Subjects -> ENVIRONMENTAL STUDIES (Total: 913 journals)
    - ENVIRONMENTAL STUDIES (810 journals)
    - POLLUTION (31 journals)
    - TOXICOLOGY AND ENVIRONMENTAL SAFETY (54 journals)
    - WASTE MANAGEMENT (18 journals)

ENVIRONMENTAL STUDIES (810 journals)            First | 1 2 3 4 5     

Showing 601 - 378 of 378 Journals sorted alphabetically
Multequina     Open Access  
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis     Hybrid Journal   (Followers: 5)
Mutation Research/Genetic Toxicology and Environmental Mutagenesis     Hybrid Journal   (Followers: 8)
Nano Select     Open Access  
Nanotechnology for Environmental Engineering     Hybrid Journal  
Nativa     Open Access  
Natur und Recht     Hybrid Journal   (Followers: 6)
Natural Areas Journal     Full-text available via subscription   (Followers: 10)
Natural Hazards     Hybrid Journal   (Followers: 53)
Natural Resources     Open Access  
Natural Resources & Engineering     Hybrid Journal  
Natural Resources and Environmental Issues     Open Access   (Followers: 2)
Nature and Culture     Full-text available via subscription   (Followers: 11)
Nature-Based Solutions     Open Access  
Nepal Journal of Environmental Science     Open Access   (Followers: 4)
NeuroToxicology     Hybrid Journal   (Followers: 1)
Neurotoxicology and Teratology     Hybrid Journal   (Followers: 3)
NEW SOLUTIONS: A Journal of Environmental and Occupational Health Policy     Full-text available via subscription   (Followers: 2)
New Zealand Journal of Environmental Law     Full-text available via subscription   (Followers: 4)
NJAS : Wageningen Journal of Life Sciences     Hybrid Journal  
Novos Cadernos NAEA     Open Access  
npj Urban Sustainability     Open Access  
Observatorio Medioambiental     Open Access  
Occupational and Environmental Medicine     Hybrid Journal   (Followers: 18)
Ochrona Srodowiska i Zasobów Naturalnych : Environmental Protection and Natural Resources     Open Access  
Oecologia     Hybrid Journal   (Followers: 54)
Oikos     Hybrid Journal   (Followers: 55)
One Earth     Hybrid Journal   (Followers: 2)
One Ecosystem     Open Access  
Open Environmental Research Journal     Open Access   (Followers: 1)
Open Journal of Marine Science     Open Access   (Followers: 6)
Open Journal of Modern Hydrology     Open Access   (Followers: 5)
Our Nature     Open Access   (Followers: 1)
Pace Environmental Law Review     Open Access   (Followers: 4)
Packaging, Transport, Storage & Security of Radioactive Material     Hybrid Journal   (Followers: 2)
Palaeobiodiversity and Palaeoenvironments     Hybrid Journal   (Followers: 3)
Particle and Fibre Toxicology     Open Access   (Followers: 2)
Pastos y Forrajes     Open Access  
Peer Community Journal     Open Access   (Followers: 8)
Perspectives in Ecology and Conservation     Full-text available via subscription   (Followers: 5)
Pharmacology & Therapeutics     Hybrid Journal   (Followers: 3)
Pharmacology Biochemistry and Behavior     Hybrid Journal   (Followers: 2)
Physio-Géo     Open Access   (Followers: 1)
Pittsburgh Journal of Environmental and Public Health Law     Open Access  
Planet     Open Access   (Followers: 4)
Planeta Amazônia : Revista Internacional de Direito Ambiental e Políticas Públicas     Open Access  
Planning & Environmental Law: Issues and decisions that impact the built and natural environments     Hybrid Journal   (Followers: 6)
Plant Ecology & Diversity     Partially Free   (Followers: 13)
Plant Knowledge Journal     Open Access   (Followers: 1)
Plant, Cell & Environment     Hybrid Journal   (Followers: 8)
Plant-Environment Interactions     Open Access  
Plants, People, Planet     Open Access   (Followers: 1)
Polar Journal     Hybrid Journal   (Followers: 2)
Political Studies     Hybrid Journal   (Followers: 42)
Political Studies Review     Hybrid Journal   (Followers: 18)
Population and Environment     Hybrid Journal   (Followers: 6)
Population Ecology     Hybrid Journal   (Followers: 12)
Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management     Full-text available via subscription  
Presence: Virtual and Augmented Reality     Hybrid Journal   (Followers: 2)
Proceedings of the Institution of Civil Engineers - Waste and Resource Management     Hybrid Journal   (Followers: 1)
Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment     Hybrid Journal   (Followers: 3)
Proceedings of the International Academy of Ecology and Environmental Sciences     Open Access   (Followers: 1)
Proceedings of the Vertebrate Pest Conference     Open Access  
Process Integration and Optimization for Sustainability     Hybrid Journal  
Process Safety and Environmental Protection     Hybrid Journal   (Followers: 4)
Producción + Limpia     Open Access  
Progress in Disaster Science     Open Access   (Followers: 1)
Progress in Industrial Ecology, An International Journal     Hybrid Journal   (Followers: 2)
Projets de Paysage     Open Access  
Psychological Assessment     Full-text available via subscription   (Followers: 12)
Public Money & Management     Hybrid Journal   (Followers: 7)
Quaternary     Open Access  
Recursos Rurais     Open Access  
REDER : Revista de Estudios Latinoamericanos sobre Reducción del Riesgo de Desastres     Open Access  
Regional Environmental Change     Open Access   (Followers: 2)
Regional Sustainability     Open Access   (Followers: 1)
Rekayasa     Open Access  
Remediation Journal     Hybrid Journal   (Followers: 8)
Remote Sensing Applications : Society and Environment     Full-text available via subscription   (Followers: 9)
Remote Sensing Letters     Hybrid Journal   (Followers: 46)
Rendiconti Lincei     Hybrid Journal  
Renewable Energy and Environmental Sustainability     Open Access   (Followers: 1)
Renewable Energy Focus     Full-text available via subscription   (Followers: 7)
Research & Reviews : Journal of Ecology     Full-text available via subscription   (Followers: 3)
Research and Practice for Persons with Severe Disabilities     Full-text available via subscription   (Followers: 3)
Research Journal of Environmental Sciences     Open Access   (Followers: 2)
Research Journal of Environmental Toxicology     Open Access   (Followers: 2)
Resources     Open Access  
Resources and Environment     Open Access  
Resources, Conservation & Recycling     Hybrid Journal   (Followers: 20)
Resources, Conservation & Recycling : X     Open Access   (Followers: 1)
Resources, Conservation & Recycling Advances     Open Access   (Followers: 1)
Rethinking Ecology     Open Access  
Reuse/Recycle Newsletter     Hybrid Journal  
Review of Agricultural, Food and Environmental Studies     Hybrid Journal  
Review of Environmental Economics and Policy     Hybrid Journal   (Followers: 11)
Revista AIDIS de Ingeniería y Ciencias Ambientales. Investigación, desarrollo y práctica     Open Access  
Revista Ambivalências     Open Access  
Revista Brasileira de Ciências Ambientais     Open Access   (Followers: 1)
Revista Brasileira de Meio Ambiente     Open Access  
Revista Chapingo. Serie Ciencias Forestales y del Ambiente     Open Access  
Revista Ciência, Tecnologia & Ambiente     Open Access  
Revista de Ciencias Ambientales     Open Access  
Revista de Direito Ambiental e Socioambientalismo     Open Access  
Revista de Direito e Sustentabilidade     Open Access  
Revista de Gestão Ambiental e Sustentabilidade - GeAS     Open Access  
Revista de Investigación en Agroproducción Sustentable     Open Access  
Revista de Salud Ambiental     Open Access  
Revista ECOVIDA     Open Access   (Followers: 4)
Revista Eletrônica de Gestão e Tecnologias Ambientais     Open Access  
Revista Geama     Open Access  
Revista Hábitat Sustenable     Open Access  
Revista Iberoamericana Ambiente & Sustentabilidad     Open Access  
Revista Kawsaypacha: Sociedad y Medio Ambiente     Open Access  
Revista Laborativa     Open Access  
Revista Meio Ambiente e Sustentabilidade     Open Access  
Revista Mundi Meio Ambiente e Agrárias     Open Access  
Revista Verde de Agroecologia e Desenvolvimento Sustentável     Open Access   (Followers: 2)
Rivista di Studi sulla Sostenibilità     Full-text available via subscription   (Followers: 1)
RUDN Journal of Ecology and Life Safety     Open Access  
Russian Journal of Ecology     Hybrid Journal   (Followers: 1)
Safety Science     Hybrid Journal   (Followers: 28)
San Francisco Estuary and Watershed Science     Open Access  
SAR and QSAR in Environmental Research     Hybrid Journal   (Followers: 1)
Saúde e Meio Ambiente : Revista Interdisciplinar     Open Access  
Scandinavian Journal of Work, Environment & Health     Partially Free   (Followers: 13)
Science of The Total Environment     Hybrid Journal   (Followers: 37)
Sciences Eaux & Territoires : la Revue du Cemagref     Open Access  
Social and Environmental Accountability Journal     Hybrid Journal   (Followers: 3)
Sociedad y Ambiente     Open Access  
Soil and Sediment Contamination: An International Journal     Hybrid Journal   (Followers: 3)
Soil and Tillage Research     Hybrid Journal   (Followers: 9)
South Australian Geographical Journal     Open Access  
South Pacific Journal of Natural and Applied Sciences     Hybrid Journal  
Southern African Journal of Environmental Education     Open Access  
Southern Forests : a Journal of Forest Science     Hybrid Journal   (Followers: 3)
Sriwijaya Journal of Environment     Open Access  
Stochastic Environmental Research and Risk Assessment     Hybrid Journal   (Followers: 4)
Strategic Planning for Energy and the Environment     Hybrid Journal   (Followers: 4)
Studies in Conservation     Hybrid Journal   (Followers: 16)
Sustainability     Open Access   (Followers: 21)
Sustainability Agri Food and Environmental Research     Open Access   (Followers: 4)
Sustainability in Environment     Open Access   (Followers: 2)
Sustainable and Resilient Infrastructure     Hybrid Journal  
Sustainable Cities and Society     Hybrid Journal   (Followers: 22)
Sustainable Development     Hybrid Journal   (Followers: 14)
Sustainable Development Law & Policy     Open Access   (Followers: 12)
Sustainable Development Strategy and Practise     Open Access   (Followers: 4)
Sustainable Horizons     Full-text available via subscription   (Followers: 6)
Sustainable Technology and Entrepreneurship     Full-text available via subscription   (Followers: 8)
Sustinere : Journal of Environment and Sustainability     Open Access  
TECHNE - Journal of Technology for Architecture and Environment     Open Access   (Followers: 11)
Tecnogestión     Open Access  
Territorio della Ricerca su Insediamenti e Ambiente. Rivista internazionale di cultura urbanistica     Open Access  
The Historic Environment : Policy & Practice     Hybrid Journal   (Followers: 4)
The International Journal on Media Management     Hybrid Journal   (Followers: 7)
The Ring     Open Access  
Theoretical Ecology     Hybrid Journal   (Followers: 15)
Toxicologic Pathology     Hybrid Journal   (Followers: 18)
Toxicological & Environmental Chemistry     Hybrid Journal   (Followers: 2)
Toxicological Sciences     Hybrid Journal   (Followers: 11)
Toxicology     Hybrid Journal   (Followers: 18)
Toxicology and Applied Pharmacology     Hybrid Journal   (Followers: 24)
Toxicology and Industrial Health     Hybrid Journal   (Followers: 6)
Toxicology in Vitro     Hybrid Journal   (Followers: 11)
Toxicology Letters     Hybrid Journal   (Followers: 15)
Toxicology Mechanisms and Methods     Hybrid Journal   (Followers: 7)
Toxicon     Hybrid Journal   (Followers: 5)
Toxicon : X     Open Access  
Toxin Reviews     Hybrid Journal  
Transactions on Environment and Electrical Engineering     Open Access  
Transportation Research Part D: Transport and Environment     Hybrid Journal   (Followers: 28)
Transportation Safety and Environment     Open Access   (Followers: 1)
Transylvanian Review of Systematical and Ecological Research     Open Access  
Trends in Ecology & Evolution     Full-text available via subscription   (Followers: 242)
Trends in Environmental Analytical Chemistry     Hybrid Journal   (Followers: 3)
Trends in Pharmacological Sciences     Full-text available via subscription   (Followers: 19)
Tropicultura     Open Access  
Turkish Journal of Engineering and Environmental Sciences     Open Access   (Followers: 1)
UCLA Journal of Environmental Law and Policy     Open Access   (Followers: 1)
UD y la Geomática     Open Access  
Universidad y Ciencia     Open Access  
Universidad y Ciencia     Open Access  
UNM Environmental Journals     Open Access  
Urban Studies     Hybrid Journal   (Followers: 69)
Urban Transformations     Open Access  
Veredas do Direito : Direito Ambiental e Desenvolvimento Sustentável     Open Access  
VertigO - la revue électronique en sciences de l’environnement     Open Access   (Followers: 1)
Villanova Environmental Law Journal     Open Access  
Waste Management & Research     Hybrid Journal   (Followers: 6)
Water Conservation Science and Engineering     Hybrid Journal   (Followers: 1)
Water Environment Research     Full-text available via subscription   (Followers: 43)
Water International     Hybrid Journal   (Followers: 19)
Water Security     Hybrid Journal   (Followers: 6)
Water, Air, & Soil Pollution : Focus     Hybrid Journal   (Followers: 7)
Water, Air, & Soil Pollution     Open Access   (Followers: 21)
Weather and Forecasting     Hybrid Journal   (Followers: 43)
Weather, Climate, and Society     Hybrid Journal   (Followers: 16)
Web Ecology     Open Access   (Followers: 3)
Wetlands     Hybrid Journal   (Followers: 25)

