{"title":"Dynamic Response Analysis of Offshore Flaoting Hose Strings Under Wave Load","authors":"C. An, D. Zhao, Y. Gao, Y. Yang, T. Li","doi":"10.5750/ijme.v164ia4.1249","DOIUrl":"https://doi.org/10.5750/ijme.v164ia4.1249","url":null,"abstract":"A floating hose is key item for offshore oil transportation. In this paper, a mathematical model is derived for the overall dynamic performance of a single point-moored floating hose string under wave and current load. Airy wave theory was selected to calculate the wave force on the floating hose string. The dynamics of buoy, floating hose string and FSO were modelled using elastic foundation beam theory and discretised by using a fixed grid finite difference method. Discontinuities in the bending stiffness due to the flange connections are also considered. To verify the accuracy of the mathematical model, the finite element model of the buoy, floating hose string and FSO as a system was established by use of Orcaflex software tool. Numerical results for the displacement and bending moment at each section of the floating hose under severe sea conditions were obtained.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46567943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"THE CONCEIVE DESIGN IMPLEMENT OPERATE (CDIO) INITIATIVE - AN ENGINEERING PEDAGOGY APPLIED TO THE EDUCATION OF MARITIME ENGINEERS","authors":"J-B R G Souppez, T. Awotwe","doi":"10.5750/ijme.v164ia4.1187","DOIUrl":"https://doi.org/10.5750/ijme.v164ia4.1187","url":null,"abstract":"The Conceive Design Implement Operate (CDIO) initiative is an innovative engineering education framework aiming to produce industry-ready graduates. Over the past two decades, the approach has been increasingly popular, particularly in the mechanical engineering field, thanks to its practical approach and outcome-based assessments. However, the CDIO approach remains absent from the pedagogical tools employed in marine engineering education curricula. This paper argues that, although unrecognized as such, modern marine engineering courses have been employing an approach akin to that of the CDIO initiative. Four international case studies, in both undergraduate and postgraduate higher education, are employed to demonstrate that the marine engineering courses under consideration indeed utilize the CDIO approach to engineering education. Furthermore, this paper identifies the CDIO initiative as a relevant pedagogy for the development of novel marine engineering courses and activities. It is anticipated that this first recognition of the use of the CDIO initiative in marine engineering education will contribute to formalizing the implementation of the CDIO initiative in this field, as well as enable greater synergies between the various disciplines of engineering education.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47283292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"MARINER 4.0: INTEGRATING SEAFARERS INTO A MARITIME 4.0 ENVIRONMENT","authors":"N. Taylor, A. Bekker, K. Kruger","doi":"10.5750/ijme.v164ia4.773","DOIUrl":"https://doi.org/10.5750/ijme.v164ia4.773","url":null,"abstract":"Digitalisation of systems and processes in the maritime industry are spurring Maritime 4.0, a digital transformation promising enormous gains, including improved design processes and reduced operational costs. Gleaning inter-disciplinary proficiency from Operator 4.0 in manufacturing, the present work seeks to introduce the Mariner 4.0 – a seafaring passenger or crew member with technologically augmented skills. This research aims to realise Mariner 4.0 through a human digital twin solution – a virtual representation of the state and behaviour of a unique individual over time – for seafarers on South Africa’s polar research and supply vessel, the SA Agulhas II. This paper presents human-related challenges identified within seafaring vessels, the expected value of human digital twin solutions for the maritime industry, the development of a human digital twin solution to integrate seafarers into a Maritime 4.0 environment (i.e. the development of Mariner 4.0), and an illustrative use case focussing on human comfort monitoring and management.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45317552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"STATE-OF-THE ART IN COMPUTATIONAL ANALYSIS OF CAVITATION INCEPTION AND ITS SCALE EFFECTS","authors":"E. Amromin","doi":"10.5750/ijme.v164ia4.814","DOIUrl":"https://doi.org/10.5750/ijme.v164ia4.814","url":null,"abstract":"Mathematical analysis of cavitation inception is an important topic for naval engineering, but several circumstances make it difficult. First, cavitating flows are substantially multi-zone flows, where the appearing cavities are incomparably smaller than a cavitating body is. Second, inception is substantially influenced by characteristics of the inflow and of the body surfaces. Third, validation of employed mathematical methods by comparison with experimental data is a non-trivial task because of the complexity of experiments themselves and scale effects. This paper is emphasized on multi-zone quasi-steady approaches for prediction of cavitation inception and desinence numbers. The obtained computational results are compared with the known experimental data for sheet cavitation, vortex cavitation and cavitation behind surface irregularities. Procedures of scaling of cavitation inception number and the eventual combinations of various CFD solvers are also discussed.