首页 > 最新文献

Ocean Systems Engineering-An International Journal最新文献

英文 中文
Manufacturing process improvement of offshore plant: Process mining technique and case study 海上工厂制造工艺改进:工艺挖掘技术与案例研究
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2019-01-01 DOI: 10.12989/OSE.2019.9.3.329
Sung-chul Shin, S. Y. Kim, Chun-myoung Noh, Soon-Sup Lee, Jae-chul Lee
{"title":"Manufacturing process improvement of offshore plant: Process mining technique and case study","authors":"Sung-chul Shin, S. Y. Kim, Chun-myoung Noh, Soon-Sup Lee, Jae-chul Lee","doi":"10.12989/OSE.2019.9.3.329","DOIUrl":"https://doi.org/10.12989/OSE.2019.9.3.329","url":null,"abstract":"","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"9 1","pages":"329-347"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66504664","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
Coupled CFD-FEM simulation of hydrodynamic responses of a CALM buoy CALM浮筒水动力响应的CFD-FEM耦合模拟
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2019-01-01 DOI: 10.12989/OSE.2019.9.1.021
Haoyuan Gu, Hamn-Ching Chen, L. Zhao
. In this paper, the Finite-Analytic Navier-Stokes (FANS) code is coupled with an in-house finite-element code to study the dynamic interaction between a floating buoy and its mooring system. Hydrodynamic loads on the buoy are predicted with the FANS module, in which Large Eddy Simulation (LES) is used as the turbulence model. The mooring lines are modeled based on a slender body theory. Their dynamic responses are simulated with a nonlinear finite element module, MOORING3D. The two modules are coupled by transferring the forces and displacements of the buoy and its mooring system at their connections through an interface module. A free-decay model test was used to calibrate the coupled method. In addition, to investigate the capability of the present coupled method, numerical simulations of two degree-of-freedom vortex-induced motion of a CALM buoy in uniform currents were performed. With the study it can be verified that accurate predictions of the motion responses and tension responses of the CALM buoy system can be made with the coupling CFD-FEM method.
。本文将有限解析Navier-Stokes (FANS)程序与内部有限元程序相结合,研究浮筒与其系泊系统之间的动力相互作用。采用大涡模拟(Large Eddy Simulation, LES)作为湍流模型的FANS模块对浮筒的水动力载荷进行了预测。系泊线是基于细长体理论建模的。利用非线性有限元模块MOORING3D对其动力响应进行了仿真。这两个模块通过接口模块将浮筒及其系泊系统在连接处的力和位移相互耦合。采用自由衰减模型试验对耦合方法进行了标定。此外,为了验证该耦合方法的性能,对CALM浮标在均匀水流中两自由度涡致运动进行了数值模拟。通过研究验证了CFD-FEM耦合方法可以准确预测CALM浮筒系统的运动响应和张力响应。
{"title":"Coupled CFD-FEM simulation of hydrodynamic responses of a CALM buoy","authors":"Haoyuan Gu, Hamn-Ching Chen, L. Zhao","doi":"10.12989/OSE.2019.9.1.021","DOIUrl":"https://doi.org/10.12989/OSE.2019.9.1.021","url":null,"abstract":". In this paper, the Finite-Analytic Navier-Stokes (FANS) code is coupled with an in-house finite-element code to study the dynamic interaction between a floating buoy and its mooring system. Hydrodynamic loads on the buoy are predicted with the FANS module, in which Large Eddy Simulation (LES) is used as the turbulence model. The mooring lines are modeled based on a slender body theory. Their dynamic responses are simulated with a nonlinear finite element module, MOORING3D. The two modules are coupled by transferring the forces and displacements of the buoy and its mooring system at their connections through an interface module. A free-decay model test was used to calibrate the coupled method. In addition, to investigate the capability of the present coupled method, numerical simulations of two degree-of-freedom vortex-induced motion of a CALM buoy in uniform currents were performed. With the study it can be verified that accurate predictions of the motion responses and tension responses of the CALM buoy system can be made with the coupling CFD-FEM method.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"727 1","pages":"21-42"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66503133","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
A site-specific CFD study of passing ship effects on multiple moored ships 多艘系泊船舶过船效应的CFD研究
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2019-01-01 DOI: 10.12989/OSE.2019.9.1.043