  First | 1 2 3 4 5     

Similar Journals
Journal Cover
Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment
Journal Prestige (SJR): 0.618
Citation Impact (citeScore): 2
Number of Followers: 3  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1475-0902 - ISSN (Online) 2041-3084
Published by Sage Publications Homepage  [1174 journals]
  • Weak thruster fault detection for AUV based on Bayesian network and Hidden
           Markov model

    • Free pre-print version: Loading...

      Authors: Feng Yao, Zeyu Chen, Xing Liu, Mingjun Zhang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Weak thruster fault detection problem is investigated for Autonomous Underwater Vehicle (AUV) with being less than 10% loss of effectiveness fault in a thruster. For the weak thruster fault, the fault features are small in general, meanwhile the fault features are also difficult to be distinguished from the external disturbances including measurement noise. In this paper, a weak thruster fault detection method is developed based on Bayesian network and hidden Markov model. In the proposed method, the fault features are enhanced at first and then the fault detection is achieved based on the occurrence probability. Specifically, Bayesian network is applicable to enhance weak signals, but the prior knowledge is difficult to obtain for an AUV. To solve this problem, this paper introduces sparse decomposition into Bayesian network to enhance the weak thruster fault features. And then, a hidden Markov model is established to provide the likelihood probability between the observation sequence and the predict one. The fault detection is achieved according to comparing the probability and the threshold. Finally, pool-experimental results on an AUV are presented to verify the effectiveness of the developed fault detection method.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-06-23T09:57:04Z
      DOI: 10.1177/14750902221101798
       
  • The hydrodynamic analysis of multiple hydrofoils translating in tandem in
           presence of a free surface

