Tribological Stress of Lubricating Greases in the Light of System Entropy
Lubricating greases show a structural degradation due to friction stress. The shear process dissipates energy. This results in a breakdown of the thickener structure, heat and entropy generation. Tribo-systems are energy driven systems. The stressed lubricating grease is modeled as a subsystem and p...
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| Format: | Article |
| Language: | English |
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MDPI AG
2016-11-01
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| Series: | Lubricants |
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| Online Access: | http://www.mdpi.com/2075-4442/4/4/37 |
| _version_ | 1811263302819381248 |
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| author | Erik Kuhn |
| author_facet | Erik Kuhn |
| author_sort | Erik Kuhn |
| collection | DOAJ |
| description | Lubricating greases show a structural degradation due to friction stress. The shear process dissipates energy. This results in a breakdown of the thickener structure, heat and entropy generation. Tribo-systems are energy driven systems. The stressed lubricating grease is modeled as a subsystem and presents an open thermodynamic system. Investigations were made to obtain more information about the correlation of system entropy and structural degradation of a lubricating grease. Experimental studies were done to estimate the role in terms of entropy transport for the open system. The degradation-entropy theorem was applied with the help of an empirical model to describe the correlation between degradation process and entropy production for the special case of a closed and stationary system. |
| first_indexed | 2024-04-12T19:42:19Z |
| format | Article |
| id | doaj.art-70f5d795a1df4cc08b5000f0b57188e8 |
| institution | Directory Open Access Journal |
| issn | 2075-4442 |
| language | English |
| last_indexed | 2024-04-12T19:42:19Z |
| publishDate | 2016-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Lubricants |
| spelling | doaj.art-70f5d795a1df4cc08b5000f0b57188e82022-12-22T03:19:03ZengMDPI AGLubricants2075-44422016-11-01443710.3390/lubricants4040037lubricants4040037Tribological Stress of Lubricating Greases in the Light of System EntropyErik Kuhn0Laboratory of Machine Elements and Tribology (MuT), Institute of Engineering Design and Product Development, Hamburg University of Applied Sciences, 20099 Hamburg, GermanyLubricating greases show a structural degradation due to friction stress. The shear process dissipates energy. This results in a breakdown of the thickener structure, heat and entropy generation. Tribo-systems are energy driven systems. The stressed lubricating grease is modeled as a subsystem and presents an open thermodynamic system. Investigations were made to obtain more information about the correlation of system entropy and structural degradation of a lubricating grease. Experimental studies were done to estimate the role in terms of entropy transport for the open system. The degradation-entropy theorem was applied with the help of an empirical model to describe the correlation between degradation process and entropy production for the special case of a closed and stationary system.http://www.mdpi.com/2075-4442/4/4/37lubricating greasestructural degradationentropy |
| spellingShingle | Erik Kuhn Tribological Stress of Lubricating Greases in the Light of System Entropy Lubricants lubricating grease structural degradation entropy |
| title | Tribological Stress of Lubricating Greases in the Light of System Entropy |
| title_full | Tribological Stress of Lubricating Greases in the Light of System Entropy |
| title_fullStr | Tribological Stress of Lubricating Greases in the Light of System Entropy |
| title_full_unstemmed | Tribological Stress of Lubricating Greases in the Light of System Entropy |
| title_short | Tribological Stress of Lubricating Greases in the Light of System Entropy |
| title_sort | tribological stress of lubricating greases in the light of system entropy |
| topic | lubricating grease structural degradation entropy |
| url | http://www.mdpi.com/2075-4442/4/4/37 |
| work_keys_str_mv | AT erikkuhn tribologicalstressoflubricatinggreasesinthelightofsystementropy |