Article
Engineering, Mechanical
Tianming Ren, Ming Feng
Summary: In order to improve the stability problem of water lubricated journal bearings in high-speed conditions, the lobe pocket with an Archimedes helix profile was designed. The effects of radius clearance, pocket parameters, water supply pressure, restriction parameter, and external load were analyzed, considering turbulence. The results showed that decreasing radius clearance and increasing pocket depth improved bearing stability, while pocket widths had optimal values. Water supply pressure and orifice diameter increased the threshold speed at low speeds. The findings of this study provide valuable information for designing high-stability journal bearings.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Guangwu Zhou, Jinsheng Qiao, Wei Pu, Ping Zhong
Summary: The present study improves the conventional water-lubricated rubber bearing (WLRB) by using a tilting-pad structure and develops a mixed elastohydrodynamic (Mixed-EHD) model for water-lubricated rubber tilting-pad journal bearing (WLRTPJB). The study investigates the influence of structural and operating parameters on the tribological properties and pad swing characteristics. The results show that the WLRTPJB has a lower contact load, especially under heavy load conditions, and provide optimal pivot offset and preload factor to minimize contact pressure. Moreover, the equilibrium tilting-pad angle is sensitive to changes in design and operating parameters. This study has certain guiding significance for the design optimization of WLRB.
TRIBOLOGY INTERNATIONAL
(2022)
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
Jun Zha, Huijie Zhang, Dun Lyu
Summary: This study aims to address the issue of temperature rise in spindles by using substitutes in the spindle bearing material. Through application-oriented tests and temperature sensors, the researchers verified the relationship between water temperature increase and rotation speed, and demonstrated the potential of ceramic bearings in improving thermal stability of spindles.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2022)
Article
Engineering, Mechanical
Shouan Chen, Guo Xiang, Michel Fillon, Juan Guo, Jiaxu Wang, Jianlin Cai
Summary: This paper investigates the impact of imperfect journal on the tribo-dynamic behavior of water-lubricated bearings during start-up. The numerical model shows that the shape error of the journal can affect the performance of the bearing, but within a reasonable range, it can also improve the tribological performance.
TRIBOLOGY INTERNATIONAL
(2022)
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
G. H. G. van der Meer, F. Quinci, W. Litwin, M. Wodtke, R. A. J. van Ostayen
Summary: The study investigates the application of a modified MR fluid in lubrication performance using a journal bearing test bench. It is found that applying a local magnetic field can significantly reduce the transition speed of the bearing when lubricated with MR fluid, with only a minimal increase in friction. The lubricating performance of the MR fluid is compared to a reference oil.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Multidisciplinary
Wenjie Zhou, Yifan Wang, Guangkuan Wu, Bo Gao, Weibin Zhang
Summary: This paper presents a new numerical method, including finite element method and mixed method, to study the lubricated characteristics of journal bearing. The calculated results obtained by this method are validated and further research is conducted to investigate the effects of various parameters on the bearing performance. The stiffness and damping coefficients of the bearing are also calculated. The theoretical model and calculated results provide useful references for the design of journal bearing and rotor coupled system.
AIN SHAMS ENGINEERING JOURNAL
(2022)
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, Aerospace
Yu ZHOU, Longtao SHAO, Can ZHANG, Fenzhu JI, Jiang LIU, Guo LI, Shuiting DING, Qi ZHANG, Farong DU
Summary: This paper presents a simple experimental method to obtain the minimum film thickness and dynamic stiffness of bump-type foil journal bearing (BFJB) using the journal orbit. Results show that the experimental and numerical results fluctuate initially due to dry friction, but agree well once a gas film is generated to separate the shaft from the top foil. The proposed experimental method effectively predicts film thickness and dynamic characteristics, and can be used to predict rotor-bearing systems dynamics.
CHINESE JOURNAL OF AERONAUTICS
(2021)
Article
Engineering, Mechanical
Wojciech Litwin, Michal Wasilczuk, Michal Wodtke, Artur Olszewski
Summary: The goal of this paper is to investigate the wear properties of journal sliding bearings operating in contaminated water lubrication. The experimental tests were conducted on several bearing materials and bearing sleeve designs under typical operating conditions. The results show that water contamination has a significant impact on the wear of the bearing system. Some tested materials perform well in such conditions, demonstrating lower wear rates. The design of the bearing bush also affects the wear, with different designs made from the same material showing differences exceeding 100%. Higher water velocity in the lubricating grooves helps minimize the wear of the stainless steel shaft, which is also confirmed by numerical simulations.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Hengguan Zhang, Jianlin Cai, Tianyou Yang, Shouan Chen, Dongxing Tang, Jiaxu Wang
Summary: The study aims to investigate the impact of bearing waviness on the lubrication performances of coupled journal-thrust water-lubricated bearings using an elastohydrodynamic lubrication model. The numerical model is validated against published experimental data. The numerical model is used to calculate the load capacity and maximum fluid pressure under different parameters of bearing waviness, and then analyze the influence of bearing waviness on the performance of the bearings. Simulation results show that the waviness amplitude significantly affects the bearing performances, with a larger influence as the amplitude increases.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2023)
Article
Chemistry, Physical
Zhihao Li, Xiaoli Wang, Tie Fu, Yanqiang Hu, Lizhou Li, Zirui Zhao, Liyan Wu, Chenfei Wang, Shuaishuai Zhang
Summary: This study investigates the use of BaTiO3/polyimide (BTO/PI) nanocomposite films and lubricants to improve the tribological and electrification performance of the triboelectric speed sensor (TSS). A nano-film composite lubricated TSS (NFCL-TSS) is constructed and integrated with a bearing. The results show that the NFCL-TSS has lower mass loss, higher electrical output and stability compared to the TSS with pure PI under dry conditions, and can effectively monitor bearing skidding.
Article
Engineering, Mechanical
Tianyou Yang, Jianlin Cai, Liwu Wang, Dongxing Tang, Shouan Chen, Jiaxu Wang
Summary: The purpose of this study is to investigate the impact of turbulence on the lubrication performance of a coupled journal-thrust water-lubricated bearing with micro grooves. A numerical model is used to compare the results with published experimental data for validation. The study examines the variations in load capacity, maximum film pressure, and local Reynolds number with different operating conditions and micro groove depths.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2023)
Article
Chemistry, Multidisciplinary
Mingchen Qiang, Qi Zhao, Shaohang Yan, Xue Liu, Yu Hou, Tianwei Lai
Summary: The liquefaction of hydrogen plays a crucial role in the large-scale utilization of hydrogen energy. The performance of the hydrogen turbo-expander, a key refrigerating machine for high liquefaction efficiency, is directly affected by the hydrogen gas bearings. By numerically calculating and comparing the characteristics of herringbone grooved journal bearings under different lubricating gases, the study provides insights into the performance of hydrogen gas bearings. It is found that the performance of hydrogen gas bearings can be improved by adjusting working conditions, leading to increased load capacity and enhanced dynamic stability.
APPLIED SCIENCES-BASEL
(2022)
