Pub Date : 2023-11-03DOI: 10.1177/13506501231210595
Ao Zhong, Weimin Tang, Ligang Yao, Ling Pan, Jun Zhang
A proper running-in process is necessary for double circular-arc spiral bevel gears to achieve desirable meshing performance. However, this type of gear transmission lacks a suitable running-in wear model, which brings great difficulties to the design of appropriate running-in strategies. To address this problem, the present study establishes an efficient numerical wear model to reveal the wear behavior of double circular-arc spiral bevel gear pairs, based on which a step-wise load running-in strategy is proposed. The established Archard's wear model considers the meshing characteristics of double circular-arc spiral bevel gears and sets a small threshold value, which can reflect the wear behavior of this gear in the running-in stage. To improve the computation efficiency, a two-step parameter updating strategy is proposed to enhance the iteration of p and s. The wear simulation reveals the quantitative relationship contact pressure and running-in cycle during the running-in process. Based on the reveal relationship, a step-wise load running-in strategy is proposed to sharpen the running-in period. The developed wear model and the proposed running-in strategy can be extended to other types of gears with circular-arc profiles.
{"title":"A running-in strategy based on an efficient wear simulation model for double circular-arc spiral bevel gears","authors":"Ao Zhong, Weimin Tang, Ligang Yao, Ling Pan, Jun Zhang","doi":"10.1177/13506501231210595","DOIUrl":"https://doi.org/10.1177/13506501231210595","url":null,"abstract":"A proper running-in process is necessary for double circular-arc spiral bevel gears to achieve desirable meshing performance. However, this type of gear transmission lacks a suitable running-in wear model, which brings great difficulties to the design of appropriate running-in strategies. To address this problem, the present study establishes an efficient numerical wear model to reveal the wear behavior of double circular-arc spiral bevel gear pairs, based on which a step-wise load running-in strategy is proposed. The established Archard's wear model considers the meshing characteristics of double circular-arc spiral bevel gears and sets a small threshold value, which can reflect the wear behavior of this gear in the running-in stage. To improve the computation efficiency, a two-step parameter updating strategy is proposed to enhance the iteration of p and s. The wear simulation reveals the quantitative relationship contact pressure and running-in cycle during the running-in process. Based on the reveal relationship, a step-wise load running-in strategy is proposed to sharpen the running-in period. The developed wear model and the proposed running-in strategy can be extended to other types of gears with circular-arc profiles.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"42 22","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135868101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, an extended Reynolds equation incorporating the shape errors and the inertia effects of compressible fluid was formulated. The pressure-solving equation for the gas film was constructed using a second-order finite difference method. By combining the measurement data from the cylindricity of multiple shafts obtained from a cylindricity measuring instrument, the variation of the aerostatic bearing load capacity with the rotation of the shaft was calculated, both with and without considering the inertia effect. An experimental rig was also constructed to measure the error motion data of the corresponding shaft. The results of numerical analysis and experimental validation demonstrated that shafts with larger cylindricity error values exhibit greater deviations in the calculated bearing load capacity, which correspondingly leads to larger radial error motion values measured in the experiment. When the roundness error value of the shaft is small or the shaft speed is low, the influence of inertial effects on the calculation results of the load capacity deviation is minimal and can generally be disregarded.
