Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading
Consideration of performance, efficiency and energy consumption is nowadays an inherent part of the design of every modern machine. These factors are mainly determined by mechanisms taking place within the lubricated contacts. Unfortunately, the physical origins of these mechanisms have been investi...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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University of Kragujevac
2017-12-01
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| Series: | Tribology in Industry |
| Subjects: | |
| Online Access: | http://www.tribology.fink.rs/journals/2017/2017-4/2017-4-10.html |
| _version_ | 1818128768305201152 |
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| author | J. Fryza P. Sperka I. Krupka M. Hartl |
| author_facet | J. Fryza P. Sperka I. Krupka M. Hartl |
| author_sort | J. Fryza |
| collection | DOAJ |
| description | Consideration of performance, efficiency and energy consumption is nowadays an inherent part of the design of every modern machine. These factors are mainly determined by mechanisms taking place within the lubricated contacts. Unfortunately, the physical origins of these mechanisms have been investigated exclusively for steady conditions that do not occur in actual contacts of machines affected by vibrations. This study presents novel experimental data describing friction in the elastohydrodynamically lubricated contact exposed to the main steady sliding motion along with lateral sliding micro-oscillations. Friction forces were measured simultaneously in two perpendicular directions of point contact. It is shown that the lubricant response in the main direction of motion suffers from shear thinning and thermal effects whereas its lateral response is isothermal Newtonian. Moreover, the lateral friction affects the friction in the main direction, but not vice versa, when the majority of shear flow is maintained in this main direction. These finding are attributed to the perturbation of structural arrangement of lubricant. The results also suggest that a response of mineral oils to shearing is anisotropic. A limiting shear stress is discussed since the total friction was not able to exceed a certain value. |
| first_indexed | 2024-12-11T07:38:30Z |
| format | Article |
| id | doaj.art-66b1601f105f451c8d33c7689aa62e6d |
| institution | Directory Open Access Journal |
| issn | 0354-8996 2217-7965 |
| language | English |
| last_indexed | 2024-12-11T07:38:30Z |
| publishDate | 2017-12-01 |
| publisher | University of Kragujevac |
| record_format | Article |
| series | Tribology in Industry |
| spelling | doaj.art-66b1601f105f451c8d33c7689aa62e6d2022-12-22T01:15:39ZengUniversity of KragujevacTribology in Industry0354-89962217-79652017-12-01394506518Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear LoadingJ. Fryza0P. Sperka1I. Krupka2M. Hartl3Brno University of Technology, Technicka 2896/2 Brno, Czech RepublicBrno University of Technology, Technicka 2896/2 Brno, Czech RepublicBrno University of Technology, Technicka 2896/2 Brno, Czech RepublicBrno University of Technology, Technicka 2896/2 Brno, Czech RepublicConsideration of performance, efficiency and energy consumption is nowadays an inherent part of the design of every modern machine. These factors are mainly determined by mechanisms taking place within the lubricated contacts. Unfortunately, the physical origins of these mechanisms have been investigated exclusively for steady conditions that do not occur in actual contacts of machines affected by vibrations. This study presents novel experimental data describing friction in the elastohydrodynamically lubricated contact exposed to the main steady sliding motion along with lateral sliding micro-oscillations. Friction forces were measured simultaneously in two perpendicular directions of point contact. It is shown that the lubricant response in the main direction of motion suffers from shear thinning and thermal effects whereas its lateral response is isothermal Newtonian. Moreover, the lateral friction affects the friction in the main direction, but not vice versa, when the majority of shear flow is maintained in this main direction. These finding are attributed to the perturbation of structural arrangement of lubricant. The results also suggest that a response of mineral oils to shearing is anisotropic. A limiting shear stress is discussed since the total friction was not able to exceed a certain value.http://www.tribology.fink.rs/journals/2017/2017-4/2017-4-10.htmlElastohydrodynamic lubricationFrictionShear flowNon-steady stateLimiting shear stress |
| spellingShingle | J. Fryza P. Sperka I. Krupka M. Hartl Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading Tribology in Industry Elastohydrodynamic lubrication Friction Shear flow Non-steady state Limiting shear stress |
| title | Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading |
| title_full | Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading |
| title_fullStr | Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading |
| title_full_unstemmed | Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading |
| title_short | Frictional Response of Lubricant in EHL Contact under Transient Bi-directional Shear Loading |
| title_sort | frictional response of lubricant in ehl contact under transient bi directional shear loading |
| topic | Elastohydrodynamic lubrication Friction Shear flow Non-steady state Limiting shear stress |
| url | http://www.tribology.fink.rs/journals/2017/2017-4/2017-4-10.html |
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