International Journal of Naval Architecture and Ocean Engineering最新文献

{"title":"Experimental investigation on wave characteristics due to interference of catamaran demi-hulls in waves","authors":"Thi Loan Mai ,&nbsp;Anh Khoa Vo ,&nbsp;Aeri Cho ,&nbsp;Van Thuan Mai ,&nbsp;Hyeon Kyu Yoon","doi":"10.1016/j.ijnaoe.2024.100594","DOIUrl":"10.1016/j.ijnaoe.2024.100594","url":null,"abstract":"<div><p>The presence of twin hulls of a catamaran has a strong impact on wave pattern in the whole inner region due to interference between waves generated by each demi-hull. Consequently, wave profiles as well as wave height become complicated and unpredictable in the inner region not only in still water, but also in the presence of waves. Determining wave characteristics between demi-hulls of the catamaran is essential for predicting the operation of an autonomous underwater vehicle (AUV) throughout the launch and recovery (LAR) process. This study performed an experiment to investigate wave characteristics between demi-hulls of the catamaran under regular and irregular waves at various wave directions and speeds. The experiment was designed to measure wave elevation in the inner region between demi-hulls in waves using ultrasonic sensors and capacitance wave probes. The experimental method and setting were verified exacting by comparing the motion response of the catamaran measured by the Qualisys system with numerical simulation using the 3D panel method. Then, wave elevation in the inner region was measured and analyzed to wave height which is a representative parameter of regular waves and to wave spectral density and significant wave height which are representative parameters for irregular waves. These parameters were compared to those of the ocean waves to understand influences of wavelengths, sea states, wave directions, and speeds on wave characteristics between demi-hulls of the catamaran. Plotting of difference from ocean waves indicated the discrepancy in wave characteristics among positions in the inner region, wavelengths, wave directions, sea states, and speeds compared to ocean waves. Results of wave characteristics in the inner region are valuable to analyze motion response and behavior of AUV during LAR process of unmanned surface vehicle (USV).</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100594"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S209267822400013X/pdfft?md5=ededaf9efc0e6dc3376a5b1ed4240b89&pid=1-s2.0-S209267822400013X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141035414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the performance impact of soft constraint integration on reinforcement learning-based autonomous vessel navigation: Experimental insights","authors":"Xin Jiang ,&nbsp;Jiawen Li ,&nbsp;Zhenkai Huang ,&nbsp;Ji Huang ,&nbsp;Ronghui Li","doi":"10.1016/j.ijnaoe.2024.100609","DOIUrl":"10.1016/j.ijnaoe.2024.100609","url":null,"abstract":"<div><p>Reinforcement learning has shown promise in enabling autonomous ship navigation, allowing vessels to adapt and make informed decisions in complex marine environments. However, the integration of soft constraints and their impact on performance in RL-based autonomous vessel navigation research remain understudied. This research addresses this gap by investigating the implications of soft constraints in the context of the risk-averse ship navigation problem. Four distinct soft constraint functions are proposed, which are integrated with two widely used RL algorithms, resulting in the creation of eight risk-averse autonomous vessel navigation models. To ensure a comprehensive evaluation of their performance, comparative analyses are conducted across seven virtual digital channel environments. Additionally, a novel metric, known as Large Helm Momentum (LHM), is introduced to quantify the smoothness of autonomous vessel navigation. Through thorough experimentation, key considerations for the design of soft constraint functions in the domain of autonomous ship navigation are identified. A comprehensive understanding of how different soft constraint functions influence autonomous driving behavior has been achieved. Key considerations for designing soft constraint functions in the domain of autonomous ship navigation have also been identified. Five principles, namely the constraint association principle, dominance of hard constraints, reward-balance principle, mapping requirement principle, and iterative improvement principle, are proposed to optimize the design of soft constraint functions for autonomous ship navigation, providing valuable guidance and insights.