Pub Date : 2023-07-10DOI: 10.1177/13506501231187316
Chunjie Wei, Guiwen Liao, Wen Wang, Jimin Xu, Kun Liu
The transient tribo-dynamics and wear model are coupled to study the mixed lubrication-wear behavior during start-up. The coupled numerical model involves the film thickness equation with wear depth and a time-varying wear coefficient to account for the impact of transient mixed lubrication behavior on wear. In this study, the evolution of wear and mixed lubrication performance distribution over time is predicted, and the impact of acceleration mode, acceleration time, external load, lubricant viscosity, and start-up time on the numerical predictions is evaluated. The findings demonstrate that wear behavior, particularly in the analysis of the effects of acceleration mode and acceleration time, has a significant impact on the evaluation of the bearing-rotor system's start-up performance and even changes the determination of optimal parameters. Furthermore, the parametric study demonstrates that wear and mixed lubrication performance are sensitive to the external load and lubricant viscosity. Finally, studies on the effect of start-up times show that proper wear geometry promotes hydrodynamic effects, but severely worn bearing surfaces have a negative effect on start-up.
{"title":"Transient tribo-dynamic performance of journal bearings considering wear behavior during start-up","authors":"Chunjie Wei, Guiwen Liao, Wen Wang, Jimin Xu, Kun Liu","doi":"10.1177/13506501231187316","DOIUrl":"https://doi.org/10.1177/13506501231187316","url":null,"abstract":"The transient tribo-dynamics and wear model are coupled to study the mixed lubrication-wear behavior during start-up. The coupled numerical model involves the film thickness equation with wear depth and a time-varying wear coefficient to account for the impact of transient mixed lubrication behavior on wear. In this study, the evolution of wear and mixed lubrication performance distribution over time is predicted, and the impact of acceleration mode, acceleration time, external load, lubricant viscosity, and start-up time on the numerical predictions is evaluated. The findings demonstrate that wear behavior, particularly in the analysis of the effects of acceleration mode and acceleration time, has a significant impact on the evaluation of the bearing-rotor system's start-up performance and even changes the determination of optimal parameters. Furthermore, the parametric study demonstrates that wear and mixed lubrication performance are sensitive to the external load and lubricant viscosity. Finally, studies on the effect of start-up times show that proper wear geometry promotes hydrodynamic effects, but severely worn bearing surfaces have a negative effect on start-up.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"106 1","pages":"1809 - 1825"},"PeriodicalIF":2.0,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90900469","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 : 2023-07-10DOI: 10.1177/13506501231184304
A. Borgaonkar, I. Syed
Machining is one of the basic and inevitable operations in the manufacturing industry. The machining performance is estimated based on various parameters like cutting forces, surface roughness, tool–chip interface temperature, and specific energy. In the traditional approach, cutting fluids are greatly utilized to dissipate the generated heat during machining, but their utilization causes a threat to nature and human being’s health. Therefore, there emerges a necessity to determine user-friendly, sustainable, and eco-friendly substitutes for traditional cutting fluids. The field of advanced tribology has proposed the usage of solid lubricants due to their inherent properties, such as excellent tribological performance, reduced machining zone temperature due to lowered friction, and enhanced tool life. Therefore, in the present study, pure MoS2 and composite MoS2–TiO2 solid lubricants have been employed in the milling process of AISI 52100 steel with HSS end mill cutter. The machining was carried out in different conditions such as uncoated tool without use of lubricant, uncoated tool with use of lubricant, coated tool without use of lubricant, and coated tool with use of lubricant that were employed to analyze their effect on machining performance. The experimental results showed substantial improvement regarding reduced cutting forces, reduced temperature at tool–chip interface, improved surface finish, and average tool wear with the application of solid lubricants. Among the various lubricating conditions, composite MoS2–TiO2-coated tool with composite MoS2–TiO2 lubricant exhibits excellent machining performance.