{"title":"Influence of shape errors and inertia effects on the error motion of the aerostatic spindle","authors":"Guoqing Zhang, Jianming Zheng, Hechun Yu, Ting Chen, Shijie Shan, Chao Peng","doi":"10.1177/13506501231211393","DOIUrl":"https://doi.org/10.1177/13506501231211393","url":null,"abstract":"In this study, an extended Reynolds equation incorporating the shape errors and the inertia effects of compressible fluid was formulated. The pressure-solving equation for the gas film was constructed using a second-order finite difference method. By combining the measurement data from the cylindricity of multiple shafts obtained from a cylindricity measuring instrument, the variation of the aerostatic bearing load capacity with the rotation of the shaft was calculated, both with and without considering the inertia effect. An experimental rig was also constructed to measure the error motion data of the corresponding shaft. The results of numerical analysis and experimental validation demonstrated that shafts with larger cylindricity error values exhibit greater deviations in the calculated bearing load capacity, which correspondingly leads to larger radial error motion values measured in the experiment. When the roundness error value of the shaft is small or the shaft speed is low, the influence of inertial effects on the calculation results of the load capacity deviation is minimal and can generally be disregarded.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"41 20","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135867949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Additive manufacturing (AM) is a newly developed technology for manufacturing parts from three-dimensional (3D) computer-aided design (CAD) models by depositing a material layer on layer. Multi-jet fusion (MJF) is one of the AM technologies that can be used for manufacturing functional parts like gear, linear, bearing, etc., by polymers. In various applications, technical processes, design of tribological systems, optimum lubrication, and reduction of wear and friction are significant performance criteria to provide energy and material conservation. The development of green tribological applications offers essential solutions to problems of ecosystem pollution and energy from a global point of view to increase sustainability. In this article, the green tribological behavior of Polyamide 12 (PA12) parts, manufactured by MJF with different build orientations was evaluated by ball-on-disc tribological tests under different normal loads and lubricated environments. Mechanical profilometer and digital microscope were used to evaluate surface quality and morphology. Scanning electron microscope (SEM) was used to determine the samples’ wear characteristics. The maximum surface roughness was measured for the part having a build orientation of 45°. The maximum coefficient of friction value was determined as 0.355 for the sample with 45° orientation under 5 N load and dry environment. The maximum wear rate value was determined as 2.3249 × 10 −4 mm 3 /Nmm for the sample with 0° orientation under 10 N load and dry state. The differences between build orientations should be considered when evaluating tribological properties. This article provides a new perspective to researchers and practitioners toward green tribology of polymer AM parts.
增材制造(AM)是一种新发展起来的技术,通过一层一层地沉积材料,从三维(3D)计算机辅助设计(CAD)模型制造零件。多射流融合(MJF)是一种增材制造技术,可用于制造功能部件,如齿轮,线性,轴承等,由聚合物。在各种应用中,技术流程、摩擦学系统的设计、最佳润滑、减少磨损和摩擦是提供能源和材料节约的重要性能标准。绿色摩擦学应用的发展从全球的角度为生态系统污染和能源问题提供了必要的解决方案,以提高可持续性。在不同的正常载荷和润滑环境下,通过球盘摩擦试验,对MJF公司生产的具有不同构造取向的聚酰胺12 (PA12)零件的绿色摩擦学性能进行了评价。采用机械轮廓仪和数码显微镜对表面质量和形貌进行评价。采用扫描电镜(SEM)对试样的磨损特性进行了分析。最大表面粗糙度测量的部分具有45°的构建方向。在5 N载荷和干燥环境下,45°取向试样的最大摩擦系数为0.355。在10 N载荷和干燥状态下,0°取向试样的最大磨损率为2.3249 × 10−4 mm 3 /Nmm。在评估摩擦学性能时,应考虑构建方向之间的差异。本文为高分子增材制造零件的绿色摩擦学研究提供了新的视角。
{"title":"Effect of build orientation on the green tribological properties of multi-jet fusion manufactured PA12 parts","authors":"Beyza Gavcar, Emir Halit Sumer, Binnur Sagbas, Jitendra Kumar Katiyar","doi":"10.1177/13506501231209396","DOIUrl":"https://doi.org/10.1177/13506501231209396","url":null,"abstract":"Additive manufacturing (AM) is a newly developed technology for manufacturing parts from three-dimensional (3D) computer-aided design (CAD) models by depositing a material layer on layer. Multi-jet fusion (MJF) is one of the AM technologies that can be used for manufacturing functional parts like gear, linear, bearing, etc., by polymers. In various applications, technical processes, design of tribological systems, optimum lubrication, and reduction of wear and friction are significant performance criteria to provide energy and material conservation. The development of green tribological applications offers essential solutions to problems of ecosystem pollution and energy from a global point of view to increase sustainability. In this article, the green tribological behavior of Polyamide 12 (PA12) parts, manufactured by MJF with different build orientations was evaluated by ball-on-disc tribological tests under different normal loads and lubricated environments. Mechanical profilometer and digital microscope were used to evaluate surface quality and morphology. Scanning electron microscope (SEM) was used to determine the samples’ wear characteristics. The maximum surface roughness was measured for the part having a build orientation of 45°. The maximum coefficient of friction value was determined as 0.355 for the sample with 45° orientation under 5 N load and dry environment. The maximum wear rate value was determined as 2.3249 × 10 −4 mm 3 /Nmm for the sample with 0° orientation under 10 N load and dry state. The differences between build orientations should be considered when evaluating tribological properties. This article provides a new perspective to researchers and practitioners toward green tribology of polymer AM parts.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"266 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135273665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-30DOI: 10.1177/13506501231207126
Wassem Gerges, Oliver Heipl, Marc Wettlaufer, Dirk Bartel
As the clutch friction stability in dual-clutch transmissions has been continuously improved over the last decade, wear protection of high loaded mechanical contacts has become increasingly important and mechanical failures have been observed at the end of extended oil drain intervals. A test method was established based on standard equipment already used for transmission fluid development. A modified FZG four-square test rig allows ageing a reduced oil volume to not decelerate development times. Applicability was demonstrated by ageing four full formulated transmission fluids using the new approach and comparing the results to aged transmission fluids sampled from durability testing. The oils aged with the FZG rig exhibit the same characteristics of scuffing load capacity degradation as observed in full transmission systems. However, in the full transmission system, the degradation starts at lower applied specific work, most likely due to the different system complexity. It is pointed out that not only the thermal load but also the tribological stresses have to be considered to mimic oil ageing.