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100609"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000281/pdfft?md5=88e268ac351e4b2b9b7c1582b3e4b23b&pid=1-s2.0-S2092678224000281-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141852717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical study on the high-speed ship hydrodynamics influenced by an interceptor with varied angle of attack","authors":"Arfis Maydino Firmansyah Putra,&nbsp;Hiroyoshi Suzuki","doi":"10.1016/j.ijnaoe.2023.100566","DOIUrl":"10.1016/j.ijnaoe.2023.100566","url":null,"abstract":"<div><p>Efforts to improve the hydrodynamic performance of high-speed ships have been underway for a long time. There are different approaches, one of which is to take advantage of an interceptor. Conventionally, the interceptor blades are mounted vertically on the ship's bottom transom, oriented at a zero-degree angle of attack (<em>AoA</em>). This study comprehensively explores high-speed ships' hulls with and without interceptor configurations, encompassing both negative and positive <em>AoA</em> of the interceptor, conducted through experimental and numerical methods using a fully captive model. The interceptors are strategically positioned and configured. Each configuration was examined under varying <em>AoA</em> settings, with uniform interceptor depths and systematic trim angle adjustments. The Computational Fluid Dynamics (CFD) approach simulates the local flow dynamics around the hull, thoroughly analyzing resistance, pressure distribution, lift force, wave profile, and trim moment. The results indicate that interceptor placement near the keel with <em>AoA</em> adjustments significantly reduces hydrodynamic resistance, while <em>AoA</em> changes have limited impact in other positions. Lift force analysis shows interceptors improve lift compared to the bare hull, but this improvement is not linear across positions. Furthermore, it is observed that adjustments in <em>AoA</em> influence lift, with a negative <em>AoA</em> generally being considered favorable. In summary, carefully considering placement, <em>AoA</em>, and height-to-length ratio is necessary to maximize interceptor advantages.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100566"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678223000559/pdfft?md5=696dae3edb9be7fb8f876120b859b820&pid=1-s2.0-S2092678223000559-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139017529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental datasets of surface piercing propellers operating in open-water conditions","authors":"Jeongsoo Ha ,&nbsp;Jaeheon Kim ,&nbsp;Shin Hyung Rhee","doi":"10.1016/j.ijnaoe.2024.100625","DOIUrl":"10.1016/j.ijnaoe.2024.100625","url":null,"abstract":"<div><div>The present experimental datasets provide the open-water performance characteristics of surface-piercing propellers under various operating conditions. The open-water tests were conducted in a towing tank, considering various pitch ratios, immersion ratios, shaft inclination angles, and Froude numbers. The model propellers were of two different modified shapes of the Model-841-B with different pitch ratios. Thrust, torque, and efficiency were measured and calculated for each condition. A high-speed camera was used to observe the ventilated cavity around the propeller. The datasets included a detailed description of wedge-shaped support blocks to vary shaft inclination angles and a spray shield to eliminate the effects of spray on the data acquisition system under surface-piercing conditions. Descriptions were provided for a streamlined underwater casing and filming techniques designed to prevent the flow from affecting propulsion performance. The datasets can be used to enhance the understanding of the effects of operating conditions on the propulsion performance of surface-piercing propellers. The datasets will serve as benchmark data for predicting the open-water performance of surface-piercing propellers.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100625"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental validation on structure-borne underwater radiated noise transfer function analysis for marine structure","authors":"Joo-Yeob Lee ,&nbsp;Dae-Seung Cho ,&nbsp;Kookhyun Kim ,&nbsp;Sung-Ju Park","doi":"10.1016/j.ijnaoe.2024.100585","DOIUrl":"10.1016/j.ijnaoe.2024.100585","url":null,"abstract":"<div><p>In this paper, an experimental validation of a numerical procedure for estimating the structure-borne Underwater Radiated Noise (URN) Transfer Function (TF) of a marine structure based on the SEA theory has been performed. For the purpose, the structure-borne URN TF of a central point-excited one-side fluid-loaded four-edge stiffened plate in a reverberant water tank has been measured and compared with the SEA result. Additionally, the practical applicability of the procedure for a real ship structure has been demonstrated by comparing the URN analysis result based on the transfer function method and the measurement result for a Korean research vessel, ‘Cheong-Hae’. From the results, it is confirmed that the presented procedure can be used to estimate the structure-borne URN level emitted from the vibrating fluid-loaded side shells of a ship structure.