{"title":"Eco-friendly sustainable machining with MoS2-based solid lubricant","authors":"A. Borgaonkar, I. Syed","doi":"10.1177/13506501231184304","DOIUrl":"https://doi.org/10.1177/13506501231184304","url":null,"abstract":"Machining is one of the basic and inevitable operations in the manufacturing industry. The machining performance is estimated based on various parameters like cutting forces, surface roughness, tool–chip interface temperature, and specific energy. In the traditional approach, cutting fluids are greatly utilized to dissipate the generated heat during machining, but their utilization causes a threat to nature and human being’s health. Therefore, there emerges a necessity to determine user-friendly, sustainable, and eco-friendly substitutes for traditional cutting fluids. The field of advanced tribology has proposed the usage of solid lubricants due to their inherent properties, such as excellent tribological performance, reduced machining zone temperature due to lowered friction, and enhanced tool life. Therefore, in the present study, pure MoS2 and composite MoS2–TiO2 solid lubricants have been employed in the milling process of AISI 52100 steel with HSS end mill cutter. The machining was carried out in different conditions such as uncoated tool without use of lubricant, uncoated tool with use of lubricant, coated tool without use of lubricant, and coated tool with use of lubricant that were employed to analyze their effect on machining performance. The experimental results showed substantial improvement regarding reduced cutting forces, reduced temperature at tool–chip interface, improved surface finish, and average tool wear with the application of solid lubricants. Among the various lubricating conditions, composite MoS2–TiO2-coated tool with composite MoS2–TiO2 lubricant exhibits excellent machining performance.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"69 1","pages":"1783 - 1795"},"PeriodicalIF":2.0,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82342158","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 : 2023-07-04DOI: 10.1177/13506501231183860
J. Snieder, M. Dielen, R. V. van Ostayen
This work presents the development of a numerical model for the elastohydrodynamic lubrication of roll-to-plate nanoimprinting with flexible stamps. Roll-to-plate nanoimprinting is a manufacturing method to replicate micro- and nanotextures on large-area substrates with ultraviolet-curable resins. The roller is equipped with a relatively soft elastomeric layer, which elastically deforms during the imprint process. The elastic deformation is described by linear elasticity theory. It is coupled to the pressure build-up in the liquid resin film, which is described by lubrication theory. The flexible stamp, which is treated as a tensioned web, is pre-tensioned around the roller. The elastic deformation of the tensioned web is described by the large-deflection bending of thin plates equations, considering its non-negligible bending stiffness. A Fischer–Burmeister complementarity condition captures the contact mechanics between the tensioned web and the roller. The governing equations combine in a coupled elastohydrodynamic lubrication model, which is fully described by a set of non-dimensional numbers. These are used in a parameter study to investigate the effect on the pressure and film height distributions. It is shown that the bending stiffness of the tensioned web results in an additional hydrodynamic pressure peak and corresponding minimum in the film height, near the inlet of the roller contact. An increase of the bending stiffness corresponds to a decrease in film height. The numerical results are compared with benchmarks from literature and experimentally validated with layer height measurements from flat layer imprints. Good agreement is found between the numerical and experimental results.
{"title":"Elastohydrodynamic lubrication of soft-layered rollers and tensioned webs in roll-to-plate nanoimprinting","authors":"J. Snieder, M. Dielen, R. V. van Ostayen","doi":"10.1177/13506501231183860","DOIUrl":"https://doi.org/10.1177/13506501231183860","url":null,"abstract":"This work presents the development of a numerical model for the elastohydrodynamic lubrication of roll-to-plate nanoimprinting with flexible stamps. Roll-to-plate nanoimprinting is a manufacturing method to replicate micro- and nanotextures on large-area substrates with ultraviolet-curable resins. The roller is equipped with a relatively soft elastomeric layer, which elastically deforms during the imprint process. The elastic deformation is described by linear elasticity theory. It is coupled to the pressure build-up in the liquid resin film, which is described by lubrication theory. The flexible stamp, which is treated as a tensioned web, is pre-tensioned around the roller. The elastic deformation of the tensioned web is described by the large-deflection bending of thin plates equations, considering its non-negligible bending stiffness. A Fischer–Burmeister complementarity condition captures the contact mechanics between the tensioned web and the roller. The governing equations combine in a coupled elastohydrodynamic lubrication model, which is fully described by a set of non-dimensional numbers. These are used in a parameter study to investigate the effect on the pressure and film height distributions. It is shown that the bending stiffness of the tensioned web results in an additional hydrodynamic pressure peak and corresponding minimum in the film height, near the inlet of the roller contact. An increase of the bending stiffness corresponds to a decrease in film height. The numerical results are compared with benchmarks from literature and experimentally validated with layer height measurements from flat layer imprints. Good agreement is found between the numerical and experimental results.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"4 1","pages":"1871 - 1884"},"PeriodicalIF":2.0,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76207728","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 : 2023-07-02DOI: 10.1177/13506501231184736
Songjie Yue, K. Cheng, Qing-Xi Bai, H. Ding
Aerostatic spindles are commonly employed in ultra-precision machines. The aerostatic spindle, as a critical key component for the development of industrial ultra-precision grinding machines, requires an industrial feasible precision engineering approach to robust design and optimization in order to render the high-precision spindle system. This paper presents such an approach to the design and development of aerostatic spindles and the associated digital virtual spindle systems based on multiscale modelling and analysis. Multiscale modelling and analysis combined with the virtual spindle simulation are used as the kernel of the virtual spindle system, including innovative design on the spindle system structure, fluid dynamics modelling, drive and control system, and the integration of the spindle electromechanical system, which can be used to systematically model and simulate both the static and dynamic performances of the aerostatic spindle system. Experiments are carried out to evaluate and validate the above approach and the virtual spindle simulations, which can be further utilized for the development of next-generation high-precision aerostatic spindle systems.
