Pub Date : 2018-06-01DOI: 10.3940/RINA.IJME.2018.A2.476
R. Fışkın, H. Kişi, E. Nasibov
The development of soft computing techniques in recent years has encouraged researchers to study on the path planning problem in ship collision avoidance. These techniques have widely been implemented in marine industry and technology-oriented novel solutions have been introduced. Various models, methods and techniques have been proposed to solve the mentioned path planning problem with the aim of preventing reoccurrence of the problem and thus strengthening marine safety as well as providing fuel consumption efficiency. The purpose of this study is to scrutinize the models, methods and technologies proposed to settle the path planning issue in ship collision avoidance. The study also aims to provide certain bibliometric information which develops a literature map of the related field. For this purpose, a thorough literature review has been carried out. The results of the study have pointedly showed that the artificial intelligence methods, fuzzy logic and heuristic algorithms have greatly been used by the researchers who are interested in the related field.
{"title":"A Research on Techniques, Models and Methods Proposed for Ship Collision Avoidance Path Planning Problem","authors":"R. Fışkın, H. Kişi, E. Nasibov","doi":"10.3940/RINA.IJME.2018.A2.476","DOIUrl":"https://doi.org/10.3940/RINA.IJME.2018.A2.476","url":null,"abstract":"The development of soft computing techniques in recent years has encouraged researchers to study on the path planning problem in ship collision avoidance. These techniques have widely been implemented in marine industry and technology-oriented novel solutions have been introduced. Various models, methods and techniques have been proposed to solve the mentioned path planning problem with the aim of preventing reoccurrence of the problem and thus strengthening marine safety as well as providing fuel consumption efficiency. The purpose of this study is to scrutinize the models, methods and technologies proposed to settle the path planning issue in ship collision avoidance. The study also aims to provide certain bibliometric information which develops a literature map of the related field. For this purpose, a thorough literature review has been carried out. The results of the study have pointedly showed that the artificial intelligence methods, fuzzy logic and heuristic algorithms have greatly been used by the researchers who are interested in the related field.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133252839","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}
Pub Date : 2018-06-01DOI: 10.3940/rina.ijme.2018.a2.473
M. Pawłowski
Application of strip theory for the prediction of ship motions in waves relies on sectional hydrodynamic coefficients; i.e. the added mass and damping coefficients. These coefficients apply to linearised problems and are normally computed for inviscid fluids. It is possible to account for viscosity but this cannot be done by the RANS equations, as in linear problems there is no room for turbulence. The hydrodynamic coefficients can include the effect of viscosity but this can be done rightly through the classic Navier–Stokes equations for laminar (non-turbulent) flows. For solving these equations commercial RANS software can be used, assuming no Reynolds stresses.
{"title":"Viscosity in Seakeeping","authors":"M. Pawłowski","doi":"10.3940/rina.ijme.2018.a2.473","DOIUrl":"https://doi.org/10.3940/rina.ijme.2018.a2.473","url":null,"abstract":"Application of strip theory for the prediction of ship motions in waves relies on sectional hydrodynamic coefficients; i.e. the added mass and damping coefficients. These coefficients apply to linearised problems and are normally computed for inviscid fluids. It is possible to account for viscosity but this cannot be done by the RANS equations, as in linear problems there is no room for turbulence. The hydrodynamic coefficients can include the effect of viscosity but this can be done rightly through the classic Navier–Stokes equations for laminar (non-turbulent) flows. For solving these equations commercial RANS software can be used, assuming no Reynolds stresses.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115226868","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}
Pub Date : 2018-06-01DOI: 10.3940/rina.ijme.2018.a2.467
T. Li, C. An, Menglan Duan, H. Huang, W. Liang
This paper establishes a fast and accurate solution of the dynamic behaviours of subsea free-spanning pipelines under four different boundary conditions, based on GITT - the generalised integral transform technique. The fluid-structure interaction model is proposed by combining a linear structural equation and a non-linear distributed wake oscillator model, which simulates the effect of external current acting on the pipeline. The eigenvalue problems for the cross-flow vibration of the free-spanning submarine pipeline conveying internal fluid for four different boundary conditions are examined. The solution method of the natural frequency based on GITT is proposed. The explicit analytical formulae for the cross-flow displacement of the pipeline free span are derived, and the mode shapes and dynamic behaviours of the pipeline free span are discussed with different boundary conditions. The methodology and results in this paper can also expand to solving even more complicated boundary-value problems.
