Article
Engineering, Mechanical
Christoph Baum, Hartmut Hetzler, Simon Schroeders, Tim Leister, Wolfgang Seemann
Summary: A novel physical and mathematical model of foil air bearings was developed with a focus on computational time-efficiency for rotor dynamic investigations. The model, which accounts for nonlinear deformation behavior and linear viscous damping, was validated using published experimental data and reduction technique, showing a decrease in computation time up to a factor of 1000 with a slight loss in accuracy. The bearing model was also coupled with a rigid rotor model to demonstrate its applicability during a run-up and coast-down.
TRIBOLOGY INTERNATIONAL
(2021)
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
Acoustics
Jingyue Wang, Ning Liu, Haotian Wang, Lixin Guo
Summary: Based on a planetary gear transmission system considering the coupling effects of friction and elastohydrodynamic lubrication, a torsional dynamic model incorporating various factors such as friction, oil film, time-varying meshing stiffness, meshing damping, and gear backlash is established. The numerical results show that the system exhibits rich nonlinear dynamic characteristics such as short-period motion, long-period motion, and chaotic motion as the excitation frequency increases. The increase of lubricant viscosity, sun-planet backlash, and planet-ring backlash each have distinct effects on the system's dynamic behavior, influencing the occurrence of chaotic motion, periodic motion, and bifurcation characteristics.
JOURNAL OF LOW FREQUENCY NOISE VIBRATION AND ACTIVE CONTROL
(2021)
Article
Engineering, Chemical
H. C. Liu, F. Pape, Y. Zhao, L. Ellersiek, B. Denkena, G. Poll
Summary: The film-forming property of two commercial water-miscible MWFs is investigated and compared with two self-prepared O/W emulsions. The results show that the commercial MWFs lack the ability to form hydrodynamic films over the entire range of speeds used in this study, which is in contrast to the self-prepared emulsions.
Article
Engineering, Mechanical
Maximilian M. G. Kuhr, Rainer Nordmann, Peter F. Pelz
Summary: This study investigates the dynamic force and moment characteristics of annular gaps and carries out an extensive parameter study. A new simulation method is proposed to calculate the dynamic force and moment characteristics. The study shows that the annulus length, flow number, and modified Reynolds number are crucial for the relevance of the additional coefficients.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2023)
Article
Engineering, Mechanical
Zhongliang Xie, Yuxin Tian, Jiaxin Li, Peng Du
Summary: The paper aims to reveal the lubrication bearing mechanism of double-film bearing under different conditions. Modified lubrication models are established and the influences of coupling factors on lubrication characteristics are explored. The lubrication mechanism of the double-liquid film interface is elucidated.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Luis San Andres, Jonathan Toner, Andy Alcantar
Summary: Reducing the flow rate can decrease the operational costs and oil storage of tilting pad journal bearings, improving energy efficiency. However, excessively low oil flow can lead to temperature rises in the bearing pads and lubricating oil, which need to be monitored.
JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Mechanical
Felix C. von Plehwe, Corina Schwitzke, Hans-Joerg Bauer
Summary: This paper presents a method to measure heat transfer coefficients for oil injection cooled gears, inducing a temperature gradient between the gear and the hot oil. Experimental results show a characteristic behavior of the average heat transfer coefficient versus rotational speed.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Mechanical
Xueliang Lu, Luis San Andres, Jing Yang
Summary: This paper presents a nonhomogeneous bulk flow model for predicting the leakage and dynamic force coefficients of seals lubricated with gas in liquid mixtures. The model includes diffusion coefficients and a field equation for the transport of the gas volume fraction. Comparison with experimental data shows that the model offers a marked improvement in predicting the direct stiffness and has good agreement with the experimental results.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Energy & Fuels
Muhammad Imran Sadiq, Wan Aizon W. Ghopa, Mohd Zaki Nuawi, Mohammad Rasidi Rasani, Nor Kamaliana Khamis, Mohd Radzi Abu Mansor
Summary: This study evaluated the dynamic characteristics of bio-oils in journal-bearing applications and compared them with SAE40 lubricant. The results showed that bio-oils exhibited better responsiveness and lower cross-coupled stiffness coefficients, which reduced rotor instability.