Hamn-Ching Chen, Chia-Rong Chen, E. Huang
A local-analytic-based Navier-Stokes solver has been employed in conjunction with a compound ocean structure motion analysis program for time-domain simulation of passing ship effects induced by multiple post-Panamax class ships in the exact condition of a real waterway. The exact seabed bathymetry was reproduced to the utmost precision attainable using the NOAA geophysical database for Virginia Beach, NOAA nautical charts for Hampton Roads and Norfolk harbor, and echo sounding data for the navigation channel and waterfront facilities. A parametric study consists of 112 simulation cases with various combinations of ship lanes, ship speeds, ship heading (inbound or outbound), channel depths, drift angles, and passing ship coupling (in head-on or overtaking encounters) were carried out for two waterfront facilities at NAVSTA Norfolk and Craney Island Fuel Terminal. The present paper provides detailed parametric study results at both locations to investigate the site-specific passing ship effects on the motion responses of ships moored at nearby piers.
采用基于局部解析的Navier-Stokes解算器,结合复合海洋结构运动分析程序,对在真实航道的精确条件下多艘超巴拿马型船舶的过船效应进行了时域模拟。利用美国国家海洋和大气管理局(NOAA)弗吉尼亚海滩的地球物理数据库、汉普顿路和诺福克港的NOAA海图,以及航道和海滨设施的回声探测数据,精确地再现了海底测深数据,达到了最高的精度。对NAVSTA诺福克和Craney岛燃料码头的两个滨水设施进行了参数化研究,包括112个模拟案例,包括船舶航道、船速、船舶航向(入港或出港)、航道深度、漂移角和过往船舶耦合(迎面或超车)的各种组合。本文提供了两个地点的详细参数研究结果,以研究特定地点的过船对停泊在附近码头的船舶运动响应的影响。
{"title":"A site-specific CFD study of passing ship effects on multiple moored ships","authors":"Hamn-Ching Chen, Chia-Rong Chen, E. Huang","doi":"10.12989/OSE.2019.9.1.043","DOIUrl":"https://doi.org/10.12989/OSE.2019.9.1.043","url":null,"abstract":"A local-analytic-based Navier-Stokes solver has been employed in conjunction with a compound ocean structure motion analysis program for time-domain simulation of passing ship effects induced by multiple post-Panamax class ships in the exact condition of a real waterway. The exact seabed bathymetry was reproduced to the utmost precision attainable using the NOAA geophysical database for Virginia Beach, NOAA nautical charts for Hampton Roads and Norfolk harbor, and echo sounding data for the navigation channel and waterfront facilities. A parametric study consists of 112 simulation cases with various combinations of ship lanes, ship speeds, ship heading (inbound or outbound), channel depths, drift angles, and passing ship coupling (in head-on or overtaking encounters) were carried out for two waterfront facilities at NAVSTA Norfolk and Craney Island Fuel Terminal. The present paper provides detailed parametric study results at both locations to investigate the site-specific passing ship effects on the motion responses of ships moored at nearby piers.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"9 1","pages":"43-77"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66503447","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
Big data-based piping material analysis framework in offshore structure for contract design 基于大数据的海上结构合同设计管道材料分析框架
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2019-01-01 DOI: 10.12989/OSE.2019.9.1.079
Min-jae Oh, M. Roh, Sung-Woo Park, Do-Hyun Chun, S. Myung
. The material analysis of an offshore structure is generally conducted in the contract design phase for the price quotation of a new offshore project. This analysis is conducted manually by an engineer, which is time-consuming and can lead to inaccurate results, because the data size from previous projects is too large, and there are so many materials to consider. In this study, the piping materials in an offshore structure are analyzed for contract design using a big data framework. The big data technologies used include HDFS (Hadoop Distributed File System) for data saving, Hive and HBase for the database to handle the saved data, Spark and Kylin for data processing, and Zeppelin for user interface and visualization. The analyzed results show that the proposed big data framework can reduce the efforts put toward contract design in the estimation of the piping material cost.
