Volume 7: Polar and Arctic Sciences and Technology最新文献

Numerical Modelling of Ice Rubble Interactions Using Discrete Element Method 冰-碎石相互作用的离散元数值模拟

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-62818

Lei Liu, E. Bailey, R. Taylor, T. King

{"title":"Numerical Modelling of Ice Rubble Interactions Using Discrete Element Method","authors":"Lei Liu, E. Bailey, R. Taylor, T. King","doi":"10.1115/omae2021-62818","DOIUrl":"https://doi.org/10.1115/omae2021-62818","url":null,"abstract":"\u0000 A three-dimensional, freeze-bonded, Discrete Element Method (DEM) numerical model has been developed to simulate various ice rubble/ridge interaction scenarios. The numerical model was validated against the physical tests conducted by C-CORE under the Pipeline Ice Risk Assessment and Mitigation (PIRAM) Joint Industry Project. Accurate representation of ice block geometries and sizes distributions was achieved using clumped particles, rather than the traditional DEM spheres. With the use of clumped ice blocks the numerical model was able to characterize the initial keel conditions (macro porosity and freeze bond contacts) and capture interlocking behavior between ice blocks. A DEM gravel seabed model was then introduced to the clumped ice block model to allow for better representation of soil response during the simulated experiments. The main features of these model developments are described in this paper, along with a comparison of simulated results and large scale physical test results. From this work it was concluded that: (1) clumped ice blocks give more representative ice block shapes for an ice keel than spherical ice blocks, which better capture ice block interactions and overall ridge keel properties and behavior; and (2) a DEM model of the seabed gravel provided a better representation of the seabed than was possible with a continuous stiffness plane, which had important implications for modelling the keel-seabed interactions. The development and inclusion of these two new model features were found to significantly improve the accuracy of the DEM model in reproducing physical test results, while still being sufficiently computationally efficient as to allow for simulation of interactions full-scale ice ridges.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129274304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Effects of Hull Geometry and Tightness of Turns on Ship Maneuverability: An OSIS-IHI Simulation 船体几何形状和转弯紧密性对船舶操纵性的影响:一个sis - ihi仿真

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-63453

M. Lau

{"title":"Effects of Hull Geometry and Tightness of Turns on Ship Maneuverability: An OSIS-IHI Simulation","authors":"M. Lau","doi":"10.1115/omae2021-63453","DOIUrl":"https://doi.org/10.1115/omae2021-63453","url":null,"abstract":"\u0000 OSIS-IHI (Ocean Structure Interaction Simulator – Ice-Hull Interaction) is a ship maneuvering in ice modeling software developed at OCRE for a marine simulator and ship performance assessment applications. A series of OSIS-IHI simulations is conducted to explain the maneuvering behavior observed of the USCGC Polar Icebreaker indicative design previously tested at the centre. The simulation is conducted with the original and a modified version of the USCGC Icebreaker Healy. The Icebreaker USCGC Healy was equipped with doublescrew conventional propellers. The hull geometry of the OSIS-Healy model is appropriately modified to mimic the hull form of two indicated design versions in question and its propulsion units replaced by twin pods prior to studying its maneuverability in order to shed light on the apparently poor maneuvering performance of the podded version of the indicative design. The modified version extends the mid-body leaving just 7.5 % of hull that constitutes the stern section. It is hypothesized that the extended mid-section cost large resisting moment against turning due to the increase of ice breaking at the aft shoulder and mid-body. This hypothesis is validated numerically to explain the poor maneuverability exhibited by the extended mid-body design, based on consideration of ice-hull interaction geometry and basic mechanics of ice breaking as well as existing anecdotal test evidences. This paper presents result of the simulation to explore effects of hull geometry and tightness of turns on ship maneuverability. Important insights gained are summarized and recommendation for further work given.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"276 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125615403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental Study of Combined Wave and Ice Loads on a Fixed Offshore Structure 海上固定结构波浪冰联合荷载试验研究

