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
Chemistry, Multidisciplinary
Jia Xie, Chengyu Peng, Wenshan Zhang, Cun Zhao, Quanke Feng
Summary: This study focuses on the technical obstacles of the star wheel axial thrust bearings used in water-lubricated single-screw compressors, proposing a structural optimization pattern with a new liquid groove. The reasonableness and effectiveness of the proposed model were verified through simulations and experiments, providing insight into improving the performance and longevity of water-lubricated single-screw compressors.
APPLIED SCIENCES-BASEL
(2021)
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
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
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
Mechanics
Chandan Kumar, Somnath Sarangi
Summary: Theoretical investigation on the planar dynamics of a rotor supported by self-acting gas-lubricated journal bearing system revealed the effects of whirling and critical parameter ranges for safe operation. Analysis of dynamic behavior under varying parameters demonstrated stability and limit cycle oscillations under different conditions. Results were validated through numerical integration of trajectories for different initial conditions, showing equilibrium point bifurcation and limit cycle bifurcations in the system dynamics.
MECHANICS RESEARCH COMMUNICATIONS
(2022)
Article
Computer Science, Interdisciplinary Applications
Wonvin Kim, Su Hyun Lim, Hyunsoo Hong, Kwang Il Jeong, Seung Yoon On, Seong Yeon Park, Jun Il You, Seong Su Kim
Summary: This study analyzed the effects of turbulence, inertial effect, and elastic deformation on a water-lubricated composite journal bearing system. The Reynolds equation and constitutive equation were modified and solved using the finite difference method and finite element method, respectively. The normalized minimum film thickness was modeled based on the Gaussian regression model, and new optimal maximum load-carrying capacity boundaries were proposed.
JOURNAL OF COMPUTATIONAL DESIGN AND ENGINEERING
(2022)
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
Thermodynamics
Chuang Wang, Mingkun Liu, Bingqi Wang, Ziwen Xing, Yue Shu
Summary: A mathematical model is constructed to analyze the power consumption distribution in different positions of a water-lubricated twin-screw air compressor at different rotating speeds. The results show that thrust bearings account for the largest power loss, while water vapor has the least impact, which is different from common oil-injected twin-screw compressors.
Article
Green & Sustainable Science & Technology
Emillo Byrd, Benjamin Netzel, David Brent Adams, Hao Zhang
Summary: This study evaluated the global warming potentials of magnetic bearing chillers and oil lubricated bearing systems throughout their life cycle stages. Results showed that magnetic bearing systems performed better in terms of life cycle GHG emissions, mainly due to their higher compressor efficiency during the use stage.
JOURNAL OF INDUSTRIAL ECOLOGY
(2021)
Article
Engineering, Mechanical
J. C. Atwal, R. K. Pandey
Summary: This paper explores the performance parameters of a sector-shaped pad thrust bearing lubricated with water using a new pocket design, considering the effects of turbulence and cavitation. The study investigates the effects of new pocket attributes and compares the performance behaviors achieved with the new pocketed pad bearing with plain pad and rectangular pocketed bearing.
