Article
Chemistry, Analytical
Jinjun Li, Wu Ouyang, Qilin Liu, Zhuo Zhang, Yan Zhang
Summary: In this paper, an experiment on water-lubricated stern bearing (WSB) is conducted, and a bearing film-thickness identification model is established. The distributed lubrication characteristics of WSB under different speeds are systematically analyzed. The results show that the maximum identification error of the model is less than 7%, the lubrication state of the bearing changes dynamically with speed, and the area of each lubrication sub-region varies nonlinearly.
Article
Engineering, Mechanical
M. Wodtke, W. Litwin
Summary: The research focuses on thermal phenomena related to the operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests showed that the intensity of forced axial flow significantly affects the bush temperature. Numerical simulations revealed that restricted axial flow leads to backflow of water through the grooves, resulting in a higher backflow temperature than the supply temperature and an increase in bearing bush temperature.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Kun Yang, Tao Zhang
Summary: Deformation of the stern shaft caused by ship maneuvering can lead to lubrication failure and wear of the stern bearing. The deflection equation of the stern shaft under the action of interface force and propeller load was established using the displacement superposition method, and the fluid-solid coupling model of the stern bearing was established using the averaged Reynolds equation, the Greenwood-Tripp model, and the influence coefficient method. Experimental validation was conducted and the influence of shaft bending deformation on lubrication characteristics was discussed. The results indicate that shaft bending deformation affects lubrication characteristics along the axial and circumferential directions.
Article
Engineering, Mechanical
Qilin Liu, Wu Ouyang, Ruiqing Li, Yong Jin, Tao He
Summary: This paper aims to study the demand of underwater vehicles for water-lubricated stern bearings with low noise, low vibration, high load capacity, and long service life. A series of experiments was conducted to analyze the lubrication and vibration characteristics of three test bearings with different bushing materials and structures. The results indicate that under extreme working conditions, the modified polyurethane bearing shows the best comprehensive performance. Specific pressure and environment temperature significantly influence the bearing performance, while flow rate has limited effect. The research provides important references for the material and structure design and performance testing of water-lubricated stern bearings.
Article
Engineering, Mechanical
Tao He, Zhongliang Xie, Xin Tao, Kang Yang, Jian Jiao, Minli Huang, Wensheng Ma
Summary: This study proposes a water-lubricated stern bearing with self-adaptation capacity for load equalization and vibration reduction. By using elastic elements and damping alloy, the bearing can improve the service life and reduce vibration response.
Article
Engineering, Mechanical
Qilin Liu, Wu Ouyang, Qichao Cheng, Jinjun Li, Qizhi Cheng, Ruiqing Li
Summary: This paper investigates the lubrication and dynamic characteristics of water-lubricated stern bearing under service conditions. It proposes a test scheme to analyze the pressure distribution and spatial shaft position of the bearing. The experiment reveals the pressure bias and bidirectional shaft inclination phenomenon, and a dynamic model considering bidirectional shaft inclination and lining deformation is established. The study explores the influences of various factors on lubrication and dynamic characteristics and provides guidance for the design and optimization of such bearings.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Engineering, Mechanical
Dov Avishai, Groper Morel
Summary: This study examines the application of water-lubricated bearings in the propulsion systems of naval vessels, analyzing their lubrication status through experimentation and modeling. The goal is to reduce environmental pollution risks and improve the operational performance of ships.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Chemistry, Multidisciplinary
Yanfeng Han, Ting Tang, Guo Xiang, Hang Jia
Summary: This study investigates the impact of propeller shaft deflection on the fluid-solid-heat coupling performance of water lubricated rubber stern bearing, and develops a model to validate the findings. Results suggest that under heavy load conditions, the deflection of the stern shaft should be taken into account in the analysis of FSH performance of the JWR system.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Mechanical
Minghui Yang, Hong Lu, Xinbao Zhang, Yong Quan Zhang, Zhang Jie Li, Wei Zhang
Summary: This study investigates the mixed lubrication performances of stern bearing in a misaligned state considering the impacts of turbulence and bearing deformation. A mixed lubrication model is established, taking into account the interaction of bearing elastic deformation, asperity contact pressure, and film pressure. The effects of elastic deformation and turbulence on bearing behaviors are studied, and the correctness of the model is verified through comparison with published data.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2023)
Article
Engineering, Mechanical
Zhongliang Xie, Yun Zhang, Jinzhu Zhou, Weidong Zhu
Summary: This paper aims to reveal the micro interface lubrication regimes of water lubricated bearings through computational fluid dynamic analysis. The influences of operating conditions and dimensionless structural parameters on fluid features are explored, and experimental data verifies the correctness of the lubrication model. The research results lay a solid foundation for further optimal design of such bearings.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Engineering, Mechanical
Guangwu Zhou, Renpan Li, Daxin Liao, Wanyou Yang, Ping Zhong
Summary: In order to meet the urgent requirements of shaftless rim-driven thrusters for low and medium speed, high load capacity, and wear-resistant water-lubricated bearings, this paper conducted research on the lubrication structure design of water-lubricated spiral groove rubber thrust bearings (SGRTBs). A mixed lubrication analysis technique was proposed, considering the effect of surface roughness, and the optimization design of the spiral groove structure parameters was achieved, addressing the mixed lubrication issue of typical spiral surface contact.