{"title":"Impact of oil ageing on gear scuffing in hybrid dual-clutch transmissions","authors":"Wassem Gerges, Oliver Heipl, Marc Wettlaufer, Dirk Bartel","doi":"10.1177/13506501231207126","DOIUrl":"https://doi.org/10.1177/13506501231207126","url":null,"abstract":"As the clutch friction stability in dual-clutch transmissions has been continuously improved over the last decade, wear protection of high loaded mechanical contacts has become increasingly important and mechanical failures have been observed at the end of extended oil drain intervals. A test method was established based on standard equipment already used for transmission fluid development. A modified FZG four-square test rig allows ageing a reduced oil volume to not decelerate development times. Applicability was demonstrated by ageing four full formulated transmission fluids using the new approach and comparing the results to aged transmission fluids sampled from durability testing. The oils aged with the FZG rig exhibit the same characteristics of scuffing load capacity degradation as observed in full transmission systems. However, in the full transmission system, the degradation starts at lower applied specific work, most likely due to the different system complexity. It is pointed out that not only the thermal load but also the tribological stresses have to be considered to mimic oil ageing.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"33 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136104812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-26DOI: 10.1177/13506501231209557
Wanglong Zhan, Yanfei Fang, Ping Huang
Dry friction problems are widespread in engineering applications. However, the current research on the contact pressure between interfaces mainly relies on static contact mechanics solutions, neglecting the influence of the contact pressure generated by the gases in the environment. In this paper, the ambient gas is considered as a lubricant with lubricating effects. Drawing inspiration from hydrodynamic lubrication methods, a unified mixed lubrication equation for dry friction problems is developed, taking into account the influence of gas rarefaction effects. This study computes the dry friction contact pressure under different winding speeds and loads. The advantage of this method lies in its ability to automatically distinguish between the contact and noncontact regions during the calculation process, enabling the determination of the contact pressure over the entire contact area. The computational results demonstrate that at low entrainment velocities, there is minimal deviation in contact pressure and contact area compared to Hertzian contact. However, as the entrainment velocity increases, the actual pressure-bearing area enlarges compared to static contact, and there is a smooth transition of pressure at the contact edge, which cannot be obtained from static contact analysis. Finally, the numerical solution of the contact pressure when the sliding speed spans several orders of magnitude is given, and the calculation results show that the numerical model has good robustness. This numerical approach offers valuable insights for guiding the design of air bearings in practical applications.