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      Authors: Nutan Kumari, Arnab Chakraborty, Suneela Jangam
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Hydrofoils find its presence in various engineering applications including high speed marine crafts, blades of hydro-kinetic turbines etc. So, depending on the type of marine application, the foils are arranged in different complex arrangements (i.e. in line, or in tandem) that can alter flow dynamics of the working fluid flowing around them. In order to design efficient marine propulsion systems, it is important to study the effect of different arrangements of hydrofoil systems on its hydrodynamic characteristics (lift, drag, pressure coefficient, velocity contour, etc). In this study, the numerical simulation of fluid flow over a tandem hydrofoils is carried out in presence of a free surface. The present study is limited for a constant Reynolds number of 166,784.8, and at a Froude number of 0.57. The unsteady RANS equations are solved using the volume of fluid (VOF) method embedded in commercial software STAR-CCM+ incorporating [math] turbulence model. The first part of the study focuses on varying spacing ratios (l/c) that range from 0.1 to 4. In the second part of the study, the angle of attack of the downstream hydrofoil was varied over zero degrees to stall keeping the upstream hydrofoil at a zero degree angle of attack. For both studies, pressure and velocity distributions, lift as well as drag coefficients were evaluated. It is concluded that the presence of a free surface in a close proximity to the foils, different spacing between the hydrofoils, and varying angle of attacks of the downstream hydrofoil have significant effects on the overall performance.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-06-23T05:21:06Z
      DOI: 10.1177/14750902221103323
       
  • Evaluation of various fuel alternatives in terms of sustainability for the
           ship investment decision using single valued neutrosophic numbers with
           TOPSIS methods

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      Authors: Mahmut Mollaoglu, Umur Bucak, Hakan Demirel, Abit Balin
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      IMO has introduced regulations to improve fuel quality in the sector to reduce emissions from ships carrying the vast majority of world trade. As a result of these regulations, which were planned gradually, carbon-neutral shipping was targeted. In line with this goal, it was seen that ship operating companies tend to various alternatives to increase fuel quality. This study evaluated various fuel alternatives for ship investment decisions by employing the Technique for Order Preference By Similarity to Ideal Solution (TOPSIS) method under the Single Valued Neutrosophic Sets (SVNS) in terms of sustainability aspects. First, criteria that are specific to the ship investment decision under the aspects of sustainability and their weights were determined. Then, these weights were placed in the model to determine the most sustainable ship fuel produced within the scope of the study. Finally, alternatives determined in terms of fuel type, which is one of the items to be decided on ship investment, were listed according to their degree of sustainability. According to the findings, dual fuel and bio-fuel were selected as more sustainable bunker fuels for today. Technically, findings were evaluated, and the pros and cons of the related bunker fuels were revealed. In the light of the findings, evaluations were made on alternatives.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-06-21T01:08:02Z
      DOI: 10.1177/14750902221103433
       
  • Experimental study of the effects of Vee-shaped steps on the hydrodynamic
           performance of planing hulls

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      Authors: Parviz Ghadimi, Sayyed Mahdi Sajedi, Mohammad Sheikholeslami
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Speed and stability are two essential criteria for assessment of planing hull performance. Accordingly, the effects of step shape on these vessels’ hydrodynamic performance and stability are experimentally investigated. Five different models are studied which are based on a high-speed recreational craft and are primarily the same in form and dimensions. One of these models does not have a step, two of them have transverse steps, and two other models have Vee-shaped steps. These five models all have a length of 2.64 m, a beam of 0.55 m, a deadrise angle of 24°, and weigh 86 kg. As the parent model, that is, the non-stepped model is unstable at high speeds, this study is aimed to figure out how different types of steps could prevent this kind of instability. The trim angle, resistance, and lengths of the wetted keel and wetted chine of all these models are reported at beam Froude numbers ranging from 0.43 to 3.44. First, the non-step model is investigated in towing tank tests. The optimum position for the center of gravity of this model is determined to be at a distance of 30% of the model’s length to the transom, which leads to the lowest resistance while the model still remains stable. The models with the aft-wise Vee type and fore-wise Vee type experience the lowest and highest resistance among all studied models, respectively. The steps’ performance appears to be directly related to the ventilation condition at the bottom of stepped models. It is also observed that aft-wise Vee-shaped step leads to the most severe flow separation, and the model with this type of step has the least wetted surface area compared to other studied models.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-06-10T11:40:07Z
      DOI: 10.1177/14750902221098304
       
  • Evaluation of critical problems of heavy fuel oil separators on ships by
           best-worst method

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      Authors: Veysi Başhan, Hakan Demirel, Erkan Celik
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      It is known that trade by ship is a cheaper way than airway, land, and rail trade. One of the most important reasons for this is that ships use heavy fuel oil (HFO), which is cheap but also poor quality fuel. This HFO used in ships needs to be cleaned with machines called separators (purifiers). Therefore, the separator is one of the vital auxiliary machines on the ship. A satisfactory separation should be done in order to get rid of the effects such as water in the fuel, sludge formation, pump ability, mixing of different grades in the tanks, abrasion, and corrosion, which are the most important risks in the burning of fuel oil. Many problems are encountered while trying to make good separation. Therefore, in this article, 20 important problems that are frequently encountered in ship HFO separators are evaluated with the best-worst method (BWM) by consulting marine experts. Results show that dirty separator discs (also fractured or broken), wrong gravity disc choice (or bad interface position), and unsatisfactory bowl work are the most important problems among 20 critical and frequent separator problems. Problems and results are very important in terms of smooth ship machinery operations and we think that this study will close this gap in the literature by ordering and identifying problems and also solution recommendations.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-06-08T01:57:19Z
      DOI: 10.1177/14750902221097268
       
  • Mechanics of drag reduction of an axisymmetric body of revolution with
           shallow dimples

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      Authors: J P Panda, J Handique, H V Warrior
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      In this article, the mechanics of drag reduction on an axisymmetric body of revolution by shallow dimples is presented by using the high-fidelity Reynolds Stress Modeling based simulations. Experimental results of drag evolution from published literature at different Reynolds numbers are used to validate the model predictions. The numerical predictions show good agreement with the experimental results. It is observed that the drag of the body is reduced by a maximum of [math] with such shape modification (for the depth to diameter ratio of [math] and coverage ratio of [math]). This arises due to the reduced level of turbulence, flow stabilization and suppression of flow separation in the boundary layer of the body. From the analysis of turbulence states in the anisotopic invariant map (AIM) for the case of the dimpled body, we show that the turbulence reaches an axisymmetric limit in the layers close to the surface of the body. There is also a reduced misalignment between the mean flow direction and principal axis of the Reynolds stress tensor, which results in such drag reduction. The dimple depth to diameter(s/d) and coverage ratio (a/A) are also varied to evaluate its effect on drag evolution. An empirical correlation for the drag coefficient is also developed by using polynomial regression in terms of the different shape and flow parameters, for example, s/d ratio, a/A ratio, and Reynolds shear stress.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-06-06T08:46:26Z
      DOI: 10.1177/14750902221100114
       
  • Marine environment numerical simulation of morphological planning of land
           reclamation

    • Free pre-print version: Loading...

      Authors: He Zhang, Yantong Li, Wei Jiang, Rui Wang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Based on the evaluation criteria of the impact of different types of reclamation design on the natural environment of coastal waters, the environmental fluid dynamics model was used to simulate the seawater environment in 13 scenarios from three aspects: the shape of the artificial island, the size of inner lake outlet and the layout of the artificial island. The hydrodynamic force and water exchange capacity of these islands were quantitatively compared, and the effects of different artificial islands on the Marine environment were summarized. The planning morphology design guidelines are summarized in four aspects: (1) reduce the serrated steep slope shoreline, avoid forming semi-closed water, and increase the simple and smooth shoreline; (2) reduce the width of the lake mouth to increase the length of the lake; (3) choose a simple alignment parallel to the shore; (4) the design mainly focuses on the morphology of shoreline, followed by consideration of the lake mouth and artificial island arrangement.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-25T11:40:32Z
      DOI: 10.1177/14750902221079478
       
  • An object detection and classification method for underwater visual images
           based on the bag-of-words model