{"title":"Integrated design and analysis of a high-precision aerostatic spindle for internal grinding machines and its implementation perspectives","authors":"Songjie Yue, K. Cheng, Qing-Xi Bai, H. Ding","doi":"10.1177/13506501231184736","DOIUrl":"https://doi.org/10.1177/13506501231184736","url":null,"abstract":"Aerostatic spindles are commonly employed in ultra-precision machines. The aerostatic spindle, as a critical key component for the development of industrial ultra-precision grinding machines, requires an industrial feasible precision engineering approach to robust design and optimization in order to render the high-precision spindle system. This paper presents such an approach to the design and development of aerostatic spindles and the associated digital virtual spindle systems based on multiscale modelling and analysis. Multiscale modelling and analysis combined with the virtual spindle simulation are used as the kernel of the virtual spindle system, including innovative design on the spindle system structure, fluid dynamics modelling, drive and control system, and the integration of the spindle electromechanical system, which can be used to systematically model and simulate both the static and dynamic performances of the aerostatic spindle system. Experiments are carried out to evaluate and validate the above approach and the virtual spindle simulations, which can be further utilized for the development of next-generation high-precision aerostatic spindle systems.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2023-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87425741","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 : 2023-06-13DOI: 10.1177/13506501231181271
Fuyu Liu, Bo Yu, Yongfan Li, Baojie Ren, Muming Hao, Xinhui Sun, Zengli Wang, Zhentao Li
This research investigated the effect of lubricant's non-Newtonian properties on dynamic characteristics of a herringbone grooved liquid film seal (HG-LFS) considering cavitation. A modified steady-state perturbation Reynolds equation of the non-Newtonian was derived. Visualized experiments were conducted to verify the accuracy of calculations. The non-Newtonian effect on stiffness, cavitation, damping coefficients, and other sealing performance of the liquid film seal at different velocity, pressure and film thickness were discussed and analyzed. The results indicate that the seal has larger stiffness and damping coefficients with the dilatant lubricant, the cavitation can be inhibited by the shearing-thinning lubricant, and the impact of non-Newtonian on the seal stability decreases with the increase of film thickness. This study would contribute to the design and theoretical research of liquid film seals.
