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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 (It can contain Open Access articles)
ISSN (Print) 1475-0902 - ISSN (Online) 2041-3084
Published by Sage Publications

[1176 journals]

Numerical investigation of interference effects for the Delft 372
catamaran
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  Authors: Andrea Farkas, Nastia Degiuli, Ivan Tomljenović, Ivana Martić
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Due to interference effects, the resistance of a catamaran is not the same as the double resistance of the monohull. If demihulls are close enough to each other, the wave fields generated by each demihull usually significantly interfere causing either advantageous or disadvantageous effects. In this paper, the numerical investigation of interference effects for the Delft 372 catamaran is performed. The verification and validation studies are performed demonstrating the potential of the proposed numerical model for the analysis of interference effects. The investigation of the effect of Froude number and demihull separation on the total resistance of a catamaran, trim angle, and sinkage is conducted. The interference effects are quantified through the interference factor, which is defined based on the total resistance of a catamaran and double the total resistance of the monohull. Finally, the flow field characteristics, wave patterns, and pressure distributions are analysed using Computational Fluid Dynamics.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-09-11T08:12:27Z
  DOI: 10.1177/14750902231197886
Determination of particle paths and hydrodynamic forces of random wind
forced nonlinear ocean waves
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  Authors: Marten Hollm, Leo Dostal, John D Carter, Robert Seifried
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  The hydrodynamic forces of nonlinear deep water gravity waves acting on cylindrical offshore structures are studied. Thereby, the waves are excited by random wind and the corresponding effect on the particle paths and hydrodynamic forces is investigated. This is done for the Peregrine breather solution of the nonlinear Schrödinger equation, which is nowadays considered as a prototype of extreme waves in open seas. Using this theory, the loads on mechanical structures can be calculated efficiently. It is shown that the Peregrine breather can exist under strong and gusty wind conditions and the water particles experience a horizontal drift. This leads to a force with randomly increasing amplitude in time, whereby a mean wind velocity of 50 km/h results in an increase of about 3%. The increase of hydrodynamic forces caused by the wind should therefore be considered for the construction of mechanical structures operating in the ocean.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-09-08T11:35:07Z
  DOI: 10.1177/14750902231196812
LAW-IFF Net: A semantic segmentation method for recognition of marine
current turbine blade attachments under blurry edges
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  Authors: Fei Qi, Tianzhen Wang, Xiaohang Wang, Lisu Chen
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Challenges exist in the power generation efficiency and safety of marine current turbines (MCTs), as the MCT blades are often attached by foreign objects when operating underwater. It is essential for the stable operation of an MCT to recognize attachments timely and accurately. However, underwater imaging suffers from blurry edges due to light attenuation and scattering. It is challenging for accurate recognition through underwater images since blurry edges result in unclear edge features. To alleviate this problem, LAW-IFF Net is proposed in this paper, which mainly contains two parts. Firstly, this paper proposes to transform the local averages of feature maps into weight matrices, namely the locally average weighting (LAW) mechanism. It is intended to alleviate the edge gradient reduction caused by blurry edges. Secondly, the proposed improved feature fusion (IFF) mechanism aims to overcome the deviation caused by the feature fusion of different attention branches based on spatial attention. At the same time, the lightweight networks are combined with the proposed method to improve the computation speed and ensure the timeliness of recognition. Experimental results on the MCT dataset show the superiority of the proposed method in terms of accuracy and speed of attachment recognition in images with blurry edges. The experimental results on publicly available datasets show the applicability of the proposed method to other underwater images.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-09-05T10:15:26Z
  DOI: 10.1177/14750902231192145
Waste heat recovery assessment of triple heat-exchanger usage for ship
main engine pre-heating and fresh water generation systems
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  Authors: Köksal Çolak, Hasan Ölmez, Betül Saraç
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  In this study, the applicability, fuel saving and CO2 emission reducing potential of the triple heat-exchanger fed by the diesel generator exhaust gas with and without water steam have been studied for ship’s one and two main engines pre-heating and freshwater generation (FWG) cycles under port conditions with conducting energy and exergy analysis. The performance criteria (PC) and exergy efficiency (ε) values of the main engine pre-heating and freshwater generator systems of the Ro-Ro ship selected for the case study were determined by written Matlab 2021a codes merging CoolProp 6.4.2 database with Python. It was determined that even at the lowest operating load of the diesel generator (25%), the exhaust heat energy would be sufficient to preheat the main engine and generating fresh water with also saving fuel consumption. As a result, during the 12-h port period, each 1 kW heat energy reduction on steam will provide 0.0853 kg/h fuel saving in the boiler. Thus, 273 kg CO2 emission will be reduced for each kW of heat energy to be obtained. Considering the comparatively increased PC and ε values of whole system cycle containing common triple heat-exchanger for two main engines, it can be used conveniently and reliably on ships.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-08-30T08:13:43Z
  DOI: 10.1177/14750902231194794
Application of IT2Fs-AHP and TOPSIS modeling for performance analysis of
tank coatings in chemical tankers
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  Authors: Murat Mert Tekeli, Elif Bal Besikci, Muhammet Gul, Emre Akyuz, Ozcan Arslan
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  There are a wide range of chemical cargoes carried in chemical tankers. The chemical tankers are carrying hazardous chemical cargoes in their cargo tanks. When carrying hazardous chemicals in cargo tanks, the coating is required which is to provide safety barrier between the hull plate and the cargo. Therefore, capabilities of cargo tanks are of paramount importance for safe and efficient transport. Tank coatings to be applied to chemical tankers are epoxy coatings, zinc silicate coating, stainless steel coating, and marine line coating. This paper aims at conducting a numerical performance analysis of tank coatings in chemical tankers to contribute decision-making process of shipowner and safety professionals. To achieve this purpose, a multi-criterion decision-making (MCDM) tool is adopted: An Analytical Hierarchy Process (AHP) and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) under interval type-2 fuzzy set (IT2Fs) environment. The outcomes of the numerical performance analysis showed that stainless steel type tank coating has the best performance since result of closeness coefficient value c(xj) is found 0.55. The findings of the research will contribute chemical tanker ship owners, safety inspectors, naval architects, and safety professionals during decision-making process of ideal cargo tank coating.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-08-30T05:34:43Z
  DOI: 10.1177/14750902231194703
Direct strength calculation of an aged single-bottom tanker during its
towing in waves
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  Authors: Nikola Vladimir, Ivo Senjanović, Ivana Jovanović, Stipe Tomašević, Paul Jurišić
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Large engineering structures like ships and other floating structures require reliable and complex computations to ensure their structural integrity over their lifetime. This work presents an analysis of the structural integrity of an aged single-bottom tanker during its towing from Croatia to a scrapheap in Turkey. The ship is subjected to wave loading (corresponding to the global response) and towing force (corresponding to the local response). Computations were performed by a general hydro-structure tool that combines a 3D finite element (FE) structural model and a 3D boundary element (BE) model based on the Rankine panel theory, according to the guidelines of the relevant classification society. Time domain simulations were performed to take account of Froude-Krylov nonlinearities for a wave determined within the Equivalent Design Wave (EDW) approach. After the calculation of wave loading and its transfer to the FE model of a ship structure, the stresses were calculated and compared with the allowable values. The local strength assessment of the ship forecastle deck structure was also performed, considering the prescribed towing force as an imposed load. Both the procedure and the used computational tools are general and can be applied to any kind of ship or other floating structure.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-08-01T06:04:14Z