TRIBOLOGY INTERNATIONAL
(2023)
Review
Engineering, Mechanical
Zhongliang Xie, Jian Jiao, Kang Yang, Hao Zhang
Summary: This paper provides a detailed summary of water-lubricated bearings in five typical aspects: lubrication regime, fluid-solid interaction (FSI), thermal effect, tribological behaviors, and vibration-noise performances. It extracts and acquires the influencing factors, judgement criteria, and lubrication mechanism of the lubrication regime. The methodology and parameters influencing temperature rise are summarized. The generation mechanism of tribological behaviors and vibration & noise is obtained. The paper systematically combs and summarizes the theories and methods of water-lubricated bearings, pointing out the existing problems and urgent technologies that need to be solved. The findings can serve as a distinct theoretical and methodological reference for further investigation on water-lubricated bearings.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Wu Ouyang, Qilong Yan, Junxin Kuang, Yong Jin, Weicai Peng
Summary: By introducing the squeeze film damper technology, the design of ship water-lubricated stern bearing successfully balances high load-carrying capacity and low natural frequency. Experimental results indicate that WDSB shows significant vibration reduction effect compared to CWSB.
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2021)
Article
Engineering, Mechanical
Zijun Leng, Fangrui Lv, Jianbo Zhang, Chunxiao Jiao, Gengyuan Gao, Na Ta, Zhushi Rao
Summary: The dynamic coefficients of water-lubricated marine stern tube bearings are enhanced by roughness, but weakened when considering bush deformation. Additionally, rougher bearings have significantly smaller dynamic coefficients than smoother bearings as the misalignment angle increases.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Zhongliang Xie, Weidong Zhu
Summary: The paper investigates the micro asperity contact load ratios and lubrication states of water-lubricated bearings. New coupled models are proposed to consider the micro-scale effects of asperity contact. The study establishes the relevance of load ratio with transition of lubrication regimes under various structural parameters and operating conditions, revealing the mechanism of regimes transition at the micro level. Experimental measurements verify the correctness of the revised model.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Civil
Bin Wang, Wu Ouyang, Shengtong Wang, Chenxing Sheng, Jinhua Xiao, Zhe Li
Summary: In this study, a novel Magnetic Liquid-double-suspension Elastic-supported Thrust Bearing (MLETB) is designed for the heavy load and low viscosity operation conditions of the marine rim-driven thruster (RDT). The MLETB combines the structural features of the Rubber-supported Water-lubricated Thrust Bearing (RWTB) and Permanent Magnet Bearing (PMB). The experimental results show that the MLETB has better load capacity and dynamic performance, but its stiffness and damping are seriously affected by the specific rubber structure.
INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
(2023)
Review
Electrochemistry
Jinhua Xiao, Chengran Jiang, Bo Wang
Summary: With the increasing demand for retired EVs, the recycling of EV batteries is attracting more attention towards its disassembly and echelon utilization to ensure efficient resource utilization and environmental protection. This paper discusses various possible methods for echelon utilization, including hierarchical analysis based on battery evaluation index, and reviews the retired EV battery disassembly through human-robot collaboration. Finding a suitable recycling mode and disassembly process is essential to improve efficiency and reduce costs in EV recycling. This study explores the future potential of echelon utilization and disassembly in retired EV battery recycling, facing uncertainties in disassembly and echelon utilization.