{"title":"Dynamic characteristics of a non-Newtonian lubrication mechanical seal with herringbone grooves considering cavitation effect","authors":"Fuyu Liu, Bo Yu, Yongfan Li, Baojie Ren, Muming Hao, Xinhui Sun, Zengli Wang, Zhentao Li","doi":"10.1177/13506501231181271","DOIUrl":"https://doi.org/10.1177/13506501231181271","url":null,"abstract":"This research investigated the effect of lubricant's non-Newtonian properties on dynamic characteristics of a herringbone grooved liquid film seal (HG-LFS) considering cavitation. A modified steady-state perturbation Reynolds equation of the non-Newtonian was derived. Visualized experiments were conducted to verify the accuracy of calculations. The non-Newtonian effect on stiffness, cavitation, damping coefficients, and other sealing performance of the liquid film seal at different velocity, pressure and film thickness were discussed and analyzed. The results indicate that the seal has larger stiffness and damping coefficients with the dilatant lubricant, the cavitation can be inhibited by the shearing-thinning lubricant, and the impact of non-Newtonian on the seal stability decreases with the increase of film thickness. This study would contribute to the design and theoretical research of liquid film seals.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"59 1","pages":"1768 - 1782"},"PeriodicalIF":2.0,"publicationDate":"2023-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73512344","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 present study, the effect of surface waviness on the performance of journal bearing operating in misaligned conditions has been investigated. The journal’s misaligned conditions in the present analysis are taken about the circumferential, the axial, and both axes. For computing the pressure of lubricant inside the bearing, the finite element method has been applied to solve the Reynolds equation and thus static parameters are obtained. The static parameters, that is, load carrying capacity and coefficient of friction are evaluated at different waviness variables and are compared with misaligned journal bearing without surface waviness. It is observed that misalignment considered in both axes has the most severe effect on static performance parameters as compared to misalignment only in the circumferential or axial axis. With the increase in circumferential waviness number up to n = 5, the load-carrying capacity increases, and the coefficient of friction decreases under high eccentricity ratios. Change in waviness amplitude also impacts the bearing performance. Axial waviness always deteriorates the bearing performance. Combined waviness increases the load carrying capacity and decreases the coefficient of friction when circumferential waviness number n = 5 and axial waviness number m = 2. The highest performance enhancement ratio is attained at an eccentricity ratio of 0.8 with a circumferential waviness number n of 5, axial waviness number m of 2, and dimensionless waviness amplitude δ * of 0.075.
{"title":"Performance analysis of journal bearing having surface waviness operating under misaligned condition","authors":"Arun Bangotra, Sanjay Sharma, Reza Taufique, Deepak Byotra","doi":"10.1177/13506501231177485","DOIUrl":"https://doi.org/10.1177/13506501231177485","url":null,"abstract":"In this present study, the effect of surface waviness on the performance of journal bearing operating in misaligned conditions has been investigated. The journal’s misaligned conditions in the present analysis are taken about the circumferential, the axial, and both axes. For computing the pressure of lubricant inside the bearing, the finite element method has been applied to solve the Reynolds equation and thus static parameters are obtained. The static parameters, that is, load carrying capacity and coefficient of friction are evaluated at different waviness variables and are compared with misaligned journal bearing without surface waviness. It is observed that misalignment considered in both axes has the most severe effect on static performance parameters as compared to misalignment only in the circumferential or axial axis. With the increase in circumferential waviness number up to n = 5, the load-carrying capacity increases, and the coefficient of friction decreases under high eccentricity ratios. Change in waviness amplitude also impacts the bearing performance. Axial waviness always deteriorates the bearing performance. Combined waviness increases the load carrying capacity and decreases the coefficient of friction when circumferential waviness number n = 5 and axial waviness number m = 2. The highest performance enhancement ratio is attained at an eccentricity ratio of 0.8 with a circumferential waviness number n of 5, axial waviness number m of 2, and dimensionless waviness amplitude δ * of 0.075.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"5 1","pages":"1657 - 1669"},"PeriodicalIF":2.0,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85991785","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 : 2023-06-06DOI: 10.1177/13506501231179526
B. Manser, S. Khelladi, M. Deligant, H. Ragueb, I. Belaidi, F. Bakir
This study outlines the performances of finite-length journal bearing with textured liner, shear-thinning Rabinowitsch lubricants, and considers the elastic deformation of the bearing liner. The yielded nonlinear Rabinowitsch-Reynolds PDE system has been solved using the finite difference method combined with Elrod’s algorithm for the case of cylindrical textures. The static performance of hydrodynamic lubrication, in this case, involves different parameters such as depth of texture, eccentricity ratio, elastic deformation factor, rheological index, etc. Results showed that, at a fixed eccentricity ratio, texturing of the bearing’s converging area enhances significantly the load-carrying capacity and reduces the friction coefficient compared to the smooth bearing surface (up to 22 % in load capacity and 17 % in friction coefficient). On the other hand, using a lubricant with more pronounced shear-thinning behavior and/or elastic liner reduces the journal bearing performances (up to 25 % in load capacity and 30 % in pressure). By applying the optimization technique (particle swarm optimization), an optimal arrangement of textures that can compensate for these losses in performance even at high eccentricity has been found. This optimal texture with dimensionless dimple’s depth set to 1 ( r y = 40 μ m ) improves the load capacity with 10 % for a lubricant with a rheological index α ¯ = 0.6 and elastic bearing liner with deformation parameter C 0 = 0.05 .