. 海上结构物的材料分析一般在海上新项目报价的合同设计阶段进行。这种分析是由工程师手动进行的,这是耗时的,并且可能导致不准确的结果,因为以前项目的数据大小太大,需要考虑的材料太多了。在本研究中,使用大数据框架对海上结构中的管道材料进行了合同设计分析。使用的大数据技术包括HDFS (Hadoop分布式文件系统)进行数据保存,Hive和HBase进行数据库处理,Spark和麒麟进行数据处理,Zeppelin进行用户界面和可视化。分析结果表明,提出的大数据框架可以减少合同设计在管道材料成本估算中的工作量。
{"title":"Big data-based piping material analysis framework in offshore structure for contract design","authors":"Min-jae Oh, M. Roh, Sung-Woo Park, Do-Hyun Chun, S. Myung","doi":"10.12989/OSE.2019.9.1.079","DOIUrl":"https://doi.org/10.12989/OSE.2019.9.1.079","url":null,"abstract":". The material analysis of an offshore structure is generally conducted in the contract design phase for the price quotation of a new offshore project. This analysis is conducted manually by an engineer, which is time-consuming and can lead to inaccurate results, because the data size from previous projects is too large, and there are so many materials to consider. In this study, the piping materials in an offshore structure are analyzed for contract design using a big data framework. The big data technologies used include HDFS (Hadoop Distributed File System) for data saving, Hive and HBase for the database to handle the saved data, Spark and Kylin for data processing, and Zeppelin for user interface and visualization. The analyzed results show that the proposed big data framework can reduce the efforts put toward contract design in the estimation of the piping material cost.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"9 1","pages":"79-95"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66503595","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: 3
Risk analysis of offshore terminals in the Caspian Sea 里海近海码头的风险分析
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2019-01-01 DOI: 10.12989/ose.2019.9.3.261
K. Mokhtari, J. Amanee
. Nowadays in offshore industry there are emerging hazards with vague property such as act of terrorism, act of war, unforeseen natural disasters such as tsunami, etc. Therefore industry professionals such as offshore energy insurers, safety engineers and risk managers in order to determine the failure rates and frequencies for the potential hazards where there is no data available, they need to use an appropriate method to overcome this difficulty. Furthermore in conventional risk based analysis models such as when using a fault tree analysis, hazards with vague properties are normally waived and ignored. In other word in previous situations only a traditional probability based fault tree analysis could be implemented. To overcome this shortcoming fuzzy set theory is applied to fault tree analysis to combine the known and unknown data in which the pre-combined result will be determined under a fuzzy environment. This has been fulfilled by integration of a generic bow-tie based risk analysis model into the risk assessment phase of the Risk Management (RM) cycles as a backbone of the phase. For this reason Fault Tree Analysis (FTA) and Event Tree Analysis (ETA) are used to analyse one of the significant risk factors associated in offshore terminals. This process will eventually help the insurers and risk managers in marine and offshore industries to investigate the potential hazards more in detail if there is vagueness. For this purpose a case study of offshore terminal while coinciding with the nature of the Caspian Sea was decided to be examined.