Article
Chemistry, Multidisciplinary
Kei Kikuchi, Hiroyuki Mayama, Yoshimune Nonomura
Summary: This study investigated the friction properties of emulsions in an oral environment using a sinusoidal motion friction evaluation system that mimics the oral environment effectively. Different friction profiles were observed for various samples, with oil-in-water emulsions exhibiting asymmetric friction characteristics and lubrication phenomenon. The findings contribute significantly to understanding food-texture recognition mechanisms and dynamic phenomena on biological surfaces.
Article
Thermodynamics
Mubbashar Nazeer, A. Al-Zubaidi, Farooq Hussain, Faisal Z. Duraihem, Sadaf Anila, S. Saleem
Summary: This study examines the magnetohydrodynamics of a non-Newtonian fluid with heat transfer through a porous medium. The results show that a porous medium supports the flow Darcy number, while strong magnetic fields hamper the flow. The increase in thermal energy leads to a reduction in fluid velocity, and the temperature profile decreases with the varying permeability of the porous medium. A comparative analysis reveals that the Jeffrey multiphase suspension is more prominent than the Newtonian multiphase fluid.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Mechanics
K. Bouchorisa, V Bontozoglou
Summary: In this study, a surfactant-laden liquid film is used as a model of lung alveoli. The effects of film thickness and interface shearing velocity on alveolar dynamics are investigated. The results show that Marangoni stresses dominate the interfacial dynamics, while capillary stresses significantly affect the interior flow field. Adsorption kinetics also affects various variables including surface concentration, flow rate, and shear stress.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Engineering, Mechanical
Bin Wei, Yinghou Jiao, Xianglin Wu
Summary: The aim of this study is to present a technical numerical method to improve the efficiency of solving the Reynolds equation for hydrodynamic bearings. The developed method effectively combines the Bi-CGSTAB algorithm with the Reynolds boundary conditions to characterize the pressure distribution within the lubricant for hydrodynamic bearings.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Mechanical
Yongtao Zhang, Yupeng Liu, Junjun Deng, Rongxiang Song, Yingdan Zhu
Summary: This paper theoretically investigates the axial static and dynamic characteristics of hydrostatic worm-rack-drive, discussing the effects of pitch errors on its performance. A numerical calculation method is proposed based on an expanded view of the helicoid of threads, providing beneficial guidance for the design and performance optimization of hydrostatic worm-rack-drive.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Chemistry, Multidisciplinary
Qianqian Hu, Xian-Lei Shi, Yongju Chen, Feng Wang, Yujing Weng, Peigao Duan
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2019)
Article
Otorhinolaryngology
Bo Wang, Yu-jing Weng, Si-si Wang, Wen-xin Zhao, Shou-yi Yan, Li-yong Zhang, Jia Wen
HEAD AND NECK-JOURNAL FOR THE SCIENCES AND SPECIALTIES OF THE HEAD AND NECK
(2019)
Article
Engineering, Mechanical
Qihang Li, Weimin Wang, Fulei Chu
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2019)
Article
Engineering, Multidisciplinary
Wang WeiMin, Shao Xing, Li QiHang, Gao JinJi, Hao ZeRui
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2019)
Article
Thermodynamics
Guang Li, Ke Zhang, Bin Yang, Fan Liu, Yujing Weng, Zheyu Liu, Yitian Fang
Article
Chemistry, Physical
Longlong Wang, Yujing Weng, Xiaolong Wang, HongXing Yin, Fuchao Wang, Xiaoxiao Xue, Xianyun Liu, Feng Wang, Peigao Duan, Yulong Zhang
CATALYSIS COMMUNICATIONS
(2019)
Article
Thermodynamics
Guang Li, Zheyu Liu, Fan Liu, Bin Yang, Shuqi Ma, Yujing Weng, Yulong Zhang, Yitian Fang