TRIBOLOGY INTERNATIONAL
(2021)
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)
Article
Engineering, Mechanical
Krishnkant Sahu, Satish C. Sharma, Adesh Kumar Tomar
Summary: This paper proposes a study on the slot-entry 'hybrid conical journal bearing system' (HCJBs) with the slot restrictor as a compensating device. The effects of different zonal arrangements of textured surfaces and smart behavior of magnetorheological fluid (MRF) on the HCJBs are analyzed. Mathematical modeling of the modified Reynolds equation is done using the Finite element method and the Gauss-Seidel method. Numerical simulation shows that the application of textured surfaces and MR fluid improves the performance of the hybrid conical bearing system in terms of fluid film thickness, stiffness, and stability.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Tianming Ren, Ming Feng
TRIBOLOGY INTERNATIONAL
(2017)
Article
Engineering, Electrical & Electronic
Xiaojun Ren, Ming Feng, Tianming Ren
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
(2019)
Article
Engineering, Mechanical
Hongyang Hu, Ming Feng, Tianming Ren
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2020)
Article
Engineering, Mechanical
Ming Feng, Hongyang Hu, Tianming Ren
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2020)
Article
Engineering, Mechanical
Hongyang Hu, Ming Feng, Tianming Ren
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2020)
Article
Engineering, Mechanical
Hongyang Hu, Ming Feng, Tianming Ren
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2020)
Article
Engineering, Mechanical
Hongyang Hu, Ming Feng, Tianming Ren
Summary: A new type of gas foil conical bearing was proposed to reduce the mass and size of low-power turbine machinery, with its static and dynamic performance systematically studied. The results show that the new bearing has excellent supporting performance and broad prospects for application, with parameters such as bump radius, rounding radius, friction coefficients, and foil thickness significantly influencing the bump foil stiffness.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Hongyang Hu, Ming Feng, Tianming Ren
Summary: This study investigates the characteristics of gas foil conical bearings (GFCBs) under misalignment, analyzing the static and dynamic performances in different misalignment cases. Findings show that the supporting performance of GFCB is excellent, with the film clearance playing a critical role. Misalignment effects depend on the assembled angle and the misalignment angle, with larger misalignment angles leading to more dramatic effects.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Xiaojun Ren, Ming Feng, Tianming Ren
Summary: This study focuses on the magnetic field analytical calculation method for combined radial and axial magnetic bearings. The effectiveness of the analytical method is verified by finite element and experimental results.
IET ELECTRIC POWER APPLICATIONS
(2023)
Article
Engineering, Mechanical
Hongyang Hu, Ming Feng, Tianming Ren
Summary: The addition of shim foil under the bump foil of gas foil journal bearings (GFJBs) can significantly increase the load capacity and direct stiffness, especially with the presence of preload, while also improving stability. The stability threshold speed (STS) of rotors supported by the novel GFJBs is enhanced, indicating better stability.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Proceedings Paper
Engineering, Mechanical
Ming Feng, Tianming Ren
APPLIED MECHANICS, MATERIALS AND MANUFACTURING IV
(2014)
Article
Engineering, Mechanical
Busra Duran, Jerome Cavoret, David Philippon, Fabrice Ville, Arnaud Ruellan, Frank Berens
Summary: This study analyzes the changes in the physicochemical properties and tribological performances of gear transmission oils during field operation, finding differences from traditional engine oils.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Baocheng Liu, Hongsheng Chen, Jun Zhou, Jing Wang, Wenxian Wang, Xiaochun Chen, Sanxiao Xi
Summary: This study used fast hot pressing sintering to fabricate WC/AlCoCrFeNi2.1 metal matrix composites (MMCs). It was found that the addition of reinforced particles increased the microhardness, nanoindentation and wear resistance of the MMCs. During frictional processes, an oxide film formed, providing material protection, enhancing stability and reducing friction-induced losses.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Pradip Kumar Verma, Alok Singh
Summary: This study investigates the mechanical properties and wear resistance of CoMoMnNiV high entropy alloy reinforced aluminium matrix composite processed through stir-squeeze casting assisted with an ultrasonic transducer. The results show significant improvements in mechanical properties and wear resistance, with the composite containing 8 wt% HEA demonstrating the highest resistance to wear. Optical microscopy, SEM, and an optical profilometer were used for a thorough examination of the microstructure and worn surface.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Zhenghai Yang, Yingjian Song, Jinlong Jiao, Wenbo Li, Bao Shangguan, Yongzhen Zhang
Summary: This study investigated the friction, wear properties, and current-carrying properties of copper-graphite composites paired with brass C28000. The results showed that the current-carrying properties of the composite materials were excellent, but their wear rate was the main limiting factor. Furthermore, an increase in the thickness of the graphite layer led to an improvement in the uniformity of damage.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Moustafa Mahmoud Yousry Zaghloul, Karen Steel, Martin Veidt, Michael T. Heitzmann