. 目前海上工业中出现了一些性质模糊的新灾害,如恐怖主义行为、战争行为、海啸等不可预见的自然灾害等。因此,海上能源保险公司、安全工程师和风险管理人员等行业专业人士在没有可用数据的情况下,为了确定潜在危险的故障率和频率,他们需要使用适当的方法来克服这一困难。此外,在传统的基于风险的分析模型中,例如在使用故障树分析时,通常会放弃和忽略具有模糊属性的危险。换句话说,在以前的情况下,只能实现传统的基于概率的故障树分析。为了克服这一缺点,将模糊集理论应用到故障树分析中,将已知和未知数据结合起来,在模糊环境下确定预组合结果。这是通过将基于领结的通用风险分析模型集成到风险管理(RM)周期的风险评估阶段作为该阶段的支柱来实现的。因此,使用故障树分析(FTA)和事件树分析(ETA)来分析海上码头相关的重要风险因素之一。这一过程最终将帮助船舶和近海工业的保险公司和风险管理人员更详细地调查潜在的危险,如果存在模糊性。为此目的,决定对符合里海性质的近海码头进行个案研究。
{"title":"Risk analysis of offshore terminals in the Caspian Sea","authors":"K. Mokhtari, J. Amanee","doi":"10.12989/ose.2019.9.3.261","DOIUrl":"https://doi.org/10.12989/ose.2019.9.3.261","url":null,"abstract":". Nowadays in offshore industry there are emerging hazards with vague property such as act of terrorism, act of war, unforeseen natural disasters such as tsunami, etc. Therefore industry professionals such as offshore energy insurers, safety engineers and risk managers in order to determine the failure rates and frequencies for the potential hazards where there is no data available, they need to use an appropriate method to overcome this difficulty. Furthermore in conventional risk based analysis models such as when using a fault tree analysis, hazards with vague properties are normally waived and ignored. In other word in previous situations only a traditional probability based fault tree analysis could be implemented. To overcome this shortcoming fuzzy set theory is applied to fault tree analysis to combine the known and unknown data in which the pre-combined result will be determined under a fuzzy environment. This has been fulfilled by integration of a generic bow-tie based risk analysis model into the risk assessment phase of the Risk Management (RM) cycles as a backbone of the phase. For this reason Fault Tree Analysis (FTA) and Event Tree Analysis (ETA) are used to analyse one of the significant risk factors associated in offshore terminals. This process will eventually help the insurers and risk managers in marine and offshore industries to investigate the potential hazards more in detail if there is vagueness. For this purpose a case study of offshore terminal while coinciding with the nature of the Caspian Sea was decided to be examined.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"9 1","pages":"261-285"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66504629","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 zonal hybrid approach coupling FNPT with OpenFOAM for modelling wave-structure interactions with action of current 将FNPT与OpenFOAM耦合的区域混合方法用于模拟有电流作用的波-结构相互作用
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2018-12-31 DOI: 10.12989/OSE.2018.8.4.381
Qian Li, Jinghua Wang, S. Yan, Jiaye Gong, Q. Ma
This paper presents a hybrid numerical approach, which combines a two-phase Navier- Stokes model (NS) and the fully nonlinear potential theory (FNPT), for modelling wave-structure interaction. The former governs the computational domain near the structure, where the viscous and turbulent effects are significant, and is solved by OpenFOAM/InterDyMFoam which utilising the finite volume method (FVM) with a Volume of Fluid (VOF) for the phase identification. The latter covers the rest of the domain, where the fluid may be considered as incompressible, inviscid and irrotational, and solved by using the Quasi Arbitrary Lagrangian- Eulerian finite element method (QALE-FEM). These two models are weakly coupled using a zonal (spatially hierarchical) approach. Considering the inconsistence of the solutions at the boundaries between two different sub-domains governed by two fundamentally different models, a relaxation (transitional) zone is introduced, where the velocity, pressure and surface elevations are taken as the weighted summation of the solutions by two models. In order to tackle the challenges associated and maximise the computational efficiency, further developments of the QALE-FEM have been made. These include the derivation of an arbitrary Lagrangian- Eulerian FNPT and application of a robust gradient calculation scheme for estimating the velocity. The present hybrid model is applied to the numerical simulation of a fixed horizontal cylinder subjected to a unidirectional wave with or without following current. The convergence property, the optimisation of the relaxation zone, the accuracy and the computational efficiency are discussed. Although the idea of the weakly coupling using the zonal approach is not new, the present hybrid model is the first one to couple the QALE-FEM with OpenFOAM solver and/or to be applied to numerical simulate the wave-structure interaction with presence of current.
