油阻尼器油膜压强与厚度关系的实验研究

Experimental Research on Relation Between Oil-film Pressure and Thickness in Oil Damper

阻尼器是机械结构中起到减振作用的重要部件。在各种阻尼器中,油阻尼器的应用非常广泛,这种阻尼器工作时,可能同时存在着粘性和挤压油膜两种阻尼作用。本文以离心机结构中的一种油阻尼器为研究对象,围绕油膜压强和油膜厚度之间的关系展开研究工作。实验采用激振器对阻尼芯进行单向简谐激振,并调节油膜厚度、激振频率、激振功率等参数,进行多组实验,得到油膜压强随油膜厚度的变化曲线,显示出粘性阻尼器随着油膜厚度的减小,逐渐向挤压油膜阻尼器过渡的过程。同时根据挤压油膜理论,采用雷诺方程和有限长轴承近似方法推导出实验用阻尼器模型的油膜压强表达式,将实验结果与理论公式加以对比,并进行一定的分析和讨论。

The damper is an important part decreasing vibrations of mechanical structures. Oil damper is widely used in many fields among all sorts of dampers. Focusing on the relation between oil-film pressure and oil-film thickness, a type of oil damper of centrifuge is taken as a model. To simulate the process of the damper core under the actual working state, an exciter is used to drive the damper core to do harmonic vibration. A series of experiments are conducted by adjusting the working parameters such as oil-film thickness, exciting frequencies and exciting power levels and the relation curves are plotted. The results show that the viscous oil damper is gradually changed into the squeeze-film damper when the oil-film decreases. Based on the theory of squeeze-film, Reynolds equation and the theory of limited long-bearing are used to work out the oil-film pressure expression of SFD. Theoretical calculation is basically in accordance with the experimental data. Some differences between the theoretical and experimental results are discussed.