Summary: This research evaluates and compares the impact of different material types on the tribological characteristics of Polyamide 6 composites, and finds that glass fiber-reinforced Polyamide 6 exhibits better friction and wear performance under high-pressure velocity factors.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Shaoqing Qin, Lida Zhu
Summary: In this paper, the surface and subsurface damage of laser assisted grinding CrCoNi medium entropy alloys were investigated using molecular dynamics simulations. The results showed that the application of laser energy can reduce cutting forces and minimize subsurface damage.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Kaikui Zheng, Youxi Lin, Tingzheng Lai, Chenghui Gao, Ming Liu, Zhiying Ren
Summary: The study investigated the use of waste foundry resin-bonded sand as a substitute for copper in resin-based brake material. It found that the waste sand was more favorable for improving the overall friction and wear properties of the material compared to copper. Waste sand benefited the material by forming a friction layer, leading to increased friction coefficient and stability. Brake material with 10-15% waste sand showed excellent heat-fade resistance.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Dayang Li, Fanhao Zhou, Yutong Gao, Kun Yang, Huimin Gao
Summary: This article introduces a continuous prediction model based on deep learning for predicting the power output of steam turbines. The model uses long short term memory (LSTM) method to develop a trend prediction model and optimizes the prediction model through feature selection method. Experimental results show that the model outperforms other models in terms of prediction performance.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Tomohiro Toyoda, Ryo Yasuike, Toshihiro Noda
Summary: In this study, a elasto-plastic constitutive model of friction incorporating the concept of superloading surface was developed based on the subloading friction model. The proposed model achieves a smooth transition of friction by describing the evolution rule of structure, treating the state with static friction coefficient larger than kinetic friction coefficient as the bulkiness of structure. The positive definiteness of the plastic multiplier, loading condition, and material parameters were derived, and the validity of the proposed model in accordance with the subloading-friction model was confirmed through a stick-slip simulation of a mass-spring system.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
P. Balaji, B. Surya Rajan, K. Sathickbasha, P. Baskara Sethupathi, Deviga Magadevan
Summary: This study emphasizes the importance of using a variety of solid lubricants with different oxidation temperature regimes to enhance the tribological performance of brake pads.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Jian Ma, Yancong Liu, Javad Mostaghimi, Na Zhang
Summary: This paper investigates the influence of preparation strategies on the lubrication properties of surface textures. Three laser scanning strategies are proposed to achieve a sinusoidal textured surface, and the evolution of surface structure and chemical composition is discussed. The findings show that ridge structures enhance anti-wear properties but also increase the friction coefficient. However, the oil cover preparation method prevents the formation of ridges and improves wettability.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Mohammad Roostaei, Arvin Taghizadeh Tabrizi, Hossein Aghajani
Summary: In this research, the Al2O3/MoS2 nanocomposite coating layer was successfully applied on the surface of Ti-6Al-4 V alloy. The relation between the surface characteristics and wear resistance of the coating was studied using atomic force microscopy analysis and pin-on-disk wear test method. The results showed that the nanocomposite coating significantly reduced the wear rate and provided an equation to calculate the Lancaster coefficient.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Musa Bilgin, Sener Karabulut, Halil Karakoc, Yunus Kayir, Murat Sarikaya
Summary: This study investigates various methods to improve the machinability efficiency of Inconel 718 alloy while considering their effect on microstructural properties. The results show that hot+PMQL, hot+SiCNMQL, and hot+Al2O3-NMQL contribute significantly to the improvement of machinability characteristics. The EBSD analysis also reveals that a limited area is affected by heat in the hot machining environment and that the removal of the heated layer during milling process helps preserve the microstructure.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Q. Gao, Y. Fan, Y. G. Wu, J. L. Liu, J. Wang, L. Li
Summary: Fretting wear significantly affects the hysteresis behavior of the contact surface and leads to joint degradation. This study investigates the influence of harmonic normal force on the evolution of interface morphology and contact parameters with fretting wear. The results show that the harmonic normal force can significantly influence the hysteresis loop and the energy dissipation distribution on the contact surface.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Benjamin Weiland, Floriane Leclinche, Anis Kaci, Brigitte Camillieri, Betty Lemaire-Semail, Marie -Ange Bueno
Summary: This study presents a systematic approach to generating control signals for a tactile simulator that simulate the touch of textile fabrics. By using a friction modulation tactile surface and acquiring forces from real surfaces with artificial finger mimicking fingerprints, control signals are generated and processed in the frequency domain before sending them to the tactile stimulator. The study focuses on the potential benefits of incorporating fingerprint information in fabric simulations to achieve a more realistic tactile perception. A sensory analysis with 36 participants using the generated control signals showed better discrimination without fingerprint information.
TRIBOLOGY INTERNATIONAL
(2024)