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-66442

S. Mintu, D. Molyneux

{"title":"Experimental Study of Combined Wave and Ice Loads on a Fixed Offshore Structure","authors":"S. Mintu, D. Molyneux","doi":"10.1115/omae2021-66442","DOIUrl":"https://doi.org/10.1115/omae2021-66442","url":null,"abstract":"\u0000 Ice floes in the marginal ice zone (MIZ) are exposed to wind, wave, and current forces which greatly influence the dynamics of the ice floes. ISO 19906 recommends considering combined wave and ice actions while designing offshore structures for arctic and cold regions. Few studies have focused on ice-structure interactions in waves. There are not many tools available to estimate these combined loads on structures. A numerical tool “SAMICE” has been developed to simulate the hydrodynamics of wave-ice interactions, but there exists a lack of data for a realistic MIZ under wave actions for validation studies of the numerical code.\u0000 To address this gap and to investigate the hydrodynamics of ice floes under waves, a set of experiments was conducted at the wave tank of Ocean Engineering Research Center (OERC) of Memorial University of Newfoundland. A six-component dynamometer was used to measure the loads on a model scale aluminum cylindrical gravity-based offshore structure. Loads were measured for five regular waves of various steepness in combination with three current speeds. Two ice concentrations with various floe sizes of random shapes were prepared from polypropylene sheets to represent the MIZ. Most of the tests were repeated three times and a statistical approach was used to analyze the loads. The preliminary analysis shows that the average wave-ice loads may be determined by ISO guidelines, but the predictions of impulse loads from individual wave-driven ice floes are very uncertain.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131370026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Probabilistic High-Pressure Zone Model of Dynamic Ice Structure Interactions and Associated Ice-Induced Vibrations 动态冰结构相互作用和相关冰激振动的概率高压区模型

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-62966

R. Hossain, R. Taylor, L. Moro

{"title":"A Probabilistic High-Pressure Zone Model of Dynamic Ice Structure Interactions and Associated Ice-Induced Vibrations","authors":"R. Hossain, R. Taylor, L. Moro","doi":"10.1115/omae2021-62966","DOIUrl":"https://doi.org/10.1115/omae2021-62966","url":null,"abstract":"\u0000 During ice-structure interactions that are dominated by ice compressive failure, the majority of the ice loads are transmitted through localized contact regions known as high-pressure zones (hpzs). This paper presents a probabilistic modelling framework for dynamic ice-structure interaction based on the mechanics of hpzs. Individual hpzs are modelled as a nonlinear spring-damper system where the stiffness is modelled as a function of nominal strain, with the degree of softening depending on the average strain-rate. Both spalling and crushing failure mechanisms were assessed in the context of periodical sinusoidal response. For spall dominated failure, the model structure showed presence of frequency lock-in in the speed range of 100–125mm/s, beyond which the failure was found to be random in nature with lower amplitude of structural response. The amplitude was also found to be significantly influenced by structural parameters with structural damping having the highest contribution. For pure crushing, an estimated equilibrium layer thickness based on theoretical calculations also showed presence of frequency lock-in. The work highlights the importance of understanding the interplay between these mechanisms, as well as the role of ice conditions and structural parameters on the processes that dominate an interaction.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124303638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Comparison of Inverse Models for the Estimation of Ice-Induced Propeller Moments on a Polar Vessel 极地船舶冰致螺旋桨力矩反演模型的比较

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-62755

B. M. Nickerson, A. Bekker

引用次数: 0

Assessment of Numerical Modeling Tools for the Prediction of Ship Performance in Ice 船舶在冰上性能预测的数值模拟工具评估