{"title":"Effect of the Boundary Conditions on the Dynamic Behaviours of Subsea Free-Spanning Pipelines","authors":"T. Li, C. An, Menglan Duan, H. Huang, W. Liang","doi":"10.3940/rina.ijme.2018.a2.467","DOIUrl":"https://doi.org/10.3940/rina.ijme.2018.a2.467","url":null,"abstract":"This paper establishes a fast and accurate solution of the dynamic behaviours of subsea free-spanning pipelines under four different boundary conditions, based on GITT - the generalised integral transform technique. The fluid-structure interaction model is proposed by combining a linear structural equation and a non-linear distributed wake oscillator model, which simulates the effect of external current acting on the pipeline. The eigenvalue problems for the cross-flow vibration of the free-spanning submarine pipeline conveying internal fluid for four different boundary conditions are examined. The solution method of the natural frequency based on GITT is proposed. The explicit analytical formulae for the cross-flow displacement of the pipeline free span are derived, and the mode shapes and dynamic behaviours of the pipeline free span are discussed with different boundary conditions. The methodology and results in this paper can also expand to solving even more complicated boundary-value problems.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125216096","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}
Pub Date : 2018-06-01DOI: 10.3940/RINA.IJME.2018.A2.460
S. Sindagi, R. Vijayakumar, B. K. Saxena
The reduction of ship’s resistance is one of the most effective way to reduce emissions, operating costs and to improve EEDI. It is reported that, for slow moving vessels, the frictional drag accounts for as much as 80% of the total drag, thus there is a strong demand for the reduction in the frictional drag. The use of air as a lubricant, known as Micro Bubble Drag Reduction, to reduce that frictional drag is an active research topic. The main focus of authors is to present the current scenario of research carried out worldwide along with numerical simulation of air injection in a rectangular channel. Latest developments in this field suggests that, there is a potential reduction of 80% & 30% reduction in frictional drag in case of flat plates and ships respectively. Review suggests that, MBDR depends on Gas or Air Diffusion which depends on, Bubble size distributions and coalescence and surface tension of liquid, which in turn depends on salinity of water, void fraction, location of injection points, depth of water in which bubbles are injected. Authors are of opinion that, Microbubbles affect the performance of Propeller, which in turn decides net savings in power considering power required to inject Microbubbles. Moreover, 3D numerical investigations into frictional drag reduction by microbubbles were carried out in Star CCM+ on a channel for different flow velocities, different void fraction and for different cross sections of flow at the injection point. This study is the first of its kind in which, variation of coefficient of friction both in longitudinal as well as spanwise direction were studied along with actual localised variation of void fraction at these points. From the study, it is concluded that, since it is a channel flow and as the flow is restricted in confined region, effect of air injection is limited to smaller area in spanwise direction as bubbles were not escaping in spanwise direction.
{"title":"Frictional Drag Reduction: Review and Numerical Simulation of Microbubble Drag Reduction in a Channel Flow","authors":"S. Sindagi, R. Vijayakumar, B. K. Saxena","doi":"10.3940/RINA.IJME.2018.A2.460","DOIUrl":"https://doi.org/10.3940/RINA.IJME.2018.A2.460","url":null,"abstract":"The reduction of ship’s resistance is one of the most effective way to reduce emissions, operating costs and to improve EEDI. It is reported that, for slow moving vessels, the frictional drag accounts for as much as 80% of the total drag, thus there is a strong demand for the reduction in the frictional drag. The use of air as a lubricant, known as Micro Bubble Drag Reduction, to reduce that frictional drag is an active research topic. The main focus of authors is to present the current scenario of research carried out worldwide along with numerical simulation of air injection in a rectangular channel. Latest developments in this field suggests that, there is a potential reduction of 80% & 30% reduction in frictional drag in case of flat plates and ships respectively. Review suggests that, MBDR depends on Gas or Air Diffusion which depends on, Bubble size distributions and coalescence and surface tension of liquid, which in turn depends on salinity of water, void fraction, location of injection points, depth of water in which bubbles are injected. Authors are of opinion that, Microbubbles affect the performance of Propeller, which in turn decides net savings in power considering power required to inject Microbubbles. Moreover, 3D numerical investigations into frictional drag reduction by microbubbles were carried out in Star CCM+ on a channel for different flow velocities, different void fraction and for different cross sections of flow at the injection point. This study is the first of its kind in which, variation of coefficient of friction both in longitudinal as well as spanwise direction were studied along with actual localised variation of void fraction at these points. From the study, it is concluded that, since it is a channel flow and as the flow is restricted in confined region, effect of air injection is limited to smaller area in spanwise direction as bubbles were not escaping in spanwise direction.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121555019","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}
Pub Date : 2018-06-01DOI: 10.3940/RINA.IJME.2018.A2.436
S. E. Lee, J. K. Paik
Sloshing impact loads can cause severe structural damage to cargo tanks in liquefied natural gas floating production storage offloading units (LNG-FPSOs or FLNGs). Studies of sloshing can be classified into two types, namely, hydrodynamics-related and structural mechanics-related studies. This study is a sequel to the authors’ previous studies (Paik et al. 2015; Lee et al. 2015), but is more related to issues of structural mechanics. In this study, a new method for probabilistic sloshing assessment, which has been previously developed by the authors, is briefly explained. The nonlinear impact structural response characteristics under sloshing impact loads are examined by a nonlinear finite element ANSYS/LS-DYNA method. An iso-damage curve, representing a pressure-impulse diagram, is derived for the self-supporting prismatic-shape IMO B type LNG cargo containment system of a hypothetical FLNG. The insights developed from this work can be useful for the damage-tolerant design of cargo tanks in FLNGs.
