Abstract
Since emulsions combine good lubricating and cooling capabilities, they have been widely used in metal rolling and cutting. This study first uses AR2000 rheometer to measure viscosity of emulsions under atmospheric pressure. The results of the test show that the viscosity of emulsions is approximately the highest in the 80% oil volume fraction. Meanwhile, the viscosity drops along with increasing the shear rate, it proves that emulsions are a pseudoplastic fluid.
This study uses an EHL squeeze tester to explore the effects of squeeze velocity, load and volume fraction concentration of oil phase of emulsions on the dimple film thickness in the contact conjunction of squeezing lubrication. Results show that the dimple becomes deeper with increasing squeeze velocity. When the load increases, the dimple can keep longer due to higher hertz pressure. Furthermore, emulsions which have the higher oil volume fraction, have the higher maximum dimple depth under the same load and squeeze velocity. The results are different that the viscosity of 80% emulsions is higher than crude oil under atmospheric pressure. It is because that the significantly effect of pressure on the viscosity of oil phase, and the surface viscosity between oil and water phases can be ignored.
Keywords: emulsions, EHL, dimple
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0908108-132805 |
| Date | 08 September 2008 |
| Creators | Chen, Yen-an |
| Contributors | Chang, Yuh-Ping, Chiou, Yuang-Cherng, Chu, Li-Ming, Lee, Rong-Tsong |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0908108-132805 |
| Rights | campus_withheld, Copyright information available at source archive |
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