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-63452

M. Lau

{"title":"Assessment of Numerical Modeling Tools for the Prediction of Ship Performance in Ice","authors":"M. Lau","doi":"10.1115/omae2021-63452","DOIUrl":"https://doi.org/10.1115/omae2021-63452","url":null,"abstract":"\u0000 This paper provides a general review of available models used in the NRC-OCRE (National Research Council – Ocean, Coastal and River Engineering) that could be used to support the assessment of a ship’s performance in ice conditions. The models were separated into three main categories: empirical, numerical and real-time, and reviewed in terms of key strengths and weaknesses. A general overview of the modelling categories and specific models within each category is given. Within each modelling category, specific models were compared to outline the key features of both the independent models and the modelling category itself. A representative model within each category and sub-category was selected and used to present the output for a given scenario. This enabled a demonstration of output capabilities for each modelling category. It also provides the reader with additional information pertaining to the input requirements and validation for the selected models. A discussion of the integration of an ice loading model into an existing ship simulation framework is included. A specific case was reviewed in which a successful integration had occurred and was documented. This allowed for demonstration of a process that could be followed for updating one’s numerical modelling capabilities. Based on this review, guidance was provided in terms of selecting a numerical tool to extend current ship performance modelling capabilities to consider ice operations. Each modelling category and sub-category has a unique set of advantages and disadvantages. These should be considered in detail to ensure that the numerical model(s) selected are optimal in terms of their ability to assess desired scenarios and interface with existing software.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"128 45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132851632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Model for Ice Heterogeneity Affecting Bending Failure Against An Inclined Structure 冰非均质性对倾斜结构弯曲破坏的影响模型

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-62914

A. Simakina, P. Zvyagin, Mikhail Drepin

{"title":"A Model for Ice Heterogeneity Affecting Bending Failure Against An Inclined Structure","authors":"A. Simakina, P. Zvyagin, Mikhail Drepin","doi":"10.1115/omae2021-62914","DOIUrl":"https://doi.org/10.1115/omae2021-62914","url":null,"abstract":"\u0000 Experiments with model ice are usually carried out for preliminary assessment of ice qualities of designed offshore structures. Despite the fact that properties of model ice across artificial floe are constant, sometimes various experimental results can be explained not only by measurement errors.\u0000 The paper describes various positions of breaking points in a number of model experiments with an ice beam flexural failure. To explain the observed effect, the article suggests the hypothesis on heterogeneity of elastic modulus of an ice floe. The article considers a problem of possible influence of the area of heterogeneity on the position of an ice beam breaking point. Thus, the models of a cantilever beam and a plane lying on an elastic foundation with inconstant Young’s modulus are suggested. These models in form of their approximations by finite differences are applied for making numerical simulations in order to investigate the problem.\u0000 With the numerically obtained solutions of a cantilever beam and a plane on an elastic foundation with employed inhomogeneity of elastic modulus, the study observed noticeable change in the position of the breaking point when such inhomogeneity occurred close to the contact area.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122390154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Probabilistic Fatigue Assessment of a Mooring Line Based on Station-Keeping Trials in Ice 基于冰中保持试验的系泊缆绳疲劳概率评估

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-62924

C. Sinsabvarodom, B. Leira, W. Chai, A. Naess

{"title":"Probabilistic Fatigue Assessment of a Mooring Line Based on Station-Keeping Trials in Ice","authors":"C. Sinsabvarodom, B. Leira, W. Chai, A. Naess","doi":"10.1115/omae2021-62924","DOIUrl":"https://doi.org/10.1115/omae2021-62924","url":null,"abstract":"\u0000 The intention of this work is to perform a probabilistic fatigue assessment of a mooring line due to loads associated with the station-keeping of a ship in ice. In March 2017, the company Equinor (Statoil) conducted full-scale tests by means of station-keeping trials (SKT) in drifting ice in the Bay of Bothnia. The vessel Magne Viking was employed in order to represent a supply vessel equipped with a mooring line system, and the realtime loading during the full-scale measurement was recorded. The second vessel Tor Viking was serving as an ice breaker in order to maintain the physical ice management activities with different ice-breaking schemes, i.e. square updrift pattern, round circle pattern, circular updrift pattern and linear updrift pattern. The fatigue degradation corresponding to these different patterns were investigated. The peaks and valleys of the mooring tension are determined using the min peak prominence method. For the purpose of probabilistic fatigue assessment, the Rainflow-counting algorithm is applied to estimate the mooring stress range. Fatigue assessment based both on Rainflow counting and fitted probabilistic models were performed. For the latter, the stress range distributions from the observed data of mooring loads are fitted to various probability models in order to estimate the fatigue damage. It is found that the stress ranges represented by application of the Weibull distribution for the probabilistic fatigue approach provides results of the fatigue damage most similar to the Rainflow counting approach. Among the different scenarios of Ice management schemes, the circular updrift pattern provides the lowest magnitude of the fatigue degradation.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125791691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Condition Monitoring of Ship Propulsion Systems: State-of-the-Art, Development Trend and Role of Digital Twin 船舶推进系统状态监测:现状、发展趋势及数字孪生的作用