  DOI: 10.1177/14750902231189917
Multi-objective optimization design of shaftless rim-driven thruster
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  Authors: Bian Tao, Liu Liangliang, Cai Wenhao, Jiang Wen, Liu Zhiwen
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This paper proposes a multi-objective optimization design method for shaftless rim-driven thruster (RDT) based on the ISIGHT platform. The pitch ratio, the blade area ratio and the advance coefficient of RDT were considered as the design optimization variables, the thrust and efficiency of the RDT were the optimization objectives. The multi-objective optimization design method was based on the surrogate module and the optimization module in the ISIGHT platform. Two analytical methods (response surface methodology (RSM) and radial basis function Model (RBF)) were used to build the surrogate model. The Muti-Island GA optimization algorithm was adopted in the optimization module. The paper indicates that both RSM model and RBF model are feasible to build the surrogate model, the RBF model has better accuracy and reliability than RSM model. The blade obtained by RBF method has larger thrust and smaller torque than that of the blade obtained by RSM method. For the large advance coefficient (J > 0.6), the efficiency of the blade obtained by RBF method is slightly higher than that of the blade obtained by RSM method.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-07-24T06:22:00Z
  DOI: 10.1177/14750902231188393
Performance analysis of a horizontal axis current turbine blade section
with inserted tube
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  Authors: Parikshit Kundu, Ashoke De
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Generating more usable power annually from the river and tidal currents is essential to improving cost-effectiveness. Among various alternative options, the performance improvement of the blade foil has been considered in this work. When the fluid over the blade surface loses kinetic energy, flow separation occurs. The lift forces are reduced by flow separation, which finally results in less power production by the horizontal axis current turbine. To extract more power, it is necessary to overcome this flow separation. This paper presents a passive flow control method using tubes at regular intervals on the blade section to improve its performance considering its application on a horizontal axis current turbine. The tube inlet and outlet positions are determined by analyzing the force coefficients, glide ratio, and stall angle for a specific angle of attack. Finally, the performance characteristics are compared between the baseline and the modified hydrofoil. The maximum lift coefficient of the hydrofoil is increased by 15.7%. Also, the maximum glide ratios are considerably increased beyond the stall of the baseline profile. From the numerical results, it can be concluded that tubes inserted at regular intervals on the hydrofoil significantly increase its performance at a higher angle of attack.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-07-21T12:13:09Z
  DOI: 10.1177/14750902231185807
Study on predictability of ocean wave fields based on marine radar
measurement data
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  Authors: Jae-Hoon Lee, Yoon-Seo Nam, Yuming Liu, Heesuk Yang
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  In this study, the predictability of ocean wave fields is considered based on marine radar measurement data. Phase-resolved components obtained by applying 3D FFT-based reconstruction to a sequence of radar images are utilized for wave field prediction, and two different prediction approaches are introduced: (i) snapshot data-based prediction through the adjustment of the frequency and phase of each component, and (ii) spatiotemporal data-based prediction through the data assimilation for reconstructed wave fields. Furthermore, the time evolution of a predictable zone is derived for different shapes of measurement domains including rectangular and ring-shaped domains. To validate the proposed wave propagation modeling method, numerical simulations are conducted on synthetic radar images created by reflecting geometrical shadowing effects, and the prediction accuracy is examined in relation to the derived predictable zone. Lastly, the forecasting performance, which is represented by the predictable time range at a radar location, is discussed with respect to the prediction techniques, specifications of the reconstruction domain, and moving measurements.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-07-10T10:28:28Z
  DOI: 10.1177/14750902231184096
Numeric assessment of the effect of the twin island design on the airflow
dynamics around a generic aircraft carrier
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  Authors: Ankit Nehra, Vijayakumar Rajagopalan
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  The twin island concept is the most recent innovation in the top-deck architecture of an aircraft carrier. The carrier’s bluff body design presents the pilot with a number of difficulties, with landing on deck posing the biggest problem. The goal of the current study is to carry out the numerical analysis of the aerodynamic behaviour of twin island structure on Generic Aircraft Carrier. The flow characterization has been performed utilizing the normalized axial velocity and turbulent kinetic energy as aids for establishing pilot workload along the glideslope line. In this paper, multiple transverse planes cut across perpendicular to the flow direction are used to analyse the flow across the flight deck of twin island GAC and its downstream. The impacts of the two islands’ longitudinal translations with regard to the initial GAC position were then investigated and the results were analysed and compiled with reference to the landing approach path of the aircraft. The results show that the twin island designs are preferable to a single island. The maximum advantage in terms of turbulence reduction is achieved when the bifurcated islands are longitudinally repositioned forward of the original single island design position. The modified design not only achieves a 72% reduction in peak turbulence but also provides an additional time advantage to the pilot for assessing the environmental conditions while he is approaching the carrier flight deck for landing thus aiding to efficiently and effectively manage the workload. The findings of this study can act as a driving force for the integration and application of twin island concept in future design plans for floating structures and further studies in the field.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-06-24T08:12:09Z
  DOI: 10.1177/14750902231183198
The hydrodynamic characteristics of autonomous underwater vehicles in
rotating flow fields
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  Authors: A Mitra, JP Panda, HV 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 hydrodynamic characteristics of Autonomous Underwater Vehicles (AUVs) are investigated and analyzed under the influence of rotating flow fields, which were generated in a recirculating water tank via a rotating propeller. Initially, experiments were carried out to measure flow field variables and quantities of Interest across the AUV in the presence of the rotating propeller while varying the rotational speed and the extent of rotational flow strength. The flow field across the AUV was measured using an Acoustic Doppler Velocimeter (ADV). These measured turbulent flow statistics were used to validate the Reynolds Stress Model (RSM) based numerical predictions in a commercial CFD solver. After preliminary validation of the turbulent flow statistics with the numerical predictions, a series of numerical simulations were performed to investigate the effect of the rotational flow field of the propeller on the drag, skin friction, and pressure coefficients of the AUV. The operating speed and location of the propeller were also varied to check their effects on the hydrodynamic performance of the AUV. The results provided in this article will be useful for the design optimization of AUVs cruising in shallow water where the flow is highly rotational because of wave-current interactions. Additionally, the results and analysis are relevant to study the design and operation of AUVs that have to operate in a group of unmanned underwater vehicles or near submarines and ships where the flow field is highly complex and such rotational effects are present.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-06-22T09:34:31Z
  DOI: 10.1177/14750902231181843
Effect of d-type rib roughness on the turbulent structure of side wall
boundary layer for wave-current combined flow
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  Authors: Sunil Hansda, Koustuv Debnath, Debashis Pal