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48246590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"AN EXPERIMENTAL STUDY ON ADDED MASS COEFFICIENT OF VORTEX-INDUCED VIBRATION OF A CIRCULAR CYLINDER","authors":"J. Gu","doi":"10.5750/ijme.v164ia4.817","DOIUrl":"https://doi.org/10.5750/ijme.v164ia4.817","url":null,"abstract":"In this paper, an experiment study with aspect ratio 100 of a circular cylinder was conducted in a wave-current channel. The FBG sensors were attached on the circular cylinder which are used to capture vibration signal, two high-precision bellows type sensors were used to monitor fluctuant support force, and the dynamic response of circular cylinder was finally calculated by modal analysis method. The effect of flow velocity, mass ratio and top tension of circular cylinder on the amplitude ratio, frequency ratio and added mass coefficient was evaluated. The results showed that top tension had a greater influence on the amplitude; the added mass coefficient demonstrated a nonlinear relationship with external flow velocity. The added mass coefficient decreases when the reduced velocity increases. At a particular reduced velocity, the added mass coefficient decreases when the top tension increases or mass ratio increases. ","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45057050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"EARLY STAGE DECISIONS IN MARINE SYSTEMS DESIGN FOR DEEP-SEA MINING","authors":"","doi":"10.5750/ijme.v164ia4.771","DOIUrl":"https://doi.org/10.5750/ijme.v164ia4.771","url":null,"abstract":"This article studies the prospects for deep seabed mining as a future viable maritime industry, and discuss the commercial, operational, and technical viability of deep seabed mining. By the use of a business development approach originating from the maritime industry, we analyse opportunities for a virtual deep seabed mining project, and identify aspects of stakeholder performance expectations, contextualised by the competitive positioning and identification of related project risks. We discuss strategies and pit-falls when positioning a deep seabed mining venture within the wider mining and metal production value chain, and use a case example in the Northern Atlantic Ocean to study the prospects for a deep seabed mining operation and subsequent system design implications. Furthermore, we contrast to well-established industries like offshore oil and gas, and traditional land-based mining. The study promotes several critical aspects and problem areas when approaching marine systems design for deep seabed mining.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44828264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. M. Wang, X. Y. Chen, H. M. Yu, L. Chen, T. Wang, J. R. Xu, X. Wang
{"title":"NUMERICAL SIMULATION OF THE VISCOUS FLOW AROUND SHIPS TURNING IN SHALLOW WATER","authors":"H. M. Wang, X. Y. Chen, H. M. Yu, L. Chen, T. Wang, J. R. Xu, X. Wang","doi":"10.5750/ijme.v164ia3.1242","DOIUrl":"https://doi.org/10.5750/ijme.v164ia3.1242","url":null,"abstract":"Due to the effect of water depth, hydrodynamic characteristics of ships manoeuvring in shallow waters are quite different from those in deep water. In the present study, the CFD method is used to investigate the hydrodynamic behaviour of the ESSO OSAKA model in model-fixed condition in deep and shallow waters by solving RANS equations, which performs steady turning motion with the effect of free surface considered. The governing equations are discretized by the finite volume method (FVM) and the free surface is captured by applying the volume of fluid (VOF) method. Viscous hydrodynamic characteristics and flow fields in a series of cases at different water depths and speeds are investigated respectively. By comparing the numerical results in shallow water with those in deep water, it was found that effects of water depth and free surface are significant on ship’s hydrodynamic forces. The coefficients of drag, lateral force and yaw moment all increase with the decrease of water depth. The drag coefficient in shallow water is about 45% larger than that in deep water. However, effect of water depth on the lateral force coefficient is small, it is about 15% larger in shallow water than that in deep water. While, it has significant effect on the yaw moment coefficient, which is about 25% larger in shallow water than in deep water. And as the water depth increases, the effect of the free surface gradually becomes smaller. Both coefficient of pressure component of drag force and drag coefficient in the present simulation are about 7% smaller than the case without considering the free surface at h/d ≥ 3.0, while that of frictional component is almost the same. When h/d ≥ 3.0, the lateral force and yaw moment coefficients are almost the same as when the free surface is not considered. The error between the present numerical result and the measurements is within 10%, which indicates that RANS method has promising capability to predict the hydrodynamic forces on ships manoeuvring in shallow water.