Article
Engineering, Marine
Xinwei Chen, Yang Yu, Lei Wang
Summary: This study introduces a framework to evaluate and compare scour prediction models, focusing on design robustness. By applying this framework, the study recommends the most favorable scour prediction model and optimal design for monopiles in OWTs.
Article
Engineering, Marine
Ling Zhu, Zhihui Zhou, Preben Terndrup Pedersen
Summary: Ship grounding experiments are crucial for validating numerical analysis and theoretical formulations. In this study, small-scale ship model grounding tests on a sharp rock were conducted in a water tank to observe and record different damage modes, ship bottom plate damage extents, and ship motion. The test results were used to analyze the energy dissipation process and the influence of initial conditions on ship response and damage.
Article
Engineering, Marine
Yuelin Song, Qin Dong, Jiping Zhang, Guoqiang Li, Dongfang Xu, Ping Yang
Summary: The objective of this research is to study the characteristics of low-cycle fatigue crack propagation from the perspective of accumulative plastic damage and propose a reliable prediction model for crack growth in EH-36 steel under high stress levels. Experimental findings demonstrate that increasing the mean stress and stress amplitude accelerates the progression of fatigue damage.
Article
Engineering, Marine
Lihua Xu, Jiasong Wang, Michael S. Triantafyllou, Dixia Fan
Summary: This paper presents a data assimilation method based on the POD-DeepONet structure to fuse two types of fidelity data from vortex-induced vibration (VIV) problems. The POD-DeepONet structure provides better accuracy and more stable predictions for amplitude response, successfully capturing the changing trend with the oncoming flow speed. The exponentially fitted MSE formula allows for quick determination of the required case number under the expected error.
Article
Engineering, Marine
Ilias Gavriilidis, Aris G. Stamou, Christos Palagas, Efthimios Dourdounis, Nikos Voudouris, Athanasios Tazedakis, Spyros A. Karamanos
Summary: This study investigated the collapse resistance of thick-walled steel pipes fabricated with the JCO-E process for deep offshore applications. It conducted a comprehensive analysis using experimental, numerical, and analytical approaches to examine the effects of heat treatment on the collapse behavior of two JCO-E pipes. The results were compared with the predictions of the DNV-ST-F101 standard, and the fabrication factor afa was discussed. The study also explored the impact of yield strength recovery due to heat treatment on the collapse of pipes with different D/t ratios.
Article
Engineering, Marine
Baoshun Zhou, Zhixun Yang, Mostafa Amini-Afshar, Yanlin Shao, Harry B. Bingham
Summary: In the hydroelastic analysis of large floating structures, accurate prediction of response relies on the structural stiffness. However, obtaining exact structural stiffness is challenging due to the complexity of modern ship structures. This study proposes an efficient analysis technique that combines finite element and finite difference methods to calculate structural stiffness and solve hydrodynamic problems.
Article
Engineering, Marine
Chunhao Jiang, Lin Lin, Nian-Zhong Chen
Summary: A novel type of side structure for enhancing the crashworthiness of double-hull vessels is proposed based on auxetic materials. Numerical simulation demonstrates the resistance to collision of three different unit cells. A comparative study shows that the proposed side structures have superior energy absorption and collision resistance compared to traditional side structures.
Article
Engineering, Marine
Yu Lei, Wei Li, Xiang Yuan Zheng, Huadong Zheng, Shan Gao, Shengxiao Zhao
Summary: This paper compares the numerical results of a floating offshore wind turbine integrated with a steel fish farming cage (FOWT-SFFC) against experimental data. The study shows that the simulated responses are in good agreement with the experimental data and reveals the important influence of second-order wave forces on the simulation results.
Article
Engineering, Marine
Yujia Wei, Shuangrui Yu, Peng Jin, Luofeng Huang, Khaled Elsherbiny, Tahsin Tezdogan
Summary: This paper presents a time-domain hydro-elastic-moored model to investigate the coupled effects between structural hydroelasticity and loose-type mooring systems on a deformable VLFS. The results can be used to design a VLFS with mooring in medium-deep sea and help with the conventional mooring design for a less-stiffness VLFS due to hydroelastic response.
Article
Engineering, Marine
Chenyu Luan, Torgeir Moan, Knut Andreas Kvale, Zhengshun Cheng
Summary: This paper deals with the study of the shear lag effect on the bending moment distribution in pontoon-type floating bridges. Comparative and parametric studies are carried out using beam and linear shell models to analyze the influence of shear lag on the bending stiffness and eigenmode shapes of the bridges. The study shows that elementary beam models may inaccurately predict the bending moments in bridges with large width and short span lengths, and a practical method is proposed to determine when caution is needed in using these models. The paper also highlights the complex boundary conditions near the bank abutment and the significant influence of shear lag on the bending moments in this region.