本文提出了一种混合数值方法,将两相Navier-Stokes模型(NS)和全非线性势理论(FNPT)相结合,用于模拟波-结构相互作用。前者控制结构附近的计算域,其中粘性和湍流效应显著,并通过OpenFOAM/InterDyMFoam解决,该方法利用有限体积法(FVM)和流体体积法(VOF)进行相位识别。后者涵盖了该领域的其余部分,其中流体可以被认为是不可压缩的、无粘性的和无旋转的,并通过使用准任意拉格朗日-欧拉有限元方法(QALE-FEM)求解。这两个模型使用区域(空间层次)方法进行弱耦合。考虑到由两个根本不同的模型控制的两个不同子域之间的边界处的解的不一致性,引入了松弛(过渡)区,其中速度、压力和表面高程被视为两个模型解的加权总和。为了应对相关挑战并最大限度地提高计算效率,对QALE-FEM进行了进一步的开发。其中包括推导任意拉格朗日-欧拉FNPT,以及应用稳健梯度计算方案来估计速度。将该混合模型应用于固定水平圆柱体在有或无跟随电流的单向波作用下的数值模拟。讨论了收敛性、松弛区的优化、精度和计算效率。尽管使用分区方法进行弱耦合的想法并不新鲜,但目前的混合模型是第一个将QALE-FEM与OpenFOAM求解器耦合和/或应用于数值模拟存在电流的波浪-结构相互作用的模型。
{"title":"A zonal hybrid approach coupling FNPT with OpenFOAM for modelling wave-structure interactions with action of current","authors":"Qian Li, Jinghua Wang, S. Yan, Jiaye Gong, Q. Ma","doi":"10.12989/OSE.2018.8.4.381","DOIUrl":"https://doi.org/10.12989/OSE.2018.8.4.381","url":null,"abstract":"This paper presents a hybrid numerical approach, which combines a two-phase Navier- Stokes model (NS) and the fully nonlinear potential theory (FNPT), for modelling wave-structure interaction. The former governs the computational domain near the structure, where the viscous and turbulent effects are significant, and is solved by OpenFOAM/InterDyMFoam which utilising the finite volume method (FVM) with a Volume of Fluid (VOF) for the phase identification. The latter covers the rest of the domain, where the fluid may be considered as incompressible, inviscid and irrotational, and solved by using the Quasi Arbitrary Lagrangian- Eulerian finite element method (QALE-FEM). These two models are weakly coupled using a zonal (spatially hierarchical) approach. Considering the inconsistence of the solutions at the boundaries between two different sub-domains governed by two fundamentally different models, a relaxation (transitional) zone is introduced, where the velocity, pressure and surface elevations are taken as the weighted summation of the solutions by two models. In order to tackle the challenges associated and maximise the computational efficiency, further developments of the QALE-FEM have been made. These include the derivation of an arbitrary Lagrangian- Eulerian FNPT and application of a robust gradient calculation scheme for estimating the velocity. The present hybrid model is applied to the numerical simulation of a fixed horizontal cylinder subjected to a unidirectional wave with or without following current. The convergence property, the optimisation of the relaxation zone, the accuracy and the computational efficiency are discussed. Although the idea of the weakly coupling using the zonal approach is not new, the present hybrid model is the first one to couple the QALE-FEM with OpenFOAM solver and/or to be applied to numerical simulate the wave-structure interaction with presence of current.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"64 3","pages":"381-407"},"PeriodicalIF":0.9,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41295462","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: 19
Fuzzy event tree analysis for quantified risk assessment due to oil and gas leakage in offshore installations 海上设施油气泄漏风险量化评估的模糊事件树分析
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2018-03-01 DOI: 10.12989/OSE.2018.8.1.041
A. S. Cheliyan, S. K. Bhattacharyya