Article
Computer Science, Interdisciplinary Applications
Yanfang Yang, Miao Yang, Nabil Anwer, Benoit Eynard, Liang Shu, Jinhua Xiao
Summary: In order to ensure higher efficiency and better performance in the flexible production workshop, the optimum reschedules need to be considered based on actual production requirements. Traditional rescheduling methods might be time-consuming for order arrivals. To solve this problem, a digital twin-assisted prediction rescheduling approach is proposed to support efficient rescheduling in flexible production workshops. By considering the differences between traditional and predictive rescheduling, the proposed method can acquire optimal reschedules before order arrivals, reducing reactive time and improving real-time performance of production workshops.
COMPUTERS & INDUSTRIAL ENGINEERING
(2023)
Article
Engineering, Manufacturing
Jinhua Xiao, Jiaxu Gao, Nabil Anwer, Benoit Eynard
Summary: By combining human-robot collaboration and Multi-Agent Reinforcement Learning, an intelligent battery recycling system can be established to address the challenges in retired EV battery recycling efficiency.
JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME
(2023)
Article
Engineering, Mechanical
Changxiong Ning, Wu Ouyang, Fei Hu, Xinping Yan, Dongling Xu
Summary: This paper proposes a wear monitoring method based on an improved ultrasonic reflection coefficient amplitude spectrum to overcome the challenges caused by the viscoelasticity, heterogeneity, and acoustic attenuation of polymer materials. The method utilizes an ultrasonic transfer function and a differential evolutionary algorithm to accurately determine the thickness, sound velocity, density, and attenuation coefficients of polymer bearings. Experimental results demonstrate that the method achieves a thickness identification error of approximately 0.5% for different probe contact pressure, roughness, and tilt angle conditions, and a reconfiguration thickness identification error of less than 1% for all water film overlap situations.
Article
Engineering, Mechanical
Qilin Liu, Wu Ouyang, Ruiqing Li, Yong Jin, Tao He
Summary: This paper aims to study the demand of underwater vehicles for water-lubricated stern bearings with low noise, low vibration, high load capacity, and long service life. A series of experiments was conducted to analyze the lubrication and vibration characteristics of three test bearings with different bushing materials and structures. The results indicate that under extreme working conditions, the modified polyurethane bearing shows the best comprehensive performance. Specific pressure and environment temperature significantly influence the bearing performance, while flow rate has limited effect. The research provides important references for the material and structure design and performance testing of water-lubricated stern bearings.
Review
Engineering, Mechanical
Zhuo Zhang, Wu Ouyang, Xingxin Liang, Xinping Yan, Chengqin Yuan, Xincong Zhou, Zhiwei Guo, Conglin Dong, Zhenglin Liu, Yong Jin, Jinhua Xiao
Summary: With the development of green tribology in the shipping industry, water lubrication is gradually replacing oil lubrication in stern bearings and thrust bearings. However, water-lubricated bearings face challenges such as friction, wear, vibration, and noise. This review focuses on the performance and failure prevention mechanism of marine water-lubricated bearings, discussing lubrication principle, test technology, friction and wear mechanism, and friction noise generation mechanism. The methods of performance enhancement through structure optimization and material modification are discussed, and potential problems and future perspectives of water-lubricated bearings are provided in detail.
