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
Hong Guo, Jianqiao Bao, Shaolin Zhang, Minghui Shi
Summary: This paper presents a misaligned journal mixed lubrication model coupling for multiple factors, and applies the finite difference method to calculate the model and experimental validation. The results show that under misalignment conditions, the pressure field, film thickness, and elastic deformation of the bearing have asymmetric distribution and end side effect. Additionally, the frictional force and side leakage flow are enhanced with the increase in inclination angle within a certain range.
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
Fangrui Lv, Chunxiao Jiao, Qian Jia, Kang Xia
Summary: This paper establishes a mixed lubrication model for water-lubricated polymer bearings considering the effect of journal misalignment, liner elastic deformation, and local turbulence. The influence of key structural and operating parameters on the bearing performance with journal misalignment is investigated.
Article
Engineering, Mechanical
Jian Jin, Xiaochao Chen, Yiyang Fu, Yinhui Chang
Summary: This study explores the combined effects of boundary slip and texture on hydrodynamic journal bearings. The optimized patterns of slip and texture can substantially improve the performance of journal bearings. The location and size of the slip and texture zones have a significant impact on journal bearings, with different texture-slip combinations affecting load-carrying capacity and friction reduction.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Krishnkant Sahu, Satish C. Sharma, Nathi Ram
Summary: Misalignment affects the operation of the journal bearing system, and smart lubricants can enhance the performance of fluid film bearings. The study finds that journal misalignment reduces the fluid film thickness, increases the fluid film damping coefficient, and frictional torque.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
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
Biao Li, Jun Sun, Hu Wang, Xiao Zhang
Summary: This paper analyzes the lubrication performance of journal bearing considering the axial movement of the journal, and finds that the axial movement has a significant influence on the lubrication characteristics of misaligned journal bearing.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(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
Ruichao Liu, Lilong Jing, Xianghui Meng, Bugao Lyu
Summary: The study showed that the bearings of the hermetic rotary compressor work under high ambient pressure, and taking into account the deformation of the crankshaft can more accurately estimate the wear of the thrust bearing. Furthermore, high ambient pressure is the leading cause of thrust bearing wear.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Arun Bangotra, Sanjay Sharma, Reza Taufique, Deepak Byotra
Summary: The present study investigates the influence of surface waviness on the performance of a journal bearing operating in misaligned conditions. The finite element method is utilized to compute the lubricant pressure within the bearing and obtain the static parameters. Comparison is made between different waviness variables and a misaligned journal bearing without surface waviness. It is found that misalignment in both axes has a more severe effect on static performance parameters compared to misalignment in only one axis.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2023)
Article
Engineering, Mechanical
Edoardo Gheller, Steven Chatterton, Daniele Panara, Gabriele Turini, Paolo Pennacchi
Summary: This paper applies artificial intelligence (AI) to predict the behavior of tilting pad journal bearings (TPJBs) using a trained deep learning (DL) model, which can quickly and accurately predict the dynamic and static characteristics of TPJBs compared to traditional models.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Mohammad Arif, Saurabh Kango, Dinesh Kumar Shukla
Summary: This study investigates the combined influence of slip boundary condition and non-Newtonian lubricants on the tribological performance of hydrodynamic textured journal bearing. The modified Reynolds equation with considering the Elrod cavitation model is solved to accurately predict the effect of air/vapor bubble formation in the diverging zone of the slip-texture bearing. The results show that changing the rheology of the lubricant from Newtonian to Pseudoplastic significantly improves the maximum pressure, average rise in temperature, and lubricant-bearing friction-force of the slip-texture bearings.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Review
Engineering, Mechanical
Sitae Kim, Dongil Shin, Alan B. Palazzolo
Summary: This review summarizes the effects of nonlinear elements in fluid film journal bearings on rotor-bearing systems, including sub- and super-synchronous, chaos and thermally induced instability responses. It also discusses the importance of nonlinear, thermo-elasto-hydrodynamic aspects of journal bearings in high-performance turbomachines, and presents nonlinear solution methodologies and numerical tools for analyzing nonlinear vibration responses induced by bearings.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Mechanical
Guoqing Xiong, Zhiwei Mao, Jinjie Zhang, Zijia Wang, Huailei Wang, Zhinong Jiang
Summary: Numerous studies have shown that both journal misalignment and bearing elastic deformation significantly affect lubrication performance. Recent research indicates that viscoelastic deformation is more useful than elastic deformation for determining the effects of strong impact loads. However, there have been no studies on the coupled effects of misalignment and viscoelastic deformation. Therefore, this study proposes a novel transient lubrication model that considers the influences of both misalignment and viscoelastic deformation, and investigates their coupled effects on lubrication performance.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
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)