晃动冲击载荷会对液化天然气浮式生产储存卸载装置(lng - fpso或flng)的货舱造成严重的结构损坏。晃动的研究可分为两类,即流体力学相关研究和结构力学相关研究。本研究是作者之前研究的续作(Paik et al. 2015;Lee et al. 2015),但与结构力学问题更相关。在本研究中,简要解释了作者先前开发的一种新的概率晃动评估方法。采用ANSYS/LS-DYNA非线性有限元分析方法,研究了晃动冲击载荷作用下的非线性冲击结构响应特性。针对一种假设的浮式液化天然气(FLNG)的自支撑棱柱形IMO B型LNG货物安全壳系统,导出了代表压力冲量图的等损曲线。从这项工作中获得的见解可以用于flng中货舱的容损设计。
{"title":"Pressure Re-Impulse Diagram of the FLNG Tanks Under Sloshing Loads","authors":"S. E. Lee, J. K. Paik","doi":"10.3940/RINA.IJME.2018.A2.436","DOIUrl":"https://doi.org/10.3940/RINA.IJME.2018.A2.436","url":null,"abstract":"Sloshing impact loads can cause severe structural damage to cargo tanks in liquefied natural gas floating production storage offloading units (LNG-FPSOs or FLNGs). Studies of sloshing can be classified into two types, namely, hydrodynamics-related and structural mechanics-related studies. This study is a sequel to the authors’ previous studies (Paik et al. 2015; Lee et al. 2015), but is more related to issues of structural mechanics. In this study, a new method for probabilistic sloshing assessment, which has been previously developed by the authors, is briefly explained. The nonlinear impact structural response characteristics under sloshing impact loads are examined by a nonlinear finite element ANSYS/LS-DYNA method. An iso-damage curve, representing a pressure-impulse diagram, is derived for the self-supporting prismatic-shape IMO B type LNG cargo containment system of a hypothetical FLNG. The insights\u0000developed from this work can be useful for the damage-tolerant design of cargo tanks in FLNGs.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"2013 33","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114087352","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}
Pub Date : 2018-06-01DOI: 10.3940/rina.ijme.2018.a2.468
S. Rezvani, M. S. Kiasat
The approach developed in this paper applies to vibration analysis of rectangular stiffened plate coupled with fluid. It is obvious that the natural frequencies of a submerged structure are less than those of in vacuum and these are due to the effect of added mass of water to the structure. This paper focuses on the experimental, analytical and numerical solution of natural frequencies of submerged stiffened plate. The analytical solution based on the deflection equation of submerged orthotropic plate, Laplace’s equation and Rayleigh's method in vibration analysis. By used the FEM software the numerical results for natural frequencies are derived. The natural frequencies of the stiffened plate are obtained practically by using Fast Fourier Transformation functions (FFT) in experimental analysis. Experimental results demonstrate the validity of analytical and numerical solution and results.
{"title":"Analytical and Experimental Investigation on the Free Vibration of Submerged Stiffened Steel Plate","authors":"S. Rezvani, M. S. Kiasat","doi":"10.3940/rina.ijme.2018.a2.468","DOIUrl":"https://doi.org/10.3940/rina.ijme.2018.a2.468","url":null,"abstract":"The approach developed in this paper applies to vibration analysis of rectangular stiffened plate coupled with fluid. It is obvious that the natural frequencies of a submerged structure are less than those of in vacuum and these are due to the effect of added mass of water to the structure. This paper focuses on the experimental, analytical and numerical solution of natural frequencies of submerged stiffened plate. The analytical solution based on the deflection equation of submerged orthotropic plate, Laplace’s equation and Rayleigh's method in vibration analysis. By used the FEM software the numerical results for natural frequencies are derived. The natural frequencies of the stiffened plate are obtained practically by using Fast Fourier Transformation functions (FFT) in experimental analysis. Experimental results demonstrate the validity of analytical and numerical solution and results.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115962484","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}
Pub Date : 2018-06-01DOI: 10.3940/RINA.IJME.2018.A2.465
A. Balin, H. Demirel, E. Celik, F. Alarçin
The ship engine room has a structure that meets a number of needs related to administrative conditions. Even if a simple mechanical error is considered to be the addition of human errors into the complex structure of the engine room, it can lead to undetected loss. How the causes and effects of the detected faults affect the system is as important as an effective fault detection system to detect the fault and take immediate action against any possible engine failure. This study reveals the causes of problems occurring in the main engine auxiliary systems including cooling, lubricating, cooling oil and fuel systems, and the extent of these problems affecting the system. While the Decision Making Trial and Evaluation Laboratory supports to identify and analyze the error detection of auxiliary systems with respect to causal effect relation diagram, fuzzy sets deal with the uncertainty in decision-making and human judgements through the DEMATEL. Therefore, fuzzy DEMATEL approach is applied to examine the causes and the weights of the faults and their relation to each other in the auxiliary systems. When we look at the result of the proposed approach, fuel oil pump failures has more impact on the all system and air cooler problems has the second highest place among the all errors.
