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A study is made of phase change in liquid face seals lubricate under laminar regime.A refined model of the energy equation for the mixture of two-phase flow is set up to replace the conven- tional energy equation.Instead of the early model that liquid ( water) is of a sudden transformed to vapor completely beyond the saturate point,the energy equation enables us to predict the thermal properties varying with mixture quality during flowing process.The influence of fluid density and dynamic viscosity due to the change of mixture quality on film temperature and hydro- dynamic pressure is investigated by differing the entrance and boundary conditions.The present results in comparison to the one based on the discrete show significant distinctions in thermal properties at the outlet. The factors of affecting the lubrication behavior of two-phase seal include the inlet temperature and pressure,the outlet pre- ssure,rotational speed and film thickness.This article will con- centrate on the solutions of mass flow rate,film thickness, fri- ctional force ,and mixture quality.Moreover,we make comparison between one-phase and two-phase seal happening situations. The result appears that changing the inlet pressure or temperature and under the conditions of fixed or flexible outlet pressure, temperature distribution will rise by the increase of rotational speed. The outlet pressure of flexible outlet pressure rises. And the position of phase change moves toward the direction of inlet. This article uses the two-phase flow to deal with the mixed condition of phase chang,but Lau's discrete model assume that liquid totally changes to vapor.Thus the pressure drop of this part is much greater than the two-phase model.
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