{"title":"Performance of hydrodynamic textured journal bearing with the combined influence of elastic deformation and pseudo-plastic lubricant","authors":"B. Manser, S. Khelladi, M. Deligant, H. Ragueb, I. Belaidi, F. Bakir","doi":"10.1177/13506501231179526","DOIUrl":"https://doi.org/10.1177/13506501231179526","url":null,"abstract":"This study outlines the performances of finite-length journal bearing with textured liner, shear-thinning Rabinowitsch lubricants, and considers the elastic deformation of the bearing liner. The yielded nonlinear Rabinowitsch-Reynolds PDE system has been solved using the finite difference method combined with Elrod’s algorithm for the case of cylindrical textures. The static performance of hydrodynamic lubrication, in this case, involves different parameters such as depth of texture, eccentricity ratio, elastic deformation factor, rheological index, etc. Results showed that, at a fixed eccentricity ratio, texturing of the bearing’s converging area enhances significantly the load-carrying capacity and reduces the friction coefficient compared to the smooth bearing surface (up to 22 % in load capacity and 17 % in friction coefficient). On the other hand, using a lubricant with more pronounced shear-thinning behavior and/or elastic liner reduces the journal bearing performances (up to 25 % in load capacity and 30 % in pressure). By applying the optimization technique (particle swarm optimization), an optimal arrangement of textures that can compensate for these losses in performance even at high eccentricity has been found. This optimal texture with dimensionless dimple’s depth set to 1 ( r y = 40 μ m ) improves the load capacity with 10 % for a lubricant with a rheological index α ¯ = 0.6 and elastic bearing liner with deformation parameter C 0 = 0.05 .","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"150 1","pages":"1885 - 1912"},"PeriodicalIF":2.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77437885","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 : 2023-06-06DOI: 10.1177/13506501231177484
P. Dellis
The lubricated interface at the piston-ring and liner and its interaction with different lubricants and testing conditions is examined in terms of experimental measurements that show the minimum oil film thickness developed at the lubricated or depending on conditions partly lubricated conjunction and the surface interaction intensity, as measured from the friction sensor. An analysis is carried out with the use of different parameters for the experiments as well as different lubricants in a simplified piston-ring simulation test rig. This analysis is further enhanced with the squeeze film effect investigations close to the stroke reversals and together with cavitation initiation and load-carrying effect results from previous experimental data, light is shed on the interacting surface’s behaviour at the different lubrication regimes. Another parameter, the viscosity index of the lubricant is used as an indication of the effects of squeeze film shift and friction force measurements and how the load and temperature effect are influencing the squeeze film.
{"title":"On the effect of temperature in friction force measurements for a simplified piston cylinder set-up: Squeeze film combined with minimum oil film thickness measurements and viscosity index effect","authors":"P. Dellis","doi":"10.1177/13506501231177484","DOIUrl":"https://doi.org/10.1177/13506501231177484","url":null,"abstract":"The lubricated interface at the piston-ring and liner and its interaction with different lubricants and testing conditions is examined in terms of experimental measurements that show the minimum oil film thickness developed at the lubricated or depending on conditions partly lubricated conjunction and the surface interaction intensity, as measured from the friction sensor. An analysis is carried out with the use of different parameters for the experiments as well as different lubricants in a simplified piston-ring simulation test rig. This analysis is further enhanced with the squeeze film effect investigations close to the stroke reversals and together with cavitation initiation and load-carrying effect results from previous experimental data, light is shed on the interacting surface’s behaviour at the different lubrication regimes. Another parameter, the viscosity index of the lubricant is used as an indication of the effects of squeeze film shift and friction force measurements and how the load and temperature effect are influencing the squeeze film.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"15 1","pages":"1723 - 1742"},"PeriodicalIF":2.0,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79198266","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 : 2023-06-02DOI: 10.1177/13506501231179851
Bin Wei, Y. Jiao
This work aims to study the effect of semi-ellipsoid texture on the bearing load capacity and maximum oil film temperature of tilting pad journal bearings. It has been shown that surface texture can improve the steady-state performance of bearings, but there are few studies on tilting pad journal bearings. A thermal elastohydrodynamic model of tilting pad journal bearings have been developed to support the analysis and solved by the finite difference method. The calculation results of the model are in good agreement with the simulation results of MADYN 2000 software, which proves the validity of the model. The effects of texture distribution, depth, radius, and density on the characteristics of tilting pad journal bearings were studied and compared with those of untextured tilting pad journal bearings. The results show that texture can significantly enhance or weaken the steady-state characteristics of tilting pad journal bearings, which is related to the texture parameters. This work provides a reference for the design of tilting pad journal bearings.