{"title":"Numerical solution of dry friction in point contact using the unified Reynolds method combined with rarefied gas effect","authors":"Wanglong Zhan, Yanfei Fang, Ping Huang","doi":"10.1177/13506501231209557","DOIUrl":"https://doi.org/10.1177/13506501231209557","url":null,"abstract":"Dry friction problems are widespread in engineering applications. However, the current research on the contact pressure between interfaces mainly relies on static contact mechanics solutions, neglecting the influence of the contact pressure generated by the gases in the environment. In this paper, the ambient gas is considered as a lubricant with lubricating effects. Drawing inspiration from hydrodynamic lubrication methods, a unified mixed lubrication equation for dry friction problems is developed, taking into account the influence of gas rarefaction effects. This study computes the dry friction contact pressure under different winding speeds and loads. The advantage of this method lies in its ability to automatically distinguish between the contact and noncontact regions during the calculation process, enabling the determination of the contact pressure over the entire contact area. The computational results demonstrate that at low entrainment velocities, there is minimal deviation in contact pressure and contact area compared to Hertzian contact. However, as the entrainment velocity increases, the actual pressure-bearing area enlarges compared to static contact, and there is a smooth transition of pressure at the contact edge, which cannot be obtained from static contact analysis. Finally, the numerical solution of the contact pressure when the sliding speed spans several orders of magnitude is given, and the calculation results show that the numerical model has good robustness. This numerical approach offers valuable insights for guiding the design of air bearings in practical applications.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"27 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135016604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-16DOI: 10.1177/13506501231206696
Lin Feng Qiao, Li Mo, Liangjie Mao, LingXiang Zeng
The John Crane 48 V mechanical seal is a long-distance oil transfer pump station shaft end seal; its sealing effect directly affects pipeline production safety. However, it has been found that there is oil leakage at the shaft end of the pump station. In order to explore the oil transfer pump mechanical seal abnormal leakage failure causes, to ensure the safety and stability of production, the end face of the 48 V mechanical seal was analyzed by white light interference and scanning electron microscope technology. The failure mechanism of the 48 V mechanical seal was explored from the perspective of the wear mechanism of moving and stationary rings. Results showed that the wear mechanism of the 48 V mechanical seal stationary ring was mainly abrasive wear, and substantial furrows, bulges, and depressions existed on the wear surface. The material removal mechanism was brittle spalling, and the roughness of the wear surface increased with the increase in wear depth and decreased with the increase in wear average width. Uneven wear occurred on the end face of the stationary ring of the mechanical seal, resulting in the leakage of the sealing medium from the end cover of the mechanical seal. The working condition could be improved by adding a spring compensation device to the stationary ring or increasing the gap between the stationary ring and the shaft sleeve.
{"title":"Wear mechanism and leakage failure analysis of the mechanical seal end face of an oil transfer pump","authors":"Lin Feng Qiao, Li Mo, Liangjie Mao, LingXiang Zeng","doi":"10.1177/13506501231206696","DOIUrl":"https://doi.org/10.1177/13506501231206696","url":null,"abstract":"The John Crane 48 V mechanical seal is a long-distance oil transfer pump station shaft end seal; its sealing effect directly affects pipeline production safety. However, it has been found that there is oil leakage at the shaft end of the pump station. In order to explore the oil transfer pump mechanical seal abnormal leakage failure causes, to ensure the safety and stability of production, the end face of the 48 V mechanical seal was analyzed by white light interference and scanning electron microscope technology. The failure mechanism of the 48 V mechanical seal was explored from the perspective of the wear mechanism of moving and stationary rings. Results showed that the wear mechanism of the 48 V mechanical seal stationary ring was mainly abrasive wear, and substantial furrows, bulges, and depressions existed on the wear surface. The material removal mechanism was brittle spalling, and the roughness of the wear surface increased with the increase in wear depth and decreased with the increase in wear average width. Uneven wear occurred on the end face of the stationary ring of the mechanical seal, resulting in the leakage of the sealing medium from the end cover of the mechanical seal. The working condition could be improved by adding a spring compensation device to the stationary ring or increasing the gap between the stationary ring and the shaft sleeve.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136078819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-12DOI: 10.1177/13506501231207162
Qi Zhao, Shaohang Yan, Mingchen Qiang, Yu Hou, Tianwei Lai
Under high-temperature conditions, heat evacuation of foil bearing has a significant impact on bearing performance, including loading performance and reliability. During bearing operation, viscous dissipative heat in the lubricant gas film is the main source of heat generation. For foil bearings, enhancing the heat evacuation efficiency is essential to extend the bearing service life in high-temperature environments. For heat evacuation, foil-side cooling is a very effective method. For more in-depth analysis of thermal characteristics of the foil bearing, a three-dimensional (3D) thermal-elasto-hydrodynamic (TEHD) coupling model of multi-leaf thrust foil bearing (MLTFB) with cooling channel is established in this paper. In view of the good heat transfer performance and more uniform gas velocity distribution in bionic flow channels, various bionic cooling channels of foil bearings are proposed and the structural parameters are optimized. The effects of cooling channel type, cooling channel width, span ratio, cooling gas supply mode, and rotational speed on the thermal and loading performance of foil bearings are investigated. The studies demonstrate that the spider net round cooling channel exhibits higher heat transfer performance and improved uniformity of temperature. Compared to the cooling gas supply from inner edge, the cooling gas supply from the outer edge proves to be more effective. The maximum temperature of lubricant gas film can be greatly reduced with wider cooling channels and a smaller channel span at the outer edge. The maximum temperature of lubricant gas film and bearing load are reduced as the Reynolds number of cooling gas increases. There exists an optimal Reynolds number that can achieve the highest uniformity of temperature.