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100585"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000049/pdfft?md5=c91106139b760af13bafcc4fa7976313&pid=1-s2.0-S2092678224000049-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139517115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics simulation model for the analysis of aircraft movement characteristics on an aircraft carrier deck","authors":"Byeong-Woo Yoo ,&nbsp;Kwang-Phil Park ,&nbsp;Jaewon Oh","doi":"10.1016/j.ijnaoe.2024.100591","DOIUrl":"https://doi.org/10.1016/j.ijnaoe.2024.100591","url":null,"abstract":"<div><p>Aircraft on an aircraft carrier deck are taxied or towed using a tractor. As these vehicles move within a limited area and are affected by the aircraft carrier motion, the possibility of aircraft movement in the entire space must be confirmed. The potential aircraft movements can be determined using simulations, wherein the movement characteristics of the aircraft must be analyzed by considering the movement of the carrier. Therefore, an aircraft dynamics simulation model considering the six-degrees-of-freedom movement of the platform is presented in this study to analyze the aircraft movement characteristics on the deck. The proposed model was verified using various reference data and models, and the simulation results of the multi-body dynamics analysis program DAFUL were employed to estimate the tire stiffness coefficient according to the slope. The proposed model facilitated the analysis of the movement characteristics of the aircraft by implementing driving simulations for various platform movements.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100591"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000104/pdfft?md5=c30ddb21c37e90f3d794b095539642bb&pid=1-s2.0-S2092678224000104-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hull form optimization of fully parameterized small ships using characteristic curves and deep neural networks","authors":"Jin-Hyeok Kim ,&nbsp;Myung-Il Roh ,&nbsp;In-Chang Yeo","doi":"10.1016/j.ijnaoe.2024.100596","DOIUrl":"10.1016/j.ijnaoe.2024.100596","url":null,"abstract":"<div><p>Designing a hull form typically involves beginning with a reference hull form based on ship owner requirements, editing the hull form to satisfy the requirements, and determining the most efficient hull form. Numerical analyses using Computational Fluid Dynamics (CFD) were employed to assess the performance of the hull form. However, these analyses require extensive computational resources, making it challenging to perform thorough analyses within the design timeframe. To address this issue, this paper proposes an approach that involves defining a range of hull forms with characteristic curves, predicting their performance using Deep Neural Networks (DNNs), and subsequently determining the optimal hull form based on these predictions. Initially, the hull form of a small ship was defined using four characteristic curves and parameterized using 29 variables. Fairness optimization was performed using these characteristic curves to define the hull form surface. By varying 29 parameters, 896 different hull forms were generated, with CFD analysis conducted for each variant. These data were then used to build a DNN model capable of predicting the performance based on hull form parameters. The accuracy of the DNN model was evaluated, resulting in a Mean Absolute Error (MAE) of 2.835%. Subsequently, the DNN model is combined with a genetic algorithm to identify the optimal set of parameters for the hull form, resulting in an optimal hull form. This optimization process revealed that the optimal hull form reduced the total hydrodynamic resistance by approximately 7% compared to the initial reference design. Consequently, this study demonstrates the effectiveness of the proposed method for deriving the optimal hull form for small ships.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100596"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000153/pdfft?md5=a64a5500a1535c3dfe132281d679a1c6&pid=1-s2.0-S2092678224000153-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141023308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of multi-functional integrated design system for ship block lifting process","authors":"Rui Li ,&nbsp;Zhang Quanyou ,&nbsp;Zhan Xiuguang ,&nbsp;Shan Julin ,&nbsp;Wan Hexin","doi":"10.1016/j.ijnaoe.2024.100593","DOIUrl":"10.1016/j.ijnaoe.2024.100593","url":null,"abstract":"<div><p>In order to solve the integration problem of lifting point layout, 3D dynamic simulation and safety assessment, a multi-functional integrated design system for ship lifting process is developed. Based on the discrete data extracted from AM model (The three-dimensional ship block created through AVEVA Marine), lifting process information and lifting equipment information, this paper develops an automatic design module with the optimization algorithm of lifting point layout as the core, and retains the interactive design module. To solve the problem of automatic finite element mesh generation, the proposed system uses the highly reliable AFT-Delaunay algorithm as the finite element mesh generation algorithm. In addition, the proposed system combines the control algorithm, unit calculation and constitutive calculation extension interface to build a finite element analysis framework. Taking the deck block of a crude oil tanker as an example, this paper compares the functions of commercial finite element software MSC.NASTRAN and the proposed system in the finite element calculation results, mesh generation and finite element visualization. The comparison results shows that the proposed system has reached a level comparable to MSC.NASTRAN in the safety evaluation of block lifting.