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  An experimental study has been carried out in a laboratory flume to characterize the turbulence structure and turbulence anisotropy in the boundary layer over smooth and rough side walls for both current alone and wave-current combined flow situations. The rough side wall of the flume comprises a train of circular ribs (diameter, k) attached vertically maintaining uniform spacing p along the streamwise direction. The experiments are performed for smooth surface and rough (ribbed) surfaces with p/k = 2, 3, and 4 to reproduce different cases of d-type rib roughness. The effect of wave-current interaction has been investigated by superposing waves of two different frequencies. Time series data of three velocity components are obtained using Acoustic Doppler Velocimeter. At the near wall region, roughness with higher p/k value enhances the level of turbulent intensity and Reynolds stress significantly. In a channel with smooth side wall, the wave-current combined flow produces lesser turbulence intensity than the current alone flow near the wall. However, for a ribbed wall case, the effect is completely opposite that is, wave-current interacting flow induces higher intensities compared to the reference current alone flow. Substantial decline in the turbulent length scales at the near wall region are observed for ribbed walls, which reveals the strong effect of roughness elements on the turbulent structure. Superposition of wave reduces the length scales even more for both smooth and rough wall cases. As the spacing between two ribs (p/k ratio) increases, the energy dissipation rate increases. The analysis of anisotropy invariant map demonstrates a reduction of anisotropy in the vicinity of ribbed wall compared to that for a smooth wall. For wave-current combined flow, the anisotropy invariant data of Reynolds stress tensor varies dramatically within the boundary of map, reflecting significant changes in the state of turbulence.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-06-22T09:28:14Z
  DOI: 10.1177/14750902231181505
Dynamic analysis of a porous wall fencing offshore fish cage subjected to
regular waves
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  Authors: Shaik Abdul Shareef, Nasar Thuvanismail, Sai Kiran Naik E, Manisha Vijaykumar
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Global aquaculture is in exponential trend to fulfil the demand for seafood due to the rise in world population. Most countries have implemented nearshore farming and reached their limits, which impacts water quality parameters. Offshore farming is the alternative option to counteract this nearshore farming issue and balance the aquaculture demand and supply. The present study construes on the numerical study of the porous wall fencing offshore fish cage subjected to regular waves. The numerical analysis is carried out for four cages by varying porous hole diameters from 0.5 to 0.7 m and without porosity. All the cages are placed at the same water depth of 200 m, interacting with a constant wave height of 6m with wave periods ranging from 6.92 to 19.05 s. Both frequency and time domain analysis are conducted to study the variation of hydrodynamic parameters, namely added mass, wave excitation forces, radiational potential damping, motion responses, and mooring line tension. Among all cage configurations, the cage with 0.5 m diameter porous hole fencing performs better for all wave conditions considered. Also, a scaled model of 1:75 was considered in both experimental and numerical studies for the purpose of validation. It is learnt that experimental parameters such as motion responses and mooring line tension are in good agreement.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-06-07T06:06:59Z
  DOI: 10.1177/14750902231177337
Development of a novel, robust, near-shore, wave energy converter for
energy security in remote communities
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  Authors: Rachel Nicholls-Lee
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This work aimed to test the feasibility, both experimentally and numerically, of a novel concept for a robust Wave Energy Converter (WEC) operating in the near-shore region. The converter uses a series of non-return valves, constrained by a tapered pipe, where the incoming wave builds up pressure in each compartment and finally drives a turbine onshore with the pressurised water. The device is aimed at remote communities, to gain energy security and reduce dependence on imports. The device facilitates local engagement, and it is intended that local people are trained to perform most maintenance tasks using low cost, readily available, parts. This work assessed the feasibility of the WEC through physical testing, the results of which were compared to initial numerical models. The device was shown to capture energy and, through a case study of Ushant Island off the coast of France, was shown to have the potential to become part of the future energy mix for remote communities.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-05-16T05:51:56Z
  DOI: 10.1177/14750902231172821
LCA approach for environmental impact assessment within the maritime
industry: Re-design case study of yacht’s superstructure
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  Authors: Francesco Del Pero, Caterina Antonia Dattilo, Alessandro Giraldi, Massimo Delogu
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Sustainable development, one of the main challenges of our time, is a policy focused on the perfect balance between three fundamental pillars: environmental, economic and social sustainability. As regards the environmental protection, the Life Cycle Assessment (LCA) methodology allows to evaluate the sustainability profile of the overall Life-Cycle (LC) of products, processes and services, based on an inventory (in terms of materials/energy consumption and emissions/waste production) referred to all LC stages. The paper describes an application of LCA in the maritime transportation field, after a careful analysis of the state of the art. In particular, the case study consists in the environmental comparison of two alternative design solutions for the superstructure of a Azimut-Benetti yacht, designed by Corporate R&D department and manufactured in one of Benetti botyards. The competing construction options are a Glass Fiber reinforced Vinylester-isophthalic Resin (GFVR) and a Carbon Fiber reinforced Epoxy Resin (CFER) component, and they are assessed in terms of Global Warming Potential through the CML2001 Life Cyle Impact Assessment (LCIA) method. The study takes into account the entire LC of the superstructure component, divided into production (including raw materials, manufacturing and transportations), use (including both fuel consumption and exhaust air emissions) and End-of-Life (EoL). The Life Cycle Inventory (LCI) is mainly based on primary data (materials and energy consumption for manufacturing) directly provided by the construction company; missing data are retrieved from secondary sources (literature and LCI database provided by the GaBi6 environmental software). Results show that, despite the higher impact in production stage, the innovative solution allows achieving a significant quota of GWP over the entire LC (more than 16%), which is mainly associated with decreased amount of fuel needed and lowered CO2 exhaust emissions during operation. The sensitivity analysis reveals that the environmental advantage provided by the CFER design becomes bigger as both component life-time and yacht consumption increase.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-05-10T05:10:51Z
  DOI: 10.1177/14750902231173470
Dynamic modeling and control of hydraulic driven payload anti-swing system
for shipborne cranes
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  Authors: Guoliang Jin, Yuqing Sun, Hongyu Cheng, Hailong Sun, Shenghai Wang, Haiquan Chen
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Shipborne cranes are widely used in marine engineering and are employed in more diversified working scenes. However, due to the extensive swing range of ships, it is impossible to locate the payload accurately. A constant tension control method of payload anti-swing is proposed based on the principle of linear velocity feedback. This paper establishes a dynamic model of the payload anti-swing system driven by hydraulic motors. The characteristics of the payload swing and the cable tension are obtained through the dynamic simulation. The simulation and experimental results show that the constant tension control method significantly suppresses the shipborne crane’s payload swing, and the payload anti-swing effect reaches 73% and 85.6%. It is also found that the payload swings asymmetrically under external excitation. In addition, the effects of payload asymmetric swing on cable tension, payload swing angle, and the hydraulic pump output oil pressure are studied by a payload asymmetric swing experiment, and the results show that the proposed method also has a good suppression effect on the asymmetric payload swing.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-28T07:19:19Z
  DOI: 10.1177/14750902231170914
The application of laminar numerical wave tank for a heaving buoy
hydrodynamics study in low-turbulence nonlinear waves
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  Authors: Yijun Sun, Ahmed A Hamada, Omar Sallam, Björn Windén, Mirjam Fürth