{"title":"Thermal analysis and optimization of bionic cooling channels of gas foil thrust bearings","authors":"Qi Zhao, Shaohang Yan, Mingchen Qiang, Yu Hou, Tianwei Lai","doi":"10.1177/13506501231207162","DOIUrl":"https://doi.org/10.1177/13506501231207162","url":null,"abstract":"Under high-temperature conditions, heat evacuation of foil bearing has a significant impact on bearing performance, including loading performance and reliability. During bearing operation, viscous dissipative heat in the lubricant gas film is the main source of heat generation. For foil bearings, enhancing the heat evacuation efficiency is essential to extend the bearing service life in high-temperature environments. For heat evacuation, foil-side cooling is a very effective method. For more in-depth analysis of thermal characteristics of the foil bearing, a three-dimensional (3D) thermal-elasto-hydrodynamic (TEHD) coupling model of multi-leaf thrust foil bearing (MLTFB) with cooling channel is established in this paper. In view of the good heat transfer performance and more uniform gas velocity distribution in bionic flow channels, various bionic cooling channels of foil bearings are proposed and the structural parameters are optimized. The effects of cooling channel type, cooling channel width, span ratio, cooling gas supply mode, and rotational speed on the thermal and loading performance of foil bearings are investigated. The studies demonstrate that the spider net round cooling channel exhibits higher heat transfer performance and improved uniformity of temperature. Compared to the cooling gas supply from inner edge, the cooling gas supply from the outer edge proves to be more effective. The maximum temperature of lubricant gas film can be greatly reduced with wider cooling channels and a smaller channel span at the outer edge. The maximum temperature of lubricant gas film and bearing load are reduced as the Reynolds number of cooling gas increases. There exists an optimal Reynolds number that can achieve the highest uniformity of temperature.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135969126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-12DOI: 10.1177/13506501231204652
Guanglan Hu, Houfu Dai
The effect of the metal coating on the machinability of cubic silicon carbide was investigated by molecular dynamics simulation. The effect of the metal coating on the surface of the workpiece was explained using cutting force, friction coefficient, surface morphology, stress, temperature, and tool wear. The results show that the influence of metal type on cutting force, surface morphology, and stress is insignificant for coating thickness. However, the model with Cu coating has a tool suspension key number of 400 at the maximum cutting distance. The number of tool suspension keys for the Ni-Ti coating model is around 1700, indicating that the type of coating has a significant impact on tool wear. Furthermore, the results also show that in the three metals of Cu, Ni and Ni -Ti, Cu coating has the greatest impact on improving cutting performance. Among them, the average cutting force of 1.5 nm Cu coating is about 33.3% lower than that of without coating, and the tool wear is about 26.7% lower. These results demonstrate the effects of the metal coating on the workpiece surface from a theoretical point of view.
