This paper presents the application of an improved Yasutomi correlation for lubricant viscosity at high pressure in a Newtonian\r\nelastohydrodynamic line contact simulation. According to recent experimental studies using high pressure viscometers, the Yasutomi\r\npressure-viscosity relationship derived fromthe free-volume model closely represents the real lubricant piezoviscous behavior\r\nfor the high pressure typically encountered in elastohydrodynamic applications. However, the original Yasutomi correlation suffers\r\nfrom the appearance of a zero in the function describing the pressure dependence of the relative free volume thermal expansivity.\r\nIn order to overcome this drawback, a new formulation of the Yasutomi relation was recently developed by Bair et al. This new\r\nfunction removes these concerns and provides improved precision without the need for an equation of state.Numerical simulations\r\nhave been performed using the improved Yasutomimodel to predict the lubricant pressure-viscosity, the pressure distribution, and\r\nthe film thickness behavior in a Newtonian EHL simulation of a squalane-lubricated line contact. This work also shows that this\r\nmodel yields a higher viscosity at the low-pressure area, which results in a larger central film thickness compared with the previous\r\npiezoviscous relations.
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