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Numerical Wave Tanks (NWTs) allow for in-depth investigations into the hydrodynamics and wave responses of floating objects. Thus, they are widely used during the design phase of many offshore platforms and devices. Such problems often feature low turbulence, with wave propagation and wave-object interaction being the key features. In this paper, the merits of using a laminar flow model for a NWT with a free-to-heave buoy, subject to second order Stokes waves in a low sea state is investigated. The simulations are implemented using the interFoam solver, which is embedded in OpenFOAM. The time series of waves measured upstream and downstream of the buoy, and the buoy hydrodynamics are compared to analytical and experimental results for accuracy evaluations. It is shown that, due to the low turbulence level of the problem, the laminar approach can deliver more accurate results than turbulent models, such as Reynolds-averaged Navier-Stokes Simulation (RANS) or partially-averaged Navier-Stokes Simulation (PANS). Moreover, the simulation time of the laminar simulations is significantly shorter than to those of RANS and PANS.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-20T06:37:33Z
  DOI: 10.1177/14750902231168674
A semi analytic method for the analysis of the symmetric hydroelastic
response of a container ship under slamming and green water loads
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  Authors: Debasmit Sengupta, Tushar Kanti Show, Spyros Hirdaris, Ranadev Datta
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This paper presents a semi analytic time domain method for the analysis of the symmetric hydroelastic response of a container ship subject to slamming and green water loads. An Impulse Response Function (IRF) is adopted for the calculation of radiation, diffraction and wave excitation forces. Local hydrodynamic forces associated with green water on decks and slamming loads are respectively modelled by the Buchner’s Dam Break Model and a Generalised Wagner Model. The structural responses are captured by Euler-Bernoulli beam theory and solved by the modal superposition method. The Duhamel Integral technique is used to evaluate the dynamic response. A parametric study demonstrates how external forces may affect the global wave induced vertical bending moments and shear forces. Numerical simulations are compared against a hybrid method that combines computational fluid dynamics, boundary element and finite element methods for low to medium frequency induced dynamic response. It is concluded that the proposed semi analytic methodology is fast and accurate and may be useful at concept ship design stage.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-17T08:59:55Z
  DOI: 10.1177/14750902231165808
Composite anti-disturbance control for ship dynamic positioning systems
with thruster faults
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  Authors: Ziwen Yu, Xinjiang Wei, Huifeng Zhang, Xin Hu, Jian Han
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Anti-disturbance control problem is studied for ship dynamic positioning systems with model uncertainties and ocean disturbances under thruster faults. For the ocean disturbance, a stochastic disturbance observer (SDO) is established to give the online estimation. For thruster faults, an adaptive law is used to evaluate, which is obtain from Lyapunov function. For model uncertainties, a robust control term with adaptive technology is used to attenuate it. Then, a composite anti-disturbance control (CADC) strategy is raised by combining disturbance observer-based control (DOBC), adaptive technology, and robust control term, which makes the position and yaw angle of ship reach the desired values. Finally, the simulation example proves the validity of the controller.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-15T06:14:24Z
  DOI: 10.1177/14750902231167073
Virginia tech advanced towing carriage
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  Authors: Christine Gilbert, Mohammad Javad Javaherian, Craig Woolsey, Mark Shepheard
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Virginia Tech has recently acquired a new towing carriage and vertical planar motion mechanism. The new towing carriage replaces the original carriage that was installed in the 1960s. The original carriage had a maximum speed of roughly 3 m/s, and the new carriage has a maximum speed of 7 m/s with the current wavemaker installation. The towing tank facility is used for both teaching and research activities in ocean engineering. The vertical planar motion mechanism includes two linear actuators to change the pitching and heaving behavior of a surface or subsurface test article to model different phenomena such as slamming or porpoising of surface vessels and vertical plane maneuvers for subsurface vessels. The focus of this paper is on the determination of the specifications for the towing tank to meet both teaching and research needs and the early resistance experiments that have been conducted during initial shake-down of the new facility. The authors will discuss how preliminary resistance experiments compare to the USNA towing tank facility.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-13T10:41:09Z
  DOI: 10.1177/14750902231166958
Energy-specific greenhouse gas emissions measurements from 2-stroke marine
diesel engine using liquefied natural gas
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  Authors: Kang-Ki Lee, Wilfried Hochegger, Alessandro Schönborn
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This study reports the energy specific air emissions from a diesel-cycle high pressure injection dual fuel engine for operation on liquefied natural gas and heavy fuel oil. An experiment at sea was performed onboard a bulk carrier during commercial voyages, to measure the efficiency of the engine and to measure air emissions relevant to air pollution and climate impact for operation on both fuels. The measurements showed that the energy conversion efficiency of the engine was higher for operation on liquefied natural gas because its lower NOx emissions permitted the use of a higher effective compression ratio whilst meeting the same NOx emissions level. The results showed that the climate impact for operation on heavy fuel oil was 2.1–2.3 times higher than for liquefied natural gas at 50% load, if considering only the emissions occurring at the engine. Analysis of the air emissions for their individual contributions to climate impacts suggested that black carbon had the strongest climate impact of all air emissions in the case of operation on heavy fuel oil. For operation on liquefied natural gas, CO2 had the strongest individual climate impact amongst the air emissions from the engine.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-13T10:39:39Z
  DOI: 10.1177/14750902231166442
On the use of Fourier Features-Physics Informed Neural Networks (FF-PINN)
for forward and inverse fluid mechanics problems
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  Authors: Omar Sallam, Mirjam Fürth
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Physics Informed Neural Networks (PINN), a deep learning tool, has recently become an effective method for solving inverse Partial Differential Equations (PDEs) where the boundary/initial conditions are not well defined and only noisy sparse measurements sampled in the domain exist. PINN, and other Neural Networks, tends to converge to the low frequency solution in a field that has multiple frequency scales, this is known as spectral bias. For PINN this happens when solving PDEs that exhibit periodic behavior spatially and temporally with multi frequency scales. Previous studies suggested that Fourier Features-Neural Networks (FF-NN) can be used to overcome the spectral bias problem. They proposed the Multi Scale-Spatio Temporal-Fourier Features-Physics Informed Neural Networks (MS-ST-FF-PINN) to overcome the spectral bias problem in PDEs solved by PINN. This has been evaluated on basic PDEs such as Poisson, wave and Gray-Scott equations. In this paper we take MS-ST-FF-PINN a step further by applying it to the incompressible Navier-Stokes equations. Furthermore, a comparative analysis between the PINN and the MS-ST-FF-PINN architectures solution accuracy, the learnt frequency components and the rate of convergence to the correct solution is included. To show this three test cases are shown (a)-Forward time independent double-lid-driven cavity, (b)-Inverse time independent free surface estimation of Kelvin wave pattern, and (c)-Inverse 2D time-dependent turbulent Von Karman vortex shedding interaction downstream of multiple cylinders. The results show that MS-ST-FF-PINN is better at learning low and high frequency components synchronously at early training iterations compared to the PINN architecture that does not learn the high frequency components even after multiple iteration numbers such as the Kelvin wave pattern and the Karman vortex shedding cases. However, for the third test case, the MS-ST-FF-PINN architecture showed a discontinuity for the temporal prediction of the pressure field due to over-fitting.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-13T10:25:45Z
  DOI: 10.1177/14750902231166424
Assessment of percent-time-operable of surface combatants with
conventional and wave-piercing hulls
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  Authors: Sungeun Choi, Kiwon Kim, Hoyong Kim, Jeonghwa Seo, Kyung-Kyu Yang, Shin Hyung Rhee