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      Authors: Tianchi Zhang, Qian Li, Xing Liu
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      In this study, an autonomous underwater vehicle (AUV) detection technique was used as the background to investigate the target classification method for underwater visual images. The target classification method is based on the bag-of-words model, with reduced classification accuracy when the edges of underwater objects are blurred, and when there are many noise points. To solve this problem, an improved visual dictionary generation method was proposed based on the bag-of-words model. The proposed method includes a step on decomposing the complete contour of the target before extracting the features. The DCE (discrete contour evolution) algorithm was used to decompose the complete contour into segments of different lengths, and the SC (shape context) method was applied to extract the features of the contour segments. The FCM (Fuzzy C-Means) algorithm was then used to generate a visual dictionary. To address the classification accuracy problem that causes the underwater targets to decrease after adding spatial location information to the bag-of-words model instead of increasing, an improved spatial location information description method was proposed. The contour segments with the nearest-neighbor relationship were represented as visual phrases, constituting the spatial information of the bag-of-words model. Additionally, for the problem of the shape information of contour segments with different shapes, and the relative position information between the contour segments having different contributions to the target classification, a method was developed to balance the contributions of the two using the optimal weight selected from the experiments. The experimental results demonstrated that the proposed method can effectively improve the classification accuracy of underwater target images.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-21T09:57:17Z
      DOI: 10.1177/14750902221096984
       
  • Feasibility of elastomeric composites as alternative materials for marine
           applications: A compendious review on their properties and opportunities

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      Authors: D Aravind, K Senthilkumar, N Rajini, T Senthil Muthu Kumar, M Chandrasekar, Sikiru O Ismail, Rungsima Yeetsorn, Jyotishkumar Parameswaranpillai, Suchart Siengchin, MP Indira Devi
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The term elastomer is a curtailment of two words, which are elastic and polymers. Accordingly, elastomers are polymer materials with elasticity. The significant challenges hindering the development of materials for naval applications, similar to other engineering sectors, include achieving a competitive light elastomeric structure. Marine structures are susceptible to various damage responses due to various loads throughout their service life. Being flexible, elastomer has a low modulus of elasticity, exhibits higher values of failure strain and yield strength. In these regards, elastomers are attractive materials for applications that require elasticity because they offer substantial advantages compared to traditional materials. However, the low fire resistance of these elastomeric materials jeopardizes their use in some critical applications. As a result, elastomeric blends and composites containing flame retardant (FR) additives are commonly used. On the other hand, elastomers possess (i) high strength-to-weight ratio, (ii) excellent impact properties, (iii) low infrared, magnetic, and radar signatures, (iv) excellent durability, and (v) high resilience to extreme loads. Hence, the scope of this study focuses on review and awareness regarding the feasibility of marine applications of elastomers/elastomeric composites, their current scientific and technological drawbacks, and future outlooks or prospects to support several applications in the marine industry.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-19T05:39:48Z
      DOI: 10.1177/14750902221095321
       
  • A systematic literature review and future insights on maritime and
           offshore human reliability analysis

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      Authors: Cagatay Kandemir, Metin Celik
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This paper conducts a systematic literature review through human reliability studies in maritime and offshore industries particularly. The review deeply focussed on the number of 219 featured studies. Among them, 25 special papers were reviewed in detail to have a closer insight into the maritime offshore domain. The proposed maritime HRA concepts and methodologies in the past studies have been inspected and presented with various statistical data. Clustering the existing progress in the literature and industry levels, the effects of emerging industrial developments on human reliability investigations are extensively discussed. Considering the future maritime initiatives (i.e. MASS Code, SDGs, Maritime & Offshore Digitalisation, SkillsFuture, etc.), the paper introduced a new R&D concept entitled Maritime & Offshore Human Reliability Research 2.0 (MOHR 2.0). The MOHR 2.0 is clarified the new contributing dimensions to redefine the tasks and operating environment to conduct next-generation human reliability analysis. Particularly, an application protocol is provided to extend the studies towards offshore operations. Consequently, this study contributes to understanding the potential of existing human reliability studies in maritime and offshore operations while further insights, opportunities, and challenges are highlighted.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-18T07:10:19Z
      DOI: 10.1177/14750902221098308
       
  • Blade attachment degree classification for marine current turbines using
           AGMF-DFA under instantaneous variable current speed

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      Authors: Chao Yang, Tao Xie, Tianzhen Wang, Yide Wang, Dongxu Jia
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Marine current turbine (MCT) blades are continuously exposed to seawater, making them extremely susceptible to marine biological attachment and causing MCT blade imbalance fault. It is challenging to extract attachment features with the instantaneous variable current speed. In fact, the collected signal is highly nonlinear and nonstationary, which involves different scales and dimensions affected by the instantaneous current speed. In this paper, improved multifractal detrended fluctuation analysis (MF-DFA) is adopted to analyze such signals. The original MF-DFA is easily affected by the order of the fitting polynomial and cannot achieve the desired adaptive effect. The paper combines grey relation analysis and ensemble empirical mode decomposition (EEMD) to adaptively select the detrended function. The proposed adaptive grey MF-DFA (AGMF-DFA) method is validated with data collected from a testbed composed of an MCT coupled to a 230W permanent magnet synchronous generator. The result shows that the proposed method is effective for the attachment degree classification under the instantaneous variable current speed.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-17T09:40:21Z
      DOI: 10.1177/14750902221087772
       
  • Resilient sliding mode control of multiple autonomous underwater vehicles
           under stochastic DoS attack

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      Authors: Zehua Ye, Ying Xu, Jia-Hao Dong, Juntong Chen, Dan Zhang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This paper is concerned with the security sliding mode-based leader-following control of multiple autonomous unmanned underwater vehicles (AUVs) system subject to stochastic DoS attacks. Firstly, a Bernoulli variable is used to describe the phenomenon of stochastic DoS attacks between controllers and actuators, and the attack probability is known for controller design. Secondly, the closed-loop system is established by taking the integral sliding mode control scheme and stochastic DoS attacks into account. Then, the conditions of stochastic stability for system are given by using the stochastic systems analysis method and the model decomposition technique. In the simulation part, a group of AUVs models is used to verify the validity of the proposed state consensus control scheme. The simulation example shows that all the state can achieve consensus even in presence of randomly launched DoS attack.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-12T10:23:42Z
      DOI: 10.1177/14750902221096538
       
  • Research on fault prediction of marine diesel engine based on
           attention-LSTM

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      Authors: Yi Liu, Huibing Gan, Yujin Cong, Guotong Hu
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The marine diesel engine is an important guarantee for the safe operation of the ship. It is of great significance to predict the running trend of the diesel engine and infer whether the diesel engine is in an abnormal working state in advance to ensure the safe operation of the ship. In this paper, combining the feature extraction ability of the attention mechanism (Attention) and the time-series memory ability of the long short-term neural network (LSTM), a prediction model of the exhaust gas temperature of the marine diesel engine is constructed. Meanwhile, in order to improve the prediction accuracy of the model, the improved particle swarm algorithm is used to optimize the structural parameters of the model, and a model with higher prediction performance is obtained. Then, according to the residual value distribution between the predicted value and the actual value of the model, the process control method is used to set the fault threshold, and the experimental data of normal and abnormal conditions are used for verification. The results show that the proposed model can accurately predict developing failures and provide a new method for ship condition maintenance.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-12T10:21:42Z
      DOI: 10.1177/14750902221096221
       
  • Wave-induced seepage force on a buried pipe in the presence of a floating
           structure

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      Authors: Duggivalasa Suresh Kumar, Vijay Gopikrishnan Kasala, Dasharatha Achani, Mohammed Rabius Sunny, Trilochan Sahoo
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This work aims to understand the variations in the oscillatory seepage force on a buried pipe in the presence of a floating structure under the influence of long-crested waves. The study is based on numerical investigation carried out using Finite Element Analysis wherein the water wave is modelled using potential flow theory and the soil modelling in accordance with Biot’s consolidation equations. The investigation is carried out in the frequency domain considering a range of wave, soil and floating body parameters. At first, the sensitivity of wave and soil parameters on the development of vertical seepage force on a buried pipe is studied. Then a floating body is introduced to the fluid domain and the wave scattering effects on the seabed pressures and seepage forces on the buried pipe are investigated. The numerical results reveal that in the case of barge or floating-fixed breakwater, the increase in vertical seepage forces on the buried pipe is about two-fold in intermediate water depths (π/8 
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-12T10:19:27Z
      DOI: 10.1177/14750902221096019
       
