Solution of dynamic characteristics of journal bearing based on two phase flow theory

The computational fluid dynamics(CFD) two phase flow and dynamic mesh technologies were applied to the numerical calculation of dynamic characteristics of journal bearing. A new journal bearing dynamic characteristic solving model using the two phase flow theory of CFD model was established. The two phase flow theory of computational fluid dynamics for the journal bearing dynamic characteristics did not need to define the oil film rupture boundary condition, and it can generate more complementary and more accurate flow information. The pressure distribution characteristics of the sliding bearing were compared, and the cavitation characteristics and the effects of the journal bearing were calculated. Finally, the effect of the two phase flow theory of CFD model on dynamic characteristics of journal bearing was analyzed. Calculation results show that the cavitation ratio increases significantly with the increase of rotating speed, eccentricity, and vaporization pressure, and decreases slowly with the increase of inlet pressure. Using two phase flow, calculation results also show that the direct stiffness increases, the cross stiffness decreases and the direct and cross dampings decrease. The deviation between the single phase flow and the two phase flow increases with the increase of eccentricity.