Article
Engineering, Marine
A. C. Pillai, T. J. Gordelier, P. R. Thies, D. Cuthill, L. Johanning
Summary: This paper presents the results of coupled dynamic simulations evaluating the influence of synthetic and novel mooring tethers on anchor loads and platform dynamics in shallow waters. The study finds that replacing chain with polyester ropes or novel mooring tethers effectively reduces peak anchor loads but increases platform excursions. However, compliant novel moorings can reduce excursions while maintaining lower load profiles, and deploying taut moored systems can further minimize excursions.
Article
Engineering, Marine
Zhengru Ren, Hongyu Zhou, Binbin Li, Zhenzhong Hu, Menghong Yu, Wei Shi
Summary: This paper introduces a novel localization scheme for moored floating structures, which utilizes tension measurements to provide real-time position references and estimate unknown anchor positions. The proposed method enhances safety by extracting redundant position information from tension measurements. A line-of-sight model and various considerations are presented to provide a realistic and robust tension-based localization scheme.
Article
Environmental Sciences
Shaowei Zhang, Chuan Tian, Fenghua Zhou
Summary: For long-term mooring buoy observatories in the deep sea far from the coasts, the hybrid system called MBOSBC (Mooring Buoys Observation System with Benthic Electro-optical-mechanical Cable) is designed. The system uses an Electro Optical Mechanical (EOM) cable to connect the sea surface buoy and benthic observation node for information and power transmission. The EOM cable plays a crucial role in mooring and ensuring the long-term and effective operation of the system.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Mechanics
Huidong Zhang, Tong Wang, Cong Xu, Hongda Shi, Carlos Guedes Soares
Summary: A new wave energy converter is proposed, consisting of three split heave point absorbers and a taut-moored floating turbine, which is suitable for waves in the China Sea with short periods and small amplitudes. Physical model tests reveal that the new device significantly improves wave energy capture efficiency for short-period waves in low sea states. The submerged platform contributes to this improvement through out-of-phase heave motion and the induced shallow water effect, particularly with a high damping force in the power takeoff system. However, the high-frequency oscillation caused by the coincident wave direction and mooring lines needs further optimization of the taut mooring system.
Article
Engineering, Marine
Sung-Jae Kim, Chungkuk Jin, MooHyun Kim
Summary: This study investigates the dynamic behavior of a moored submerged floating tunnel (SFT) under tsunami-like waves through numerical simulations and sensitivity tests. The results show that design parameters significantly affect the dynamics of the SFT system and mooring tensions, with shorter-duration and higher-elevation tsunamis having a greater impact.
Article
Engineering, Ocean
Ben Howey, Keri M. Collins, Martyn Hann, Gregorio Iglesias, Rui P. F. Gomes, Joao C. C. Henriques, Luis M. C. Gato, Deborah Greaves
Summary: This study investigates different configurations of a five-device array of spar-buoy oscillating-water-column wave energy converters in a wave basin and compares the performance of arrays with different levels of connectivity. The results show that interconnected array configurations lead to a significant increase in energy extraction efficiency.
APPLIED OCEAN RESEARCH
(2021)
Article
Engineering, Chemical
Sung Youn Boo, Steffen Allan Shelley
Summary: This paper presents the design and analysis of a mooring buoy and its mooring systems for mooring a floating platform with Wave Energy Converters. The buoy allows the platform to weathervane freely, ensuring consistent power generation. Fully coupled time-domain analyses are conducted under various sea states to evaluate buoy motions, mooring tensions and design parameters. Strength and fatigue designs of the mooring systems comply with industry standards. Global and local structural designs of the mooring buoy confirm compliance.
Article
Engineering, Marine
Alana Pols, Eric Gubesch, Nagi Abdussamie, Irene Penesis, Christopher Chin
Summary: This study focuses on modeling a floating oscillating water column (FOWC) wave energy converter using the ANSYS AQWA numerical code based on potential flow theory. The lack of viscosity in the numerical modeling led to overpredicted motions near resonant frequencies, but adding an external linear damping coefficient was shown to mitigate these discrepancies. The incident wave angle had limited influence on the magnitudes of heave, pitch, and surge motions, while the mooring restoring force was primarily controlled by the forward mooring lines under the tested conditions.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Marine
S. C. Mohapatra, Guedes Soares
Summary: An analytical model of moored floating flexible net cage systems was developed to study dynamics and wave loads. Results were compared with finite element analysis and experimental data, and various factors were analyzed for their effects on system performance. This study is important for the design of multiple floating fish cage systems in offshore aquaculture.
Article
Engineering, Marine
Vincenzo Piscopo, Antonio Scamardella, Giovanni Battista Rossi, Francesco Crenna, Marta Berardengo
Summary: The fatigue assessment of mooring lines is crucial for the design and economic impact of floating offshore wind turbines. This study focuses on the nonlinear time-domain hydrodynamic model of floating offshore wind turbines moored by chain cables and proposes a combined-spectrum approach for fatigue damage assessment. The study estimates fatigue parameters using both time-domain analysis and advanced spectral analysis methods. The results demonstrate that advanced spectral analysis methods can improve the reliability of fatigue life assessment for mooring lines.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Environmental Sciences
Changqing Jiang, Ould el Moctar, Guiyong Zhang
Summary: Within the Space@Sea project, a multi-use floating concept was proposed to enlarge a floating platform using smaller structures. An analysis was conducted to identify the seakeeping criteria and their impact on functionality. The response of the floating concept was calculated in head waves considering nonlinearities and interactions. Assessments were carried out for safety and comfort criteria, with a focus on rotational motions and vertical acceleration as the determining factors.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Engineering, Marine
Junrong Wang, Chunlei He, Dezhi Wang, Kuang He, Zhenyang He, Min Zhang, Kun Xu
Summary: This study investigates the mesh-convergence laws for a panel model used to calculate second-order potentials. The effect of the relative-wave-height component on low-frequency wave forces is sensitive to the mesh near the waterline. The difference-frequency band of the quadratic transfer function matrix is also studied.
Article
Engineering, Marine
I. B. S. Bispo, S. C. Mohapatra, C. Guedes Soares
Summary: This paper presents a numerical model for wave interaction with a moored articulated very large floating structure. The effects of different design parameters on wave elevation and wave forces are analyzed, and it is found that increasing wavelength leads to higher reflection coefficient and lower transmission coefficient. The stiffness of the hinges has little effect on these coefficients, but the rotational stiffness greatly affects the vertical displacement of the structure and the tensions on the mooring lines.
Article
Engineering, Ocean
William M. West, Andrew J. Goupee, Chris K. Allen, Anthony M. Viselli
Summary: As the floating offshore wind industry matures, researchers are focusing on the next-generation materials and processes to overcome the challenges of traditional systems. Synthetic ropes are one such technology that has gained prominence. However, designing moorings with synthetic ropes is complex due to the physics of the materials. In this article, a modified mooring modeling module was used to successfully simulate test data under representative design load cases.
JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Marine
Hongjie Wen, Gancheng Zhu, Bing Ren, Xuefeng Chang, Jinquan Wu, Yongxue Wang
Summary: This paper proposes a multi-buoy-assisted mooring system to improve the safety performance of moored ships. Experimental tests on a bulk cargo ship show that the developed system can effectively prevent cable breakage and fender damage, with limited impact on the load and unload operations of the ship.
