed, and median volume diameter of the droplet. Combined with the simulation and natural icing experiments, it is observed that ice branches grow in the direction of electric field force, and as the voltage rises, ice branches gradually spread from the edge of the shed to its surface, increasing surface roughness. The density of ice exhibits an inverted U-shaped relationship as the electric field strength increases. Ice mass and ice length present nonlinear growth with an increase in icing time. Furthermore, compared with that without energization, the icing amount and icing length increase by more than 13 % under AC voltage of 40 kV.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104367"},"PeriodicalIF":3.8,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hui Zhang , Yugui Yang , Chengzheng Cai , Shanshan Hou , Chenxiang Li
{"title":"The theoretical freezing model of sandstone considering the statistical arrangement of pore structure","authors":"Hui Zhang , Yugui Yang , Chengzheng Cai , Shanshan Hou , Chenxiang Li","doi":"10.1016/j.coldregions.2024.104366","DOIUrl":"10.1016/j.coldregions.2024.104366","url":null,"abstract":"<div><div>It is of great significance to understand the evolution law of unfrozen water content in frozen rocks to maintain the stability of geotechnical engineering in cold regions. Due to the different particle sizes and shapes, coupled with the diversity of cements, the internal pore structures of rocks are complex and diverse. In this study, a theoretical model for freezing point of sandstone is proposed based on the characteristics of microscopic pore structures. The characteristic of freezing point is analyzed by considering the mineral particle arrangement. A statistical theoretical model of unfrozen water in sandstone is established according to the random arrangement of mineral particles. The influence of the stacking angle of mineral particles following the normal distribution on unfrozen water content is analyzed. Finally, the NMR freezing process analysis for sandstones was carried out. The results show that the statistical theoretical model of unfrozen water fits the experimental results well. The effect of the average value of stacking angle on unfrozen water content is mainly due to the change of pore size, which leads to the change of pore water content. The standard deviation of stacking angle determines the residual water content.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104366"},"PeriodicalIF":3.8,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Furong Liu , Wei Ma , Zhiwei Zhou , Zhi Wen , Mingde Shen , Ruiqiang Bai
{"title":"Experimental investigation of cyclic responses of frozen soil under principal stress rotation induced by wave loads","authors":"Furong Liu , Wei Ma , Zhiwei Zhou , Zhi Wen , Mingde Shen , Ruiqiang Bai","doi":"10.1016/j.coldregions.2024.104368","DOIUrl":"10.1016/j.coldregions.2024.104368","url":null,"abstract":"<div><div>Under the effect of wave loads, continuous and cyclic principal stress rotation (PSR) occurs, with constant principal stress values in foundation soil units. The stability of coastal engineering structures in permafrost regions is inevitably subjected to the persistent impact of wave loads, which poses a significant challenge to their durability. Consequently, a series of experimental studies were carried out using a frozen hollow cylinder apparatus (FHCA) to investigate the influence of crucial three-dimensional stress state parameters, including the coefficient of intermediate principal stress (<em>b</em>), mean principal stress (<em>p</em>), and principal stress rotation radius (<em>R</em>), on the deformation characteristics and dynamic property evolution of frozen soils. The results indicated that under continuous principal stress rotation, the mean principal stress <em>p</em> has a limited impact on the deformation behavior and mechanical property evolution of the frozen soil. In contrast, <em>b</em> and <em>R</em> significantly influence the mechanical properties of frozen soil. When <em>b</em> and <em>R</em> at low values, the continuous rotation of principal stress causes axial strain to develop positively, decreases the mechanical property parameter damping ratio, increases the elastic modulus, and densified the sample. However, with the increase in <em>b</em> and <em>R</em> beyond a threshold, the repeated principal stress rotation causes the axial strain to develop negatively, increases the damping ratio continuously, decreases elastic modulus, and leads to significant softening of the frozen soil with an increase in rotation cycles.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104368"},"PeriodicalIF":3.8,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Chemical composition and properties of Ski wax: A comprehensive analysis of fluorinated, non-fluorinated, and bio-based waxes","authors":"Lorenz Cushman, Justin Zsiros, Gus Kaeding, Jeffrey Bates","doi":"10.1016/j.coldregions.2024.104365","DOIUrl":"10.1016/j.coldregions.2024.104365","url":null,"abstract":"<div><div>This study analyzes the chemical composition and thermal properties of various ski wax materials, including fluorinated, non-fluorinated petroleum-based, and bio-based waxes. Advanced characterization techniques (FTIR, EDS, and DSC) were used to investigate the chemical functionality, elemental composition, and thermal behavior of these waxes. Fluorinated powder waxes were found to be composed almost entirely of fluorocarbons, while solid fluorinated waxes are primarily hydrocarbons with minimal fluorine content. Bio-based waxes exhibit unique ester and carboxylic acid functional groups. Different brands, models, and suggested temperature uses of waxes within the same physical and chemical type show similar chemical compositions. While petroleum-based compared to bio-based waxes show a significant difference in chemical structure. EDS analysis identified silicon, magnesium, and aluminum in certain waxes, possibly indicating the use of additives. DSC results showed similar thermal behavior at sub-freezing temperatures. This research lays the groundwork for understanding ski wax material science and opens up new avenues for future investigation and innovation in the ski and ski wax industry.</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"230 ","pages":"Article 104365"},"PeriodicalIF":3.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}