  • A fault diagnosis method for underwater thruster based on RFR-SVM

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      Authors: Zhenzhong Chu, Zhiqiang Li, Zhenhao Gu, Yunsai Chen, Mingjun Zhang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      A fault diagnosis method for underwater thruster based on Random Forest Regression (RFR) and Support Vector Machine (SVM) is proposed in this paper. Aiming at the problem of insufficient fault diagnosis accuracy caused by the extremely unbalanced scale of normal samples and fault samples, a data argumentation method of fault samples based on RFR is proposed. Considering the over-fitting phenomenon of machine learning in the case of small samples, tsfresh package, and kernel principal component analysis (KPCA) are used to extract features from thruster time series data, and then the SVM is used to train the thruster fault diagnosis model. Finally, the effectiveness of the proposed method is verified by experiment in a pool environment.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-05-09T08:00:41Z
      DOI: 10.1177/14750902221095423
       
  • Experimental study of wave force on breakwater head under oblique waves

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      Authors: Xinyu Han, Sheng Dong
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The head of a breakwater warrants special consideration to achieve the necessary stability at vulnerable part of its structure. To widen the entrance to a harbour, a caisson is used for the breakwater head. Therefore, the wave force on the caisson head under oblique waves was analysed in this study. Physical model tests were performed in a wave tank, where wave loads on two weathering sections (S1 and S2) of the caisson head were measured under oblique-regular and irregular wave attacks. The results have shown that the improved Goda’s method can predict the wave forces on the caisson head. The wave forces on the two sections increased with an increase in the period under different incident angles. The phase lag between the horizontal forces on S1 and S2 was evidently influenced by the incident angle. The relationship between the maximum wave force on one section and its accompanying wave force on another section was described, and the results have demonstrated that under the same incident angle, as the period increased, the maximum wave force of S1/S2 is gradually equal to its accompany wave force of another section.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-29T11:08:31Z
      DOI: 10.1177/14750902221094978
       
  • Hydrodynamic optimization of a high-speed vessel by means of
           simulation-based design methodology

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      Authors: Hasan Timurlek, Bekir Şener
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This study presents a simulation-based optimization procedure of a high-speed vessel. The presented procedure is applied on benchmark form Model 5365, a 1/8.25 scale model of the transom-stern, high-speed research vessel, R/V Athena. The procedure integrates parametric model generation, viscous numeric resistance analysis, and genetic algorithm evaluation. CAESES, a unique simulation-based design platform, is used to collect the process under one roof and handle the process automatically. The fully-parametric form is constructed by means of main characteristic curves, control curves, and various parameters to achieve quick-variation of hull forms. The numeric resistance analysis are performed via viscous flow solver and the calm-water total resistance force is defined as the optimization objective. The NSGA-II algorithm is used for evaluation of analysis results and regeneration of form variants, to achieve total resistance minimization. The optimization results show that the optimized hull form has lower resistance than Model 5365 form; a form variant with 2.02% total resistance reduction was obtained.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-26T11:01:07Z
      DOI: 10.1177/14750902221091345
       
  • Research on a novel maritime emergency search system

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      Authors: Mingzhang Chen, Xinfei Zhangchen, Xiaoshuang Xiong, Xunchen Liu, Xuancheng Zhang, Zeming Wang, Gailin Han
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      With the continuous development of the marine economy and the inland river transport, traditional vessels supervision methods have the shortcomings of short supervision range, small supervision scope, and high cost, which make it difficult to meet the requirements of modern maritime supervision. This paper proposes a novel maritime emergency search system based on unmanned aerial vehicle (UAV) and its landing platform. The system takes the base station with the cruise UAV, as the base point. Subsequently, TDMA system networking technology and wireless bridge communication technology are used to set up a local area network. Then, the improved three-dimensional raster processing is used to search the target waters. After that, several algorithms such as area optimization based on image filtering are applied to classify, integrate, and fit the waters. In addition, the base station distribution scheme and the emergency equipment intelligent management system software are designed to achieve more efficient and convenient management of the system. The system realizes unmanned, visualized, and normalized monitoring and management of the target waters through the coupling of UAV, aerial protection base stations and control terminals, and provides more detailed and accurate information for the development of search and rescue work.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-25T06:10:54Z
      DOI: 10.1177/14750902221086706
       
  • Research on wave suppression mechanism of porous baffle based on vortex
           dynamics

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      Authors: Minmin Shen, Chuanbin Sun, Baohong Tong, Xiaolei Hu
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The exciting force generated by the violent sloshing of the fluid in the tank will damage the tank structure and even affect the attitude stability of a vehicle. Hence, this study constructs a numerical model and horizontal excitation experimental platform. Taking the porous baffle in the tank of a specific type of tanker as an example, the current study analyses the impact pressure response law at different frequencies. On the basis of vortex dynamics, this work explores the evolution mechanism of the vortex flow structure under different excitation amplitudes and frequencies. The exploration reveals the law of dimensionless vortex intensity and energy change. In addition, the relationship between vortex intensity and wall pressure is determined. Studies have shown that the non-linear violent sloshing causes the resonance frequency of the tank to deviate from the natural frequency. When the excitation amplitude intensifies, the range and strength of the vortex structure and the distance from the vortex core to the baffle increase. In such circumstance, the accumulation and dissipation of energy are more evident. In addition, when the excitation frequency is closer to the resonance frequency, the distance between the vortex core and the baffle widens. Moreover, the energy intensity around the baffle increases as the frequency increases. The time history of wall pressure P and vortex intensity Q shows a certain regularity, and the ratio of Pmax to Qmax decreases with the increase of the excitation frequency.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-21T09:40:24Z
      DOI: 10.1177/14750902221089490
       
  • Water entry dynamic analysis of lightweight sandwich plates with lattice
           core: A semi-analytical approach and comparative study

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      Authors: Hao Wang, Lin Gan
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This is the third part of water entry hydro-elastic analysis of clamped sandwich plates with lattice core (CSPLC). In the first and second parts analysis, the engineering prediction model is built to estimate the dynamic responses of CSPLC. To discuss the responses of CSPLC in more detail, the objective of the present work is to investigate the hydro-elastic responses of rectangular, clamped sandwich plates with lattice core (CSPLC) subjected to water entry via combined a novel semi-analytical approach and multi-physical numerical simulation. In the theoretical approach, the hydro-elastic characteristics are quantified by coupling a hydrodynamic water entry model with a first shear displacement model of elasticity for CSPLC. The fluid-structure interaction (FSI) effects of water entry are taken into account by dividing the total impact pressure into the rigid water entry pressure and the interacting pressure. To capture the precise responses of CSPLC, both the global displacement field and the local displacement field are considered in the analytical model. The dynamic governing equations are derived from the energy variation principle and solved by employing the modal approach. Furthermore, the 3D FSI finite element simulation is carried out to get the detailed hydro-elastic characteristics of CSPLC. This engineering semi-analytical model is found to yield accurate results for dynamic responses and offers significant savings in computational cost compared to the FSI simulations. As a comparative study, for a same geometrical stiffened panel, the FSI impact pressure and structural deflection are also given respectively.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-21T09:37:49Z
      DOI: 10.1177/14750902221087798
       
  • Codesign of dynamic collision avoidance and trajectory tracking for
           autonomous surface vessels with nonlinear model predictive control

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      Authors: Jian Zheng, Jiayin Hu, Yun Li
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      In this paper, a predictive control scheme for dynamic collision avoidance and formation trajectory tracking of autonomous surface vessels (ASVs) was designed. First, a trajectory-tracking nonlinear controller for ASVs was developed in the framework of model predictive control (MPC). Next, to realize leader-follower formation control, a graph topology approach was proposed to maintain a balanced distance between the leader and followers. Then, a set of nonlinear dynamic collision avoidance constraints based on the time to closest point of approach (TCPA) and distance to closest point of approach (DCPA) models was applied as control constraints. Specifically, the ship collision risk index (CRI) was proposed as a collision avoidance constraint for the controller. Simulation studies with various collision avoidance scenarios and predictive horizons were conducted using the dynamic CyberShip II model. The simulation results demonstrate the effectiveness of the proposed codesign scheme for formation tracking control and dynamic collision avoidance. Additionally, the simulation results show that the calculation time of the system was greatly reduced when using a trigger function, with an average calculation time of approximately 0.251 s.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-15T06:37:27Z
      DOI: 10.1177/14750902221088111
       