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-61847

A. Nejad, Etienne Purcell, M. Valavi, Roman Hudak, Benjamin Lehmann, F. Gutiérrez Guzmán, Felix Behrendt, Angelo Mario Bõhm, Franz von Bock und Polach, B. M. Nickerson, A. Bekker, Withold Drazyk

{"title":"Condition Monitoring of Ship Propulsion Systems: State-of-the-Art, Development Trend and Role of Digital Twin","authors":"A. Nejad, Etienne Purcell, M. Valavi, Roman Hudak, Benjamin Lehmann, F. Gutiérrez Guzmán, Felix Behrendt, Angelo Mario Bõhm, Franz von Bock und Polach, B. M. Nickerson, A. Bekker, Withold Drazyk","doi":"10.1115/omae2021-61847","DOIUrl":"https://doi.org/10.1115/omae2021-61847","url":null,"abstract":"\u0000 This paper describes the current implementations and development trends of condition monitoring as it pertains to ship propulsion systems. In terms of total incidents in the shipping industry in the last five years, failures relating to the propulsion system represent the majority. Condition monitoring offers effective early detection of failure which translates to increased reliability and decreased maintenance costs. Current industrial practices are often limited to performance monitoring rather than condition monitoring. Special focus is afforded to how condition monitoring is implemented on board ships, which regulatory codes are relevant and the summary of state-of-the-art research in marine machinery. Moreover, operation and monitoring in extreme environmental conditions, such as the Arctic and Antarctic with ice impact on the propulsion has been discussed. The new developments, in particular, digital twin approaches in health and condition monitoring have been highlighted, considering its pros and cons and potential challenges.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128259840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

The Impact of Cyclic Loading on the Flexural Strength of Ice 循环荷载对冰抗折强度的影响

Volume 7: Polar and Arctic Sciences and Technology Pub Date : 2021-06-21 DOI: 10.1115/omae2021-62289

Ihsan Kaplan, R. U. F. von Bock und Polach

{"title":"The Impact of Cyclic Loading on the Flexural Strength of Ice","authors":"Ihsan Kaplan, R. U. F. von Bock und Polach","doi":"10.1115/omae2021-62289","DOIUrl":"https://doi.org/10.1115/omae2021-62289","url":null,"abstract":"\u0000 Flexural strength measurements of sea ice in far inlying regions can experience continuous cyclic loading due to wave interactions. Furthermore, global warming leads to a continuous decrease of the Polar ice masses, resulting in an increased vulnerability of the integrity of the ice and its exposure to wave interactions and in consequence a growth of the marginal ice zone. In order to investigate the impact of cyclic loading on the flexural strength of ice, experiments with periodically loaded and previously unloaded ice samples is performed and analyzed. Previous research indicated both a weakening and a strengthening of the ice and the scope of this paper is also to enhance the understanding of the impact of cyclic loading of ice. This is relevant as ice might be subjected to several loading cycles before wave induced break-up and the question is whether the impact of cyclic loading needs to be accounted for in models. of its impact is addressed. The results show that the flexural strength of periodically loaded samples increases instead of fatigueing. Furthermore the ice has a very dynamic behaviour even at very low loading frequencies and small displacement-amplitudes in the micrometre range.","PeriodicalId":108271,"journal":{"name":"Volume 7: Polar and Arctic Sciences and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129539875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1