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
Chemistry, Physical
Rajesh C. Shah, Rajiv B. Shah
Summary: This paper investigates the static and dynamic performance of ferrofluid lubricated long journal bearing, deriving a modified Reynolds equation by considering the flow behavior of the ferrofluid and continuity in the film region. The dimensionless expressions for load-carrying capacity, frictional force, coefficient of friction, stiffness coefficients, and damping coefficients are studied, showing a significant improvement in bearing performance compared to conventional lubricants.
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES
(2021)
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
Shaoyu Zhu, Xiangjun Zhang, Jun Sun, Dagang Wang
Summary: In this study, the static behavior of misaligned journal bearings under heavy loads was investigated using a non-Newtonian lubricant (pseudoplastic fluid with power-law relationship). The generalized average Reynolds equation for rough journal bearing under pseudoplastic lubricant flow was derived, using the average flow method of Patir and Cheng for model equation establishment. The numerical solution of bearing performance parameters was obtained using the finite difference method and the successive over-relaxation method, and it was found that surface roughness could partially compensate for the effects of liner elastic deformation and lubricant shear thinning. The derived generalized average Reynolds equation can be applied not only in the research of hydrodynamic lubrication but also in the research of mixed lubrication.
TRIBOLOGY INTERNATIONAL
(2023)
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
Jiayu Gong, Kun Liu, Yong Zheng, Fanming Meng
Summary: This study investigates the misalignment issue of journal bearings supporting planet gears and develops a thermal-elastohydrodynamic (TEHD) model to analyze and verify its behavior. The results show that reducing modification amount, helix angle, and radial clearance can enhance the TEHD performance of the bearing.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Juan Guo, Guo Xiang, Jiaxu Wang, Yankui Song, Jianlin Gai, Haiming Dai
Summary: This paper introduces a method of one-side profile modification for reducing the edge wear caused by journal defection in misaligned journal bearings. The effectiveness of the modification is confirmed through numerical calculations. The results indicate that the reasonable design of one-sided profile modification can increase the minimum film thickness at the edge of the bearing and reduce rough contact, thus improving the anti-wear performance of the misaligned journal bearing.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2022)
Article
Engineering, Mechanical
Hao Zhang, Xiaohui Lin, Shuyun Jiang
Summary: This study proposes a turbulent flow model considering the effects of turbulence and cavitation in water-lubricated bearings, and validates the model through simulations and experiments. The results demonstrate that both turbulence and cavitation effects have significant impacts on the static characteristics of the bearing.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2023)
Article
Engineering, Marine
Weixin Zhou, Yao Zhao, Hua Yuan, Jingxi Liu, Xiaoqiang Wang
Summary: This paper uses the influence coefficient factors method to analyze the contact pressure of misaligned bearings. The results show that the influence coefficient factors are greatly affected by the shape and constraints of the contact object. The proposed method is suitable for cylindrical shell contact analysis and has the same accuracy as FEM with half of the time consumption.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Mechanical
Jijo Jose, Niranjana Behera
Summary: The study shows that using dry powder lubricants can effectively eliminate oil degradation in hydrodynamic bearings under high temperatures and extreme conditions. The increase in ellipticity ratio affects the performance of three-lobed bearings, with larger powdered particles showing better load carrying capacity and stability compared to smaller particles.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Sanyam Sharma, Chimata M. Krishna
Summary: This study analyzed the stability of non-circular offset bearings using the finite element method, with selected input parameters such as eccentricity factor and aspect ratio. Output parameters including load, critical mass, whirl frequency ratio, and threshold speed were computed and plotted, showing that micropolar lubricated circular offset bearings exhibit high stability at higher eccentricity factors and aspect ratios.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Xiaohui Lin, Shun Wang, Shuyun Jiang, Shaowen Zhang
Summary: This study investigates the influence of interface effect and cavitation bubble distribution on the dynamic characteristics of high-speed water-lubricated spiral groove thrust bearings. A turbulent cavitating flow lubrication model is established based on two-phase fluid and population balance equation of bubbles. The stiffness and damping coefficients of the bearings are calculated using perturbation pressure equations. Experimental results validate the theoretical model. The findings suggest that the turbulent effect has a greater impact on the dynamic characteristics of the bearings compared to the cavitation effect.