{"title":"Influence of the metal coating on nano-cutting process of cubic silicon carbide","authors":"Guanglan Hu, Houfu Dai","doi":"10.1177/13506501231204652","DOIUrl":"https://doi.org/10.1177/13506501231204652","url":null,"abstract":"The effect of the metal coating on the machinability of cubic silicon carbide was investigated by molecular dynamics simulation. The effect of the metal coating on the surface of the workpiece was explained using cutting force, friction coefficient, surface morphology, stress, temperature, and tool wear. The results show that the influence of metal type on cutting force, surface morphology, and stress is insignificant for coating thickness. However, the model with Cu coating has a tool suspension key number of 400 at the maximum cutting distance. The number of tool suspension keys for the Ni-Ti coating model is around 1700, indicating that the type of coating has a significant impact on tool wear. Furthermore, the results also show that in the three metals of Cu, Ni and Ni -Ti, Cu coating has the greatest impact on improving cutting performance. Among them, the average cutting force of 1.5 nm Cu coating is about 33.3% lower than that of without coating, and the tool wear is about 26.7% lower. These results demonstrate the effects of the metal coating on the workpiece surface from a theoretical point of view.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136014417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.1177/13506501231205172
R Ravivarman, R Prabhu Sekar
In this research, a finite-element model of internal gear drives with different tooth thickness factors (non-standard gear drives) is generated in order to investigate their performance characteristics. The finite-element analysis includes a focused mixture of non-standard internal gear set under enhanced bending and contact strength conditions for an accurate assessment of wear and efficiency. The analysis comprised gear sets having higher bending strength compared to the conditions in the standard internal gear drive to evaluate the tooth wear and its efficiency. A state-of-the-art semi-analytical nonlinear contact mechanics construction is executed to model a non-standard internal gear transmission unit. The tooth thickness of the non-standard internal gear is varied concerning the stresses and is quantified as a function. The computed results also extended with internal gear sets at varying operating parameters. The results evidently specify that power loss decreases with the proper combination of operating parameters. The results are presented and strategies concerning the design of a non-standard internal gear are also deliberated.
{"title":"An investigation of the wear and efficiency in non-standard internal spur gear set","authors":"R Ravivarman, R Prabhu Sekar","doi":"10.1177/13506501231205172","DOIUrl":"https://doi.org/10.1177/13506501231205172","url":null,"abstract":"In this research, a finite-element model of internal gear drives with different tooth thickness factors (non-standard gear drives) is generated in order to investigate their performance characteristics. The finite-element analysis includes a focused mixture of non-standard internal gear set under enhanced bending and contact strength conditions for an accurate assessment of wear and efficiency. The analysis comprised gear sets having higher bending strength compared to the conditions in the standard internal gear drive to evaluate the tooth wear and its efficiency. A state-of-the-art semi-analytical nonlinear contact mechanics construction is executed to model a non-standard internal gear transmission unit. The tooth thickness of the non-standard internal gear is varied concerning the stresses and is quantified as a function. The computed results also extended with internal gear sets at varying operating parameters. The results evidently specify that power loss decreases with the proper combination of operating parameters. The results are presented and strategies concerning the design of a non-standard internal gear are also deliberated.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135345724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-06DOI: 10.1177/13506501231205361
Xiang Wang, Wanjun Xu
The Elrod algorithm is widely used for the study of bearing cavitation problems. However, the potential instability of the algorithm makes it difficult to use in practical applications. A simplified Elrod algorithm based on a decoupled technique was developed. The new algorithm is well-regularized because the tough switch function used for the shear flow term is removed. The most significant advantage of the algorithm is the stability, unlike the traditional algorithm where the accuracy of results irregularly depends on the choice of grids. The numerical experiments, including a journal bearing and a surface-dimpled thrust bearing, show that the simplified Elrod algorithm converges consistently for all cases studied, while the traditional Elrod algorithm fails to converge for cases with a special number of grids. The simplified Elrod algorithm is considered to be a robust alternative to the traditional Elrod algorithm.
{"title":"A decoupled approach to enhance the Elrod algorithm","authors":"Xiang Wang, Wanjun Xu","doi":"10.1177/13506501231205361","DOIUrl":"https://doi.org/10.1177/13506501231205361","url":null,"abstract":"The Elrod algorithm is widely used for the study of bearing cavitation problems. However, the potential instability of the algorithm makes it difficult to use in practical applications. A simplified Elrod algorithm based on a decoupled technique was developed. The new algorithm is well-regularized because the tough switch function used for the shear flow term is removed. The most significant advantage of the algorithm is the stability, unlike the traditional algorithm where the accuracy of results irregularly depends on the choice of grids. The numerical experiments, including a journal bearing and a surface-dimpled thrust bearing, show that the simplified Elrod algorithm converges consistently for all cases studied, while the traditional Elrod algorithm fails to converge for cases with a special number of grids. The simplified Elrod algorithm is considered to be a robust alternative to the traditional Elrod algorithm.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135352628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}