内外油膜间隙比对涡轮增压器转子系统失稳影响研究

Study on Effects of Clearance Ratio of Inner to Outer Oil Film on Turbocharger Rotor Instability

为获得浮环内、外油膜间隙比对涡轮增压器转子系统失稳规律的影响,建立了该转子系统动力学模型,并运用数值计算方法对其分析研究。结果表明,在较小间隙比时,内油膜涡动主导转子系统失稳区间;适当间隙比时,内油膜涡动主导转子低速转动时的失稳区间,外油膜涡动主导转子高速转动时的失稳的区间,在这两个失稳区间之间还存在运动稳定且微幅振动的"间歇区间";在较大间隙比时,外油膜涡动主导转子系统失稳区间。

To study the effects of clearance ratio of the inner to outer oil film in floating-ring bearing on turbocharger rotor instability, a dynamics model of the rotor system was established and then solved by numerical methods.The results show that when clearance ratio is small the inner oil whirl dominates the instability regions of the rotor system. When clearance ratio is neither too small nor too large, the inner oil whirl dominates the low speed instability region, while the outer oil whirl dominates the high speed instability region, and between these two regions, there is an interval region where the motion is stable with small vibration amplitudes. For large clearance ratio, the outer oil whirl dominates the instability regions.