{"title":"Numerical analysis of the effect of texture on the steady-state characteristics of tilting pad journal bearings","authors":"Bin Wei, Y. Jiao","doi":"10.1177/13506501231179851","DOIUrl":"https://doi.org/10.1177/13506501231179851","url":null,"abstract":"This work aims to study the effect of semi-ellipsoid texture on the bearing load capacity and maximum oil film temperature of tilting pad journal bearings. It has been shown that surface texture can improve the steady-state performance of bearings, but there are few studies on tilting pad journal bearings. A thermal elastohydrodynamic model of tilting pad journal bearings have been developed to support the analysis and solved by the finite difference method. The calculation results of the model are in good agreement with the simulation results of MADYN 2000 software, which proves the validity of the model. The effects of texture distribution, depth, radius, and density on the characteristics of tilting pad journal bearings were studied and compared with those of untextured tilting pad journal bearings. The results show that texture can significantly enhance or weaken the steady-state characteristics of tilting pad journal bearings, which is related to the texture parameters. This work provides a reference for the design of tilting pad journal bearings.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"16 1","pages":"1743 - 1756"},"PeriodicalIF":2.0,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87004468","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 : 2023-05-31DOI: 10.1177/13506501231179776
G. Kumar, H. Garg
Growing environment concern has forced us for the development of environmentally acceptable lubricants. In this study, tribological properties of sesame oil and castor oil containing imidazolium-based ionic liquid 1-ethyl 3methylimidazolium dicyanamide ([EMIM][DCN]) (IL1), phosphonium-based ionic liquid Trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ([P66614][BTMPP]) (IL2) and titanium oxide (TiO2) nanoparticles (NPs) as hybrid additives have been investigated using four-ball tester with ASTM D4172B. Three different concentrations of IL1, IL2 and TiO2 NPs were selected for the formulation of vegetable oil–based ionanolubricants. It was found that castor oil with the addition of 0.03 ∅ of TiO2 NPs and 1.3 vol.% of IL1 shows the lowest specific wear rate amongst all investigated lubricant samples. It is evident from field emission scanning electron microscopy analysis of worn-out surfaces of steel balls that a combination of ball bearing effect and tribofilm formation is responsible for the improved tribological characteristics.
{"title":"Evaluation of tribological properties of vegetable oil–based ionanolubricants: An experimental study","authors":"G. Kumar, H. Garg","doi":"10.1177/13506501231179776","DOIUrl":"https://doi.org/10.1177/13506501231179776","url":null,"abstract":"Growing environment concern has forced us for the development of environmentally acceptable lubricants. In this study, tribological properties of sesame oil and castor oil containing imidazolium-based ionic liquid 1-ethyl 3methylimidazolium dicyanamide ([EMIM][DCN]) (IL1), phosphonium-based ionic liquid Trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ([P66614][BTMPP]) (IL2) and titanium oxide (TiO2) nanoparticles (NPs) as hybrid additives have been investigated using four-ball tester with ASTM D4172B. Three different concentrations of IL1, IL2 and TiO2 NPs were selected for the formulation of vegetable oil–based ionanolubricants. It was found that castor oil with the addition of 0.03 ∅ of TiO2 NPs and 1.3 vol.% of IL1 shows the lowest specific wear rate amongst all investigated lubricant samples. It is evident from field emission scanning electron microscopy analysis of worn-out surfaces of steel balls that a combination of ball bearing effect and tribofilm formation is responsible for the improved tribological characteristics.","PeriodicalId":20570,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology","volume":"70 1","pages":"1757 - 1767"},"PeriodicalIF":2.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73876591","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}