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
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
Mechanics
Fangrui Lv, Xinjie Zhang, Cuicui Ji, Zhushi Rao
Summary: Due to their low load-carrying capacity, low-viscosity lubricated bearings can operate easily in a mixed-lubrication regime. This study proposes a simulation approach that considers the effects of local turbulence on the transient characteristics of mixed-lubrication bearings and validates the model through experiments.
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
Pan Wang, He Liang, Liang Jiang, Linmao Qian
Summary: Surface roughness has a significant impact on friction and wear, especially at the nanoscale. This study investigates the effect of nanoscale surface roughness on sliding friction and wear. The research reveals that reducing surface roughness decreases friction and wear in mixed lubrication, but excessively low roughness can lead to friction failure. The findings enhance our understanding of the role of surface roughness in tribology.
Article
Engineering, Mechanical
Zeliang Xiao, Xi Shi, Xi Wang, Xiaolong Ma, Yunting Han
Summary: The lubrication performance of herringbone gear is degraded by increased pressure and temperature rise due to larger tooth surface roughness and rotational speed. In the start-stop phase, the tooth wear depth of herringbone gear may be greatly reduced with a larger start-stop acceleration. Overall, the research indicates that large tooth surface roughness is more likely to cause thermo-mechanical and wear failures in herringbone gear drive compared to high load.
Article
Metallurgy & Metallurgical Engineering
Xiu-jiang Shi, Xi-qun Lu, Tao He, Wen Sun, Qing-shun Tong, Xuan Ma, Bin Zhao, Dong Zhu
Summary: This paper investigates the friction and flash temperature in marine transmission gears, using a numerical solution procedure and mixed lubrication simulation to analyze the influence of different surface roughness. It is observed that heavy load and low rotational velocity conditions lead to significantly increased friction and temperature, while optimizing gear design parameters can greatly improve performance.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2021)
Article
Engineering, Marine
Junchao Zhu, Guangcheng Wei, Zilong Peng, Zhaowang Xia, Liangyan Zheng, Hanhua Zhu
Summary: This paper investigates the impact of underwater explosion shock on the lubrication performance of ship stern bearings. A coupling model of shaft longitudinal vibration and bearing lubrication is established, and the influencing factors are analyzed.
INTERNATIONAL JOURNAL OF NAVAL ARCHITECTURE AND OCEAN ENGINEERING
(2022)
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
Omar Morad, Vesa Saikko, Raine Viitala
Summary: This paper investigates the performance of lip seals used in marine thrusters, which have received less attention compared to lip seals in other fields. The main differences between marine and non-marine lip seals are the material compound, oil pressure, and diameters. A full-scale test device is built to study the effects of marine-specific parameters using a parameter sweep of oil temperature, oil pressure, and rotational speed. Air bearings are used for accurate measurement of frictional torque. The subsurface temperature at the contact is measured using a wireless temperature probe inside the rotating shaft liner, which will be used in future work to estimate the average contact temperature.
Article
Engineering, Mechanical
Juan Guo, Guo Xiang, Jiaxu Wang, Yankui Song, Jianlin Gai, Haiming Dai
Summary: This paper introduces a method of one-side profile modification for reducing the edge wear caused by journal defection in misaligned journal bearings. The effectiveness of the modification is confirmed through numerical calculations. The results indicate that the reasonable design of one-sided profile modification can increase the minimum film thickness at the edge of the bearing and reduce rough contact, thus improving the anti-wear performance of the misaligned journal bearing.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2022)
Article
Engineering, Mechanical
Wen Sun, Xiujiang Shi, Deliang Hua, Renze Li, Xuan Ma, Bin Zhao, Xiqun Lu
Summary: Marine transmission gears often face severe working conditions, leading to stress concentration and potential wear issues. Optimizing gear parameters and surface treatments can improve the stress state and contact effect of gears. The combination of different materials has a significant impact on the maximum stress and friction coefficients of gears.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2021)
Article
Thermodynamics
Hao Guo, Haitao Duan, Jianzhong Lei, Dongfeng Wang, Sanming Du, Yongzhen Zhang, Zongye Ding
Summary: This study conducted a failure analysis on the engine water pump shaft bearing using various methods, clarified the wear behavior and failure mechanisms, and proposed preventive measures. The failure of the bearing was reflected in the fracture of the bearing cage and serious wear of the roller and mandrel.