Article
Engineering, Marine
Yong Jin, Ruiqing Li, Wu Ouyang, Zhenglin Liu, Qilin Liu, Qipeng Xiong, Jianhui Zhou
Summary: Under low speed and heavy load operating conditions, the marine water-lubricated bearing (WLB) experiences abnormal friction-induced vibrations and noise in underwater vehicles due to mixed lubrication state. An empirical mode decomposition (EMD) based method was proposed to identify the friction-induced vibration characteristics of WLB and experiments were conducted. The study revealed that specific pressure and lubricant temperature had significant effects on friction-induced vibrations, while cooling water flow had little effect. Analyzing the characteristics of IMF energy, time-domain standard deviation, bias angle, and center of gravity frequency could visualize the trend and critical points of friction-induced vibrations.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Chemistry, Physical
Yong Hu, Dianyu Tang, Lei Yang, Yudong Lin, Chao Zhu, Jinhua Xiao, Chunze Yan, Yusheng Shi
Summary: In this study, a 3D transient multi-physics model based on computational fluid dynamics (CFD) is proposed to analyze the temperature and stress distribution during the Laser powder bed fusion (L-PBF) process of NiTi shape memory alloy. The influence of process parameters on the molten pool shape is analyzed and a nonlinear regression equation is proposed for predicting the molten pool size. Experimental results verify the reliability of the established simulation method with a prediction error of 3% - 8%.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Proceedings Paper
Computer Science, Artificial Intelligence
Guoxian Wang, Jiaxu Gao, Jinhua Xiao
Summary: This paper proposes an optimal strategy for the disassembly process in electric vehicle batteries based on human-machine collaboration re-manufacturing. It combines artificial intelligence algorithms to identify and position operational targets, optimize the sequence of man-machine operation tasks, and improve the efficiency and safety of the disassembly process. Finally, the research prospects for the implementation of the overall strategy and future development direction are proposed.
2023 9TH INTERNATIONAL CONFERENCE ON MECHATRONICS AND ROBOTICS ENGINEERING, ICMRE
(2023)
Proceedings Paper
Computer Science, Artificial Intelligence
Guoxian Wang, Hongjing Wu, Jinhua Xiao
Summary: In order to reduce the environmental impact of new energy vehicle batteries, the recycling and disassembly of electric vehicle batteries has received widespread attention. A genetic algorithm-based evaluation method for the selection of tools in the recycling and disassembly of electric vehicle batteries is proposed, aiming to address the issues of manual operation and dependence on appropriate tools during the disassembly process. An optimization model for disassembly tools is established, and further research and prospects are conducted on the proposed model.
2023 9TH INTERNATIONAL CONFERENCE ON MECHATRONICS AND ROBOTICS ENGINEERING, ICMRE
(2023)
Article
Engineering, Marine
Alba Ricondo, Laura Cagigal, Beatriz Perez-Diaz, Fernando J. Mendez
Summary: This research presents a site-specific metamodel based on the SWASH numerical model simulations, which can predict coastal hydrodynamic variables in a fast and efficient manner. The metamodel uses downscaled and dimensionality reduced synthetic database to accurately reproduce wave setup, wave heights associated with different frequency bands, and wave runup. This method has great potential in coastal risk assessments, early warning systems, and climate change projections.
Article
Engineering, Marine
Xiao Yu, Wangjun Ren, Bukui Zhou, Li Chen, Xiangyun Xu, Genmao Ren
Summary: This study investigated and compared the compression responses and energy absorption capacities of coral sand and silica sand at a strain rate of approximately 1000 s-1. The results showed that coral sand had significantly higher energy absorption capacity than silica sand due to its higher compressibility. The study findings suggest that using poorly graded coral sand can improve its energy absorption capacity.
Article
Engineering, Marine
Jingxi Zhang, Junmin Mou, Linying Chen, Pengfei Chen, Mengxia Li
Summary: This paper proposes a cooperative control scheme for ship formation tracking based on Model Predictive Control. A predictive observer is designed to estimate the current motion states of the leader ship using delayed motion information. Comparative simulations demonstrate the effectiveness and robustness of the proposed controller.
Article
Engineering, Marine
Yu Yao, Danni Zhong, Qijia Shi, Ji Wu, Jiangxia Li
Summary: This study proposes a 2DH numerical model based on Boussinesq equations to investigate the impact of dredging reef-flat sand on wave characteristics and wave-driven current. The model is verified through wave flume experiments and wave basin experiments, and the influences of incident wave conditions and pit morphological features on wave characteristics are examined.
Article
Engineering, Marine
Jayanta Shounda, Krishnendu Barman, Koustuv Debnath
Summary: This study investigates the double-average turbulence characteristics of combined wave-current flow over a rough bed with different spacing arrangements. The results show that a spacing ratio of p/r=4 offers the highest resistance to the flow, and the double-average Reynolds stress decreases throughout the flow depth. The advection of momentum-flux of normal stress shows an increase at the outer layer and a decrease near the bed region after wave imposition. Maximum turbulence kinetic energy production and diffusion occur at different layers. The turbulence structure is strongly anisotropic at the bottom region and near the outer layer, with a decrease in anisotropy observed with an increase in roughness spacing.