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  The present study concerns assessing and comparing the operability of two surface combatants with conventional and modern wave-piercing hulls. The operability is measured in terms of the percent-time-operable (PTO), based on the capability of missions in the annual operating condition by seakeeping analysis. The seakeeping criteria of the surface combatant in various missions are selected by the literature review applicable to the basic design stage. The numerical seakeeping analysis is performed to obtain ship motion spectra in seaways around the Korean peninsula and North Pacific, after corrected by comparison to the experiments in regular waves. It is found that the wave-piercing hull has higher PTO than the flared hull under a generic operation scenario owing to reduced pitch motion and low resonance frequency of roll motion, the main restraint of seakeeping performance in PTO assessment.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-07T05:05:00Z
  DOI: 10.1177/14750902231166429
A risk assessment of scrubber use for marine transport by rule-based fuzzy
FMEA
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  Authors: Çağlar Karatuğ, Bulut Ozan Ceylan, Yasin Arslanoğlu
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  To comply with the International Maritime Organization’s sulfur regulations, shipping companies have mainly favored scrubber systems. Even though the ship’s operations might be continued provided regulatory constraints are followed, the installation presents system-based risks depending on the scrubber type. This study’s primary aim is to inform the shipping industry about the risks associated with various scrubber applications on ships and to propose guidelines to ensure safer scrubber operation on marine vessels. Consequently, a risk evaluation is conducted on all kinds of scrubber systems. Experts in the marine industry identify the main subsystems and components and evaluate their failure modes and consequences. Using the fuzzy failure modes and effects analysis method, the acquired judgments are analyzed. The risk value of each failure scenario is computed using the Mamdani fuzzy inference technique and the evaluation of expert ratings. The riskiest failure modes identified by the investigation include the sensing element, injection nozzles, packed peds, and seawater system valves.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-04-04T05:54:13Z
  DOI: 10.1177/14750902231166030
Research on propeller cavitation wake characteristics based on
multivariate statistical modeling method
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  Authors: Kun Zhou, Zhifeng Zhu, Bing Wang, Fang Zhou
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  The radiation noise generated by cavitation has been extensively studied for underwater target recognition, but there are few reports on the related mechanism of the cavitation noise of ship propellers that attract attention in the field of hydroacoustics. In this paper, the RANS equations of the underwater propeller wake field are constructed, and numerically solved by combining the cavitation model and the turbulence model. The power spectrum is used to analyze the signal of the numerical calculation results of the propeller wake pressure. The feature estimation and extraction are carried out to obtain the characteristic values of the specific characteristic parameters. These eigenvalues not only reflect the flow field characteristics but also the geometric parameters and working conditions of the propeller. Therefore, two models are established around the relationship between them. Firstly, these eigenvalues are used for regression analysis in multivariate statistics to obtain a statistical model reflecting the characteristics of propeller cavitation wake. Secondly, the relationship between the propeller skew angle and the low frequency linear spectrum amplitude is obtained by using the power spectrum diagram. In this paper, the processing results of the experimental data of the cavitation water tunnel with controllable parameters and the radiation noise data of the actual target are used to verify and supplement each other with the processing results of the feature model.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-30T05:21:52Z
  DOI: 10.1177/14750902231164789
Numerical and experimental investigation of the quasi-cavitation effect on
a ducted Propeller for ROV
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  Authors: Li Zhandong, Ma Shuang, Tao Jianguo, Li Jingkui, Wang Wei, Wei lina
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  To control precisely and investigate maneuverability of an underwater vehicle in a nuclear power pool this article presents a study on the mathematical model and the thrust characteristics of a ducted propeller under the quasi-cavitation effect by a numerical method. Firstly, a mathematical model of a ducted propeller including the quasi-cavitation effect term which is often ignored, is established based on the thrust performance under different quasi-cavitation distances and the revolution speed by CFD. Then the pressure field near the suction and pressure surface of blades are analyzed, which reveals that the thrust increases with a decrease of the quasi-cavitation distance. Finally, the thrust performances under different conditions are experimentally measured in an open-water pool, which can verify the reliability of the mathematical model below the error of 10%. The results demonstrates that the presented method can be used to evaluate the dynamic mechanism of a propeller, and hold a potential to improve the control strategy.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-28T11:02:21Z
  DOI: 10.1177/14750902231163905
A mathematical study of water wave interaction with a thin perforated
barrier in a two-layer fluid over a permeable bottom
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  Authors: Koushik Kanti Barman, Swaroop Nandan Bora
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This article studies the impact of a submerged interface-piercing perforated barrier in a two-layer fluid flowing over a permeable bottom. We investigate oblique wave scattering, trapping and radiation due to the structure focusing on the bottom permeability. The dead water phenomenon is analysed with the consideration of the bottom permeability, which results in a higher variation of the interfacial wave due to the bottom permeability. The matched eigenfunction expansion method and the least square technique are used to calculate various hydrodynamic coefficients. Wave energy identity relation is derived for the scattering scenario, and the associated energy loss due to the barrier is calculated. In order to attain the maximum wave dissipation, an ideal porous-effect parameter of the barrier is proposed for consideration, and it is observed that larger values of porous-effect parameter result in the lowest feasible pressure distribution. A good comparison with a prior result justifies the current semi-analytical procedure. Furthermore, the verification of the energy-identity terms aid in the validation of the computed results. Additionally, wave trapping in a confined region is examined by investigating reflection coefficients by considering a rigid wall. The thin perforated barrier model is further considered for examining the radiation aspect while considering its slow motion. For various porous-effect parameters of the barrier, the amplitude ratio of the radiated potential is investigated, and it is clearly observed that higher frequency significantly lowers the amplitude for both free surface and interfacial propagating modes. The impact of the perforated barrier is analysed by investigating the essential hydrodynamic coefficients, namely, added mass and damping coefficient.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-22T11:55:33Z
  DOI: 10.1177/14750902231161120
Hindcast of oil spill pollution in the East China Sea in January 2018
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  Authors: Thi-Hong-Hanh Nguyen, Tien-Hung Hou, Hai-An Pham, Chia-Cheng Tsai
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  In this study, an integrated model is developed for studying the Sanchi oil spill event, which occurred in the East China Sea in January 2018. The results of the Advanced Research Weather Research and Forecasting model (WRF-ARW) as well as the Princeton Ocean Model (POM) are used for meteorological forecasting and the hydrodynamic simulations, respectively. These data are adopted as inputs for the OpenOil, a sub-module of OpenDrift, for the oil spill model. Some reference experiments are examined for short-term hindcast. The satellite image is used to validate the numerical result. The oil slicks of the satellite image and the numerical result are of similar shapes. Quantitatively, the simulated oil slick and that from the satellite image are located closely and have similar dimensions of 56 km by 34 km and 54 km by 29 km, respectively. It is found that the accurate results can be obtained by the proposed integrated model with the high-frequency (hourly) and high-spatial-resolution data as inputs, and the wind drift factor has to be added. The long-term 1-month simulation showed that most of the oil particles would move to the northeast of the sinking location and be trapped by the Kuroshio current.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-20T10:27:47Z
  DOI: 10.1177/14750902231162171
A deep learning method for the prediction of 6-DoF ship motions in real
conditions
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  Authors: Mingyang Zhang, Ghalib Taimuri, Jinfen Zhang, Spyros Hirdaris