{"title":"A Fuzzy DEMATAL Model Proposal for the Cause and Effect of the Fault Occuring in the Auxiliary Systems of the Ships' Main Engine","authors":"A. Balin, H. Demirel, E. Celik, F. Alarçin","doi":"10.3940/RINA.IJME.2018.A2.465","DOIUrl":"https://doi.org/10.3940/RINA.IJME.2018.A2.465","url":null,"abstract":"The ship engine room has a structure that meets a number of needs related to administrative conditions. Even if a simple mechanical error is considered to be the addition of human errors into the complex structure of the engine room, it can lead to undetected loss. How the causes and effects of the detected faults affect the system is as important as an effective fault detection system to detect the fault and take immediate action against any possible engine failure. This study reveals the causes of problems occurring in the main engine auxiliary systems including cooling, lubricating, cooling oil and fuel systems, and the extent of these problems affecting the system. While the Decision Making Trial and Evaluation Laboratory supports to identify and analyze the error detection of auxiliary systems with respect to causal effect relation diagram, fuzzy sets deal with the uncertainty in decision-making and human judgements through the DEMATEL. Therefore, fuzzy DEMATEL approach is applied to examine the causes and the weights of the faults and their relation to each other in the auxiliary systems. When we look at the result of the proposed approach, fuel oil pump failures has more impact on the all system and air cooler problems has the second highest place among the all errors.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134045145","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}
Pub Date : 2018-06-01DOI: 10.3940/rina.ijme.2018.a2.427
J. Mathew, D. Sgarioto, J. Duffy, G. Macfarlane, S. Denehy, J. Norman, A. Cameron, N. Eutick, F. Walree
Hydrodynamic interactions during Replenishment at Sea (RAS) operations can lead to large ship motions and make it difficult for vessels to maintain station during the operation. A research program has been established which aims to validate numerical seakeeping tools to enable the development of enhanced operator guidance for RAS. This paper presents analysis of the first phase of scale model experiments and focuses on the influence that both the lateral and longitudinal separations between two vessels have on the interactions during RAS. The experiments are conducted in regular head seas on a Landing Helicopter Dock (LHD) and a Supply Vessel (SV) in intermediate water depth. The SV is shorter than the LHD by approximately 17%, but due to its larger block coefficient, it displaces almost 16% more than the LHD. Generally, the motions of the SV were larger than the LHD. It was found that hydrodynamic interactions can lead to large SV roll motions in head seas. Directions for future work are provided.
{"title":"An Experimental Study of Ship Motions During Replenishment at Sea Operations Between a Supply Vessel and a Landing Helicopter Dock","authors":"J. Mathew, D. Sgarioto, J. Duffy, G. Macfarlane, S. Denehy, J. Norman, A. Cameron, N. Eutick, F. Walree","doi":"10.3940/rina.ijme.2018.a2.427","DOIUrl":"https://doi.org/10.3940/rina.ijme.2018.a2.427","url":null,"abstract":"Hydrodynamic interactions during Replenishment at Sea (RAS) operations can lead to large ship motions and make it difficult for vessels to maintain station during the operation. A research program has been established which aims to validate numerical seakeeping tools to enable the development of enhanced operator guidance for RAS. This paper presents analysis of the first phase of scale model experiments and focuses on the influence that both the lateral and longitudinal separations between two vessels have on the interactions during RAS. The experiments are conducted in regular head seas on a Landing Helicopter Dock (LHD) and a Supply Vessel (SV) in intermediate water depth. The SV is shorter than the LHD by approximately 17%, but due to its larger block coefficient, it displaces almost 16% more than the LHD. Generally, the motions of the SV were larger than the LHD. It was found that hydrodynamic interactions can lead to large SV roll motions in head seas. Directions for future work are provided.","PeriodicalId":213676,"journal":{"name":"International Journal of Maritime Engineering Vol 160 2018 A2","volume":"230 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134592217","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}