Article
Engineering, Marine
Sung-Jae Kim, Chungkuk Jin, MooHyun Kim
Summary: This study evaluates the effects of tsunami waves on the global performance of a spread-moored Floating Storage Unit (FSU) through tsunami-floater-mooring coupled dynamics simulations. The results show that larger tsunami heights and relatively short durations result in significantly increased motions and mooring tensions of the FSU.
Article
Engineering, Marine
Zhiping Zheng, Yanlin Shao, Jikang Chen
Summary: This study investigates the effect of horizontal low-frequency (LF) displacements and velocities on the responses of floating structures in irregular waves, focusing on a deep-draft spar buoy. The study finds that incorporating LF displacements and velocities in the seakeeping analysis is essential for reducing surge and pitch responses. The standard deviations of LF surge and pitch motions scale with significant wave height, highlighting viscous damping as the dominating damping mechanism.
Article
Engineering, Marine
Birendra Chaudhary, Hewenxuan Li, Akongnwi Nfor Ngwa, Helio Matos
Summary: This study investigates the long-term performance and effectiveness of coating systems for 3D-printed pressure vessels subjected to accelerated aging. The results show that the application of polyurethane coating systems significantly slows the degradation process, reducing critical operational depth and increasing pressure differential. This research contributes important insights into enhancing the longevity and performance of 3D-printed pressure vessels through coating systems.
Article
Engineering, Marine
Yang-Bin Chen, Yong Fu, Min-Hao Zhang, Zhen-Yu Yin, Jian Cheng
Summary: This paper systematically investigates the bending moment capacity and failure mechanism of caisson foundations under monotonic and cyclic loading in clay using finite element analyses. The influence of caisson-soil contact mode and soil strength reduction during installation is also explored. The study provides insights into the behavior of caisson foundations and can contribute to their design.
Article
Engineering, Marine
Zhenmian Li, Yang Yu, Xin Liu, Xiaowei Liu, Xiangyang Wang, Leige Xu, Jianxing Yu
Summary: This study evaluates the local collapses and propagating buckles of offshore pipelines under external overpressure, reverse fault displacements, and collapse failures. Different designs of integral arrestors are tested in a numerical model, and the effects of fault dip angles are investigated. The results show that integral arrestors are effective in preventing propagating buckles.
Article
Engineering, Marine
Hao Ding, Bo Huang, Liang Cheng, Ke Li, Qingyang Ren
Summary: This study investigates the dynamic response and cable forces of a submerged floating tunnel (SFT) under wave and wave-current interactions. Experimental results show that wave height, current velocity, and ratio of wavelength to structure size are important factors affecting the dynamic response of SFT and cable forces. The multi-anchor cable arrangement used in the experiments distributes cable forces more effectively and reduces potential safety hazards caused by cable breakage.
Article
Engineering, Marine
Hongdan Liu, Zhicheng Jia, Bing Li, Yan Liu, Zhigang Qi
Summary: This paper explores the monitoring and detection mechanism of vessel abnormal behavior based on Graph Attention Prediction and Reconstruction Network. It proposes a sliding window mechanism to generate fixed data input, effectively capturing the inter-dependencies among vessel behavior characteristics. The proposed mechanism dynamically adjusts the anomaly detection threshold based on variations in the marine environment, leading to an enhancement in the accuracy of detecting abnormal behavior in vessels.
Article
Engineering, Marine
Heath Palmer, Ming Zhao, Helen Wu, Pan Hu, Mohammad Rashed Mia, Chengwang Lei
Summary: This study investigates the improvement of hydrodynamic efficiency in dual chamber oscillating water columns (OWC) through numerical simulations. The results show that the dual chamber dual turbine configuration achieves higher efficiency compared to single chamber single turbine and dual chamber shared turbine configurations, operating over a broader range of wavelengths.
Article
Engineering, Marine
Ashok Kumar Pradhan, Ashok Kumar Barik, Manmatha Kumar Roul, Prafulla Kumar Swain
Summary: This study examines the tandem hydrofoil with two new flapping trajectories, elliptical and fishtail, to enhance induced thrust. Computational methods are used to analyze the hydrodynamic efficiency and the effects of Strouhal number and inter-foil spacing on the tandem hydrofoil.
Article
Engineering, Marine
Domenico Ferraro, Francesco Aristodemo, Agostino Lauria, Emilio Lazzaro, Davide Pasquali, Marcello Di Risio
Summary: This paper addresses the influence of waves on propeller jets in unconfined conditions, leading to alterations in scour and deposition patterns. Experimental tests and numerical simulations were conducted to investigate the effects of wave-induced velocity on the propeller jets hydrodynamics, providing insights into the complex bathymetry configuration induced by the propeller jet and waves.