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This paper presents a deep learning method for the prediction of ship motions in 6 Degrees of Freedom (DoF). Big data streams of Automatic Identification System (AIS), now-cast, and bathymetry records are used to extract motion trajectories and idealise environmental conditions. A rapid Fluid-Structure Interaction (FSI) model is used to generate ship motions that account for the influence of surrounding water and ship-controlling devices. A transformer neural network that accounts for the influence of operational conditions on ship dynamics is validated by learning the data streams corresponding to ship voyages and hydro-meteorological conditions between two ports in the Gulf of Finland. Predictions for a ship turning circle and motion dynamics between these two ports show that the proposed method can capture the influence of operational conditions on seakeeping and manoeuvring.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-11T09:39:03Z
  DOI: 10.1177/14750902231157852
Parameter sensitivity of the excessive acceleration failure mode in
second-generation intact stability
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  Authors: Kyung-Kyu Yang
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  In this study, the parameter sensitivity of the level 1 and 2 assessments of the excessive acceleration failure mode in the International Maritime Organization second-generation intact stability was analyzed. Monte-Carlo simulations were conducted using the input parameter space, which was generated using a Gaussian distribution, and a variance-based sensitivity analysis was performed using the Monte-Carlo simulation results. The longitudinal and vertical positions of the check point, natural roll period, and roll decay coefficient were selected as input parameters for the level 1 assessment, whereas the roll damping coefficient and effective wave slope coefficient replaced the roll decay coefficient for the level 2 assessment. The results revealed that the highest total sensitivity index for the level 1 assessment was the natural roll period, which was 0.8, and the effective wave slope had a total sensitivity index of 0.5 for the level 2 assessment. This indicated that the uncertainty of the natural roll period was dominantly propagated to the resultant value of the level 1 assessment, while the effective wave slope coefficient was the most sensitive parameter in the level 2 assessment. The uncertainty in the input variable was found to cause the opposite decision if the resultant value was close to the criterion value under a given loading condition.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-04T10:27:50Z
  DOI: 10.1177/14750902231157850
Analytical calculation method for predicting contact loads and structural
strength of metallic gasket of subsea connectors under thermal loads
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  Authors: Kang Zhang, Huarong Cheng, Junpeng Liu, Haining Wang
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Identifying the effect of thermal loads that are caused by temperature differences of inner and outer fluids on the structural sealing performance and strength is a long-standing quest in the design of subsea connectors. However, the structural stress and sealing parameters of the gasket under thermal loads are difficult to analyze and calculate using the current theoretical method because the boundary conditions of the gasket’s geometry surface are contact constraints interacted by the gasket and hubs. This paper presents an analytical calculation method (ACM) that evaluates the thermal-structural coupling strength and sealing performance considering such special boundary conditions. The thermal load is converted into an equivalent compression load, that is, a concentrated force, and applied to the contact region of the gasket. Additionally, a thermal-structural coupling finite element model is proposed to verify the ACM and the results show good agreement. Taken together, this work contributes to the design of subsea connectors that more likely take thermal loads into account.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-03-01T07:16:45Z
  DOI: 10.1177/14750902231157808
Investigation on innovative pile head breakwater for coastal protection
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  Authors: Arunakumar Hunasanahally Sathyanarayana, Praveen S. Suvarna, Pruthviraj Umesh, Kiran G Shirlal
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Coastal erosion is a global concern that has been augmenting due to the natural evolution of beaches, human activities and sea-level rise. One of the eco-friendly shore protection methods is to dissipate the wave energy by constructing offshore breakwaters. Conical pile head breakwater (CPHB) is one of the eco-friendly innovative offshore structures consisting of closely spaced piles with an enlarged cross-sectional area (conical pile head) in the vicinity of the free surface. In the present study, perforations are incorporated over the conical pile head to achieve higher efficiency by promoting energy dissipation. The influence of the perforations on the performance characteristics, namely wave transmission (Kt), wave reflection (Kr) and energy dissipation (Kd) of the perforated CPHB is comprehensively investigated through physical model studies. The effect of perforations and their distribution around the pile head (Pa), percentage of perforation (P) and size of perforations (S/D) on the wave attenuation characteristics are evaluated to arrive at an optimum configuration. The study is carried out under monochromatic waves of varying wave height (0.06–0.16 m) and wave period (1.4–2 s) at different depths of water (0.35, 0.40 and 0.45 m). A minimum Kt of 0.58 associated with Kr of 0.26 and Kd of 0.78 is obtained with an optimum configuration of Pa = 50%, P = 19.2% and S/D = 0.25. The Kt of the proposed CPHB is about 19 to 35% lesser than that of the perforated hollow pile breakwater under matching test conditions. Overall, providing the perforations is found to be effective in enhancing the wave attenuation capability by up to 12.4%. Further, empirical equations are formulated and validated with the experimental data. The empirical equations estimate the Kt and Kr values accurately with a high coefficient of determination (R2 ≥ 0.90).
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-02-22T12:46:15Z
  DOI: 10.1177/14750902231155677
AxV: An autonomous vehicle concept capable of operating throughout the
ocean space: air, surface and subsea
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  Authors: James Bowker, Mingyi Tan, Nicholas Townsend
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This paper presents a concept design for an Autonomous Vehicle (AxV) capable of operating throughout the ocean space; air, surface and subsea. With current autonomous platforms limited in their operation, for example aerial platforms only operate in air, ASVs only operate on the ocean surface and AUVs operate subsea, a platform which can operate, transiting and transitioning in and between air, surface and subsea, providing increased mobility is very attractive. In this paper, a novel AxV platform is described. The governing equations are presented, describing each operational mode and the transitions between modes (air to surface, surface to subsea, subsea to surface, surface to air). Results are presented based on the dimensions of existing vehicles, showing that the system is theoretically feasible.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-02-03T12:14:57Z
  DOI: 10.1177/14750902221150285
A literature review and future research agenda on fault detection and
diagnosis studies in marine machinery systems
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  Authors: Muhittin Orhan, Metin Celik
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Fault detection and diagnostics (FDD) have great potential to enable safety, efficiency, and reliability measures of critical machinery systems. However, it is clear that there is a lack of systematic literature review to identify and classify the FDD studies conducted within the scope of marine engineering. This paper offers a systematic review of FDD models particular to marine machinery and systems. The numbers of 72 core articles were highlighted through a comprehensive literature review conducted in the 2002–2022 period. The studies are classified based on the mostly utilized methods such as data-driven, model-based, knowledge-based, and new generation-hybrid. In addition, new generation and hybrid methods are discussed in detail. The experimental environment (i.e. shipboard, labs, simulator) and technical details of the conducted studies are extensively discussed. While 56.94% of the examined studies are related to the main engine, 43.06% of them are related to auxiliary engines. In addition, the main and auxiliary engine studies are also divided into subject headings and examined in detail. Given the recent developments in green and smart maritime concepts, a future research agenda of the FDD studies on marine machinery systems is then pinpointed. Consequently, the study stimulates scholars interested in FDD while it enables innovative ideas for marine engineers, technology providers, ship operators, and maritime entrepreneurs.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-31T10:53:57Z
  DOI: 10.1177/14750902221149291
A study of the frequency response of fluid-structure interactions in a
three-dimensional fluid-filled pipe system using an impedance synthesis
method