ENERGY CONVERSION AND MANAGEMENT
(2019)
Article
Engineering, Mechanical
Kang Chen, Weimin Wang, Xulong Zhang, Ya Zhang
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2019)
Article
Engineering, Aerospace
Weimin Wang, Xulong Zhang, Dongfang Hu, Dengpeng Zhang, Paul Allaire
CHINESE JOURNAL OF AERONAUTICS
(2020)
Article
Engineering, Mechanical
Weimin Wang, Dongfang Hu, Qihang Li, Xulong Zhang
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2020)
Article
Acoustics
Qihang Li, Brian Weaver, Fulei Chu, Weimin Wang
JOURNAL OF SOUND AND VIBRATION
(2020)
Review
Engineering, Mechanical
Zhongsheng Chen, Hao Sheng, Yemei Xia, Weimin Wang, Jing He
Summary: The paper highlights the importance and challenges of blade tiptiming (BTT) technique as a method for blade vibration monitoring. It outlines the three main challenges faced by BTT technology, comprehensively reviews the developments of BTT probes, signal preprocessing, and vibration monitoring, and discusses future trends.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Construction & Building Technology
Xing Shao, Weimin Wang, Weibo Li, Qihang Li
Summary: This paper presents an active fast vibration control strategy for rotating machinery, which has been experimentally validated and implemented in a model to significantly reduce vibration amplitudes in a short period of time.
STRUCTURAL CONTROL & HEALTH MONITORING
(2021)
Article
Multidisciplinary Sciences
Longlong Wang, Yujing Weng, Peigao Duan, Xianyun Liu, Xiaolong Wang, Yulong Zhang, Chenguang Wang, Qiying Liu, Longlong Ma
SN APPLIED SCIENCES
(2019)
Article
Chemistry, Physical
Qingqing Li, Haiyong Wang, Zhipeng Tian, Yujing Weng, Chenguang Wang, Jianru Ma, Chaofeng Zhu, Wenzhi Li, Qiying Liu, Longlong Ma
CATALYSIS SCIENCE & TECHNOLOGY
(2019)
Article
Engineering, Mechanical
Huiyi Yang, Yang Xu, Chao Xu
Summary: This study focuses on the impact of dry friction interfaces on the dynamics of jointed structures, particularly on the statistics of contact pressure distribution. Through experimental and simulation analysis, it is found that surface roughness and contact load have significant effects on contact area, contact stiffness, and mean contact pressure.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)
Article
Engineering, Mechanical
Guanglan Hu, Houfu Dai
Summary: The effect of metal coating on the machinability of cubic silicon carbide was investigated using molecular dynamics simulation. The results showed that the type of coating has a significant impact on cutting force, surface morphology, stress, and tool wear. Among the three metals studied, Cu coating had the greatest impact on improving cutting performance.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)
Article
Engineering, Mechanical
Yunfan Liu, Guozheng Ma, Lina Zhu, Cuihong Han, Zhen Li, Bin Zhang, Haichao Zhao, Haidou Wang, Shuying Chen
Summary: The service performance of coated self-lubricating spherical plain bearings can be improved by applying self-lubricating coatings, especially double-sided coatings. The presence of a large-area and complete mixed friction transfer film on the contact surfaces can cause a signal downstage before the signal mutation stage.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)
Article
Engineering, Mechanical
Yakup Artun, C. Oktay Azeloglu, Gokhan Taylan
Summary: This article investigates the tribological properties of polymer journal bearings, particularly focusing on radial journal bearings made from UHMWPE and POM materials with different surface qualities. The study examines the performance of these bearings under varying load and speed conditions, and analyzes the relationship between material and surface roughness in tribological performance.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)