Accidental oil and gas leak is a critical concern for the offshore industry because it can lead to severe consequences and as a result, it is imperative to evaluate the probabilities of occurrence of the consequences of the leakage in order to assess the risk. Event Tree Analysis (ETA) is a technique to identify the consequences that can result from the occurrence of a hazardous event. The probability of occurrence of the consequences is evaluated by the ETA, based on the failure probabilities of the sequential events. Conventional ETA deals with events with crisp failure probabilities. In offshore applications, it is often difficult to arrive at a single probability measure due to lack of data or imprecision in data. In such a scenario, fuzzy set theory can be applied to handle imprecision and data uncertainty. This paper presents fuzzy ETA (FETA) methodology to compute the probability of the outcomes initiated due to oil/gas leak in an actual offshore-onshore installation. Post FETA, sensitivity analysis by Fuzzy Weighted Index (FWI) method is performed to find the event that has the maximum contribution to the severe sequences. It is found that events of „ignition‟, spreading of fire to „equipment‟ and „other areas‟ are the highest contributors to the severe consequences, followed by failure of „leak detection‟ and „fire detection‟ and „fire water not being effective‟. It is also found that the frequency of severe consequences that are catastrophic in nature obtained by ETA is one order less than that obtained by FETA, thereby implying that in ETA, the uncertainty does not propagate through the event tree. The ranking of severe sequences based on their probability, however, are identical in both ETA and FETA.
石油和天然气意外泄漏是海上工业的一个关键问题,因为它可能会导致严重后果,因此,必须评估泄漏后果发生的可能性,以评估风险。事件树分析(ETA)是一种识别危险事件发生可能导致的后果的技术。根据顺序事件的失效概率,通过ETA评估后果发生的概率。传统ETA处理具有明确故障概率的事件。在海上应用中,由于缺乏数据或数据不精确,通常很难得出单一的概率测度。在这种情况下,模糊集理论可以用于处理不精确性和数据不确定性。本文提出了模糊ETA(FETA)方法来计算实际海上陆上装置中由于石油/天然气泄漏而引发的结果的概率。在FETA之后,通过模糊加权指数(FWI)方法进行灵敏度分析,以找到对严重序列贡献最大的事件。研究发现,“点火”事件、火灾蔓延至“设备”和“其他区域”是造成严重后果的最大因素,其次是“泄漏检测”和“火灾检测”失败以及“消防水无效”。还发现,ETA获得的灾难性严重后果的频率比FETA获得的频率低一个数量级,从而意味着在ETA中,不确定性不会通过事件树传播。然而,基于严重序列概率的排序在ETA和FETA中是相同的。
{"title":"Fuzzy event tree analysis for quantified risk assessment due to oil and gas leakage in offshore installations","authors":"A. S. Cheliyan, S. K. Bhattacharyya","doi":"10.12989/OSE.2018.8.1.041","DOIUrl":"https://doi.org/10.12989/OSE.2018.8.1.041","url":null,"abstract":"Accidental oil and gas leak is a critical concern for the offshore industry because it can lead to severe consequences and as a result, it is imperative to evaluate the probabilities of occurrence of the consequences of the leakage in order to assess the risk. Event Tree Analysis (ETA) is a technique to identify the consequences that can result from the occurrence of a hazardous event. The probability of occurrence of the consequences is evaluated by the ETA, based on the failure probabilities of the sequential events. Conventional ETA deals with events with crisp failure probabilities. In offshore applications, it is often difficult to arrive at a single probability measure due to lack of data or imprecision in data. In such a scenario, fuzzy set theory can be applied to handle imprecision and data uncertainty. This paper presents fuzzy ETA (FETA) methodology to compute the probability of the outcomes initiated due to oil/gas leak in an actual offshore-onshore installation. Post FETA, sensitivity analysis by Fuzzy Weighted Index (FWI) method is performed to find the event that has the maximum contribution to the severe sequences. It is found that events of „ignition‟, spreading of fire to „equipment‟ and „other areas‟ are the highest contributors to the severe consequences, followed by failure of „leak detection‟ and „fire detection‟ and „fire water not being effective‟. It is also found that the frequency of severe consequences that are catastrophic in nature obtained by ETA is one order less than that obtained by FETA, thereby implying that in ETA, the uncertainty does not propagate through the event tree. The ranking of severe sequences based on their probability, however, are identical in both ETA and FETA.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"8 1","pages":"41"},"PeriodicalIF":0.9,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46530599","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: 4