  • Numerical simulation of vortex-induced vibration of a smooth circular
           cylinder at the subcritical regime

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      Authors: Madjid Abbaspour, Navid Nemati Kourabbasloo, Pouya Mohtat, Araz Tanha
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The present paper focuses on the simulation of vortex-induced vibration (VIV) of a rigid, smooth circular cylinder with elastic supports subject to a cross-flow at the subcritical regime of Reynolds number, 30,000
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-04-03T07:10:31Z
      DOI: 10.1177/14750902221088429
       
  • Ship emissions reduction using weather ship routing optimisation

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      Authors: Clara Borén, Marcella Castells-Sanabra, Manel Grifoll
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      A significant proportion of global carbon dioxide emissions are attributed to ocean-sailing ships and shipping emissions are predicted to double in less than 30 years. This paper investigates the benefit of using weather ship routing optimisation, assessing the ship emissions for minimum distance routes and optimised routes. The present contribution merges the estimation of shipping pollutants and their mitigation through weather routing optimisation; two lines of research widely analysed separately but seldom discussed together. A previously developed open software of weather ship routing is used to obtain the minimum cost (i.e. optimised route) in terms of sailing time, using high-resolution wave forecasting. The assessment of fuel consumption and ship emissions calculations were inspired by the STEAM2 bottom-up approach, in conjunction with the estimation of the power increase needed to overcome speed decrement due to waves. Several scenarios covering the Western Mediterranean Short Sea Shipping routes (from 24 to 600 nautical miles and using a real Ro-Pax vessel) are compared in terms of emissions between the minimum distance route and the optimum. The ship routing optimisation reveals a reduction up to 30% of ship emissions during severe storms on longer routes. Nevertheless, all the cases studied show emissions mitigation when ship routing optimisation is used. The expected increase of extreme weather events, in terms of frequency, intensity and duration due to climate change, suggests a gradual gain of implementing weather ship routing optimisation in all types of routes, regardless of the distance.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-03-17T12:05:08Z
      DOI: 10.1177/14750902221082901
       
  • Study on vibration energy harvesting of offshore platform by energy
           harvester based on nonlinear energy sink

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      Authors: Zongyu Chang, Maokun Ge, Zhipeng Yao, Zhongqiang Zheng
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Under the impacts of waves and other marine environment, the jacket offshore platform has an obvious vibration and generates lots of energy. Meanwhile, the platform may suffer fatigue damage. The vibration energy harvesting of a jacket offshore platform under random waves with a nonlinear energy sink (NES) was investigated, and a NES-Energy harvester (NES-EH) was then designed by combining an electromagnetic linear generator with the NES. Moreover, the dynamic model of the NES-EH-offshore platform was built, and the electromagnetic damping and stiffness of the energy harvester were optimized by analyzing the energy capture efficiency and root mean square reduction of the platform displacement. The effects of NES nonlinear stiffness and damping, peak period and effective wave height of irregular waves on the capture power and width of the NES-EH were also analyzed. The results show that nonlinear stiffness and damping of the NES impact the energy capturing efficiency of the NES-EH; the smaller the damping and nonlinear stiffness, the higher the power captured by electromagnetic damping in the NES-EH. Compared with NES, the NES-EH system has a better effect on the vibration control of the platform and can better capture considerable vibration energy.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-03-10T01:22:25Z
      DOI: 10.1177/14750902221084836
       
  • Determining the optimal method to upgrade shipyard infrastructures for
           overhaul of offshore drilling rigs using genetic algorithm: A case study
           for ISOICO

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      Authors: Pantea Motamed, Javad Majrouhi Sardroud
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The purpose of this research is to select the optimal combination of infrastructure and equipment to upgrade a shipbuilding yard to repair offshore drilling rigs considering installation time and cost of the equipment needed and the overhaul cost and time of a rig. These four components constitute a four-objective problem. To solve this problem, a list of main equipment with various capacities and installation costs was developed. Then the cost and time of overhaul of drilling rigs, as well as the installation time of equipment were extracted using the Delphi method. Finally, the SPEA2 algorithm was employed to analyze the data. An optimal Pareto combination of equipment was obtained at a cost of $242.6 million, which can be provided in a maximum period of 200 months. The findings suggest the optimum way to equip shipyards for the overhaul of drilling rigs based on time and cost optimization for both rig and yard owners.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-02-24T10:49:34Z
      DOI: 10.1177/14750902221076937
       
  • An improved NMPC-NDOB scheme for trajectory tracking of unmanned surface
           vessel

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      Authors: Zhilin Liu, Shouzheng Yuan, Linhe Zheng, Yingkai Ma, Yuxin Sun
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This study investigates the trajectory-tracking problem of fully actuated unmanned surface vessels (USVs). A three-degree-of-freedom (3-DOF) dynamic model was used with three control variables: surge force, sway force, and yaw moment, where the model uncertainties, environmental disturbances, and actuator saturation were also considered. An improved nonlinear model predictive control (NMPC) method was investigated to improve the control performance in the trajectory tracking of USVs, and a nonlinear optimization problem based on the finite horizon was developed to minimize the divergence between the actual and the reference states. Moreover, a nonlinear disturbance observer (NDOB) was employed to estimate the environmental disturbance, which could enhance the robustness of the controller. Furthermore, an event-triggered mechanism was also employed to reduce the computational frequency of NMPC. Simulations of slide mode control, NMPC, and improved NMPC were performed in the trajectory-tracking control. Besides, the simulation results verified the effectiveness and robustness of the proposed improved NMPC-NDOB scheme.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-02-15T12:10:37Z
      DOI: 10.1177/14750902221079111
       
  • Safety analysis of a high-pressure fuel gas supply system for LNG fuelled
           vessels

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      Authors: Konstantinos Milioulis, Victor Bolbot, Gerasimos Theotokatos, Evangelos Boulougouris, Paul Sayan, Kelvin Wen Yong Chio, Wei Siang Lim
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The liquified natural gas (LNG) is currently considered an attractive marine fuel in the short- to medium-terms that can lead to the reduction of the shipping industry carbon emissions. LNG fuelled ocean-going ships have been designed by employing either low-pressure or high-pressure fuel systems. This study aims at enhancing the safety of a high-pressure fuel gas supply system (FGSS) designed for ocean-going LNG fuelled vessels. A model-based safety analysis is performed by employing the MADe™ software. The functional model of the baseline design of the investigated system is developed and subsequently employed to carry out the Failure Modes, Effects and Criticality Analysis (FMECA), as well as the quantitative Fault Tree Analysis (FTA). FMECA provided the risk priority number (RPN) for the identified system failure scenarios, the analysis of which leads to the identification of the FGSS critical components. The FTA results, which include the probabilities of the selected top events and appropriate importance metrics, are used for the FMECA results verification. This study results demonstrate that the FGSS critical components include the process valves responsible for supplying either LNG or natural gas to the gas treatment system and consumers respectively, as well as the pressure feedback controllers. Recommendations for design alterations pertain to the addition of pressure sensors and redundancy of the identified critical system components. The derived results demonstrate that impact of these design alterations on the calculated safety metrics are quite considerable, thus enhancing the safety of the baseline design. This study contributes to the safety analysis of FGGS and supports decisions for the designer and operator of LNG fuelled ships.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-02-15T12:08:37Z
      DOI: 10.1177/14750902221078426
       