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  Authors: Jiang-hai Wu, Zhi-yong Yin, Yu-dong Sun
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Fluid-filled pipelines are widely used in engineering and industry. An analysis of the frequency dynamic responses of three-dimensional pipes is presented in this paper. A general formulation is developed based on an impedance matrix transmission approach in which a T-shaped pipe system can be assembled from three straight pipes. For validation purposes, numerical results are compared with data given by finite element method (FEM) software, previous literature, and an experiment. In the experiment, the three-dimensional pipe system is suspended horizontally on spring wires and is excited in the X and Y directions. It is found that the results calculated using the proposed method match the experimental results well. A dimensionless analysis of Poisson’s coupling is then carried out, and the junction coupling of the branch pipe is analyzed as a function of its angle. Through this work, it is shown that the proposed method is efficient and can be used to predict the vibration of three-dimensional pipes.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-31T10:43:37Z
  DOI: 10.1177/14750902231152337
Some relationships between build strategy and shipbuilding time in
European shipbuilding
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  Authors: Marco Semini, Clara Patek, Per Olaf Brett, Jose Jorge Garcia Agis, Jan Ola Strandhagen, Jørn Vatn
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  The build strategy of a ship specifies what is to be produced how, when, where and with what resources. Although it has been emphasised to play an important role in determining shipbuilding time and cost, scientific research on build strategy is limited. In this study, we focus on three interrelated build strategic factors of particular importance in European shipbuilding: hull production offshoring, pre-erection outfitting and the overlap between engineering and production. The study investigates how each of these three factors relates to physical ship production time and to total ship delivery time from contract signing to delivery. We use multiple linear regression on data about European shipyards and the ships they have built, which were obtained from a questionnaire and ship databases. The sample consists of 76 specialised ships, predominantly offshore support vessels, fishing vessels, ferries and other non-cargo carrying vessels, built at 24 European yards. The results provide evidence that yards practicing hull production offshoring have shorter ship production and delivery times than yards building the hulls at their own premises, even though the practice of offshoring itself is likely to have an adverse effect on shipbuilding time. The study also found a significant relationship between the level of pre-erection outfitting and physical production time. On the other hand, overlapping engineering and production only seems to have a limited impact on the production and the delivery time. Several of our results challenge established thinking and provide new insights into the factors affecting production and delivery time in European shipbuilding.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-28T09:21:22Z
  DOI: 10.1177/14750902221141749
Online maximization of extracted energy in sea wave energy converters
using temporal-difference learning
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  Authors: Sadegh Khaleghi, Reihaneh Kardehi Moghaddam, Mohammadbagher Naghibi Sistani
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This article presents temporal-difference (TD) learning which is a combination of Monte Carlo and dynamic programing (DP) as a Method for controlling single-body wave energy converters (WECs). Since TD methods are designed to solve the prediction problems, we use this feature to maximize the energy captured from the sea waves. The entered force to the buoy system is addressed implicitly in the state matrix to design the problem into a TD framework. In order to enhance the captured power by the WEC, the control method is built to have an online active control. This will help the device to predict the best controller based on its previous experiences in the same situations. Two methods of TD, Q-Learning and SARSA, are used and the features are analyzed and several testing functions are carried out in simulation part. To perform on-line optimal control, a force control has acted as a controller and TD coefficients are tuned at a proper rate significantly after specific number of episodes. The power of suggested TD methods is compared to PGM, IPOPT and with other learning control strategies. Several computer simulations were carried out to evaluate the controller effectiveness by applying different sea-states and analyzing the resultant WEC dynamics.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-27T09:25:10Z
  DOI: 10.1177/14750902221149468
Adaptive generalized predictive control for dynamic positioning system of
ships with model unknown parameters
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  Authors: Xin Hu, Zhongyu Sun, Rui Wang, Shuwen Feng
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This paper proposes an adaptive generalized predictive control for dynamic positioning of ships with unknown model parameters and unknown time-varying environmental disturbances. The controlled auto-regressive integrated moving average (CARIMA) model is employed to describe the movements of ships with model parameter and disturbance uncertainties. The recursive least square method with forgetting factor is utilized to design adaptive laws to estimate the CARIMA model parameters online. Considering both the positioning accuracy and the change intensity of control increments, a cost function is constructed. The optimal control increments that minimize the cost function are obtained by using Lagrange multiplier method. Then, the adaptive control law is designed to maintain ship’s position and heading at desired values. Finally, simulation studies in different cases are carried out and simulation results demonstrate the effectiveness of the proposed control scheme.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-27T09:10:12Z
  DOI: 10.1177/14750902221149078
A review of geographic information system (GIS) and techno economic (TE)
software tools for renewable energy and methodology to develop a coupled
GIS-TE software tool for marine renewable energy (MRE)
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  Authors: Ross O’Connell, Jimmy Murphy, Fiona Devoy McAuliffe, Gordon Dalton
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Accurate and up-to-date Geographic Information System (GIS) and Techno Economic (TE) tools are pertinent to helping to develop the renewable energy sector. This paper reviews the state of the art in existing GIS and TE tools for renewable energy and proposes a methodology to develop a coupled GIS-TE software tool that is geared specifically to Marine Renewable Energy (MRE) applications and bespoke to Irish and Western UK waters. Methods for approaching GIS and TE analysis within existing tools for renewable energy are presented and compared. Many existing tools of this nature have some interesting functionalities, but most are unsuitable for MRE; are limited by a lack of information on both the technology and the site; and focus solely either on GIS or TE aspects of analysis. Additionally, almost all of those with a TE focus are not open access. The proposed tool aims to incorporate increased resolution and site relevance of resource data; the most up-to-date geospatial data for site selection; and will provide site specific TE indicators and recommendations for contemporary MRE devices. The result will be the development an open-access GIS-TE software tool for MRE.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-23T06:14:51Z
  DOI: 10.1177/14750902221150050
Numerical analysis of the effect of the blade number on the hydrodynamic
performance of shaftless rim-driven thruster
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  Authors: Wen Jiang, Xin Shen, Liangliang Liu, Tao Bian
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  In this work, numerical investigations were performed to the study the effect of blade number on the hydrodynamic performance of shaftless Rim-driven Thruster (RDT) with certain blade area ratio and pitch ratio. The work investigated and compared the thrust coefficient, torque coefficient and efficiency of the RDTs with different blade numbers. Additionally, this work detected and analyzed the pressure distribution on the blade surface and velocity distribution around the blade and in the wake. The results demonstrate that for a certain advance coefficient, the thrust coefficient and torque coefficient of the RDT increase with the blade number, however the efficiency of the RDT decreases with the increase of blade number. For the same cross-section and advance coefficient, the 7-blade RDT has higher thrust and torque than the 3-blade RDT due to the large friction and pressure difference between the suction and pressure surfaces. The high velocity of both RDTs appears at the junction between each blade and the duct, and the 7-blade RDT has higher velocity in the wake and in the cross-section than the 3-blade RDT. The 3-blade RDT has the high pressure at the leading edge on the suction surface of each blade. However, the 7-blade RDT has not only the high pressure at the leading edge, but also the high negative pressure at the blade root on the suction surface of each blade, so 7-blade RDT has higher torque that 3-blade RDT.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-18T11:57:44Z