The effects of blade-pitch control on the performance of semi-submersible-type floating offshore wind turbines 桨距控制对半潜式浮动海上风力发电机性能的影响
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2018-03-01 DOI: 10.12989/ose.2018.8.1.079
H. C. Kim, Moo-Hyun Kim
{"title":"The effects of blade-pitch control on the performance of semi-submersible-type floating offshore wind turbines","authors":"H. C. Kim, Moo-Hyun Kim","doi":"10.12989/ose.2018.8.1.079","DOIUrl":"https://doi.org/10.12989/ose.2018.8.1.079","url":null,"abstract":"","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"8 1","pages":"79"},"PeriodicalIF":0.9,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44222344","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
Dynamic analysis of water storage tank with rigid block at bottom 底部刚性块贮水箱的动力分析
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2018-03-01 DOI: 10.12989/OSE.2018.8.1.057
R. Adhikary, K. Mandal
The present paper deals with the finite element analysis of water tanks with rigid baffle. Fluid is discretized by two dimensional eight-node isoparametric elements and the governing equation is simulated by pressure based formulation to reduce the degrees of freedom in the domain. Both free vibration and force vibration analysis are carried out for different sizes and positions of block at tank bottom. The fundamental frequency depends on block height and it reduces with the increase of block height. The variation of hydrodynamic pressure on tank walls not only depends of the exciting frequency but also on the size and position of rigid block at tank bottom. The hydrodynamic pressure has higher value when the exciting frequency is equal and lower than the fundamental frequency of the water in the tank. Similarly, the hydrodynamic pressure increases with the increase of width of the block for all exciting frequencies when the block is at the centre of tank. The left and right walls of tank have experienced different hydrodynamic pressure when the block is placed at off-centre. However, the increase in hydrodynamic pressure on nearest tank wall becomes insignificant after a certain value of the distance between the wall and the rigid block.
本文对带有刚性挡板的水箱进行了有限元分析。采用二维八节点等参单元对流体进行离散化,并采用基于压力的公式对控制方程进行模拟,降低了区域内的自由度。对罐底块体的不同尺寸和位置进行了自由振动和力振动分析。基频与块高有关,随着块高的增加而减小。罐壁动水压力的变化不仅与激振频率有关,还与罐底刚性块的大小和位置有关。当激励频率等于且低于水箱内水的基频时,水动压力值较高。同样,在各激振频率下,液动压力随滑车宽度的增加而增加,当滑车位于水箱中心时。当缸体偏离中心位置时,罐左右壁受到不同的动水压力。然而,当罐壁与刚性块之间的距离达到一定值后,最近的罐壁动水压力的增加变得不明显。
{"title":"Dynamic analysis of water storage tank with rigid block at bottom","authors":"R. Adhikary, K. Mandal","doi":"10.12989/OSE.2018.8.1.057","DOIUrl":"https://doi.org/10.12989/OSE.2018.8.1.057","url":null,"abstract":"The present paper deals with the finite element analysis of water tanks with rigid baffle. Fluid is discretized by two dimensional eight-node isoparametric elements and the governing equation is simulated by pressure based formulation to reduce the degrees of freedom in the domain. Both free vibration and force vibration analysis are carried out for different sizes and positions of block at tank bottom. The fundamental frequency depends on block height and it reduces with the increase of block height. The variation of hydrodynamic pressure on tank walls not only depends of the exciting frequency but also on the size and position of rigid block at tank bottom. The hydrodynamic pressure has higher value when the exciting frequency is equal and lower than the fundamental frequency of the water in the tank. Similarly, the hydrodynamic pressure increases with the increase of width of the block for all exciting frequencies when the block is at the centre of tank. The left and right walls of tank have experienced different hydrodynamic pressure when the block is placed at off-centre. However, the increase in hydrodynamic pressure on nearest tank wall becomes insignificant after a certain value of the distance between the wall and the rigid block.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"8 1","pages":"57"},"PeriodicalIF":0.9,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42187505","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
