Article
Engineering, Mechanical
Mikael Miettinen, Valtteri Vainio, Rene Theska, Raine Viitala
Summary: The study experimentally investigated the performance and feasibility of a novel design for a robust air bearing with aerostatically sealed pressurized volume, and characterized its suitable operating domain based on load capacity, friction moment, chamber flow, and seal flow rate measurements under various conditions. The results provided corroborative evidence on the feasibility of the proposed chamber-based bearing design.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Engineering, Mechanical
Lei An, Wei Wang, Chaoqun Wang
Summary: A bidirectional fluid-structure coupling dynamic model is established to analyze the dynamic properties of high-speed aerostatic journal bearing with recess, by coupling the governing equation of the transient air film flow, the flow balance equation, and the rotor motion equation. The influences of operating parameters on the coupling system are theoretically and experimentally analyzed based on trajectory of rotor axis, trajectory of rotor center, Poincare map, time response of rotor, frequency spectrum, mass flow rate, and bifurcation diagram. The results indicate abundant nonlinear behavior and determine the instability parameters of the system. This study provides guidance for the theoretical design and practical operation of this type of system.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Acoustics
Xiao-Long Zhao, Hao Dong, Ya-Juan Wang, Bo Li
Summary: In this paper, a new model of aerostatic bearing in the form of microorifice annular array is designed, and the effects of orifice diameter on the pressure distribution of the bearing gas film and the static performance of the bearing are analyzed. The study finds that when the orifice diameter and the air film thickness are of the same order of magnitude, the stiffness of the aerostatic bearing is significantly improved, and the microporous throttled aerostatic bearing is more suitable for high stiffness applications.
SHOCK AND VIBRATION
(2022)
Article
Engineering, Mechanical
Abdurrahim Dal, Tuncay Karacay
Summary: This study examines the pneumatic hammer instability phenomena in the aerostatic journal bearing-rotor system and investigates the effects of different feeding hole configurations on the nonlinear dynamics of the system. Experimental results validate the numerical findings, indicating that the feeding hole configuration influences the pneumatic hammer instability region.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Manufacturing
Hui Zhuang, Jianguo Ding, Peng Chen, Yu Chang, Xiaoyun Zeng, Hong Yang, Xingbao Liu, Wei Wei
Summary: This paper investigates the influence of surface waviness on the performance of an aerostatic thrust bearing, with wave amplitude and rotational speed playing crucial roles. The sensitivity of bearing performance to surface waviness increases with wave amplitude, and high rotational speeds are more likely to cause pneumatic instability.
INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING
(2021)
Article
Engineering, Mechanical
Satish C. Sharma, Adesh Kumar Tomar
Summary: The study focuses on utilizing magneto-rheological fluid and micro-grooves to enhance the performance and stability of bearing systems, which is expected to assist in the design and analysis of bearing systems.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Thermodynamics
Zhiwei Lu, Xiyao Liu, Bo Liu, Junan Zhang
Summary: This paper proposes a multi-hole integrated restrictor (MIR) for investigating the lubrication characteristics of various restrictors on the aerostatic bearing. The numerical calculation and analysis of the gas film flow field at the orifice outlet of the MIR aerostatic bearing were conducted using the combined method of large eddy simulation and over-relaxation iteration. The results show that the lubrication performance of the multi-hole integrated restrictor is better than that of the single-orifice restrictor, and the fluctuation and micro-vibration of the flow field can be effectively reduced by setting the parameter of the multi-hole integrated restrictor.
ADVANCES IN MECHANICAL ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Qiang Gao, Siyu Gao, Lihua Lu, Min Zhu, Feihu Zhang
Summary: The article proposes a two-round optimization design method for aerostatic spindles considering the fluid-structure interaction (FSI) effect, aiming to improve the overall spindle performance by optimizing geometric parameters of the aerostatic bearings and key structural dimensions of the spindle. The optimal design parameters are obtained and experimentally verified, guiding the optimal design of aerostatic spindles considering the FSI effect.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Mechanical
Hailong Cui, Weiwei Gong, Yueqing Zheng, Yifei Li, Wei Wang, Zhengyi Jiang
Summary: This paper proposes a simplified FEM method based on MATLAB PDE tool to study the static performance of aerostatic journal bearings. The effects of bearings structural parameters and external supply pressure on film pressure distribution, load capacity, and static stiffness are investigated. An experimental platform with reversal structure is applied to reduce measurement error, with a maximum relative error between simulation and experimental results of 11.54%.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Abhishake Chaudhary, Arvind K. Rajput, Rajiv Verma
Summary: This study examines the effect of couple stress lubricant on an irregular journal bearing system, showing that the use of such lubricant can significantly improve the system performance.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Zhiwei Lu, Junan Zhang, Bo Liu
Summary: This study investigated the fluctuations of velocity and pressure in the flow field of an aerostatic bearing with a multi-hole integrated restrictor, focusing on the impact of orifice diameter and gas film clearance on the flow field. It was found that there is a critical ratio between gas film clearance and orifice diameter, which may serve as a crucial parameter for the transition from laminar to turbulent flow under a specified gas supply pressure.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Abdurrahim Dal, Tuncay Karacay
Summary: Aerostatic journal bearing applications in high-speed precision machining require predictable and smooth functioning. The size and blockage ratio of the orifices significantly affect the performance of the system, with partial blockage having either positive or negative effects depending on the feeding hole position.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
D. J. Ramos, G. B. Daniel
Summary: The new concept of hydrodynamic bearing can prevent fluid-induced instability in rotating systems, while also reducing oil temperature and bearing load capacity, showing great potential to enhance the performance of rotating machines.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Vladimir Kodnyanko, Stanislav Shatokhin, Andrey Kurzakov, Yuri Pikalov, Iakov Pikalov, Olga Grigorieva, Lilia Strok, Maxim Brungardt
Summary: Aerostatic bearings offer minimal friction losses, high durability, and environmental friendliness, but typically have low load-bearing capacity and high compliance. This study introduces a novel double-row aerostatic journal bearing with microgrooves to reduce compliance and improve load capacity, with experimental verification showing promising results. The proposed improvement significantly increases the load capacity of aerostatic journal bearings, making it a practical choice for future applications.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Mechanical
Penghai Zhang, Yizhen Peng
Summary: The study indicates that the motion accuracy of hydrostatic journal bearings mainly decreases with increasing rotation speed. The rotation speed affects the error motion amplitude but does not affect the selective action of the shaft wave number affecting the error motion. The accuracy theory can be used to predict error motion and choose the optimized recess number.
NONLINEAR DYNAMICS
(2021)
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)