ADVANCES IN MECHANICAL ENGINEERING
(2021)
Article
Engineering, Mechanical
Zhongliang Xie, Jian Jiao, Kang Yang
Summary: Traditional water-lubricated bearings face challenges in forming effective lubricating film under extreme low-speed and heavy-duty conditions, leading to shortcomings such as low-load, high-resistance, high-vibration, and high-noise. The paper proposes a novel multi-field coupling lubrication model to investigate the mixed lubrication performances and critical characteristics of these bearings. By developing functional mapping relationships and building rotor dynamic models, the paper reveals the variation mechanisms of dynamic behaviors and verifies the correctness of the model and algorithm through theoretical analysis and experiment. The academic value of this research is expected to achieve a novel breakthrough in forming effective hydrodynamic film under extreme severe conditions for water-lubricated bearings.
TRIBOLOGY INTERNATIONAL
(2023)
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
Thermodynamics
Qianwen Huang, Xinping Yan, Cong Zhang
ADVANCES IN MECHANICAL ENGINEERING
(2018)
Article
Acoustics
Cong Zhang, Dongchen Xie, Qianwen Huang, Zhihua Wang
SHOCK AND VIBRATION
(2019)
Article
Engineering, Marine
Qianwen Huang, Huaiguang Liu, Zhe Ding
Summary: An appropriate assessment of the dynamical response of the marine propeller shaft is crucial for optimal power delivery to the propeller and minimizing unnecessary mechanical friction of supporting bearings. This study proposes a numerical model to analyze friction-induced vibration with velocity-dependent and stick-slip friction, and validates a Newton-Raphson & Newmark-fl solving method to solve the nonlinear model. The response of the dynamic friction coefficient, relative velocity, and reaction force are obtained, and an optimized design for the propeller shaft and supporting bearings is achieved based on the proposed numerical model.
Article
Engineering, Marine
Qianwen Huang, Zhihao Xie, Huaiguang Liu
Summary: This paper proposes an active control method based on a state observer to suppress the stick-slip behavior of the marine propeller shaft, aiming to improve the efficiency and reliability of the power system. The rotational speed of each segment of the shaft is tracked using state feedback and internal model principle. The behavior of the state observer is analyzed through a comparison of actual and observed values, and the robustness of the control system is investigated by comparing overshoot rate and adjustment time with different control parameters. The proposed frictional model is validated by comparing the observed velocity with previous reference, and active control of friction-induced vibration of the marine propeller shaft is achieved through adjustment of control parameters.
Article
Engineering, Marine
Qianwen Huang, Taotao Shang, Huaiguang Liu
Summary: A stable operating state of the marine shaft-bearing system is achieved through a semi-active control with PID strategy using an adjustable damping magnetorheological shock absorber and electromagnetic actuator. The harmonic response and controlled behaviors of the system are calculated and obtained through Matlab/Simulink. The proposed controller is demonstrated to be applicable and the controlled performance is discussed to prove its suitability.
Article
Engineering, Mechanical
Xin Shen, Qianwen Huang, Ge Xiong
Summary: This study proposes a method for estimating the vibration response of a propeller shaft and demonstrates its feasibility and accuracy through experiments. The research provides an easier maintenance method for predicting the real-time monitoring of propeller shaft vibration response.
MECHANICAL SCIENCES
(2022)
Article
Engineering, Marine
Qianwen Huang, Haiyun Liu, Jiyin Cao
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2019)
Article
Engineering, Chemical
Hongjuan Hou, Jiaxing Pei, Dongxing Cao, Leilei Wang
Summary: A numerical method is proposed to evaluate the effect of non-Gaussian roughness on point contact elastohydrodynamic lubrication (EHL). Based on the mixed EHL model, the influence of non-Gaussian roughness parameters on contact pressure distribution, film thickness profile, and the ratio of asperity pressure to contact load is investigated. The results show that the asperity pressure and film thickness increase as the non-Gaussian roughness parameters increase.
LUBRICATION SCIENCE
(2024)