A study on underwater optical wireless communication link capability in the Bay of Bengal 孟加拉湾水下光无线通信链路性能研究
IF 0.9 Q4 ENGINEERING, OCEAN Pub Date : 2018-03-01 DOI: 10.12989/OSE.2018.8.1.033
V. Sathyaram, S. Prince, N. Vedachalam
The paper presents a numerical underwater channel model developed in MATLAB for estimating the optical link budget between a light emitting diode (LED) based optical transmitter and a photo diode (PD) receiver when operated in the harbor, coastal and deep waters locations in the Bay of Bengal. The water samples are collected at different locations in the Bay of Bengal using a water sampler during an offshore research cruise. The optical attenuation, the main inherent parameter determining the range of the optical communication link is identified for the different waters using an underwater irradiance measurement system in the laboratory. The identified parameters are applied to the numerical model and found that a 10 W LED and a photo diode based system can provide the optical budget required for a horizontal underwater communication range of about 0.5, 14 and 35 m in the harbor, coastal and deep waters locations respectively. By increasing the transmitter power to 50 W, the operating range of the communication link could be increased up to 53 m in deep water locations in the Bay of Bengal.
本文提出了一个在MATLAB中开发的水下通道数值模型,用于估计在孟加拉湾港口、沿海和深水位置运行时基于发光二极管(LED)的光发射器和光电二极管(PD)接收器之间的光链路预算。在海上研究巡航期间,使用采样器在孟加拉湾的不同地点采集了水样。在实验室中使用水下辐照度测量系统识别不同水域的光衰减,这是确定光通信链路范围的主要固有参数。将识别的参数应用于数值模型,发现10W LED和基于光电二极管的系统可以分别在港口、沿海和深水位置提供约0.5米、14米和35米的水平水下通信范围所需的光学预算。通过将发射机功率增加到50 W,在孟加拉湾的深水位置,通信链路的工作范围可以增加到53 m。
{"title":"A study on underwater optical wireless communication link capability in the Bay of Bengal","authors":"V. Sathyaram, S. Prince, N. Vedachalam","doi":"10.12989/OSE.2018.8.1.033","DOIUrl":"https://doi.org/10.12989/OSE.2018.8.1.033","url":null,"abstract":"The paper presents a numerical underwater channel model developed in MATLAB for estimating the optical link budget between a light emitting diode (LED) based optical transmitter and a photo diode (PD) receiver when operated in the harbor, coastal and deep waters locations in the Bay of Bengal. The water samples are collected at different locations in the Bay of Bengal using a water sampler during an offshore research cruise. The optical attenuation, the main inherent parameter determining the range of the optical communication link is identified for the different waters using an underwater irradiance measurement system in the laboratory. The identified parameters are applied to the numerical model and found that a 10 W LED and a photo diode based system can provide the optical budget required for a horizontal underwater communication range of about 0.5, 14 and 35 m in the harbor, coastal and deep waters locations respectively. By increasing the transmitter power to 50 W, the operating range of the communication link could be increased up to 53 m in deep water locations in the Bay of Bengal.","PeriodicalId":44219,"journal":{"name":"Ocean Systems Engineering-An International Journal","volume":"8 1","pages":"033"},"PeriodicalIF":0.9,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44944226","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
期刊
Ocean Systems Engineering-An International Journal
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1