CHINESE JOURNAL OF MECHANICAL ENGINEERING
(2022)
Article
Engineering, Mechanical
Woo-Ju Jeon, Sung-Ho Hong
Summary: A flexible structure is used to enhance the lubrication performance of a misaligned journal bearing. The bearing, which represents a sliding bearing, suffers damage from metal-to-metal contact caused by misalignment. To improve this issue, a journal bearing with a flexible structure is proposed. Numerical evaluation and elastohydrodynamic lubrication analysis considering elastic deformation are conducted, comparing lubrication performance based on variations in the flexible structure's geometry and minimum film thickness. Comparisons are also made between the journal bearing with and without the flexible structure. The flexible structure, in the form of a groove, is applied to the high load-bearing area of the journal bearing, experiencing elastic deformation through the generated oil film pressure to obscure a larger oil film. The numerical analysis demonstrates that the journal bearing with a flexible structure can enhance lubrication performance in misalignment conditions.
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
Mechanics
Yuanying Du, Jianying Lan, Hui Quan, Chenxi Sun, Xiaoyi Liu, Xueling Yang
Summary: By using four different turbulent lubrication mathematical models, the lubrication characteristics of water-lubricated rubber bearings under high-Reynolds-number operating conditions were studied. The turbulent lubrication models showed higher bearing capacity and film pressure compared to laminar lubrication models, and the Aokihiro-Harada Masahiro turbulent lubrication theory was found to be more accurate. Additionally, non-linear and approximately linear increases in bearing capacity and maximum film pressure were observed with increasing eccentricity and rotational speed, while non-linear decreases and approximately linear increases were observed with increasing clearance ratio.
Article
Engineering, Manufacturing
Xiangzhi Wang, Hun Guo, Jiyuan Tu, Songlin Ding
Summary: AGC-EDM is a high-speed EDM method utilizing active capacitive and powder mixing effects, with a proposed new discharge mechanism. Experimental results verify the capacitance characteristics and chain stacking process of graphene-kerosene dielectrics, and discuss material removal rate, relative electrode wear, and surface roughness with different process parameters.
JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME
(2021)
Article
Automation & Control Systems
Linglei Kong, Zhidong Liu, Xiangzhi Wang, Mingbo Qiu
Summary: The MA-DAP method proposed in this study is a novel approach for high-efficiency machining of titanium alloy, utilizing mixed-gas atomization discharge ablation processing. This method significantly increases material removal rate, reduces electrode wear, and improves machining quality.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Review
Computer Science, Interdisciplinary Applications
Sergio Tadeu Almeida, John P. T. Mo, Cees Bil, Songlin Ding, Xiangzhi Wang
Summary: The study discusses a synergistic combination of a novel machining technique WEDM with an industrial robot (IR) as the servo, successfully controlled through frequency modulation for machining hard-to-cut conductive materials yet free of vibration.
ARCHIVES OF COMPUTATIONAL METHODS IN ENGINEERING
(2022)
Article
Automation & Control Systems
Linglei Kong, Xiangzhi Wang, Qing He, Jinjin Han, Zhang Suorong, Ding Kai, Zhidong Liu
Summary: Experimental investigation of the titanium alloy die-sinking mixed-gas atomization discharge ablation process revealed four stages of micro-erosion process, and theoretical analysis showed the violent exothermic oxidation reaction between high-temperature melting material and oxygen medium introduced external chemical energy to achieve high particle removal power.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Materials Science, Paper & Wood
Yecheng Lin, Xiangzhi Wang, Longyu Wang, Da Yang, Huixia Lan
Summary: This study investigated the pH impact tolerance of a Fe-0/GO mediated anaerobic treatment system and found that the system exhibited a high CODCr removal rate and gas production, as well as favorable physicochemical properties of sludge under pH shock.
