한국윤활학회:학술대회논문집 (Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference)
- 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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- Pages.85-86
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- 2002
Estimation of the Lubricating Oil Rheology at High Pressure Based on Phase Diagram
초록
For rheology investigation of lubricating oils, first phase diagrams were made from determined free volume based on density measurements and the temperature-pressure relation was estimated using the expansion coefficient of free volume and the temperature-pressure relation of the viscoelastic transition point. Next, the authors proposed the density-pressure-temperature relation and the viscosity-pressure-temperature relation of the tested oils based on the free volume and the phase diagrams. Moreover, it was shown that the Ehrenfest equation or the gradient of the phase diagram is closely related to the expansion coefficient of free volume.