  • Floating offshore wind turbines port requirements for construction

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      Authors: AP Crowle, PR Thies
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Floating offshore wind is an emerging technology that holds considerable potential to utilise areas deeper than 60 m for sustainable energy generation. As the floating offshore wind turbine industry continues to develop and grow, the capabilities of established port facilities need to be assessed as to their ability to support the expanding construction and installation requirements. This article assesses current infrastructure requirements and projected changes to port facilities that may be required to support the floating offshore wind industry. Understanding the infrastructure needs will help to identify the port-related requirements. Floating offshore wind turbines can be installed further out to sea and in deeper waters than traditional fixed offshore wind arrays, meaning they can take advantage of stronger winds and additional sea locations. Separate ports are required for substructure construction and fit-out of the turbines and maintenance. Large areas are required, about twice the plan area of the structure, for the laydown of mooring equipment, inter array cables, turbine blades and nacelles. The capabilities of established port facilities to support floating wind farms can be assessed by evaluation of size of substructures, height of wind turbine with regards to the cranes for fitting of blades, distance to offshore site and offshore installation vessel characteristics. Spar, barge, TLP and semisubmersible types have been deployed as demonstration units. Pre commercial units have been installed off the coasts of Portugal and the east coast of Scotland. This article reviews and defines the port and shipyard requirements for floating offshore wind turbines. It will support decision-makers to guide port infrastructure investments and project developers in their site selections. There up to 15 port functions that need to be considered, for construction, assembly and support of offshore activities. These could be fulfilled by one or a combination of different ports.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-02-15T10:20:23Z
      DOI: 10.1177/14750902221078425
       
  • Stability and drag reduction in turbulent flow of skin with quasi-periodic
           elastic supports

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      Authors: Lu Chen, Shaogang Liu, Dan Zhao, Hongtao Guo, Jundong Wei, Yuxin Liu
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      In order to reduce the flow resistance on the surface of ships, the skin with quasi-periodic elastic supports is designed based on the flexible skin drag reduction technology inspired by dolphin skin. In this paper, the stability characteristic equation of fluid-structure coupling system is established based on small perturbation theory and solved by MATLAB. The results indicate that the skin with quasi-periodic elastic supports has the ability of maintaining stability of turbulent boundary layer when the structural parameters are reasonable. In addition, the drag reduction performance of the skin with quasi-periodic elastic supports is studied by immersion boundary method. The analysis results demonstrate that the skin with quasi-periodic elastic supports can show better drag reduction performance than the skin with periodic elastic supports when the structural parameters q and the support spacing L are rationally set. In a certain speed range, the relative drag reduction rate is up to 72.16%. These optimal distribution parameter data of the skin under certain speed conditions obtained in this paper provide a reference for the practical application and intelligent optimization design of the skin with quasi-periodic elastic supports.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-31T08:39:07Z
      DOI: 10.1177/14750902221076239
       
  • Investigation of the adverse effects of slow steaming operations for ships

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      Authors: Caglar Dere, Burak Zincir, Omer Berkehan Inal, Cengiz Deniz
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The typical negative effects of prolonged slow steaming operations are investigated in this study. The scope of the research is to examine the effects of the carbon deposit formation on piston rings (lack of sealing function), exhaust boiler (reduction in the heat recovery capacity), turbocharger (lack of scavenging capacity), and injector, due to the prolonged slow steaming operation. It is necessary to identify the holistic adverse effects of the low-load operation on the main engine performance and subsequent components. The study shows that the negative consequences of a long-term slow steaming operation cause noteworthy efficiency degradation in marine diesel engines. The paper aims to clarify the barriers to the efficient operation of marine diesel engines via raising awareness of proper and planned maintenance for sustainable slow steaming. The degradation rates affect the total operational efficiency, CO2 emissions, and fuel consumption. The study results show that the fuel consumption increases by 1.9%, 2.1%, and 1.9% of daily consumption and the corresponding CO2 emission increments are 4.36, 4.29, and 3.48 kg CO2 per nautical mile sailing of the container ship at specified speeds at 65%, 55%, and 45% engine loads, respectively. The efficiency variation leads significant amount of emission increment, while up to 50% decrement will enter into force by April 2022 for container ships. The study gives valuable insight into the increase in CO2 emissions and fuel after long-term slow steaming for the near future with the stricter emission limits. The results provide considerable information about the deterioration effect on the whole energy system and help to estimate potential efficiency levels for marine diesel engines.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-21T08:55:02Z
      DOI: 10.1177/14750902221074191
       
  • Experiments on vibration transmission control in a shaft-hull system
           excited by propeller forces via an activemulti-strut assembly

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      Authors: Xiling Xie, Mingke Ren, Yueyue Zhu, Zhiyi Zhang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The active control of lateral vibration transmission in a shaft-hull system with an active multi-strut assembly was investigated experimentally. The lateral vibration of the shafting system excited by the propeller forces transmits to the hull structure through the active multi-strut assembly, and the embedded actuator in each strut generates control forces to suppress vibration transmission. Modal testing was conducted and the characteristics of the hull structure were obtained. The excitation was exerted by two shakers mounted on the stern bearing housing. The performance of vibration suppression was verified for two control strategies that use three and six error transducers, respectively. Experimental results have demonstrated that the active multi-strut assembly in combination with the adaptive control method is able to suppress the vibration transmission from the shaft to the hull, and accordingly reduces the vibration of the hull surface. Moreover, the control strategy using six error transducers is of stronger cross coupling in the control channels as compared to that using three error transducers, which consequently makes it harder to implement active control.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-19T05:23:59Z
      DOI: 10.1177/14750902211065850
       
  • Bow shape modification through multi-objective hydrodynamic optimization:
           Methodology comparison between CAD-based FreeForm Deformation and
           Mesh-based Radial Basis Function approach

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      Authors: Parviz Ghadimi, Amin Nazemian
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Marine industrial engineering face crucial challenges because of environmental footprint of vehicles, global recession, construction, and operation cost. Meanwhile, Shape optimization is the key feature to improve ship efficiency and ascertain better design. Accordingly, the present paper proposes an automated optimization framework for ship hullform modification to reduce total resistance at two cruise and sprint speeds. The case study is a bow shape of a wave-piercing bow trimaran hull. To this end, a multi-objective hydrodynamic problem needs to be solved. A combined optimization strategy using CFD hullform optimization is presented using the software tools STAR-CCM+ and SHERPA algorithm as optimizer. Furthermore, a comparison is made between CAD-based and Mesh-based parametrization techniques. Comparison between geometry regeneration methods is performed to present a practical and efficient parametrization tool. Design variables are control points of FreeForm Deformation (FFD) for CAD-based method and Radial Basis Function (RBF) for Mesh-based method. The optimization results show a 4.77% and 2.47% reduction in the total resistance at cruise and sprint speed, respectively.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-12T12:52:07Z
      DOI: 10.1177/14750902211068929
       
  • Study on the application of BP neural network optimized based on various
           optimization algorithms in storm surge prediction

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      Authors: Xiao-qi Zhang, Si-qi Jiang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      Storm surge prediction is of great importance to disaster prevention and mitigation. In this study, four optimization algorithms including genetic algorithm (GA), particle swarm optimization (PSO), beetle antenna search (BAS), and beetle swarm optimization (BSO) are used to optimize the back propagation neural network (BPNN), and four optimized BPNNs for storm surge prediction are proposed and applied to Yulin station and Xiuying station at Hainan, China. The optimal model parameter combination is determined by trail-and-error method for the best prediction performance. Comparisons with the single BPNN indicate that storm surge can be efficiently predicted using the optimized BPNNs. BPNN optimized by BSO has the minimum prediction error, and BPNN optimized by BAS has the minimum time cost to reduce unit prediction error.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-10T05:43:08Z
      DOI: 10.1177/14750902211069551
       
  • Outlier analysis of sloshing impact loads on liquid ship cargo

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      Authors: Sang-Yeob Kim, Yonghwan Kim, Yang-Jun Ahn
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This paper introduces an outlier analysis which can improve the convergence of the statistical analysis results of sloshing model test data. The paper classify possible outliers in the sloshing model test into three categories and present a treatment method for each outlier. The developed outlier analysis is adapted to the model test results for the cargo of the liquefied-natural-gas (LNG) carrier in operation. The results of the present new method are compared with those of the conventional procedure, particularly focusing on long-term sloshing prediction. Through this study, the effectiveness of the present method is observed, and it is found that the present method provides is robust and reliable results in the application of experimental data for load prediction.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-10T05:37:50Z
      DOI: 10.1177/14750902211069548
       
  • Prediction of drag and lift forces of a high-speed vessel at full scale by
           CFD-based GEOSIM method