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46239592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Kılıç, Utku Cem Karabulut, Emrah Akdamar, L. Bilgili
{"title":"DETERMINATION OF NOX EMISSION FACTOR FOR DIESEL ENGINES OF RECREATIONAL BOATS BY ON-BOARD MEASUREMENT","authors":"A. Kılıç, Utku Cem Karabulut, Emrah Akdamar, L. Bilgili","doi":"10.5750/ijme.v164ia3.784","DOIUrl":"https://doi.org/10.5750/ijme.v164ia3.784","url":null,"abstract":"In this study, NOx emissions from diesel engines of 75 recreational boats were measured on-board in accordance with the simplified method specified in the NOx Technical Code. The study was carried out in boats with ranging between 14.42 m-37.50 m in length and engines power varying between 138 kW–2,040 kW. NOx emissions were measured by using a portable exhaust gas analyser (Testo 350 Marine) in ppm in a dry basis. An in-house program was developed to calculate the final emission results in g/kWh. The main aim of the study is to develop NOx emission factors for recreational boats, which are not specifically included in previous emission factor studies. The NOx emissions of the marine diesel engines of the recreational boats were found in range of 0.92 g/kWh – 10.69 g/kWh while the mean emission factor was found as 4.81 g/kWh.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42373575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mia Elg, Timo Korvola, B. Molchanov, Lien Tran, J. Lappalainen
{"title":"Improving ship sustainability by re-using engineering simulators in multi-objective optimization","authors":"Mia Elg, Timo Korvola, B. Molchanov, Lien Tran, J. Lappalainen","doi":"10.5750/ijme.v164ia3.1164","DOIUrl":"https://doi.org/10.5750/ijme.v164ia3.1164","url":null,"abstract":"Alternatives for enhancing a cruise ship’s energy efficiency were investigated by introducing different waste heat recovery technologies and battery systems in the machinery. A ship designer’s in-house ship energy system simulator was applied in a cloud-based framework for simulation-based optimization. This multi-objective optimization with economic and environmental objectives used genetic algorithm for finding the best overall solution in a complex ship energy system design task. The results suggest that adding battery capacity alone contributes very moderately to reducing the case ship fuel consumption and, therefore, carbon emissions. Nevertheless, a combination of steam turbines and organic Rankine cycle units would offer the largest fuel saving potential with the lowest investment cost in the case setup. Also, the main engines’ running hours were of interest. The presented approach can bring significant added value for sustainable ship design with minimal additional effort.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43785678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"AN OPTIMISATION PROCEDURE FOR PROPELLER SELECTION FOR DIFFERENT SHAFT INCLINATIONS","authors":"M. Tadros, M. Ventura, C. Guedes Soares","doi":"10.5750/ijme.v164ia3.809","DOIUrl":"https://doi.org/10.5750/ijme.v164ia3.809","url":null,"abstract":"In this paper, a propeller optimization model is presented to find the optimum propeller geometry and the gearbox ratio for different angles of the propeller shaft while minimizing the amount of fuel consumed at a given speed and complying with the proposed constraints' limitations. The developed model couples several simulation software where application programming interface (API) facilitates data processing to achieve the optimum design based on optimization procedures. A fishing vessel is selected as a case study to perform the numerical simulation. A comparison study is conducted between the optimized propellers at different inclination angles of the propeller shaft among different propeller blades. Bar chart and box and whisker plot are the two techniques considered to visualize the computed data. The results conclude that the optimized propeller with a high number of blades and a small inclination angle (2 degrees) can operate at the engine operating point as in a horizontal propeller shaft, which is considered the most efficient from the theoretical point of view.","PeriodicalId":50313,"journal":{"name":"International Journal of Maritime Engineering","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46975378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}