Article
Automation & Control Systems
Xiangzhi Wang, Mingbo Qiu, Hun Guo, Songlin Ding
Summary: This study introduces a novel powder-mixed multi-channel wire electrical discharge machining (WEDM) method to address the conflicting requirements of high material removal rate, high surface quality, and low energy consumption. The multi-channel discharge effect is utilized to disperse discharge energy and the new method significantly reduces surface roughness and thermal defects while maintaining a similar material removal rate as traditional WEDM.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Automation & Control Systems
Linglei Kong, Weining Lei, Jinjin Han, Qing He, Qilin Li, Zhang Suorong, Xiangzhi Wang, Zhidong Liu
Summary: This article analyzes the oxidation characteristics and structural characteristics of the oxide layer formed on the surface of titanium alloy, reveals the reasons for the combustion and explosion phenomena during titanium alloy machining, and proposes a mixed-gas electrical discharge ablation processing method to avoid explosions.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Allergy
Xiangzhi Wang, Chengyun Xu, Yuqing Cai, Xinyi Zou, Yunqi Chao, Ziyi Yan, Chaochun Zou, Ximei Wu, Lanfang Tang
Summary: This study revealed the high expression of circZNF652 in bronchoalveolar lavage fluid of allergic asthma patients and its role in promoting pathological goblet cell metaplasia through activation of the miR-452-5p/JAK2/STAT6 signaling pathway. These findings provide new strategies for the therapeutic intervention of epithelial remodeling in allergic airway inflammation.
JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY
(2022)
Article
Engineering, Manufacturing
Xiangzhi Wang, Hun Guo, Ge Wu, Songlin Ding
Summary: This paper explores the potential of improving the processability of PCD by utilizing the moving electric arcs formed by dielectric flushing. Mathematical models were established and experiments conducted to investigate the behavior of plasma channels. The results show that dielectric flushing can stretch the plasma channel, change the arc spots, and improve material removal rate and surface topography consistency.
MATERIALS AND MANUFACTURING PROCESSES
(2022)
Article
Multidisciplinary Sciences
Linglei Kong, Weining Lei, Qun Wei, Jinjin Han, Zhang Suorong, Qilin Li, Xiangzhi Wang, Zhidong Liu
Summary: The die-sinking mixed-gas atomization discharge ablation process (DMA-DAP) uses an atomized dielectric formed by a mixed gas and water medium to achieve highly efficient erosion. Compared to electrical discharge machining (EDM), DMA-DAP has a significantly higher material removal rate and better surface morphology.
SCIENTIFIC REPORTS
(2022)
Review
Engineering, Manufacturing
Xiangzhi Wang, Chaojiang Li, Hun Guo, Songlin Ding
Summary: This paper provides an overview of methods and technologies to improve the efficiency and surface quality of PCD machining, along with their underlying mechanisms. Increasing energy utilization and sparking gap can enhance machining efficiency. Further improvements can be made by changing processing forms, dielectrics, electrode shapes, and power generators.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE
(2022)
Article
Multidisciplinary Sciences
Dan Tan, Meiping Lu, Yuqing Cai, Weibo Qi, Fugen Wu, Hangyang Bao, Meiyu Qv, Qiangqiang He, Yana Xu, Xiangzhi Wang, Tingyu Shen, Jiahao Luo, Yangxun He, Junsong Wu, Lanfang Tang, Muhammad Qasim Barkat, Chengyun Xu, Ximei Wu
Summary: Allergic asthma is characterized by goblet cell metaplasia. Here, the authors show protein SUMOylation contributes to goblet cell metaplasia and SUMOylation-mediated ROCK2 activation is an integral component of Rho/ROCK signaling pathway in controlling the airway goblet cell metaplasia.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Environmental
Huixia Lan, Linyu Ji, Ke Li, Yecheng Lin, Xiangzhi Wang, Wudi Zhang, Qiaochu Liang, Yang Zhang
Summary: In this study, a Fe0/GO composite was used to improve the traditional anaerobic treatment process. Results showed that Fe0/GO enhanced COD removal rate, gas production, and sludge flocculation performance. Furthermore, it altered fermentation type, resulting in increased acetic acid production and reduced propionic acid accumulation. Fe0/GO also had a significant effect on microbial communities, maintaining a stable co-metabolizing microbial community. Additionally, it improved both intracellular and interspecific electron transfer, promoting anaerobic wastewater treatment. This study provides theoretical support for the practical application of anaerobic wastewater treatment technologies.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
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)