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      Authors: Ugur Can, Sakir Bal
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      In this study, it was aimed to obtain an accurate extrapolation method to compute lift and drag forces of high-speed vessels at full-scale by using CFD (Computational Fluid Dynamics) based GEOSIM (GEOmetrically SIMilar) method which is valid for both fully planing and semi-planing regimes. Athena R/V 5365 bare hull form with a skeg which is a semi-displacement type of high-speed vessel was selected with a model family for hydrodynamic analyses under captive and free to sinkage/trim conditions. Total drag and lift forces have been computed for a generated GEOSIM family of this form at three different model scales and full-scale for Fr = 0.8 by an unsteady RANS (Reynolds Averaged Navier–Stokes) solver. k–ε turbulence model was used to simulate the turbulent flow around the hulls, and both DFBI (Dynamic Fluid Body Interaction) and overset mesh technique were carried out to model the heave and pitch motions under free to sinkage/trim condition. The computational results of the model family were used to get “drag-lift ratio curve” for Athena hull at a fixed Fr number and so the corresponding results at full scale were predicted by extrapolating those of model scales in the form of a non-dimensional ratios of drag-lift forces. Then the extrapolated full-scale results calculated by modified GEOSIM method were compared with those of full-scale CFD and obtained by Froude extrapolation technique. The modified GEOSIM method has been found to be successful to compute the main forces (lift and drag) acting on high-speed vessels as a single coefficient at full scale. The method also works accurately both under fully and semi-planing conditions.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:32:34Z
      DOI: 10.1177/14750902211070743
       
  • Assessing the investment environment in container terminals: A knowledge
           gap model

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      Authors: Wen-Kai K Hsu, Hui-Huang Tai, Nguyen Tan Huynh, Jun-Wei C Chen
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      This paper aims to evaluate the investment environment in container terminals (CTs) in one seaport from the attitudes of both terminal operators (TOs) and port companies (PCs). Evaluation criteria (ECs) regarding the investment environment in CTs are first created based on the prior literature and the CTs’ operational characteristics. A knowledge gap model based on an improved fuzzy AHP approach is then developed to assess the perceived differences on the ECs between TOs and PCs, by which the PCs managers could formulate practical policies to improve their investment environment in CTs. As an empirical study, the Taiwan International Port Corporation (TIPC) and its terminal operators in Kaohsiung port are examined to verify the research model. Results indicate that ECs with higher knowledge gap for TIPC include: Intra-port coopetition, Number of shipping carriers, and Business tax. Based on the result, theoretical and managerial implications are discussed.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:30:42Z
      DOI: 10.1177/14750902211070739
       
  • Active axial vibration control of a shaft-bearing system excited by the
           dynamic thrust force

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      Authors: Mingke Ren, Xiling Xie, Dequan Yang, Zhiyi Zhang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The axial vibration of a shaft-bearing system induced by the thrust excitation is usually composed of multiple tones. To suppress the axial vibration of the shaft-bearing system, two inertial electro-magnetic actuators are mounted symmetrically at the thrust bearing and work in parallel to exert control forces. The control signal is generated by an adaptive algorithm with subband filtering, which aims to attenuate over a broadband the vibration of the thrust bearing and its foundation induced by the dynamic thrust force. To reduce computational complexity, the recursive computation is partly realized with the auto-regressive moving average (ARMA) model. The proposed active control approach is evaluated numerically at first with the dynamic model of the shaft-bearing system and then verified with an experimental system. It is demonstrated by the numerical and experimental results that the active control approach is able to suppress the multi-tone vibration of the thrust bearing and the foundation. Moreover, in comparison to the single-band adaptive feedback algorithm, the adaptive algorithm with subband filtering is more effective when the disturbance contains multiple tones.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:28:34Z
      DOI: 10.1177/14750902211070226
       
  • Seasonality of cruise ship activityin neighboring regions

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      Authors: Jeronimo Esteve-Perez, Antonio Garcia-Sanchez
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The continuous growth of the cruise industry has brought with it a series of threats. Among them is the management of the seasonality of cruise activity in order to address its negative effects. This study examines the monthly cruise passenger movement distribution among a group of harbors located in the northeast sector of the Atlantic Ocean and the Baltic Sea with the aim of determining the existence of seasonality patterns in cruise traffic and their relationship between different regions. A database of cruise passenger movements during the period from 2007 to 2019 among 24 harbors forms the backbone of the empirical analysis. First, the seasonal variation index of each harbor was calculated to determine the seasonality pattern. Second, a cluster analysis was performed to classify harbors into clusters with analogous seasonality patterns. The results reveal that seasonality of cruise activity in a consolidated region is explained by own factors of the region, but also by an induced seasonality imported from neighboring cruise regions.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:25:55Z
      DOI: 10.1177/14750902211070224
       
  • Numerical simulation of the mooring capacity comparison of the subsea
           suspended manifold with two mooring schemes

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      Authors: Ning Xu, Honglin Zhao, Yufang Li, Yingying Wang, Shimin Zhang
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The next-generation underwater production system (NUPS) is based on the suspension cluster manifold (SCM) as a new conceptual scheme. SCM mooring stability is essential for establishing NUPS. Therefore, comparing the SCM mooring stability in different mooring systems is vital for evaluating system adaptability. This paper detailed two mooring schemes designed for the SCM, including the steel catenary riser (SCR) mooring system and the new steep wave (NSWR) mooring system. OrcaFlex software was used to establish the mooring system model, analyzing the static motion response of the SCM under the current and fluid density. Furthermore, the mooring system adaptability in the cluster wellhead layout was also evaluated and compared. The results showed that the maximum offset of the SCM with the SCR mooring system was within 2 m under the current, while the deflection of the SCM with the NSWR mooring system was within 1.5° in extreme fluid densities. Furthermore, the SCM with the SCR mooring system displayed superior station-keeping capability in the current, while the NSWR mooring system exhibited better stability when transporting extreme fluid densities and was more adaptable in cluster wellhead layouts.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:24:29Z
      DOI: 10.1177/14750902211070105
       
  • A novel hybrid energy management strategy of a diesel-electric hybrid ship
           based on dynamic programing and model predictive control

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      Authors: Yupeng Yuan, Mingshuang Chen, Jixiang Wang, Wanneng Yu, Boyang Shen
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The energy-saving characteristics of diesel-electric series hybrid ships largely depend on their energy management strategy. In this paper, a strategy that combines dynamic programing and model predictive control (DP-MPC) is proposed to solve the energy management problems of diesel-electric hybrid ships. The DP-MPC strategy has considered some typical working conditions of a ship, and the corresponding influence of white noise disturbance on the control strategy was studied. The simulation results show that the DP-MPC strategy has an excellent anti-interference capability. The control performance of the DP-MPC strategy is then further analyzed and compared with the rule-based logic threshold control strategy. The simulation results show that the proposed DP-MPC strategy can save 2.5% of the fuel consumption and has a better anti-interference capability than the rule-based control strategy.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:20:35Z
      DOI: 10.1177/14750902211068931
       
  • Comparative study of offshore spar-buoy oscillating water column dynamic
           models for captured power estimation

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      Authors: Seif Bayoumi, Erkan Oterkus, Hassan El-Gamal, Atilla Incecik
      Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
      The prompt estimation of power and geometrical aspects enables faster and more accurate financial assessment of wave energy converters to be deployed. This may lead to better commercialisation of wave energy technologies, as they require location-based customisation, unlike the mature wind energy technologies with developed benchmark. The adopted approach provides simple and efficient modelling tool allowing the study of the system from different perspective. The aim of this study is to select the optimum dynamic model to predict the captured power of a spar-buoy Oscillating Water Column (OWC) wave energy converter. Four dynamic models were developed to predict the system dynamics and results were validated experimentally. In-depth investigations on the effect of the mass and damping ratios of the oscillating bodies on the accuracy of the adopted models were performed. Such investigations included the proposed one-way coupling model and three two-degree of freedom models and three reduced-scale models, in addition to analytical and numerical solutions. Pneumatic power was calculated for the reduced-scale model where orifices’ covers simulated the power take-off mechanism damping experimentally. Analysis and comparisons between the adopted models are finally provided.
      Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
      PubDate: 2022-01-08T10:19:18Z
      DOI: 10.1177/14750902211067757
       
 
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