Article
Engineering, Marine
Meng Zhang, Lianghui Sun, Yaoguo Xie
Summary: The research proposes a method for online identification of wave bending and torsional moment in hull structures. For structures without large openings, the method optimizes sensor positions and establishes a mathematical model to improve accuracy. For structures with large openings, a joint dual-section monitoring method is proposed to simultaneously identify bending and torsional moments in multiple key cross sections.
Article
Engineering, Marine
Longming Chen, Shutao Li, Yeqing Chen, Dong Guo, Wanli Wei, Qiushi Yan
Summary: This study investigated the dynamic response characteristics and damage modes of pile wharves subjected to underwater explosions. The results showed that the main damaged components of the pile wharf were the piles, and inclined piles had a higher probability of moderate or more significant damage compared to vertical piles. The study also suggested that replacing inclined piles with alternative optimized structures benefits the blast resistance of pile wharves.
Article
Engineering, Marine
I. -C Kim, G. Ducrozet, V. Leroy, F. Bonnefoy, Y. Perignon, S. Bourguignon
Summary: Previous research focused on the accuracy and efficiency of short-term wave fields in specific prediction zones, while we developed algorithms for continuous wave prediction based on the practical prediction zone and discussed important time factors and strategies to reduce computational costs.
Article
Engineering, Marine
Hang Xie, Xianglin Dai, Fang Liu, Xinyu Liu
Summary: This study investigates the load characteristics of a three-dimensional stern model with pitch angle through a drop test, and reveals complex characteristics of pressure distribution near the stern shaft. The study also shows that the vibration characteristics of the load are influenced by the drop height and pitch angle, with the drop height having a greater effect on the high-frequency components.
Article
Engineering, Marine
Hangyuan Zhang, Wanli Yang, Dewen Liu, Xiaokun Geng, Wangyu Dai, Yuzhi Zhang
Summary: The deep-water bridge is more vulnerable to earthquake damage than the bridge standing in air. The larger blocking ratio has a significant impact on the added mass coefficient, which requires further comprehensive study. The generation mechanism of block effect is analyzed using numerical simulation software ANSYS Fluent. The results show that the recirculation zone with focus reduces the pressure on the back surface of the cylinder, resulting in the peak value of in-line force not occurring synchronously with the peak value of acceleration. The change in position and intensity of the recirculation zone with focus, as well as the change in water flow around the cylinder surface, are identified as the generation mechanism of the block effect, which has a 10% influence on the hydrodynamic force. The changing rule of the added mass coefficient with blocking ratio is discussed in detail, and a modification approach to the current added mass coefficient calculation method is suggested. Physical experiments are conducted to validate the modification approach, and the results show that it is accurate and can be used in further study and real practice.
Article
Engineering, Marine
Golnesa Karimi-Zindashti, Ozgur Kurc
Summary: This study examines the performance of an in-house code utilizing a deterministic vortex method on the rotation of circular and square cylinders. The results show that rotational motion reduces drag forces, suppresses fluctuating forces, and increases lift forces. The code accurately predicts vortex shedding suppression and identifies the emergence of near-field wakes in the flow over rotating square cylinders.
Article
Engineering, Marine
George Dafermos, George Zaraphonitis
Summary: The survivability of damaged ships is of great importance and the regulatory framework is constantly updated. The introduction of the probabilistic damage stability framework has rationalized the assessment procedure. Flooding simulation tools can be used to investigate the dynamic response of damaged ships.
Article
Engineering, Marine
Xuyue Chen, Xu Du, Chengkai Weng, Jin Yang, Deli Gao, Dongyu Su, Gan Wang
Summary: This paper proposes a real-time drilling parameters optimization method for offshore large-scale cluster extended reach drilling based on intelligent optimization algorithm and machine learning. By establishing a ROP model with long short-term memory neurons, and combining genetic algorithm, differential evolution algorithm, and particle swarm algorithm, the method achieves real-time optimization of drilling parameters and significantly improves the ROP.
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, Marine
G. Clarindo, C. Guedes Soares
Summary: Environmental contours are constructed using the Inverse-First Order Reliability Method based on return periods. The paper proposes the use of the Burr distribution to model the marginal distribution of long-term significant wave heights. The newly implemented scheme results in different environmental contours compared to the reference approach.