  DOI: 10.1177/14750902221145785
Study on influencing factors of hydrodynamics based on AUV docking with
conical dock
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  Authors: Jiayu Diao, Weimin Li, Xueqing Yuan, Kai Jiang, Yifeng Zhao
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  It is necessary to investigate the dynamic performance during autonomous underwater vehicle (AUV) underwater docking to aid in control and to enhance docking safety. Therefore, in this study, the docking hydrodynamic characteristics (including the docking system’s streamline, velocity vector, and surface pressure during the overall docking process) of the AUV with conical hood dock are determined by using the dynamic grid technology, and the water drag force situations of the AUV docking with conical hood dock are studied from the perspectives of different velocities, accelerations, navigation modes, and structures. Additionally, the multiple nonlinear regression fits and the preliminary docking test were examined. Furthermore, brief inferences obtained are as follows: First, the maximum pressure is situated at the upstream surface of the dock conical hood and the head of the AUV, and the maximum rotation angle of the streamline is situated at the outermost ring of dock conical hood. Within a specified range, the rotation angle of the streamline affected by the conical hood progressively declines as the AUV docks deeper into the conical hood. Second, low velocity uniform docking, deceleration docking, and chase docking can reduce the drag force to a certain extent during docking. Finally, both arc shape and mesh structure can decrease the water drag force of docking to a specified degree. This research provides a theoretical basis and reference methods for the dynamic research of the docking system, and other related research can be carried out through the methods and results of this research.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-16T06:19:22Z
  DOI: 10.1177/14750902221147623
Marine vessel powertrain design optimization: Multiperiod modeling
considering retrofits and alternative fuels
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  Authors: Antti Ritari, Janne Huotari, Kari Tammi
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  Over the coming decades, maritime transportation will transition from fossil hydrocarbon fuels to hydrogen, ammonia, and synthetic hydrocarbon fuels produced using renewable electricity as the primary energy source. In this context, a shipowner needs to identify a cost-efficient plan for the adoption of alternative fuels and onboard energy conversion system retrofits. This paper presents a multiperiod decision model for the selection of energy system components under increasingly stringent CO2 emissions regulations and cost forecasts over a multidecade planning horizon. The model considers the choice of newbuild architecture, timing of retrofits, component sizes, and allocation of fuels to converters with the objective of minimizing total cost of ownership (TCO). The decision problem is formulated as a discrete time multiperiod mixed-integer linear program. The application of the model is numerically illustrated for a Baltic Sea roll-on/roll-off ferry. The main findings are: (i) modifying the energy system with retrofits obtains 43% lower TCO compared to fuel switching alone; (ii) batteries contribute to 23% lower TCO; (iii) optimal component installation period can be shorter than their maximum lifetime; (iv) running an engine with hydrogen is favored over fuel cells and (v) hybrid propulsion is the key future-proofing design choice for short sea vessels.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-12T10:13:53Z
  DOI: 10.1177/14750902221145747
A computation effective singularity avoidance method for the underwater
manipulator with a non-spherical wrist
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  Authors: Tiantian Yu, Lifu Gao, Daqing Wang, Weibin Guo, Yue Zhang
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  In order to perform increasingly complex underwater tasks, we have designed a hydraulic underwater non-spherical wrist manipulator with a binocular vision system and a six-dimensional force sensor mounted behind the end-effector, which can improve the path accuracy and automation capabilities of the system. The system lays a foundation for the high precision and autonomous deep-sea operation and can improve its intelligence level. In this paper, we focus on solving the singularity avoidance problem of the hydraulic underwater manipulator for accurate control, and propose a computationally efficient singularity avoidance method to improve the path accuracy of the manipulator with the non-spherical wrist. Firstly, the singular configurations of the manipulator are analyzed. Secondly, the Jacobian is decomposed into sub-block matrices to obtain the singular factors according to the singular configurations. Thirdly, the singularities are avoided by the approximate damped reciprocal method. Theoretical analysis shows that the computation costs of the proposed method are only one-third to one-half of that of the traditional methods. The simulation results prove that the proposed method can largely improve the path accuracy of the manipulator with less computation costs, which shows that our method would have a certain significance in improving the precision and real-time response of deep-sea operations.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-11T10:42:16Z
  DOI: 10.1177/14750902221149308
Application of swarm intelligence for dynamic properties of moored
floating structures using two-dimensional fluid dynamic program
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  Authors: Sheikh Fakhruradzi Abdullah, Rabiei Mamat
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This paper presents a numerical investigation into interactions between oscillatory waves and moored floating structures by through applying Swarm Intelligence (SI). The effects of small and large incident waves placing a force on the obstacles were studied using two floating structures composed of a rectangle and a cage kind with taut-moored and slack-moored situations. The aforementioned problem was reduced to solve systems of sparse-nonlinear equations for surge, heave, and pitch responses, as well as mooring forces considering that there is a distorted wave motion due to the presence of the movable obstacle boundary. The particle swarm optimization (PSO) algorithm is proposed here to provide insight into computational intelligence factors affecting calculation results and efficiency. Besides that, a computational fluid dynamic (CFD) program is based on a full Navier-Stokes solver. A series of numerical examinations for selected wave heights and wavelengths including a set of optimization procedures have been taken into account in the evaluation of formulated objective function, F, where the best potential solution is computed at each computational step. Meanwhile, a collection of empirical benchmarks were also developed based on reported measurements in the literature to provide sound empirical support for the theoretical findings. The results show that the optimization method exhibits a favorable convergent behavior (F≈0), where the computed results agree well with the measurements in terms of mean amplitudes of the surge, heave, and pitch responses and peak values of mooring-line tensions. The approach would firmly converge on benchmarks with improved computational steps of 18,321 running for 20.1 wave cycles in the case of the taut-moored rectangular structure. For the slack-moored cage, a satisfactory convergence was achieved using a series of data calibrations into an algorithm that took 27,976 iterations and 24.5 s to complete. Furthermore, CFD captures of wave deformations, dynamic forces, and streamlines were able to qualitatively corroborate the results.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-04T12:59:28Z
  DOI: 10.1177/14750902221143596
Prediction of the maneuvering behavior of a containership in a seaway
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  Authors: Ahmad Darvish Bachari, Ahmad Hajivand, Mehdi Hasani
  Abstract: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, Ahead of Print.
  This study investigated the turning maneuver performance of a containership in regular waves using a two-time scale formulation. This article also presents a ship motion program, coupled with a 3-degree of freedom (3-DOF) maneuvering solver, whereby the seakeeping problem is solved with the forward speed considered in the computations. Captive tests were simulated in a computational fluid dynamics (CFD) environment to obtain the maneuvering derivatives. A near-field analysis was performed to obtain the effective wave force, which was the second-order mean drift force in this analysis. The proposed method was used to estimate the turning circle maneuver performance of the S-175 containership in both calm water and waves of different wavelengths. Ultimately, the simulation results showed high consistency with experimental data.
  Citation: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
  PubDate: 2023-01-04T12:57:28Z
  DOI: 10.1177/14750902221143255