</p></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100593"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2092678224000128/pdfft?md5=b7d88aaaef480f7000e825e1f4ac106b&pid=1-s2.0-S2092678224000128-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141040473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LDV measurements of boundary layer velocity profiles on flat plates with different surface roughnesses","authors":"Ji-Woo Hong ,&nbsp;Rafat I.A. Simanto ,&nbsp;Byoung-Kwon Ahn ,&nbsp;Se-Myun Oh ,&nbsp;Dong-Hyun Lee","doi":"10.1016/j.ijnaoe.2024.100619","DOIUrl":"10.1016/j.ijnaoe.2024.100619","url":null,"abstract":"<div><div>The dynamics acting upon thin flat plates submerged in a fluid are chiefly governed by the delicate boundary layer enveloping their surfaces. Through a series of experiments, we investigated the impact of surface roughness elements on the boundary layer adjacent to a flat plate across a range of Reynolds numbers. The experiments were performed in the Chungnam National University-Cavitation Tunnel (CNU-CT). Three flat plates, each characterized by distinct surface roughness heights denoted by <em>k</em>, were subjected to scrutiny. One boasted a pristine smoothness, while the others bore the deliberate roughness of sandpaper, each with its own unique texture. With precision instrumentation, including Laser Doppler Velocimetry (LDV), we meticulously documented the axial velocity profile and the RMS (Root Mean Square) velocity at strategic points along the flat plates. Through these measurements, we unveiled the boundary layer's thickness, <em>δ</em>, and momentum thickness, <em>θ</em>, elucidating their variations under differing free-stream velocities. As our exploration deepened, the relationship between the local Reynolds number, <em>Rn</em>_<em>x</em>, and the non-dimensional velocity profiles, <em>u</em>^<em>+</em> − <em>y</em>^<em>+</em>, became apparent. A systematic shift along the log-law line ensued, with both <em>u</em>^<em>+</em> and <em>y</em> ^<em>+</em> increasing in tandem with the rise in Rn_x. Yet, our inquiry did not conclude with observation alone. Employing empirical rigor, we quantified the drag forces acting upon flat plates of varying roughness heights, deriving them from the measured momentum thickness across a range of local Reynolds numbers, <em>Rn</em>_<em>x</em>.</div></div>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 ","pages":"Article 100619"},"PeriodicalIF":2.3,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical study on the high-speed ship hydrodynamics influenced by an interceptor with varied angle of attack","authors":"Arfis Maydino Firmansyah Putra, Hiroyoshi Suzuki","doi":"10.1016/j.ijnaoe.2023.100566","DOIUrl":"https://doi.org/10.1016/j.ijnaoe.2023.100566","url":null,"abstract":"<p>Efforts to improve the hydrodynamic performance of high-speed ships have been underway for a long time. There are different approaches, one of which is to take advantage of an interceptor. Conventionally, the interceptor blades are mounted vertically on the ship's bottom transom, oriented at a zero-degree angle of attack (<em>AoA</em>). This study comprehensively explores high-speed ships' hulls with and without interceptor configurations, encompassing both negative and positive <em>AoA</em> of the interceptor, conducted through experimental and numerical methods using a fully captive model. The interceptors are strategically positioned and configured. Each configuration was examined under varying <em>AoA</em> settings, with uniform interceptor depths and systematic trim angle adjustments. The Computational Fluid Dynamics (CFD) approach simulates the local flow dynamics around the hull, thoroughly analyzing resistance, pressure distribution, lift force, wave profile, and trim moment. The results indicate that interceptor placement near the keel with <em>AoA</em> adjustments significantly reduces hydrodynamic resistance, while <em>AoA</em> changes have limited impact in other positions. Lift force analysis shows interceptors improve lift compared to the bare hull, but this improvement is not linear across positions. Furthermore, it is observed that adjustments in <em>AoA</em> influence lift, with a negative <em>AoA</em> generally being considered favorable. In summary, carefully considering placement, <em>AoA</em>, and height-to-length ratio is necessary to maximize interceptor advantages.</p>","PeriodicalId":14160,"journal":{"name":"International Journal of Naval Architecture and Ocean Engineering","volume":"16 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139029531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}